HomeMy WebLinkAboutCT 14-03; BEACHWALK AT MADISON; STORM WATER QUALITY MANAGEMENT PLAN (SWQMP); 2016-10-26CITY OF CARLSBAD
PRIORITY DEVELOPMENT PROJECT (PDP)
STORM WATER QUALITY MANAGEMENT PLAN (SWQMP)
FOR
800 GRAND AVENUE
CT XX-XX VRXX-XX
DWGXXX-XX
SWQMP NO. XX-XX
ENGINEER OF WORK:
B EXP 12-31-2016 DATE
PREPARED FOR:
EDMOND T. SHEHAB
800 GRAND MMKLC, LLC
800 GRAND AVENUE, SUITE
C16 CARLSBAD, CA 92008
858-342-9725
PREPARED BY:
bHA, I
5115 AVENIDA ENCINAS, SUITE L
CARLSBAD, CA 92008-4387
(760) 931-8700
DATE:
OCTOBER 26, 2016
w.o. 1026-1383-400
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TABLE OF CONTENTS
Certification Page
Project Vicinity Map
FORM E-34 Storm Water Standard Questionnaire
Site Information
FORM E-36 Standard Project Requirement Checklist
Summary of PDP Structural BMPs
Attachment 1: Backup for PDP Pollutant Control BMPs
Attachment 1 a: OMA Exhibit
Attachment 1 b: Tabular Summary of DMAs and Design Capture Volume Calculations
Attachment 1 c: Harvest and Use Feasibility Screening {when applicable)
Attachment 1d: Categorization of Infiltration Feasibility Condition (when applicable)
Attachment 1 e: Pollutant Control BMP Design Worksheets I Calculations
Attachment 2: Structural BMP Maintenance Thresholds and Actions
Attachment 3: Single Sheet BMP (SSBMP) Exhibit
Attachment 4: Geotechnical Reference
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Project Name: 800 Grand Avenue
Project ID: CDP XX-XX
CERTIFICATION PAGE
I hereby declare that I am the Engineer in Responsible Charge of design of storm water BMPs for
this project, and that I have exercised responsible charge over the design of the project as defined
in Section 6703 of the Business and Professions Code, and that the design is consistent with the
requirements of the BMP Design Manual, which is based on the requirements of SDRWQCB
Order No. R9-2013-0001 (MS4 Permit) or the current Order.
I have read and understand that the City Engineer has adopted minimum requirements for
managing urban runoff, including storm water, from land development activities, as described in
the BMP Design Manual. I certify that this SWQMP has been completed to the best of my ability
and accurately reflects the project being proposed and the applicable source control and site
design BMPs proposed to minimize the potentially negative impacts of this project's land
development activities on water quality. I understand and acknowledge that the plan check review
of this SWQMP by the City Engineer is confined to a review and does not relieve me, as the
Engineer in Responsible Charge of design of storm water BMPs for this project, of my
responsibilities for project design.
R.C.E. 60676 Exp. 12/31/2016
Engineer of Work's Signature, PE Number & Expiration Date
Bruce Rice
Print Name
bHA, I
October 26, 2016
Date
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PROJECT VICINITY MAP ..
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VI CINI TY MAP
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( City of
Carlsbad
STORM WATER STANDARDS
QUESTIONNAIRE
Development Services
Land Development Engineering
1635 Faraday Avenue
(760) 602-2750
www.carlsbadca.gov
E-34
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To address post-development pollutants that may be generated from development projects, the city requires that new
development and significant redevelopment priority projects incorporate Permanent Storm Water Best Management
Practices (BMPs) into the project design per Carlsbad BMP Design Manual (BMP Manual). To view the BMP Manual,
refer to the Engineering Standards (Volume 5).
This questionnaire must be completed by the applicant in advance of submitting for a development application
(subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of
storm water standards that must be applied to a proposed development or redevelopment project. Depending on the
outcome, your project will either be subject to 'STANDARD PROJECT' requirements or be subject to 'PRIORITY
DEVELOPMENT PROJECT' (PDP) requirements.
Your responses to the questionnaire represent an initial assessment of the proposed project conditions and impacts. City
staff has responsibility for making the final assessment after submission of the development application. If staff
determines that the questionnaire was incorrectly filled out and is subject to more stringent storm water standards than
initially assessed by you, this will result in the return of the development application as incomplete. In this case, please
make the changes to the questionnaire and resubmit to the city.
If you are unsure about the meaning of a question or need help in determining how to respond to one or more of the
questions, please seek assistance from Land Development Engineering staff.
A completed and signed questionnaire must be submitted with each development project application. Only one
completed and signed questionnaire is required when multiple development applications for the same project are
submitted concurrently.
PROJECT .INFORMATION
PROJECT NAME: 800 Grand Avenue PROJECT ID:
ADDRESS: 800 Grand Avenue, Carlsbad, CA 92008 APN: 203-202-18
The project is ( check one): ~ New Development D Redevelopment
The total proposed disturbed area is: ft2 ( ) acres
The total proposed newly created and/or replaced impervious area is: 36,612 ft2 ( 0.84 ) acres
If your project is covered by an approved SWQMP as part of a larger development project, provide the project ID and the
SWQMP # of the larger development project:
Project ID SWQMP#:
Then, go to Step 1 and follow the instructions. When completed, sign the form at the end and submit this with your
application to the city .
E-34 Page 1 of 4 REV 02/16
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. . ST.EP1
TO BE C()MPLETEI) FOR ALL PROJECTS ·' •
To determine if your project is a "development project", please answer the following question:
YES NO
Is your project LIMITED TO routine maintenance activity and/or repair/improvements to an existing building D ~ or structure that do not alter the size (See Section 1.3 of the BMP Design Manual for guidance)?
If you answered "yes" to the above question, provide justification below then go to Step 5, mark the third box stating "my
project is not a 'development project' and not subject to the requirements of the BMP manual" and complete applicant
information .
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Justification/discussion: (e.g. the project includes only interior remodels within an existing building):
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If vou answered "no" to the above question, the project is a 'development project', go to Step 2.
STEP2
TO BE COMPLETED FOR ALL DEVELOPMENT PR6JECTS
..... To determine if your project is exempt from PDP requirements pursuant to MS4 Permit Provision E.3.b.(3), please answer
the following questions:
Is your project LIMITED to one or more of the following:
YES NO
1. Constructing new or retrofitting paved sidewalks, bicycle lanes or trails that meet the following criteria:
a) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non-
erodible permeable areas; D D b) Designed and constructed to be hydraulically disconnected from paved streets or roads;
c) Designed and constructed with permeable pavements or surfaces in accordance with USEPA
·• Green Streets quidance?
2. Retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in D D accordance with the USEPA Green Streets guidance?
3. Ground Mounted Solar Array that meets the criteria provided in section 1.4.2 of the BMP manual? D D
If you answered "yes" to one or more of the above questions, provide discussion/justification below, then go to Step 5, mark
the second box stating "my project is EXEMPT from PDP ... " and complete applicant information.
Discussion to justify exemption ( e.g. the project redeveloping existing road designed and constructed in accordance with
the USEPA Green Street guidance):
If you answered "no" to the above questions, your project is not exempt from PDP, go to Step 3.
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To determine if your project is a PDP, please answer the following questions (MS4 Permit Provision E.3.b.( 1) ):
1. Is your project a new development that creates 10,000 square feet or more of impervious surfaces
collectively over the entire project site? This includes commercial, industrial, residential, mixed-use,
and ublic develo ment pro ·ects on public or private land.
2. Is your project a redevelopment project creating and/or replacing 5,000 square feet or more of
impervious surface collectively over the entire project site on an existing site of 10,000 square feet or
more of impervious surface? This includes commercial, industrial, residential, mixed-use, and public
develo ment ro ·ects on ublic or rivate land.
3. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more
of impervious surface collectively over the entire project site and supports a restaurant? A restaurant is
a facility that sells prepared foods and drinks for consumption, including stationary lunch counters and
refreshment stands selling prepared foods and drinks for immediate consumption (Standard Industrial
Classification SIC code 5812 .
4. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious
surface collectively over the entire project site and supports a hillside development project? A hillside
develo ment ro·ect includes develo ment on an natural slo e that is twent -five ercent or reater.
5. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more
of impervious surface collectively over the entire project site and supports a parking lot? A parking lot is
a land area or facility for the temporary parking or storage of motor vehicles used personally for
business or for commerce.
6. Is your project a new or redevelopment project that creates and/or replaces 5,000 square feet or more
of impervious surface collectively over the entire project site and supports a street, road, highway
freeway or driveway? A street, road, highway, freeway or driveway is any paved impervious surface
used for the transportation of automobiles, trucks, motorc c/es, and other vehicles.
7. Is your project a new or redevelopment project that creates and/or replaces 2,500 square feet or more
of impervious surface collectively over the entire site, and discharges directly to an Environmentally
Sensitive Area (ESA)? "Discharging Directly to" includes flow that is conveyed overland a distance of
200 feet or less from the project to the ESA, or conveyed in a pipe or open channel any distance as an
isolated flow from the project to the ESA i.e. not commin led with flows from ad·acent lands).*
8. Is your project a new development or redevelopment project that creates and/or replaces 5,000 square
feet or more of impervious surface that supports an automotive repair shop? An automotive repair
shop is a facility that is categorized in any one of the following Standard Industrial Classification {SIC}
codes: 5013, 5014, 5541, 7532-7534, or 7536-7539.
9. Is your project a new development or redevelopment project that creates and/or replaces 5,000 square
feet or more of impervious area that supports a retail gasoline outlet (RGO)? This category includes
RGO's that meet the following criteria: (a) 5,000 square feet or more or (b} a project Average Daily
Traffic ADT of 100 or more vehicles per da .
10. Is your project a new or redevelopment project that results in the disturbance of one or more acres of land
and are expected to generate pollutants post construction?
11. Is your project located within 200 feet of the Pacific Ocean and (1) creates 2,500 square feet or more of
impervious surface or (2) increases impervious surface on the property by more than 10%? (CMC
21.203.040
YES NO
D
D
D
D
D
D
D
D
D
D
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If you answered "yes" to one or more of the above questions, your project is a PDP. If your project is a redevelopment
project, go to step 4. If your project is a new project, go to step 5, check the first box stating "My project is a PDP ... "
and complete applicant information.
If you answered "no" to all of the above questions, your project is a 'STANDARD PROJECT.' Go to step 5, check the
second box statin "M ro·ect is a 'STANDARD PROJECT' ... " and com lete a licant information .
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Complete the questions below regarding your redevelopment project (MS4 Permit Provision E.3.b.(2)):
Does the redevelopment project result in the creation or replacement of impervious surface in an amount
of less than 50% of the surface area of the previously existing development? Complete the percent
impervious calculation below:
Existing impervious area (A}=-----------sq. ft.
Total proposed newly created or replaced impervious area (B) = ___________ sq. ft.
Percent impervious area created or replaced (B/A)*100 = ____ %
YES NO
D D
If you answered •yes", the structural BMPs required for PDP apply only to the creation or replacement of impervious
surface and not the entire development. Go to step 5, check the first box stating "My project is a PDP ... • and complete
applicant information.
If you answered "no.· the structural BM P's required for PDP apply to the entire development. Go to step s. check the
check the first box statin "M ro·ect is a PDP ... • and com lete a licant information . .,..,.... __
Ill My project is a POP and must comply with POP stormwater requirements of the BMP Manual. I understand l must
prepare a Storm Water Quality Management Plan (SWQMP) for submittal at time of application.
0 My project is a 'STANDARD PROJECT' OR EXEMPT from PDP and must only comply with 'STANDARD PROJECT'
stormwater requirements of the BMP Manual. As part of these requirements, I will submit a "Standard Project
Requirement Checklist Form E-36" and incorporate low impact development strategies throughout my project.
Note: For projects that are close to meeting the PDP threshold, staff may require detailed impervious area calculations
and exhibits to verify if 'STANDARD PROJECT stormwater requirements apply.
D My Project is NOT a 'development project' and is not subject to the requirements of the BMP Manual.
Applicant Information and Signature Box
Applicant Title: _.-C..,.t. .. "'-u+l----------
Date: /9 ~~ l 'Z
• Environmentally Sensitive Areas include t are not limited to all Clean ater Act Section 303{d) impaired water bodies; areas designated as Areas of Special
Biological Significance by the State Water Resources Control Board {Water Quality Control Plan for the San Diego Basin (1994) and amendments); water bodies
designated with ihe RARE beneficial use by the State Water Resources Control Board {Water Quality Control Plan for the San Diego Basin {1994) and
amendments); areas designated as preserves or their equivalent under the Multi Species Conservation Program Within the Cities and County of San Diego; Habitat
Management Plan; and any other equivalent environmentally sensitive areas which have been identified by the City.
This Box for City Use Onlv
YES NO
City Concurrence: D D
By:
Date:
Project ID:
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SITE INFORMATION CHECKLIST
Project Name
Project ID
Project Address
Assessor's Parcel Number(s) (APN(s))
Project Watershed (Hydrologic Unit)
Project Hydrologic Unit Hydrologic Area
Parcel Area
(total area of Assessor's Parcel(s)
associated with the project)
Area to be disturbed by the project
(Project Area)
Project Proposed Impervious Area
(subset of Project Area)
Project Proposed Pervious Area
(subset of Project Area)
800 Grand Avenue
CDP XX-XX
800 Grand Avenue, Carlsbad, CA 92008
203-202-18
~ Carlsbad 904
Select One:
D Loma Alta 904.1
D Buena Vista Creek 904.2
~ Agua Hedionda 904.3
D Encinas 904.4
D San Marcos 904.5
D Escondido Creek 904.6
0.96 Acres ( 41,906 Square Feet)
0.96 Acres 41,906 Square Feet)
0.84 Acres 36,612 Square Feet)
0.12 Acres ( 5,294 Square Feet)
Note: Proposed Impervious Area+ Proposed Pervious Area= Area to be Disturbed by the
Project.
This may be less than the Parcel Area.
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Current Status of the Site (select all that apply):
[8J Existing development
[8J Previously graded but not built out
D Agricultural or other non-impervious use
D Vacant, undeveloped/natural
Description I Additional Information:
The existing site is approximately 0.96 acres and has been previously graded. The site
currently includes three commercial buildings and a parking lot.
Existing Land Cover Includes (select all that apply):
D Vegetative Cover
[8J Non-Vegetated Pervious Areas
[8J Impervious Areas
Description I Additional Information:
The site is currently an impervious parking lot.
Underlying Soil belongs to Hydrologic Soil Group (select all that apply):
D NRCS Type A
[8J NRCS Type B
0 NRCS Type C
0 NRCS Type D
The on-site soil classification is Type-B from USGS Web Soil Survey.
Approximate Depth to Groundwater (GW):
D GW Depth < 5 feet
D 5 feet < GW Depth < 1 O feet
D 10 feet < GW Depth < 20 feet
[8J GW Depth > 20 feet
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Existing Natural Hydrologic Features (select all that apply):
D Watercourses
D Seeps
D Springs
D Wetlands
~ None
Description I Additional Information:
There are no existing natural hydrologic features .
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Description of Existing Site Topography and Drainage [How is storm water runoff conveyed
from the site? At a minimum, this description should answer (1) whether existing drainage
conveyance is natural or urban; (2) describe existing constructed storm water conveyance
systems, if applicable; and (3) is runoff from offsite conveyed through the site? if so, describe]:
Storm flows affecting the site are limited to the rainfall that lands directly on the property. Surface
runoff sheet flows south across the impervious parking lot to Grand Avenue. Runoff that drains
to Grand Avenue will be conveyed southwest via existing curb and gutter to the storm drain
system on Grand Avenue. Approximately 100% of the existing site is impervious .
The on-site soil classification is Type-B from USGS Web Soil Survey .
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Project Description I Proposed Land Use and/or Activities:
The project proposes the development of a multi-unit apartment complex with underground
parking. Proposed drainage improvements consist of two (2) biofiltration BMPs to provide
stormwater treatment and maintain the pre-developed runoff characteristics. The project drains
to one (1) Point of Compliance (POC) located to the southwest corner of the project site.
List/describe proposed impervious features of the project (e.g., buildings, roadways, parking
lots, courtyards, athletic courts, other impervious features):
The proposed impervious features of the project include the multi-unit apartment complex and
concrete sidewalks along the perimeter of the project site.
List/describe proposed pervious features of the project (e.g., landscape areas):
The proposed pervious features of the project include landscape areas surrounding the
apartment building and the proposed biofiltration basins in the front of the property.
Does the project include grading and changes to site topography?
cgj Yes
D No
Description I Additional Information:
Project grading will occur on approximately 0.96 acres of the project. Storm water flows from
impervious roof area will be conveyed via roof drains to the proposed biofiltration basins along
the southerly property boundary. The biofiltration basins will outlet via storm drains which will
discharge at proposed curb outlets on Grand Avenue. The storm drain system will require
excavation and installation of underground storm drains. Post-development site flow will mimic
existing drainage conditions, and will discharge from the site at below historical flow rates. See
the "Preliminary Drainage Study for 800 Grand Avenue" by BHA, Inc. dated October 26, 2016 for
post-development drainage calculations. Impervious surfaces have been minimized where
feasible .
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Does the project include changes to site drainage (e.g., installation of new storm water
conveyance systems)?
0Yes
0 No
Description I Additional Information:
Storm water runoff from the proposed project site is routed to a single POC located at the
southwest of the project site. The proposed drainage pattern will be similar to the existing
drainage pattern with some modifications to incorporate the Best Management Practices (BMPs)
into the project design to mimic the impacts on storm water runoff and quality. Runoff from the
developed project site is drained to two (2) onsite biofiltration BMPs (WQ-BMPs) for water quality
purposes (the project is not subject to hydromodification requirements). Once flows are routed
via the proposed WQ-BMPs, all flows are then conveyed via storm drain to the aforementioned
POC .
OMA 1 A and OMA 1 B encompasses runoff from the proposed building. Roof drains will collect
runoff and discharge into proposed biofiltration basins, BMP 1 A and BMP 1 B, located between
the southerly property line and the proposed building. The biofiltration basins will provide
stormwater treatment and flow detention. Treated water will discharge via storm drain pipes to
proposed curb outlets onto Grand Avenue.
Runoff from the concrete sidewalk area will intercepted by a private storm drain system and
conveyed to an underground vault located underneath the garage. The underground vault will be
sized as a cistern to store the volume from a 100 year storm event. Trench drains within the
underground garage will also collect miscellaneous storm water runoff and will convey flow to the
underground vault. A sump pump located in a pump room will pump storm water runoff to the
biofiltration basins for treatment based at a maximum of 0.03 cubic feet per second (13.5 gallons
per minute). For stormwater runoff greater than a 100-year storm event, a backup pump will start
automatically to empty the underground vault.
Small areas in the southern portion of the project will gravity flow towards Grand Avenue. The
landscape areas will be designed with native and/or drought tolerant species. These area are
considered Self-mitigating OMAs per Section 5.2.1 of the BMP DM and illustrated on the OMA
Exhibit.
The concrete sidewalk areas that gravity flow towards Grand Avenue are considered De Minimis
DMAs per Section 5.2.1 of the BMP OM. These impervious areas are less than 250 square feet
and are not considered to be a significant contributor of pollutants.
See Attachment 1 b for qualifying site design BMP calculations.
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Identify whether any of the following features, activities, and/or pollutant source areas will be
present (select all that apply):
[2J On-site storm drain inlets
[2J Interior floor drains and elevator shaft sump pumps
[2J Interior parking garages
[2J Need for future indoor & structural pest control
[2J Landscape/Outdoor Pesticide Use
D Pools, spas, ponds, decorative fountains, and other water features
D Food service
[2J Refuse areas
D Industrial processes
D Outdoor storage of equipment or materials
D Vehicle and Equipment Cleaning
D Vehicle/Equipment Repair and Maintenance
D Fuel Dispensing Areas
D Loading Docks
D Fire Sprinkler Test Water
D Miscellaneous Drain or Wash Water
[2J Plazas, sidewalks, and parking lots
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Describe path of storm water from the project site to the Pacific Ocean (or bay, lagoon, lake or
reservoir, as applicable):
From the project site, runoff flows to the Buena Vista Lagoon and to the Pacific Ocean.
List any 303(d) impaired water bodies within the path of storm water from the project site to the
Pacific Ocean (or bay, lagoon, lake or reservoir, as applicable), identify the
pollutant(s)/stressor(s) causing impairment, and identify any TMDLs for the impaired water
bodies:
303(d) Impaired Water Body Pollutant( s )/Stressor( s) TMDLs
Indicator bacteria Nia
Buena Vista Lagoon (904.21) Nutrients Nia
Sedimentation/siltation Nia
Identify pollutants expected from the project site based on all proposed use(s) of the site (see
BMP Design Manual Appendix B.6):
Not Applicable to the Expected from the Also a Receiving
Project Site Project Site Water Pollutant of
Pollutant Concern
Sediment D [8J [8J
Nutrients D [8J [8J
Heavy Metals D [8J D
Organic Compounds D [8J D
Trash & Debris D [8J [8J
Oxygen Demanding
Substances D [8J [8J
Oil & Grease D [8J D
Bacteria & Viruses D [8J [8J
Pesticides D [8J D
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Do hydromodification management requirements apply (see Section 1.6 of the BMP Design
Manual)?
0 Yes, hydromodification management flow control structural BMPs required.
0 No, the project will discharge runoff directly to existing underground storm drains
discharging directly to water storage reservoirs, lakes, enclosed embayments, or the
Pacific Ocean.
~ No, the project will discharge runoff directly to conveyance channels whose bed and bank
are concrete-lined all the way from the point of discharge to water storage reservoirs,
lakes, enclosed embayments, or the Pacific Ocean.
0 No, the project will discharge runoff directly to an area identified as appropriate for an
exemption by the WMAA for the watershed in which the project resides.
Description I Additional Information (to be provided if a 'No' answer has been selected above):
Storm water runoff from the project site flows southwest along Grand Avenue Street, enters a
storm drain on Grand Avenue, and ultimately discharges to the Buena Vista Lagoon. Based on
Section 1.6 of the City of Carlsbad BMP Design Manual, the City has the discretion to exempt a
PDP from hydromodification management requirements if discharge is conveyed via a concrete
lined system to an encased embayment (i.e. lagoon). Pursuant to the study approved by the
City of Carlsbad titled "Hydromodification Exemption Analyses for Select Carlsbad Watersheds"
dated September 17, 2015 prepared by Chang Consultants, the hydrologic and hydraulic
analyses performed showed that the hardened system downstream of the project draining to the
lagoon conveys the 10-year storm event, the discharge point has proper energy dissipation and
the outlet is within the 100-year flood limits.
Based on the maps provided within the WMAA, do potential critical coarse sediment yield
areas exist within the project drainage boundaries?
0Yes
~ No, No critical coarse sediment yield areas to be protected based on WMAA maps
If yes, have any of the optional analyses presented in Section 6.2 of the BMP Design Manual
been performed?
D 6.2.1 Verification of Geomorphic Landscape Units (GLUs) Onsite
O 6.2.2 Downstream Systems Sensitivity to Coarse Sediment
O 6.2.3 Optional Additional Analysis of Potential Critical Coarse Sediment Yield Areas Onsite
O No optional analyses performed, the project will avoid critical coarse sediment yield areas
identified based on WMAA maps
If optional analyses were performed, what is the final result?
0 No critical coarse sediment yield areas to be protected based on verification of GLUs
on site
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D Critical coarse sediment yield areas exist but additional analysis has determined that
protection is not required. Documentation attached in Attachment 8 of the SWQMP.
D Critical coarse sediment yield areas exist and require protection. The project will implement
management measures described in Sections 6.2.4 and 6.2.5 as applicable, and the areas
are identified on the SWQMP Exhibit.
Discussion I Additional Information:
Hydromodification requirements are not required for this project.
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List and describe point(s) of compliance (POCs) for flow control for hydromodification
management (see
Section 6.3.1 ). For each POC, provide a POC identification name or number correlating to the
project's HMP Exhibit and a receiving channel identification name or number correlating to the
project's HMP Exhibit.
Hydromodification requirements are not required for this project.
Has a geomorphic assessment been performed for the receiving channel(s)?
D No, the low flow threshold is 0.102 (default low flow threshold)
D Yes, the result is the low flow threshold is 0.102
D Yes, the result is the low flow threshold is 0.302
D Yes, the result is the low flow threshold is 0.502
If a geomorphic assessment has been performed, provide title, date, and preparer:
Discussion I Additional Information: (optional)
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When applicable, list other site requirements or constraints that will influence storm water
management design, such as zoning requirements including setbacks and open space, or
local codes governing minimum street width, sidewalk construction, allowable pavement
types, and drainage requirements.
On-site soil classification from NRCS Web Soil Survey is Type B. Infiltration testing performed
by Advanced Geotechnical Solutions, Inc. indicated that the soils located in the areas of the
proposed biofiltration basins have relatively high infiltration rates when thoroughly wet, similar
to typical Type B soils. However, the geotechnical engineer has stated that "infiltration is not
feasible due to the potential for water intrusion and potential for additional hydrostatic pressure
on subterranean garage. Accordingly infiltration on the 800 Grand portion of the site project is
not feasible." Therefore, the biofiltration basins will be lined with an impermeable liner to prevent
infiltration into native soils.
Currently, Grand Avenue lacks an underground storm drain system. This requires the proposed
WQ-BMPs and storm drain pipes to discharge flows onto Grand Avenue. Because the existing
and proposed slope of the site is relatively flat, the depths of the detention basins is very limited .
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( City of
Carlsbad
Project Name: 800 Grand Avenue
Project ID:
DWG No. or Building Permit No.:
STANDARD PROJECT
REQUIREMENT
CHECKLIST
E-36
Project Information
Source Control BMPs
Development Services
Land Development Engineering
1635 Faraday Avenue
(760) 602-2750
www.carlsbadca.gov
All development projects must implement source control BMPs SC-1 through SC-6 where applicable and feasible. See
Chapter 4 and Appendix E.1 of the BMP Design Manual for information to implement source control BMPs shown in this
checklist.
Answer each category below pursuant to the following.
• "Yes" means the project will implement the source control BMP as described in Chapter 4 and/or Appendix E.1 of the
Model BMP Design Manual. Discussion/justification is not required.
• "No" means the BMP is applicable to the project but it is not feasible to implement. Discussion/justification must be
provided. Please add attachments if more space is needed.
• "N/A" means the BMP is not applicable at the project site because the project does not include the feature that is
addressed by the BMP (e.g., the project has no outdoor materials storage areas). Discussion/justification may be
provided.
Source Control Requirement Applied?
SC-1 Prevention of Illicit Discharges into the MS4 0 Yes ONO D N/A
Discussion/justification if SC-1 not implemented:
Acknowledge that an illicit discharge is any discharge to the MS4 that is not composed entirely of wash water.
Provide educational materials to prevent illicit discharges as a component of the Operation and Maintenance Plan (O&M
Plan).
SC-2 Storm Drain Stenciling or Signage D Yes 0 No 0 NIA
Discussion/justification if SC-2 not implemented:
No onsite storm drain inlets proposed.
SC-3 Protect Outdoor Materials Storage Areas from Rainfall, Run-On, Runoff, and Wind D Yes D No 1i21 N/A Dispersal
Discussion/justification if SC-3 not implemented:
No outdoor materials storage areas proposed.
E-36 Page 1 of 4 Revised 03/16
Source Cc>ntroJ Reauirement (continued) Al>Dlied?
SC-4 Protect Materials Stored in Outdoor Work Areas from Rainfall, Run-On, Runoff, and OYes ONo 0 N/A Wind Dispersal
Discussion/justification if SC-4 not implemented:
No materials stored outdoors proposed.
SC-5 Protect Trash Storage Areas from Rainfall, Run-On, Runoff, and Wind Dispersal 0 Yes ONO 0 N/A
Discussion/justification if SC-5 not implemented:
Trash areas will be concrete lined and covered to protect from rainfall.
SC-6 Additional BMPs based on Potential Sources of Runoff Pollutants must answer for each source listed below and
identify additional BMPs. (See Table in Appendix E.1 of BMP Manual for Quidance). ... O On-site storm drain inlets OYes ONo 0 N/A
0 Interior floor drains and elevator shaft sump pumps i2I Yes ONo 0 N/A
0 Interior parking garages 0 Yes ONo 0 N/A
i2J Need for future indoor & structural pest control 0Yes ONO D NIA
i2J Landscape/Outdoor Pesticide Use 0Yes ONo D NIA
D Pools, spas, ponds, decorative fountains, and other water features OYes ONo i21 N/A
O Food service O Yes D No 0 N/A ..
i2J Refuse areas OYes D No D N/A
O Industrial processes OYes ONo 0 N/A
D Outdoor storage of equipment or materials OYes ONo 0N/A
D Vehicle and Equipment Cleaning OYes ONo 0 N/A
O Vehicle/Equipment Repair and Maintenance OYes ONo 0 N/A
O Fuel Dispensing Areas O Yes ONO 0 N/A
O Loading Docks O Yes D No 0 N/A
D Fire Sprinkler Test Water D Yes O No 1i21 N/A
O Miscellaneous Drain or Wash Water O Yes 0 No 0 N/A
i2J Plazas, sidewalks, and parkinQ lots 0Yes D No 0 NIA
For "Yes" answers, identify the additional BMP per Appendix E.1. Provide justification for "No" answers.
• Inspect and maintain interior parking garages and interior floor drains to prevent blockages and overflow.
• Plant pest-resistant or well-adapted plant varieties such as drought tolerant and/or native plants in landscape areas.
• Irrigation systems will be designed for the specific water requirements of each landscape area. Landscaping will be
designed to minimize irrigation and runoff, to promote surface infiltration where appropriate, and to minimize the use of
fertilizers and pesticides that can contribute to storm water pollution.
• Refuse areas will be concrete lined and covered to protect from rainfall.
• Plazas, sidewalks, and parking lots must be swept regularly to prevent the accumulation of litter and debris. Debris from
pressure washing must be collected to prevent entry into the storm drain system.
,,.
E-36 Page 2 of 4 Revised 03/16 ..
Sit. Pesl .. n BMPs
All development projects must implement site design BMPs SD-1 through SD-8 where applicable and feasible. See
Chapter 4 and Appendix E.2 thru E.6 of the BMP Design Manual for information to implement site design BMPs shown in
this checklist.
Answer each category below pursuant to the following.
• "Yes" means the project will implement the site design BMPs as described in Chapter 4 and/or Appendix E.2 thru E.6 of
the Model BMP Design Manual. Discussion I justification is not required.
• "No" means the BMPs is applicable to the project but it is not feasible to implement. Discussion/justification must be
provided. Please add attachments if more space is needed.
• "N/A" means the BMPs is not applicable at the project site because the project does not include the feature that is
addressed by the BMPs (e.g., the project site has no existing natural areas to conserve). Discussion/justification may be
provided.
.Source Contro.1 ~equ~r~i,n•nt I Applied?
SD-1 Maintain Natural Drainage Pathways and Hydrologic Features I 0Yes I D No ID N/A
Discussion/justification if SD-1 not implemented:
The project will maintain the overall cross lot drainage.
SD-2 Conserve Natural Areas, Soils, and Vegetation ID Yes I D No I 0 N/A
Discussion/justification if SD-2 not implemented:
The site is 80% impervious pre-development and 50% impervious post-development. Although the project cannot
conserve natural areas, the project will create vegetated areas.
SD-3 Minimize Impervious Area I i2I Yes I D No ID N/A
Discussion/justification if SD-3 not implemented:
Project will incorporate multi-story architecture to minimize impervious area.
SD-4 Minimize Soil Compaction I D Yes I D No I i2I N/A
Discussion/justification if SD-4 not implemented:
Project site has been previously graded.
SD-5 Impervious Area Dispersion I i2I Yes I D No ID N/A
Discussion/justification if SD-5 not implemented:
Runoff from impervious walkway areas will be directed to landscape areas prior to discharging to the MS4.
, ..
..
E-36 Page 3 of 4 Revised 03/16
Source Control Reautrement (contlpUEtd) I APPiied?
SD-6 Runoff Collection I OYes I ONo I i2I N/A
Discussion/justification if SD-6 not implemented:
Landscape areas are too small to effectively receive, treat, and infiltration runoff.
SD-7 LandscapinQ with Native or Drought Tolerant Species I i2I Yes I D No ID NIA
Discussion/justification if SD-7 not implemented:
Landscape or pervious areas will incorporate native or drought tolerant landscape design. Final selection of plant material
needs to be made by a landscape architect experienced with LID techniques.
'~
SD-8 Harvesting and Using Precipitation I OYes I D No I i21 NIA
Discussion/justification if SD-8 not implemented:
Harvest and use is considered to be infeasible for the project site. Project will utilize other LID strategies such as
minimizing impervious area to reduce the overall DCV of the site. See Form 1-7 in Attachment 1 c .
..
E-36 Page 4 of 4 Revised 03/16
'"
.. ..
SUMMARY OF PDP STRUCTURAL BMPS
All PDPs must implement structural BMPs for storm water pollutant control (see Chapter 5 of the
BMP Design Manual). Selection of PDP structural BMPs for storm water pollutant control must
be based on the selection process described in Chapter 5. PDPs subject to hydromodification
management requirements must also implement structural BMPs for flow control for
hydromodification management (see Chapter 6 of the BMP Design Manual). Both storm water
pollutant control and flow control for hydromodification management can be achieved within the
same structural BMP(s).
PDP structural BMPs must be verified by the local jurisdiction at the completion of construction.
This may include requiring the project owner or project owner's representative to certify
construction of the structural BMPs (see Section 1.12 of the BMP Design Manual). PDP
structural BMPs must be maintained into perpetuity, and the local jurisdiction must confirm the
maintenance (see Section 7 of the BMP Design Manual).
Use this form to provide narrative description of the general strategy for structural BMP
implementation at the project site in the box below. Then complete the PDP structural BMP
summary information sheet (page 3 of this form) for each structural BMP within the project (copy
the BMP summary information page as many times as needed to provide summary information
for each individual structural BMP).
Describe the general strategy for structural BMP implementation at the site. This information
must describe how the steps for selecting and designing storm water pollutant control BMPs
presented in Section 5.1 of the BMP Design Manual were followed, and the results (type of
BMPs selected). For projects requiring hydromodification flow control BMPs, indicate whether
pollutant control and flow control BMPs are integrated or separate.
For the purpose of this SWQMP, the proposed site condition has been divided into (8) Drainage
Management Areas (DMAs): (2) Areas Draining to Biofiltration IMPs, (4) Self-mitigating DMAs
and (2) De Minimis DMAs. The DMAs have been delineated based on onsite drainage patters
and BMP locations.
A geotechnical investigation was provided by Advanced Geotechnical Solutions, Inc. to perform
infiltration testing and analyze storm water infiltration feasibility. Based on recommendations
from the geotechnical report, infiltration rates for the 800 Grand site are greater than 0.5 in/hr.
However, the conclusions and recommendation section in Appendix D state that "infiltration is
not feasible due to the potential for water intrusion and potential for additional hydrostatic
pressure on subterranean garage. Accordingly infiltration on the 800 Grand portion of the site
project is not feasible."
Since infiltration is considered infeasible, biofiltration basins (BF-1) were chosen as the structural
BMP for DMAs draining to IMPs. The biofiltration basins have been sized based on the
minimum sizing factor of 3% for storm water pollutant control requirements. The DCV for each
19
""
OMA has been calculated based on the proposed impervious and pervious areas draining to
each BMP. Worksheet B.5-1 in Attachment 1e further demonstrates that the DCV can be fully
biofiltered within the storage layers, and the stored effective depth draws down no longer than 36
hours.
Two (20 WQ-BMP biofiltration basins (BF-1) will be used for pollutant control and peak flow control
for the project stormwater runoff. In developed conditions, the basins will have a surface depth of
1.2 feet. The basins will be configured with a 10-inch ponding layer above the surface for storage
volume, an 18-inch layer of amended soil below the surface, and a 10-inch gravel storage layer
below the amended soil layer to accommodate the French drain system. Below the gravel layer
the basins are lined to prevent infiltration into the underlying soil. Flows will discharge from the
basins via perforated underdrain pipe within the gravel layer to the receiving storm drain system.
A riser structure will be constructed within the BMPs with an emergency overflow set 10-inches
above the bottom of the basin, such that peak flows can be safely discharged to the receiving
storm drain system.
20
Structural BMP ID No. BMP 1A
DWG Sheet No. 2
Type of structural BMP:
D Retention by harvest and use (HU-1)
D Retention by infiltration basin (INF-1)
D Retention by bioretention (INF-2)
D Retention by permeable pavement (INF-3)
D Partial retention by biofiltration with partial retention (PR-1)
IX! Biofiltration (BF-1) D Flow-thru treatment control with prior lawful approval to meet earlier PDP requirements
(provide BMP type/description in discussion section below)
D Flow-thru treatment control included as pre-treatmenUforebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
D Flow-thru treatment control with alternative compliance (provide BMP type/description in
discussion section below)
D Detention pond or vault for hydromodification management
D Other (describe in discussion section below)
Purpose:
IX! Pollutant control only
D Hydromodification control only
D Combined pollutant control and
hydromodification control D Pre-treatmenUforebay for another structural
BMP D Other (describe in discussion section below)
Discussion (as needed):
Hydromodification requirements are not required for this project. The WQ-BMP is for pollutant
control only.
21
..
..
Structural BMP ID No. BMP 1 B
DWG Sheet No. 2
Type of structural BMP:
0 Retention by harvest and use (HU-1)
0 Retention by infiltration basin (INF-1)
0 Retention by bioretention (INF-2)
0 Retention by permeable pavement (INF-3)
0 Partial retention by biofiltration with partial retention (PR-1)
rgj Biofiltration (BF-1)
0 Flow-thru treatment control with prior lawful approval to meet earlier PDP requirements
(provide BMP type/description in discussion section below)
0 Flow-thru treatment control included as pre-treatment/forebay for an onsite retention or
biofiltration BMP (provide BMP type/description and indicate which onsite retention or
biofiltration BMP it serves in discussion section below)
0 Flow-thru treatment control with alternative compliance (provide BMP type/description in
discussion section below)
0 Detention pond or vault for hydromodification management
0 Other (describe in discussion section below)
Purpose:
rgj Pollutant control only
0 Hydromodification control only
0 Combined pollutant control and
hydromodification control
0 Pre-treatment/forebay for another structural
BMP
0 Other ( describe in discussion section below)
Discussion (as needed):
Hydromodification requirements are not required for this project. The WQ-BMP is for pollutant
control only.
22
""
ATTACHMENT 1
BACKUP FOR PDP POLLUTANT CONTROL BMPS
This is the cover sheet for Attachment 1.
Check which Items are Included behind this cover sheet:
Attachment Contents Checklist
Sequence
Attachment 1 a OMA Exhibit (Required) r8] Included
Attachment 1 b
See OMA Exhibit Checklist on the
back of this Attachment cover sheet.
(24"x36" Exhibit typically required)
Tabular Summary of DMAs Showing
OMA ID matching OMA Exhibit, OMA
Area, and OMA Type (Required)*
*Provide table in this Attachment OR
on OMA Exhibit in Attachment 1 a
0 Included on OMA Exhibit in
Attachment 1 a
r8J Included as Attachment 1 b,
separate from OMA Exhibit
Attachment 1c Form 1-7, Harvest and Use Feasibility r8J Included
Attachment 1 d
Screening Checklist (Required unless O Not included because the entire
the entire project will use infiltration project will use infiltration BMPs
BMPs)
Refer to Appendix B.3-1 of the BMP
Design Manual to complete Form I-7.
Form 1-8, Categorization of Infiltration
Feasibility Condition (Required
unless the project will use harvest and
use BMPs)
Refer to Appendices C and D of the
BMP Design Manual to complete
Form 1-8.
r8] Included
0 Not included because the entire
project will use harvest and use
BMPs
Attachment 1 e Pollutant Control BMP Design r8] Included
Worksheets I Calculations (Required)
Refer to Appendices B and E of the
BMP Design Manual for structural
pollutant control BMP design
guidelines
23
...
Attachment 1 a
OMA Exhibit
24
!SD-1
!SD-3
!SD-5
!SD-7
I ____ ,
LID AND SITE DESIGN:
MAINTAIN NATURAL DRAINAGE PATHWAYS AND HYDROLOGIC FEATURES.
MINIMIZE IMPERVIOUS AREA
IMPERVIOUS AREA DISPERSION
LANDSCAPING WITH NAT/VE OR DROUGHT TOLERANT SPECIES
K:\Civil 3D\1383\GRAND\DWG\SWMP\1383-800 Grand-DMA Exhibit 10-26-16.dwg, 10/26/2016 4:27:49 PM
--------~----------------.
DRAINAGE MANAGEMENT AREA EXHIBIT
800G VAVENUE
'
I ' ! i I ·-·-··-------·--·----,------~--------'
. J
\
\
/"7 ,/ / [ i , J '
I I"('""'\
0 r-. "'-1 '
SOURCE CONTROL BMPS:
I sc-11 PREVENTION OF ILLICIT DISCHARGES INTO THE MS4
!SC-2! STORM DRAIN STENCILING AND SIGNAGE
!SC-5! PROTECT TRASH STORAGE AREAS
!SC-6 ! ADDITIONAL BMPS BASED ON POTENTIAL RUNOFF POLLUTANTS:
[A] ON-SITE STORM DRAIN INLETS
[[] INTERIOR FLOOR DRAINS AND ELEVA TOR SHAFT SUMP PUMPS
CQ:I INTERIOR PARKING GARAGES
[ill NEED FOR FUTURE INDOOR & STRUCTURAL PEST CONTROL
[(] LANDSCAPE/OUTDOOR PESTICIDE USE
[8J TRASH OR REFUSE AREAS
[QJ FIRE SPRINKLER TEST WATER
[£] MISCELLANEOUS DRAIN OR WASH WATER
[ill PLAZAS, SIDEWALKS, DRIVEWAYS, AND PARKING LOTS
----------------------------
A.
I . '
Ii
i! :'
j i
i
' ' f-
l
---------.-------,-
SELF-MITIGATING DMAS:
VEGETA T/ON IN THE NATURAL OR LANDSCAPE AREA IS NATIVE OR NON-NATIVE DROUGHT
TOLERANT SPECIES.
/
0
. SOILS ARE UNDISTURBED NATIVE TOPSOIL, OR DISTURBED SOILS HA VE BEEN AMENDED AND
AERATED TO PROMOTE WATER RETENTION CHARACTER/ST/CS EQUIVALENT TO UNDISTURBED NAT/VE TOPSOIL.
INCIDENTAL IMPERVIOUS AREAS ARE LESS THAN 5 PERCENT OF THE SELF-MITIGATING AREA.
IMPERVIOUS AREAS CALCULATED WITHIN THE SELF-MITIGATED AREA SHOULD NOT BE
HYDRAULICALLY CONNECTED TO OTHER IMPERVIOUS AREAS UNLESS IT IS A STORM WATER
CONVEYANCE SYSTEM (SUCH AS BROW DITCHES).
THE SELF-MIT/GA TING AREA IS HYDRAULICALLY SEPARATE FROM DMAS THAT CONTAIN PERMANENT
STORM WATER POLLUTION CONTROL BMPS.
DE MINIMIS DMAS:
DE MIN/MIS DMAS ARE AREAS THAT ARE VERY SMALL AND THEREFORE NOT CONSIDERED TO BE
SIGNIFICANT CONTRIBUTORS OF POLLUTANTS, AND ARE CONSIDERED NOT PRACTICAL TO DRAIN TO A BMP. ·
DE MIN/MIS DMAS ARE AREAS ABUT THE PERIMETER OF THE DEVELOPMENT SIT£
THE PORTION OF THE SITE FALLING INTO THIS CATEGORY IS MINIMIZED THROUGH EFFECTIVE SITE DESIGN.
EACH DE MIN/MIS DMA SHOULD BE LESS THAN 250 SQUARE FEET AND THE SUM OF ALL DE
MIN/MIS DMAS SHOULD REPRESENT LESS THAN 2 PERCENT OF THE TOTAL ADDED OR REPLACED IMPERVIOUS SURFACE OF THE PROJECT.
TWO DE MIN/MIS DMAS CANNOT BE ADJACENT TO EACH OTHER AND HYDRAULICALLY CONNECTED.
------------------·--------------------~------
..-~ --c ' .
I
I
\
' \
20· 10·
bJ.iA,lnc.
LEGEND SYMBOL
-~~-~-:-;~-1----,(s-F"'";------------i( 3:i~~51 SF)
SELF-MIT/GA TING DMA SM 1
DE MIN/MIS DMA DMIN 1
POINT OF CONCENTRATION POC 1
DMA BOUNDARY
PROPERTY LINE
FLOW DIRECTION
PROPOSED CONCRETE SIDEWALK
PROPOSED 8/0FIL TRA TION BASIN
-r · · · ·· · · · ··· · ···· 1 ··················· ................... ................... ................... r . ·. · .1
PROJECT CHARACTERISTICS
PARCEL AREA 0.96 ACRES
DISTURBED AREA 0.96 ACRES
PROPOSED IMPERVIOUS AREA 0.84 ACRES
PROPOSED PERVIOUS AREA 0.12 ACRES
.
SOIL TYPE B
DEPTH TO GROUNDWATER > 20 FEET
BMP FOOTPRINT
DOWNSPOUT---
STRUCTURAL--r'
WALLS W/
WATERPROOF
MEMBRANE
SPLASH PAI}--_..-
..,.!---24"x24" BROOKS
CATCH BASIN W/
GRATED INLET
1.2' '· PLAN71NGS
MULCH LAYER
(3" MIN)
,.4,?.ir.j--18" MIN
ENGINEERED
SOIL MEDIA
c+--2" PEA GRAVEL
IMPERMEABLE
UNER :i;~~:i:'.9::!~~~t--10• AGGREGATE
·••· · .• •.· · •. · • . c' STORAGE LA YER
6" -DIA PERFORATED
PVC PIPE
SUBGRADE --3• AGGREGATE BELOW
UNDERDRAIN
BIOFILTRATION BASIN
DETAIL, TYPICAL
NOT TD SCALE
BMP FOOTPRINT
BASIN PROPOSED BASIN
AREA
BMP 1A 861 SF
BMP 18 861 SF
o· 20· 40' ~~---60'
SCALE: 1'' = 20'
DRAINAGE MANAGEMENT
AREA EXHIBIT
800 GRAND A VENUE
land planning, cMI englneeiing, :ruweylng CARLSBAD, CA 5115 AVENIDA ENCINAS
SUITE "L"
CARLSBAD, CA. 92008-4387
(760) 931-8700 W0.1026-1383-400 SHEET 1 OF 1
Attachment 1 b
Tabular Summary of DMAs and Design Capture Volume Calculations
DMA Surface Tabulation to Support Biofiltration of Design DMAName
Capture Volume (DCV) Determination -DMA1A
DMA Impervious Area Tabulation
"
Surface Name Surface Type Area (ftl
Rl Roof 16,335
PCCl Driveway 348
PCC3 Concrete Sidewalk 1,720
Total Impervious Area {ftl 18,403 ..
DMA Pervious Area Tabulation
.. Surface Name Surface Type Area (ftl
L1 Landscape 1,861
Total Pervious Area {ftl 1,861
Total DMA (A) 20,264
Total Impervious Area (ftl /Total DMA (ftl = Percent Impervious 91%
Soil Type B
DMA Runoff Coefficient "C" 0.84
85th Percentile Rainfall (I) 0.6
Design Capture Volume (DVC) = (C)(I){A) /12 856
..
..
25
"'
DMA Surface Tabulation to Support Biofiltration of Design DMAName
Capture Volume (DCV) Determination -DMA1B
DMA Impervious Area Tabulation
Surface Name Surface Type Area (ft1
R2 Roof 16,335
PCC2 Driveway 348
PCC4 Concrete Sidewalk 1,720
Total Impervious Area (ft1 18,403
DMA Pervious Area Tabulation ..
Surface Name Surface Type Area (ft1
L2 Landscape 1,861
Total Pervious Area (ft1 1,861
Total DMA (A) 20,264
Total Impervious Area (ft1 /Total DMA (ft1 = Percent Impervious 91%
Soil Type B
OMA Runoff Coefficient "C" 0.84
85th Percentile Rainfall (I) 0.6
Design Capture Volume (DVC) = (C)(l)(A) /12 856 ..
.•
..
26
Tabulation of Self-Mitigating DMAs-SM 1
Surface Name Surface Type Area (ft2)
L3 Landscape 507
Subtotal Pervious Area 507
Roof 0
PCC 0
Subtotal Impervious Area 0
'"
Total Self-Mitigating Area 507
" Percent Impervious Area (Not to Exceed 5(%) 0%
...
Tabulation of Self-Mitigating DMAs-SM 2
Surface Name Surface Type 2 Area (ft)
IA Landscape 507
Subtotal Pervious Area 507
Roof 0
PCC 0
Subtotal Impervious Area 0
Total Self-Mitigating Area 507
Percent Impervious Area (Not to Exceed 5(10) 0%
27
...
Tabulation of Self-Mitigating DMAs-SM 3
Surface Name Surface Type 2 Area (ft)
LS Landscape 62
Subtotal Pervious Area 62
Roof 0
PCC 0
Subtotal Impervious Area 0
Total Self-Mitigating Area 62
Percent Impervious Area (Not to Exceed 5'1o) 0%
Tabulation of Self-Mitigatil)g DMAs-SM 4
Surface Name Surface Type 2 Area (ft)
L6 Landscape 62
Subtotal Pervious Area 62
Roof 0
PCC 0
Subtotal Impervious Area 0
Total Self-Mitigating Area 62
Percent Impervious Area (Not to Exceed 5%) 0%
According to Chapter 5.2.1 of the City of Carlsbad BMP Design Manual, a DMA is considered "Self-
mitigating" if the DMA consists of natural or landscape areas that drain directly offsite. The self-
mitigating areas either are landscaped areas with native and/ or drought tolerant species that do not
require regular application of fertilizers and pesticides, or disturbed soils that have been amended and
aerated to promote water retention characteristics equivalent to undisturbed native topsoil.
The locations and limits of all Self-Mitigating DMAs are delineated on the DMA Exhibit.
28
,.
...
Tabulation of De Minimis DMAs-DMIN 1
Surface Name Surface Type Area (ft2)
L Landscape 0
Subtotal Pervious Area 0
Roof 0
PCC16 PCC 120
Subtotal Impervious Area 120
Total De Minimis Area 120
Percent Impervious Area (Not to Exceed 2'Yo) 0%
Tabulation of De Minimis DMAs-DMIN 2
Surface Name Surface Type 2 Area (ft)
L Landscape 0
Subtotal Pervious Area 0
Roof 0
PCC17 PCC 120
Subtotal Impervious Area 120
Total De Minimis Area 120
Percent Impervious Area (Not to Exceed 2%)1 0%
According to Chapter 5.2.2 of the City of Carlsbad BMP Design Manual, a DMA is considered "De
Minimis" if the DMA consists of areas that are very small and therefore not considered to be
significant contributor of pollutant, and are considered not practicable to drain to a BMP. The de
minimis DMAs are driveway aprons connecting to the existing streets and are about the perimeter of
the development site. Each DMA is also less than 250 square feet and the sum of all de minimis
DMAs is less than 2 percent of the total added or replaced impervious surface of the project.
Furthermore, the portion of the site falling to this category is minimized through effective site design.
The locations and limits of all De Minimis DMAs are delineated on the DMA Exhibit .
29
..... 1••11·~··--·~ ..
DMA Classification Quantitv Subtotal DMA (ft2~ Subtotal DMA (acres)
Self-Mitigating DMAs 4 1,138 0.03
Self-Retaini112: DMAs 0 0 0
Surfaces Draining to Self-Retaining DMAs 0 0 0
Bioretention !MPs 2 40,528 0.93
Flow Through Planter !MPs 0 0 0
Infiltration IMP 0 0 0
Conventional Vegetated Swale 0 0 0
Extended (Dry) Detention Basins 0 0 0
Media (Sand) Filter 0 0 0
\Vet Pond 0 0 0
Constructed Wetland 0 0 0
Proprietary Vault/Tree Well 0 0 0
Proprietary Inlet Filter 0 0 0
De Minimis DMAs 2 240 0.01
Total Project DMA 41,906 0.96
Total Parcel Area 41,906 0.96
Comment:
30
I
Attachment 1 c
Form 1-7, Harvest and Use Feasibility Screening Checklist
Harvest and Use Feasibility Checklist Form I-7
1. Is there a demand for harvested water (check all that apply) at the project site that is reliably present during the
wet season?
[8J Toilet and urinal flushing
[8J Landscape irrigation
D Other:
2. If there is a demand; estimate the anticipated average wet season demand over a period of 36 hours. Guidance
for planning level demand calculations for toilet/ urinal flushing and landscape irrigation is provided in Section
B.3.2.
Modified ETWU = ETo\\'etX [[I(PF x HA)/IE] + SIA] x 0.015
Using an average value for HA over the 14 lots and Low Plant Water Use (per Table B.3-2);
Modified ET\VU = 2.7 x [[(0.2 x 5,294)/0.9] + OJ x 0.015
Modified ETWU= 476
3. Calculate the DCV using worksheet B-2.1.
DCV = 1699 (cubic feet)
3a. Is the 36 hour demand greater
than or equal to the DCV?
D Yes I ~ No
.0. c::>
Harvest and use appears to be
feasible. Conduct more detailed
evaluation and sizing calculations to
confirm that DCV can be used at an
adequate rate to meet drawdown
criteria.
3b. Is the 36 hour demand greater than
0.25DCV but less than the full DCV?
~ Yes I D No
.0. c::>
Harvest and use may be feasible.
Conduct more detailed evaluation and
sizing calculations to determine
feasibility. Harvest and use may only
be able to be used for a portion of the
site, or (optionally) the storage may
need to be upsized to meet long term
capture targets while draining in longer
than 36 hours.
31
3c. Is the 36 hour demand
less than 0.25DCV?
D Yes
.0.
Harvest and use is considered
to be infeasible.
•
'"
Is harvest and use feasible based on further evaluation?
D Yes, refer to Appendix E to select and size harvest and use BMPs.
~ No, select alternate BMPs
Harvest and use BMPs are considered infeasible. The space available to construct a cistern is severely limited.
Project will implement other LID strategies such as minimizing impervious area and impervious area dispersion .
The full DCV can be treated and detained in the proposed biofiltration basins.
32
,qi
..
....
Attachment 1 d
Form 1-8, Categorization of Infiltration Feasibility Condition
Form 1-8
fart 1.,... fµll Inpltratjpn feasibility Scteerung Cdteria
Would infiltration of the full design volume be feasible from a physical perspective without any
undesirable consequences that cannot be reasonably mitigated?
Criteria
1
Screening Question
Is the estimated reliable infiltration rate below proposed
facility locations greater than 0.5 inches per hour? The
response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix
C.2 and Appendix D.
Provide basis:
Yes No
Yes
From the geotechnical report by Advanced Geotechnical Solutions, Inc., two borehole percolation tests
were performed in the proposed/possible BMP locations-portion P-1 and P-2. Testing was performed in
general conformance with Appendix D, Section D.3.3.2 of the recently adopted BMP Design Manual. The
stabilized percolation rates were then converted to infiltration rates using the "Porchet Method". The
observed infiltration rates were calculated to be greater than 0.5 inches per hour. Using a factor of safely
of 2 for feasibility screening purpose yielded design infiltration rates greater than 0.5 inches per hour for
the 800 Grand condominium site. See Attachment 5 for copy of geotechnical reports and results of
percolation testing are presented in Form 1-8.
2
Can infiltration greater than 0.5 inches per hour be allowed
without increasing risk of geotechnical hazards (slope
stability, groundwater mounding, utilities, or other factors)
that cannot be mitigated to an acceptable level? The response
to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2.
Provide basis:
Yes No
Based on recommendations from the geotechnical report, infiltration rates for the 800 Grand site are
greater than 0.5 in/hr. However, the conclusions and recommendation section state that "infiltration is
not feasible due to the potential for water intrusion and potential for additional hydrostatic pressure on
subterranean garage. Accordingly infiltration on the 800 Grand portion of the site project is not feasible."
33
Form 1-8 Page 3 of 4
Pan 2 -Pattial lnfiltmtion ys. No lnfiluation Feasibility ~ning Criteria
Would infUuation of water in any appreciabJe atnount be physically feasible without any negative
consequences that cannot be reasonably mitigated?
Criteria
5
Screening Question
Do soil and geologic conditions allow for infiltration in
any appreciable rate or volume? The response to this
Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2 and
Appendix D.
Provide basis:
Yes No
Yes
According to the geotechnical report, "Site specific infiltration testing yielded infiltration rates of greater
than 0.5 inches/hour. The sandy nature of the subsurface materials beneath the site, allow for infiltration
in any appreciable rate of volume. It is anticipated that over the lifetime of the development the infiltration
rates will further diminish. The BMP Design Manual utilizes the subjective terminology of 'appreciable'
and fails to define a lower bound infiltration rate. It is our current understanding that an 'appreciable'
infiltration rate is interpreted to be any perceptible amount of infiltration. Therefore, in consideration of
the current interpretation, the soil and geologic conditions at the project site allow for infiltration in an
appreciable rate or volume."
6
Can Infiltration in any appreciable quantity be allowed
without increasing risk of geotechnical hazards (slope
stability, groundwater mounding, utilities, or other
factors) that cannot be mitigated to an acceptable
level? The response to this Screening Question shall be
based on a comprehensive evaluation of the factors
presented in Appendix C.2.
Provide basis:
No
Based on recommendations from the geotechnical report, infiltration rates for the 800 Grand site are
greater than 0.5 in/hr. However, the conclusions and recommendation section state that "infiltration is
not feasible due to the potential for water intrusion and potential for additional hydrostatic pressure on
subterranean garage. Accordingly infiltration on the 800 Grand portion of the site project is not feasible."
35
Attachment 1 e
Pollutant Control BMP Design Worksheets I Calculations
37
Factor of Safety and Design Infiltration Rate
Worksheet Worksheet D.5-1
Factor Product
Factor Category Factor Description Assigned Value (p) Weight (w) (v) p=wxv
Soil assessment methods 0.25 2 0.5
Predominant soil texture 0.25 1 0.25
Suitability Site soil variability 0.25 1 0.25 A Assessment Depth to groundwater I
impervious layer 0.25 1 0.25
Suitability Assessment Safety Factor, SA = Ip 1.25
Level of pretreatment/ expected 0.5 1 0.5 sediment loads
B Design Redundancy/ resiliency 0.25 1 0.25
Compaction during construction 0.25 1 0.25
Design Safety Factor, SB = Ip 1.0
Combined Safety Factor, Sro,a1= SA x SB 1.25, use 2.0*
Observed Infiltration Rate, inch/hr, K,bsmed BMP 1A; BMP 1B
(corrected for test-specific bias) 2.83; 2.0
Design Infiltration Rate, in/hr, Kdcsign = K,bsmed I Sro,al
BMP1A;BMP1B
1.42; 1.0
Supporting Data
Briefly describe infiltration test and provide reference to test forms:
Percolation testing and infiltration rate results were provided by Advanced Geotechnical Solutions, Inc.
(see Attachment 4). The areas of the proposed biofiltration areas (two total) were tested utilizing City
of Carlsbad BMP Design Manual standards for percolation testing. Based up on the test results, the
infiltration rates were found to be:
P-1 (BMP 1B) -Infiltration Rate = 1.42 in/hr
P-2 (BMP 1A) -Infiltration Rate= 1.0 in/hr
*The infiltration rate results provided by the geotechnical engineer use a factor of safety of 2.0.
At the direction of the geotechnical engineer, the infiltration rate will use a factor of safety of
2.0 to adopt a more conservative basin design.
38
~un il • , Y·-~~ ,r,1' •nT,. ,1rnuu ,Tn•!ib~I :11,~,u.-.
emaining DCV after implementing retention BMPs 856 cubic-feet
Partial Retention
2 Infiltration rate from Worksheet D.5-1 if partial infltration is feasible 0 in/hr.
3 Allowable drawdown time for aggregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated [Line 2 x Line 3] 0 inches
5 IA2:1!:tegate pore space 0.4 in/in
6 Required depth of gravel below the underdrain [Line 4 / Line 51 0 inches
7 Assumed surface area of the biofiltration BMP 861 sq-ft
8 Media retained pore space 0.1 in/in
9 Volume retained by BMP frLine 4 + (Line 12 x Line 8)]/121 x Line 7 0 cubic-feet
10 DCV that requires biofiltration [Line 1 -Line 9] 856 cubic-feet
c" BM,P Parameters
11 Surface Ponding [6 inch minimum, 12 in maximum] 10 inches
12 Media Thickness [18 inches minimum] 18 inches
13 Aggregate Storage above underdrain invert (12 inches typical -use O inches
10 inches for sizing if ag6>regate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing 5 in/hr.
Bate'line CaleulatiQn
16 Allowable Routing Time for sizing 6 hours
17 Depth filtered during storm [Line 15 x Line 16] 30 inches
18 Depth of Detention Storage 17.6 inches
[Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)1
19 Total Depth Treated [Line 17 + Line 18] 47.6 inches
Option i · Biofilter 1.5 times the DCV
20 Required biofiltered volume fl .5 x Line 1 OJ 1,284 cubic-feet
21 Required Footprint [Line 20 / Linel 9] x 12 324 sq-ft
Ot>tion 2 • Store O. 75 of remainirur DCV in pores and pondin2
22 Required Storage (surface + pores) Volume f0.75 x Line 10] 642 cubic-feet ..
23 Required Footprint [Line 22 / Line 181 x 12 438 sq-ft
Footr>rint of the BMP
24 Area draining to the BMP 20,264 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.84
26 Minimum BMP Footprint [Line 24 x Line 25 x 0.03] 514 sq-ft
27 Footprint of the BMP = Maximum(Minimum(Line 21, Line 23), Line 26) 514 sq-ft
28 Used BMP Footprint 861 sq-ft
39
~ 111 • ,.. •·ru•rrfTi•.,,_,._" ,. :111~1
Remaining DCV after implementing retention BMPs
Ml•~•:.ll!l•~,:'1nii~"laT"""q• ,._,,...
856 cubic-feet
Partial Retention
2 Infiltration rate from Worksheet D.5-1 if partial infltration is feasible 0 in/hr,
3 Allowable drawdown time for a1mregate storage below the underdrain 36 hours
4 Depth of runoff that can be infiltrated [Line 2 x Line 31 0 inches
5 !Aggregate pore space 0.4 in/in
6 Required depth of gravel below the underdrain [Line 4 / Line 51 0 inches
7 Assumed surface area of the biofiltration BMP 861 sq-ft
8 Media retained pore space 0.1 in/in
9 Volume retained by BMP f[Line 4 + (Line 12 x Line 8)1/121 x Line 7 0 cubic-feet
10 DCV that requires biofiltration [Line 1 -Line 9] 856 cubic-feet
'· •,:· .. ·: ',, B:MJ> Patatnetets
11 Surface Ponding [6 inch minimum, 12 in maximuml 10 inches
12 Media Thickness [18 inches minimuml 18 inches
•
13 Aggregate Storage above underdrain invert (12 inches typical -use O inches 10 inches for sizing if aggregate is not over the entire bottom surface area
14 Media available pore space 0.2 in/in
15 Media filtration rate to be used for sizing 5 in/hr.
Baselint,:. Calculation
16 Allowable Routing Time for sizing 6 hours
17 Depth filtered during storm [Line 15 x Line 16] 30 inches
18 Depth of Detention Storage 17.6 inches [Line 11 + (Line 12 x Line 14) + (Line 13 x Line 5)1
19 Total Depth Treated [Line 17 + Line 181 47.6 inches
Option i. Biofilter 1.5 times the DCV
20 Required biofiltered volume fl .5 x Line 1 OJ 1,284 cubic-feet
21 Required Footprint [Line 20 / Line1 91 x 12 324 sq-ft
Option 2,. Store 0.75 ofremainina DCV in pores and pondin2
22 Required Storage (surface+ pores) Volume [0.75 x Line 101 642 cubic-feet
23 Required Footprint [Line 22 / Line 181 x 12 438 sq-ft
Footorint of the BMP
24 Area draining to the BMP 20,264 sq-ft
25 Adjusted Runoff Factor for drainage area (Refer to Appendix B.1 and B.2) 0.84
26 Minimum BMP Footprint [Line 24 x Line 25 x 0.031 514 sq-ft
27 Footprint of the BMP = Maximum~finimum(Line 21, Line 23), Line 26) 514 sq-ft
28 Used BMP Footprint 861 sq-ft
40
..
...
"
...
..
Appendix F: Biofiltration Standard and Checklist
considerations to provide for continued effectiveness of pollutant and flow control
functions.
'Ibe applicant shall provide documentation of compliance with each criterion in this checklist as part
of the project submittal. The right column of this checklist identifies the submittal information that
is recommended to document compliance with each criterion. Biofiltration BMPs that substantially
meet all aspects of Fact Sheets PR-1 or BF-1 should still use this checklist; however additional
documentation (beyond what is already required for project submittal) should not be required.
············· ··············. ································· .............. .
1. Biofiltration BMPs shall be allowed to be used only as described in the BMP
selection process based on a documented feasibility analysis .
Intent: This manual defines a specific prioritization of pollutant treatment BMPs, where BMPs that
retain water (retained includes evapotranspired, infiltrated, and/or ha.rvested and used) must be used
before considering BMPs that have a biofiltered discharge to the MS4 or surface waters. Use of a
biofiltration BMP in a manner in conflict with this prioritization (i.e., \vithout a feasibility analysis
justifying its use) is not permitted, regardless of the adequacy of the sizing and design of the system.
The project applicant has demonstrated that it
is not technically feasible to retain the fuU DCV
onsite.
Document feasibility analysis and findings in
project: submittalS\X-'QMP per Appendix C.
2. Biofiltration BMPs must be sized using acceptable sizing methods.
Intent: The MS4 Permit and this manual defines specitic sizing methods that must be used to size
biofiltration BMPs. Sizing of biofilt:rat:ion BTvfPs is a fundamental factor in the amount of storm
water that can be treated and also influences volume and pollutant retention processes.
The project applicant has demonstrated that
biofi1tration BMPs are sized to meet one of the
biofiltration sizing options available (Appendix
B.5).
Submit sizing worksheets (Appendix B.5) or
other equivalent documentation with the
SWQ?vfP.
3. Biofiltration BMPs must be sited and designed to achieve maximum feasible
infiltration and evapotranspiration.
Intent: Various decisions about BTvfP placement and design influence how much water is retained via
infiltration and evapotranspiration. The MS4 Permit requires that biofiltration BMPs achieve
maximum feasible retention (evapotranspiration and infiltration) of storm water volume .
F-3 February 2016
D
D
D
...
D
...
Appendix F: Biofiltration Standard and Checklist
The biofiltration B1'vfP is
maximum infiltration of runoff volume based
on the feasibility factors considered in site
planning efforts. It is also designed to
maximize evapotranspiration through the use
of amended media and plants (hofiltration
desii:,rns without amended media and plants may
be permissible; see Item 5).
For biofiltration BMPs categorized as "Partial
Infiltration Condition" the infiltration storage
depth in the biofiltration design has been
selected to drain in 36 hours ( + /-25'1'0) or an
alternative value shown to maximize infiltration
on the site.
For biofiltration BMP locations categorized as
"Partial Infiltration Condition," the infiltration
storage is over the entire bottom of the
biofiltration BMP footprint.
··························-···· ·········-····--···
For biofiltration BMP locations categorized as
"Partial Infiltration Condition," the sizing
factor used for the infiltration storage area is
not less than the minimum biofiltration BJ'v1P
sizing factors calculated using Worksheet B.5.1
to achieve 40'% average annual percent capture
within the B:MP or downstream of the BMP ..
An impermeable liner or other hydraulic
restriction layer is only used when needed to
avoid geotechnical and/ or subsurface
contamination issues in locations identified as
"No Infiltration Condition."
F-4
Document site planning and feasibility analyses
in S\VQMP per Section 5.4.
Included documentation estimated
infiltration rate per Appendix D; provide
calculations using Appendix B.4 and B.5 to
show that the infiltration storage depth meets
this criterion. Note, depths that are too shallow
or too deep may not be acceptable.
Document on plans that the infiltration storage
covers the entire bottom of the BMP (i.e., not
just underdrain trenches); or an equivalent
footprint elsewhere on the site.
Provide a table that compares the minimum
sizing factor per Appendix B.5 to the provided
sizing factor. Note: The infiltration storage area
could be a separate storage feature located
downstream of the biofiltration BMP, not
necessarily ·within the same footprint.
If using an impermeable liner or hydraulic
restriction layer, provide documentation of
feasibility findings per Appendix C that
recommend the use of this feature.
February 2016
..
..
""
..
..
Appendix F: Biofiltration Standard and Checklist
The use of "compact" biofiltration BMP
design2 is permitted only in conditions
identified as "No Infiltration Condition" and
where site-specific documentation
demonstrates that the use of larger footprint
biofiltration BJ\1Ps would be infeasible.
Provide documentation of feasibility findings
that recommend no infiltration is feasible.
Provide site-specific information to
demonstrate that a larger footprint biofiltration
BMP would not be feasible.
4. Biofiltration BMPs must be designed with a hydraulic loading rate to maximize
pollutant retention, preserve pollutant control processes, and minimize potential for
pollutant washout.
D
Intent: Vati.ous decisions about biofiltration BMP desii:,rn influence the degree to which pollutants arc
retained. The MS4 Permit requires that biofiltration BMPs achieve maximum feasible retention of
stonn water pollutants.
""""•••••••••••• .. ,._.,,. •••o•-'-•• ... .-a,•,
Media selected for the biofiltration BMP meets
minimum quality and material specifications
per 2016 City Storm Water Standards or
County LID 1Janual, including the maximum
allowable design filtration rate and minimum
thickness of media.
OR
Alternatively, for proprietary designs and
custom media mixes not meeting the media
specifications contained in the 2016 City Storm
Water Standards or County LID Manual. field
scale testing data are provided to demonstrate
that proposed media meets the pollutant
treatment performance criteria in Section F.1
below.
To the extent practicable, filtration rates are
out.let controlled (e.g., via an underdrain and
orifice/weir) instead of controlled by the
infiltration rate of the media.
Provide documentation that media meets the
specifications in 2016 City Storm \~'ater
Standards or County LID Manual.
Provide documentation of performance
information as described in Section F.1.
Include outlet control in designs or provide
documentation of why outlet control is not
practicable.
Compact biofiltration BMPs are defined as features with infiltration storage footprint less than the
minimum sizing factors required to achieve 40%, volume retention. Note that if a biofiltration Bl\'[P is
accompanied by an infiltrating area downstream that has a footprint equal to at least the minimum sizing
factors calculated using \X'orksheet B.5.1 assuming a partial infiltration condition, then it is not considered to
be a compact biofiltration BMP for the purpose of Item 4 of the checklist. For potential configurations with a
higher rate biofiltration BMP upstream of an larger footprint infiltration area, the BMP would still need to
comply with Item 5 of this checklist for pollutant treatment effectiveness .
F-5 February 2016
Appendix F: Biofiltration Standard and Checklist
The water surface drains to at least 12 inches
below the media surface within 24 hours from
the encl of storm event flow to preserve plant
health and promote healthy soil structure.
If nutrients are a pollutant of concern, design
of the biofiltration BMP follows nutrient-
sensitive design criteria.
Media ,rradation calculations or c•eotextile b h
selection calculations demonstrate that
migration of media between layers \Vill be
prevented and permeability will be preserved.
Include calculations to demonstrate that
drawdown rate is adequate.
Surface ponding drawclown time greater than
24-hours but less than 96 hours may be allmved
at the discretion of the City Engineer if
certified by a landscape architect or
agronomist.
Follow specifications nutrient sensitive
design in Fact Sheet BF-2. Or provide
alternative documentation that nutrient
treatment is addressed and potential for
nutrient release is minimized.
····-···· ....... --···· ......... ·····--"·· .. .
Follow specification for choking layer or
geotextile in Fact Sheet PR-1 or BF-1. Or
include calculations to demonstrate that
choking layer is appropriately specified.
5. Biofiltration BMPs must be designed to promote appropriate biological activity to
support and maintain treatment processes.
D
Intent: Biological processes are an important element of biofiltration performance and longevity .
... .-.-. .. -..--........ .
Plants have been selected to be tolerant of
project climate, design ponding depths and the
treatment media composition.
Plants have been selected to minimize irrigation
requirements.
Plant location and growth \Vil! not impede
expected long-term media filtration rates and
will enhance long term infiltration rates to the
extent possible.
If plants are not part of the biofiltration design,
other biological processes are supported as
needed to sustain treatment processes (e.g.,
biofilm in a subsurface flow wetland).
Provide documentation justifying plant
selection. Refer to the plant list in Appendix
F..20.
Provide documentation describing irrigation
requirements for establishment and long term
operation.
Provide documentation justifying plant
selection. Refer to the plant list in Appendix
E.20.
For biofiltration designs without plants,
describe the biological processes that will
support effective treatment and how they will
be sustained.
6. Biofiltration BMPs must be designed with a hydraulic loading rate to prevent
erosion, scour, and channeling '\vithin the BMP.
Intent: Erosion, scour, and/or channeling can disrupt treatment processes and reduce biofiltration
effectiveness.
F-6 February 2016
..
...
D
D
Appendix F: Biofiltration Standard and Checklist
Scour protection has been provided for both
sheet flow and pipe inflows to the BMP, where
needed.
Wbere scour protection has not been provided,
flows into and within the BMP arc kept to non-
erosive velocities.
For proprietary BMPs, the BMP is used in a
manner consistent with manufacturer
guidelines and conditiom of its third-party
cenification3 (i.e., maximum tributary area,
maximum inflow velocities, etc., as applicable).
Provide documentation of scour protection as
described in Fact Sheets PR-1 or BF-1 or
approved equivalent.
Provide documentation of design checks for
erosive velocities as described in Fact Sheets
PR-1 or BF-1 or approved equivalent.
Provide copy of manufacturer
recommendations and conditions of third-party
certification.
-·~~~~~~--~~~~ 7. Biofiltration BMP must include operations and maintenance design features and
planning considerations for continued effectiveness of pollutant and flow control
functions.
Intent: Biofiltration BMPs require regular maintenance in order provide ongoing function as
intended. Additionally, it is not possible to foresee and avoid potential issues as part of design;
therefore plans must be in place to correct issues if they arise.
The biofiltration BMP O&Nl plan describes
specific inspection activities, regular/periodic
maintenance activities and specific corrective
actions relating to scour, erosion, channeling,
media clogging, vegetation health, and inflow
and outflow structures.
Adequate site area and features have been
provided for BMP inspection and maintenance
access.
Include O&M plan \Vith project submittal as
described in Chapter 7.
Illustrate maintenance access routes, setbacks,
maintenance features as needed on project
water quality plans.
--~---------
D
For proprietary biofiltration BMPs, the B?vfP
maintenance plan is consistent with
manufacturer guidelines and conditions of its
third-party certification (i.e., maintenance
activities, frequencies) .
Provide copy of manufacturer
recommendations and conditions of third-party
certification.
3 Certifications or verifications issued by rhe \vashingron Technology Acceptance Protocol-Ecology program and the
New Jersey Corporation for Advanced Technology programs are typically accompanied by a set of guidelines regarding
appropriate design and maintenance conditions that would be consistent with the certification/verification
F-7 February 2016
t i i .,
1
Potential Sources of
Runoff Pollutants
IBJ A. Onsite storm drain
inlets
D Not Applicable
i
IBJ
• • j, &
2
Permanent Controls-Show on
Drawings
Locations of inlets.
.. ' • " "'
3 4
Permanent Controls-List in Table
and Narrative
Operational BMPs-lnclude in
Table and Narrative
IBJ Mark all inlets with the words "No / IBJ
Dumping! Flows to Bay" or similar.
See stencil template provided in I IBJ
Appendix I-4
Maintain and periodically repaint
or replace inlet markings.
Provide storm water pollution
prevention information to new
site owners, lessees, or operators.
IBJ See applicable operational BMPs
in Fact Sheet SC-44, "Drainage
System Maintenance," in the
CASQA Storm Water Quality
Handbooks at
\vww. casqa.org /resources/bmp-
handbooks /municipal-bmp-
handbook.
IBJ Include the following in lease
agreements: "Tenant shall not
allow anyone to discharge
anything to storm drains or to
store or deposit materials so as to
create a potential discharge to
storm drains."
og
D
w
D
(8:)
1
Potential Sources of
Runoff Pollutants
B. Interior floor
drains and elevator
shaft sump pumps
Not Aeelicable
C. Interior parking
garages
Not Applicable
D1. Need for future
indoor & structural
pest control
D Not Applicable
2
Permanent Controls-Show on
Drawings
3
Permanent Controls-List in Table
and Narrative
D State that interior floor drains and
elevator shaft sump pumps will be
plumbed to sanitary sewer.
D State that parking garage floor
drains will be plumbed to the
sanitary sewer.
4
Operational BMPs-Include in
Table and Narrative
og Inspect and maintain drains to
prevent blockages and overflow.
ijJ Inspect and maintain drains to
prevent blockages and overflow.
(8:) Note building design features that I (8:)
discourage entry of pests.
Provide Integrated Pest
Management information to
owners, lessees, and operators.
t i ~ .. ,i
1
Potential Sources of
Runoff Pollutants
[ID D2. Landscape/
Outdoor Pesticide
Use
D Not Applicable
t • • ..
2
Permanent Controls-Show on
Drawings
[ID
[ID
[ID
Show locations of existing
trees or areas of shrubs and
ground cover to be
undisturbed and retained.
Show self-retaining landscape
areas, if any.
Show storm water treatment
facilities.
., ., ti
3
Permanent Controls-List in Table and
Narrative
State that final landscape plans will I [ID
accomplish all of the following.
[ID Preserve existing drought tolerant I [ID
trees, shrubs, and ground cover to the
maximum extent possible.
[ID Design landscaping to m1mm1ze
irrigation and runoff, to promote
surface infiltration where appropriate,
and to minimize the use of fertilizers
and pesticides that can contribute to
storm water pollution.
[ID Where landscaped areas are used to I [ID
retain or detain storm water, specify
plants that are tolerant of periodic
saturated soil conditions.
[ID Consider using pest-resistant plants,
especially adjacent to hardscape.
[ID To ensure successful establishment,
select plants appropriate to site soils,
slopes, climate, sun, wind, rain, land
use, air movement, ecological
consistency, and plant interactions.
4
Operational BMPs-lnclude in
Table and Narrative
Maintain landscaping using
minimum or no pesticides.
See applicable operational
BMPs in Fact Sheet SC-41,
"Building and Grounds
Maintenance," in the CASQA
Storm Water Quality
Handbooks at
W\VW.casqa.org/resource!,/bmp
-handbooks/municipal-bmp-
handbook.
Provide IPM information to
new owners, lessees and
operators.
1
Potential Sources of
Runoff Pollutants
D E. Pools, spas,
ponds, decorative
fountains, and other
water features.
131 Not Applicable
D F. Food service
~ Not Applicable
D
2
Permanent Controls-Show on
Drawings
Show location of water feature
and a sanitary sewer cleanout in
an accessible area within 10 feet.
D For restaurants, grocery stores,
and other food service
operations, show location
(indoors or in a covered area
outdoors) of a floor sink or other
area for cleaning floor mats,
containers, and equipment.
D On the drawing, show a note that
this drain will be connected to a
grease interceptor before
discharging to the sanitary sewer.
3
Permanent Controls-List in Table
and Narrative
D If the local municipality requires
pools to be plumbed to the sanitary
sewer, place a note on the plans and
state in the narrative that this
connection will be made according to
local requirements.
D Describe the location and features of
the designated cleaning area.
D Describe the items to be cleaned in
this facility and how it has been sized
to ensure that the largest items can be
accommodated.
4
Operational BMPs-Include
in
Table and Narrative
D See applicable operational
BMPs in Fact Sheet SC-72,
"Fountain and Pool
Maintenance," in the CASQA
Storm Water Quality
Handbooks at
www.casga.org/ rcsources/bm
p-hanclbooks/municipal-
bmp-handboo k.
1
Potential Sources
of
IXI G. Refuse areas
D Not Applicable
2
Permanent Controls-Show
on Drawings
12!1 Show where site refuse and
recycled materials will be
handled and stored for
pickup. See local municipal
requirements for sizes and
other details of refuse areas.
D If dumpsters or other
receptacles are outdoors,
show how the designated
area will be covered, graded,
and paved to prevent run-
on and show locations of
berms to prevent runoff
from the area. Also show
how the designated area will
be protected from wind
dispersal.
D Any drains from dumpsters,
compactors, and tallow bin
areas must be connected to
a grease removal device
before discharge to sanitary
sewer.
3
Permanent Controls-List
in Table and Narrative
IXI State how site refuse will
be handled and provide
supporting detail to what
is shown on plans.
IXI State that signs will be
posted on or near
dumpsters with the
words "Do not dump
hazardous materials
here" or similar.
4
Operational BMPs-Include in
Table and Narrative
IXI State how the following will be implemented:
Provide adequate number of receptacles. Inspect
receptacles regularly; repair or replace leaky
receptacles. Keep receptacles covered.
Prohibit/prevent dumping of liquid or hazardous
wastes. Post "no hazardous materials" signs. Inspect
and pick up litter daily and clean up spills
immediately. Keep spill control materials available
on-site. See Fact Sheet SC-34, "Waste Handling and
Disposal" in the CASQA Storm Water Quality
Handbooks at v,'\vw.casqa.org/resources/bmp-
handbooks/municipal-bmp-handbook.
1
Potential Sources of
Runoff Pollutants
D H. Industrial
processes.
IXI Not Applicable
D I. Outdoor storage
of equipment or
materials. (See rows J
and K for source
control measures for
vehicle cleaning,
repair, and
maintenance.)
!XI Not Applicable
2
Permanent Controls-Show on
Drawings
D
D
D
Show process area.
Show any outdoor storage
areas, including how materials
will be covered. Show how
areas will be graded and
bermed to prevent run-on or
runoff from area and
protected from wind dispersal.
Storage of non-hazardous
liquids must be covered by a
roof and/ or drain to the
sanitary sewer system, and be
contained by berms, dikes,
liners, or vaults.
D Storage of hazardous materials
and wastes must be in
compliance with the local
hazardous materials ordinance
and a Hazardous Materials
Management Plan for the site.
"
3
Permanent Controls-List in Table and
Narrative
D If industrial processes are to be located
onsite, state: "All process activities to be
performed indoors. No processes to
drain to exterior or to storm drain
system."
D Include a detailed description of
materials to be stored, storage areas, and
structural features to prevent pollutants
from entering storm drains.
Where appropriate, reference
documentation of compliance with the
requirements of local Hazardous
Materials Programs for:
• Hazardous Waste Generation
• Hazardous Materials Release
Response and Inventory
• California Accidental Release
Prevention Program
• Aboveground Storage Tank
• Uniform Fire Code Article 80
Section 103(b) & (c) 1991
• Underground Storage Tank
4
Operational BMPs-Include
in Table and Narrative
Table and Narrative
D See Fact Sheet SC-10, "Non-
Storm Water Discharges" in
the CASQA Storm Water
Quality Handbooks at
https: // '.V\Vw.casqa.org/rcsou
re~ /bmn~lumdlli>oks.
D See the Fact Sheets SC-31,
"Outdoor Liquid Container
Storage" and SC-33,
"Outdoor Storage of Raw
Materials" in the CASQA
Storm Water Quality
Handbooks at
www.casqa.org/rcsourccs/bm
p-handbooks /municipal-bmp-
handbook.
.. i ~
1
Potential Sources of
Runoff Pollutants
0 J. Vehicle and
Equipment Cleaning
IXI Not Applicable
t "' i
2
Permanent Controls-Show on Drawings
0 Show on drawings as appropriate:
(1) Commercial/industrial facilities having
vehicle / equipment cleaning needs must
either provide a covered, bermed area for
washing act1v1t1es or discourage
vehicle/ equipment washing by removing
hose bibs and installing signs prohibiting such
uses.
(2) Multi-dwelling complexes must have a
paved, bermed, and covered car wash area
(unless car washing is prohibited onsite and
hoses are provided with an automatic shut-
off to discourage such use).
(3) Washing areas for cars, vehicles, and
equipment must be paved, designed to
prevent run-on to or runoff from the area,
and plumbed to drain to the sanitary sewer.
(4) Commercial car wash facilities must be
designed such that no runoff from the facility
is discharged to the storm drain system.
Wastewater from the facility must discharge
to the sanitary sewer, or a wastewater
reclamation system must be installed.
3
Permanent Controls-List in
Table and Narrative
0 If a car wash area is not
provided, describe measures
taken to discourage onsite
car washing and explain how
these will be enforced.
4
Operational BMPs-Include in
Table and Narrative
Describe operational measures to
implement the following (if
applicable):
0 Washwater from vehicle and
equipment washing operations
must not be discharged to the
storm drain system.
0 Car dealerships and similar
may rinse cars with water
only.
0 See Fact Sheet SC-21,
"Vehicle and Equipment
Cleaning," in the CASQA
Storm Water Quality
Handbooks at
www.casqa.org/resources /bm
p-handbooks /municipal-bmp-
handbook.
it " •
1
Potential Sources of
Runoff Pollutants
0 K.
Vehicle/Equipment
Repair and
Maintenance
~ Not Applicable
0
0
0
i. i! Ii "
2
Permanent Controls-Show on
Drawings
Accommodate all vehicle
equipment repair and
maintenance indoors. Or
designate an outdoor work area
and design the area to protect
from rainfall, run-on runoff, and
wind dispersal.
Show secondary containment for
exterior work areas where motor
oil, brake fluid, gasoline, diesel
fuel, radiator fluid, acid-
containing batteries or other
hazardous materials or hazardous
wastes are used or stored. Drains
must not be installed within the
secondary containment areas.
Add a note on the plans that
states either (1) there are no floor
drains, or (2) floor drains are
connected to wastewater
pretreatment systems prior to
discharge to the sanitary sewer
and an industrial waste discharge
permit will be obtained.
l, "' ~
3
Permanent Controls-List in
Table and Narrative
0 State that no vehicle repair or
maintenance will be done
outdoors, or else describe the
required features of the
outdoor work area.
0 State that there are no floor
drains or if there are floor
drains, note the agency from
which an industrial waste
discharge permit will be
obtained and that the design
meets that agency's
requirements.
0 State that there are no tanks,
containers or sinks to be used
for parts cleaning or rinsing
or, if there are, note the
agency from which an
industrial waste discharge
permit will be obtained and
that the design meets that
agency's requirements.
ii t "
4
Operational BMPs-Include in
Table and Narrative
In the report, note that all of the following
restrictions apply to use the site:
0 No person must dispose of, nor permit
the disposal, directly or indirectly of
vehicle fluids, hazardous materials, or
rinsewater from parts cleaning into
storm drains.
0 No vehicle fluid removal must be
performed outside a building, nor on
asphalt or ground surfaces, whether
inside or outside a building, except in
such a manner as to ensure that any
spilled fluid will be in an area of
secondary containment. Leaking
vehicle fluids must be contained or
drained from the vehicle immediately.
0 No person must leave unattended drip
parts or other open containers
containing vehicle fluid, unless such
containers are in use or in an area of
secondary containment.
"'
1
Potential Sources of
Runoff Pollutants
0 L. Fuel Dispensing
Areas
Ill Not Applicable
•
2
Permanent Controls-Show on
Drawings
0 Fueling areas 16 must have
impermeable floors (i.e., portland
cement concrete or equivalent smooth
impervious surface) that are (1) graded
at the minimum slope necessary to
prevent ponding; and (2) separated
from the rest of the site by a grade
break that prevents run-on of storm
water to the MEP.
0 Fueling areas must be covered by a
canopy that extends a minimum of ten
feet in each direction from each
pump. [Alternative: The fueling area
must be covered and the cover's
minimum dimensions must be equal
to or greater than the area within the
grade break or fuel dispensing area 1.]
The canopy [or cover] must not drain
onto the fueling area.
3
Permanent Controls-List
in Table and Narrative
4
Operational BMPs-Include in
Table and Narrative
0 The property owner must dry sweep
the fueling area routinely.
0 See the Business Guide Sheet,
"Automotive Service-Service
Stations" in the CASQA Storm
Water Quality Handbooks at
https://www.casqa.org/resources/b
mp-handbooks.
16 The fueling area must be defined as the area extending a minimum of 6.5 feet from the comer of each fuel dispenser or the length at which the hose and nozzle assembly may be
operated plus a minimum of one foot, whichever is greater.
.. •
1
Potential Sources of
Runoff Pollutants
M. Loading Docks
~ Not Applicable
ii " t ..
2
Permanent Controls-Show on
Drawings
D Show a preliminary design for the
loading dock area, including
roofing and drainage. Loading
docks must be covered and/ or
graded to minimize run-on to and
runoff from the loading area. Roof
downspouts must be positioned to
direct storm water away from the
loading area. Water from loading
dock areas should be drained to
the sanitary sewer where feasible.
Direct connections to storm
drains from depressed loading
docks are prohibited.
D Loading dock areas draining
directly to the sanitary sewer must
be equipped with a spill control
valve or equivalent device, which
must be kept closed during
periods of operation.
D Provide a roof overhang over the
loading area or install door skirts
(cowling) at each bay that enclose
the end of the trailer.
¥
3
Permanent
Controls-List in
i it I. i
4
Operational BMPs-Include in
Table and Narrative
D Move loaded and unloaded items indoors as
soon as possible.
D See Fact Sheet SC-30, "Outdoor Loading and
Unloading," in the CASQA Storm Water
Quality Handbooks at
\V\VW.casqa.org/resourccs/bmp-
handbooks/municipal-bmp-handbook.
I: l .. ,i,
1
Potential Sources of
Runoff Pollutants
D N. Fire Sprinkler
Test Water
Iii Not Applicable
0. Miscellaneous Drain
or \'v'ash Water
D Boiler drain lines
D Condensate drain
lines
D Rooftop
equipment
D Drainage sumps
D Roofing, gutters,
and trim
~ Not Applicable
l t
2
Permanent Controls-
Show on Drawings
D
;, i, ' l,
3
Permanent Controls-List in Table and
Narrative
!<
Provide a means to drain fire sprinkler test water
to the sanitary sewer.
D Boiler drain lines must be directly or indirectly
connected to the sanitary sewer system and may
not discharge to the storm drain system.
D Condensate drain lines may discharge to
landscaped areas if the flow is small enough that
runoff will not occur. Condensate drain lines
may not discharge to the storm drain system.
D Rooftop mounted equipment with potential to
produce pollutants must be roofed and/ or have
secondary containment.
D Any drainage sumps onsite must feature a
sediment sump to reduce the quantity of
sediment in pumped water.
D Avoid roofing, gutters, and trim made of copper
or other unprotected metals that may leach into
runoff.
" i
4
Operational BMPs-Include in
Table and Narrative
D See the note in Fact Sheet SC-
41, "Building and Grounds
Maintenance," in the CASQA
Storm Water Quality
Handbooks at
www.casqa.org I resources /bm
p-handbooks/municipal-bmp-
handbook
l II £ l i
1
Potential Sources of
Runoff Pollutants
!XI P.
sidewalks,
parking lots.
D Not Applicable
Plazas,
and
II. i & j II. j t
2
Permanent Controls-Show on
Drawings
t. ,.,
3
Permanent Controls-List in
Table and Narrative
/j, it
4
Operational BMPs-lnclude in
Table and Narrative
C!I Plazas, sidewalks, and parking lots must
be swept regularly to prevent the
accumulation of litter and debris.
Debris from pressure washing must be
collected to prevent entry into the
storm drain system. Washwater
containing any cleaning agent or
degreaser must be collected and
discharged to the sanitary sewer and
not discharged to a storm drain.
ATTACHMENT 2
Structural BMP Maintenance Information
..
42
Attachment 2a
Structural BMP Maintenance Thresholds and Actions
..
..
43
PRIVATE TREATMENT CONTROL BMP
OPERATION AND MAINTENANCE VERIFICATION FORM
BIORETENTION FACILITIES, VEGETATED SWALES & HIGHER RATE
BIOFILTERS
1. Transcribe the following information from your notification letter and make corrections as necessary:
Permit No.:
BMP Location:
Responsible Party:
Phone Number: ( Email:
Responsible Party Address:
Number Street Name & Suffix City/Zip D Check here for Address or phone number change
2. Using the Table below, please describe the inspections and maintenance activities that have been conducted during
the fiscal year (July 1 -June 30), and date(s) maintenance was performed. Under "Results of Inspection," indicate
whether maintenance was required based on each inspection, and if so, what type of maintenance. If maintenance
was required, provide the date maintenance was conducted and a description of the maintenance. REFER TO
" THE BACK OF THIS SHEET FOR MORE INFORMATION DESCRIBING TYPICAL
MAINTENANCE IND/CA TORS AND MAINTENANCE ACTIVITIES. If no maintenance was required
based on the inspection results, state "no maintenance required."
'""
Results of
Inspection: Date Maintenance Completed and
Date Work needed? Description of Maintenance Conducted
What To Look For? Inspected (Yes/No)
Accumulation of
Sediment, Litter,
Grease
Standing Water
Erosion
Overgrown
Vegetation
Poor Vegetation
Establishment
Structural Damage
3. Attach copies of available supporting documents (photographs, copies of maintenance contracts, and/or
maintenance records).
4. Sign the bottom of the form and return to:
Signature of Responsible Party
County of San Diego Watershed Protection Program
Treatment Control BMP Tracking
5201 Ruffin Road, Suite P, MS 0326
San Diego, CA 92123 OR
Email: Watersheds@sdcounty.ca.gov
Print Name Date
..
PRIVATE TREATMENT CONTROL BMP
OPERATION AND MAINTENANCE VERIFICATION FORM
BIORETENTION FACILITIES, VEGETATED SWALES & HIGHER RATE
BIOFIL TERS-SIDE 2
This guide sheet provides general indicators for maintenance only and for a wide array of treatment
control BMPs. Your developer prepared maintenance plans specifically for your treatment control
BMP as an appendix to the Stormwater Management Plan. Also, if you have a manufactured
structure, please refer to the manufacturer's maintenance instructions.
Biofilters include the following :
D Vegetated Filter Strip/Swale D Bioswale D Bioretention Facility D Planter Boxes
D Manufactered Higher-Flow-Rate Biofilters, such as Tree-Pit-Style Units.
Routine maintenance is needed to ensure that flow is unobstructed, that erosion is prevented, and that soils are held
together by plant roots and are biologically active. Typical maintenance consists of the following:
Bioretention BMPs Inspection and Maintenance Checklist
Typical Maintenance Indicators Typical Maintenance Actions
Accumulation of sediment (over 2 inches deep or Remove and properly dispose of accumulated materials,
covers vegetation), litter, or debris without damage to the vegetation. Confirm that soil is not
clogging and that the area drains after a storm event. Till
or replace soil as necessary.
Poor vegetation establishment Ensure vegetation is healthy and dense enough to provide
filtering and to protect soils from erosion. Replenish mulch
as necessary (if less than 3 inches deep), remove fallen
leaves and debris, prune large shrubs or trees, and mow
turf areas.
Overgrown vegetation-woody vegetation not part Mow or trim as appropriate, but not less than the design
of design is present and grass excessively tall height of the vegetation (typically 4-6 inches for grass).
(greater than 10 inches) Confirm that irrigation is adequate and not excessive and
that sprays do not directly enter overflow grates. Replace
dead plants and remove noxious and invasive weeds.
Erosion due to concentrated irriQation flow Repair/re-seed eroded areas and adjust the irriQation.
Erosion due to concentrated stormwater runoff flow Repair/re-seed eroded areas and make appropriate
corrective measures such as adding erosion control
blankets, adding stone at flow entry points, or re-grading
where necessary.Remove obstructions and sediment
accumulations so water disperses.
Standing water (BMP not draining) . If mosquito Where there is an underdrain, such as in planter boxes
larvae are present and persistent, contact the San and manufactured biofilters, check the underdrain piping
Diego County Vector Control Program at (858) 694-to make sure it is intact and unobstructed. Abate any
2888. Mosquito larvicides should be applied only potential vectors by filling holes in the ground in and
when absolutely necessary and then only by a around the biofilter facility and by insuring that there are
licensed individual or contractor. no areas where water stands longer than 96 hours
followinQ a storm .
Obstructed inlet or outlet structure Clear obstructions.
Damage to structural components such as weirs, Repair or replace as applicable.
inlet, or outlet structures
Before the wet season and after rain events: remove Where cisterns are part of the system
sediment and debris from screens and overflow
drains and downspouts; ensure pumps are
functioning, where applicable; check integrity of
mosquito screens; and; check that covers are
properly seated and locked.
For manufactured high-flow-rate biofilters, see
manufacturer's maintenance guidelines
~ BIORETENTION FACILITIES
These facilities remove pollutants primarily by filtering runoff slowly through aerobic, biologically
active soil. Routine maintenance is needed to ensure that flow is unobstructed, that erosion is
prevented, and that soils are held together by plant roots and are biologically active. Typical
maintenance consists of the following:
•
•
•
•
•
•
•
Inspect inlets for channels, exposure of soils, or other evidence of erosion. Clear any
obstructions and remove any accumulation of sediment. Examine rock or other material
used as a splash pad and replenish if necessary.
Inspect outlets for erosion or plugging .
Inspect side slopes for evidence of instability or erosion and correct as necessary .
Observe the surface of bioretention facility soil for uniform percolation throughout. If
portions of the bioretention facility do not drain within 24 hours after the end of a storm,
the soil should be tilled and replanted. Remove any debris or accumulations of sediment.
Confirm that check dams and flow spreaders are in place and level and that rivulets and
channelization are effectively prevented.
Examine the vegetation to ensure that it is healthy and dense enough to provide filtering
and to protect soils from erosion. Replenish mulch as necessary, remove fallen leaves and
debris, prune large shrubs or trees, and mow turf areas. When mowing, remove no more
than 1/3 height of grasses. Confirm that irrigation is adequate and not excessive and that
sprays do not directly enter overflow grates. Replace dead plants and remove noxious and
invasive vegetation.
Abate any potential vectors by filling holes in the ground in and around the bioretention
facility and by insuring that there are no areas where water stands longer than 48 hours
following a storm. If mosquito larvae are present and persistent, contact the San Diego
County Vector Control Program for information and advice. Mosquito larvicides should
be applied only when absolutely necessary and then only by a licensed individual or
contractor.
Attachment 2b
Draft Maintenance Agreement
I. Purpose and Scope
This section was prepared based on the Chapter 7 of City of Carlsbad BMP Design Manual The
goal is to insure that the Project proponent accepts responsibility for all facilities maintenance,
repair, and replacement from the time they are constructed until the ownership and maintenance
responsibilities is formally transferred to the new owner. Facilities shall be maintained in perpetuity
and comply with the City's self-inspection, reporting, and verification requirements.
II. Inspection, Maintenance Log and Self-Verification Forms
Fill the forms on the following pages for each BMP using the maintenance schedule here and the
inspection-maintenance checklists in Section VII. These forms shall be signed by the responsible
party and retained for at least (5) years. Use the DMA Exhibit for the location of BMPs. (Make
duplicate copies of these forms and fill out those, not the original ones.)
Ill. Updates, Revisions and Errata
This maintenance plan is a living document and based on the changes made by maintenance
personnel, such as replacement of mechanical equipments, addition maintenance procedure
shall be added and maintenance plan shall be kept up to date.
Please add the revisions and updates to the maintenance plan to this section if any, these
revisions maybe transmitted to the City at any time. However, at a minimum, updates to the
maintenance plan must accompany the annual inspection report.
IV. Introduction
The project proposes the development of a multi-unit apartment complex with underground
parking. Proposed drainage improvements consist of two (2) biofiltration BMPs to provide
stormwater treatment and maintain the pre-developed runoff characteristics. The project drains
to one (1) Point of Compliance (POC) located to the southwest corner of the project site.
44
"
..
V. Responsibility for Maintenance
A. General
Edmond T. Shehab will enter into a Stormwater Facilities Maintenance Agreement (SWFMA)
with the City of Carlsbad to maintain designated facilities herein this section for the 800 Grand
Condominiums.
The SWFMA will serve as the mechanism to ensure that proper inspection and maintenance
is done in an efficient and timely manner.
Responsible Party
Edmond T. Shehab
800 Grand MMKLC, LLC
800 Grand Avenue, Suite c16
Carlsbad, CA 92008
858-342-9725
Edmond T. Shehab will have the direct responsibility for maintenance of Stormwater controls.
A Home Owner's Association (HOA) shall be formed, or establish another mechanism to the
satisfaction of the City. Funding for the maintenance activities shall be provided by Edmond
T. Shehab, the HOA, or other mechanism to the satisfaction of the City.
Whenever the property is sold and whenever designated individual change, immediately the
updated contact information must be provided to the City of Carlsbad.
B. Staff Training Program
Staff training and education program shall be carried out twice a year, once prior to the rainy
season (October 151) and once during the early dry season (April 301h).
The inspection and maintenance training program consists of the operation and function of
the bioretention basins. Please refer to the sections VI and VI I for fact sheets and checklists.
It is the responsibility of Edmond T. Shehab to convey the maintenance and inspection
information to the employees. Maintenance personnel must be qualified to properly maintain
stormwater management facilities. Inadequately trained personnel can cause additional
problems resulting in additional maintenance costs.
C. Records
Edmond T. Shehab shall retain education, inspection, and maintenance forms and documents
for at least five (5) years.
45
...
..
D. Safety
Keep safety considerations at the forefront of inspection procedures at all times. Likely
hazards should be anticipated and avoided. Never enter a confined space (outlet structure,
manhole, etc) without proper training or equipment. A confined space should never be
entered without at least one additional person present.
If a toxic or flammable substance is discovered, leave the immediate area and contact the
local Sheriff at 911.
Potentially dangerous (e.g., fuel, chemicals, hazardous materials) substances found in the
areas must be referred to the local Sheriff's Office immediately for response by the Hazardous
Materials Unit. The emergency contact number is 911.
Vertical drops may be encountered in areas located within and around the facility. Avoid
walking on top of retaining walls or other structures that have a significant vertical drop. If a
vertical drop is identified within the pond that is greater than 48" in height, make the
appropriate note/comment on the maintenance inspection form.
VI. Summary of Drainage Areas and Stormwater Facilities
A. Drainage Areas
Storm water runoff from the proposed project site is routed to a single POC located at the
southwest of the project site. The proposed drainage pattern will be similar to the existing
drainage pattern with some modifications to incorporate the Best Management Practices
(BMPs) into the project design to mimic the impacts on storm water runoff and quality. Runoff
from the developed project site is drained to two (2) onsite biofiltration BMPs (WQ-BMPs) for
water quality purposes (the project is not subject to hydromodification requirements). Once
flows are routed via the proposed WQ-BMPs, all flows are then conveyed via storm drain to
the aforementioned POC.
DMA 1 A and DMA 1 B encompasses runoff from the proposed building. Roof drains will collect
runoff and discharge into proposed biofiltration basins, BMP 1 A and BMP 1 B, located between
the southerly property line and the proposed building. The biofiltration basins will provide
stormwater treatment and flow detention. Treated water will discharge via storm drain pipes
to proposed curb outlets onto Grand Avenue.
Runoff from the concrete sidewalk area will intercepted by a private storm drain system and
conveyed to an underground vault located underneath the garage. The underground vault
will be sized as a cistern to store the volume from a 100 year storm event. Trench drains
within the underground garage will also collect miscellaneous storm water runoff and will
convey flow to the underground vault. A sump pump located in a pump room will pump storm
water runoff to the biofiltration basins for treatment based at a maximum of 0.03 cubic feet per
second (13.5 gallons per minute). For stormwater runoff greater than a 100-year storm event,
a backup pump will start automatically to empty the underground vault.
46
...
.,
..
Small areas in the southern portion of the project will gravity flow towards Grand Avenue. The
landscape areas will be designed with native and/or drought tolerant species. These area are
considered Self-mitigating DMAs per Section 5.2.1 of the BMP DM and illustrated on the OMA
Exhibit.
The concrete sidewalk areas that gravity flow towards Grand Avenue are considered De
Minimis DMAs per Section 5.2.1 of the BMP DM. These impervious areas are less than 250
square feet and are not considered to be a significant contributor of pollutants.
B. Treatment and Flow-Control Facilities
Two (2) WQ-BMP biofiltration basins with no infiltration are located within the project site and
are responsible for handling water quality requirements for the project site. In developed
conditions, the basins will have a surface depth of 1.2 feet. The basins will be configured with
a 10-inch ponding layer above the surface for storage volume, an 18-inch layer of amended
soil below the surface, and a 10-inch gravel storage layer below the amended soil layer to
accommodate the French drain system. Below the gravel layer the basins are lined to prevent
infiltration into the underlying soil. Flows will discharge from the basins via perforated
underdrain pipe within the gravel layer to the receiving storm drain system. A riser structure
will be constructed within the BMPs with an emergency overflow set 10-inches above the
bottom of the basin, such that peak flows can be safely discharged to the receiving storm
drain system.
See the OMA Exhibit for the location of BMPs.
The bioretention basins are designed to treat and detain runoff. Pollutants are removed as
the runoff passes through the soil layer and the underlying layer of gravel or drain rock. There
will be an overflow outlet, which will convey flows that exceed the capacity of the basins. The
basins for this Project are sized for pollutant control only, based on the City of Carlsbad BMP
Design Manual.
VII. Facility Documentation
Please see the following pages regarding the BMPs details and maintenance fact sheets.
VIII. Maintenance Schedule and Checklist
Fill out the Checklists in the following pages for each BMP. The Required Maintenance activities
are at the end of this section. At the discretion of the Project proponent, a qualified Stormwater
company may be hired to perform the required inspection and maintenance and provide
necessary reports .
47
Bio Retention Basin Inspection & Maintenance Checklist
I Property:
Property Owner:
,, Date of Inspection: lnspector(s) Name:
Address: ,, Basin Location: OMA#_ Phone:
Type of Inspection 0Monthly D pre-wet season 0Atter heavy runoff
0End of wet season Oother:
( 1" or greater)
Y=Yes N=No MR=Maintenance Required NA= Not Applicable
Vegetation & Irrigation:
§Vegetation is dead or diseased
Vegetation & Irrigation systems in good condition
Overgrown D Neat and orderly in appearance
Required Maintenance:
·•
Soil:
0Too deep or too shallow
(the distance from the top of mulch to the top of riser pipe shall be 4")
Required Maintenance:
..
Paae1of3
.•
..
Mulch:
§ Missing or Patchy in Appearance
Depth of mulch layer less than 3-in
Areas of Bare earth
Required Maintenance: ----------------------------------------------------------------------------------------~
Sediment, Trash & Debris:
0Accumulated sediment, trash,and debris present D Drain time exceeds 4 hours
Required Maintenance: ----------------------------------------------------------------------------------------~
Clogs: §Soil too deep or too shallow
accumulated sediment, trash and debris
Drain time more than 5 days after rainfall
Required Maintenance: ----------------------------------------------------------------------------------------~
Structural Components:
Flow to basin is impeded
inflow pipes or downspouts are cloged/damaged
damaged splash/rock blocks
Over flow pipe in damaged or cloged
Underdrain pipes cloged or damaged
Planter is cracked, leaking or falling apart
Pa e 2 of 3
Inspector Signature: _________ _ Date: _______ _
Inspector Signature: _________ _ Date: _______ _
The basin shall be drained within 5 days after each storm event, standing water
for more than 5 days will cause mosquito breeding, contact County of San Diego Vector Control
Program at (858) 694-2888.
** The Responsible Party shall retail the maintenance/inspection records for a minimum of 5 years
from the date of maintenance.The records shall be made available to the County of San Diego for
inspection upon re uest at an time. Pa e 3of 3
... BIORETENTION FACILITIES
These facilities remove pollutants primarily by filtering runoff slowly through aerobic, biologically
active soil. Routine maintenance is needed to ensure that flow is unobstructed, that erosion is
prevented, and that soils are held together by plant roots and are biologically active. Typical
maintenance consists of the following:
•
•
•
•
•
•
•
Inspect inlets for channels, exposure of soils, or other evidence of erosion. Clear any
obstructions and remove any accumulation of sediment. Examine rock or other material
used as a splash pad and replenish if necessary.
Inspect outlets for erosion or plugging .
Inspect side slopes for evidence of instability or erosion and correct as necessary .
Observe the surface of bioretention facility soil for uniform percolation throughout. If
portions of the bioretention facility do not drain within 24 hours after the end of a storm,
the soil should be tilled and replanted. Remove any debris or accumulations of sediment.
Confirm that check dams and flow spreaders are in place and level and that rivulets and
channelization are effectively prevented.
Examine the vegetation to ensure that it is healthy and dense enough to provide filtering
and to protect soils from erosion. Replenish mulch as necessary, remove fallen leaves and
debris, prune large shrubs or trees, and mow turf areas. When mowing, remove no more
than 1/}height of grasses. Confirm that irrigation is adequate and not excessive and that
sprays do not directly enter overflow grates. Replace dead plants and remove noxious and
invasive vegetation.
Abate any potential vectors by filling holes in the ground in and around the bioretention
facility and by insuring that there are no areas where water stands longer than 48 hours
following a storm. If mosquito larvae are present and persistent, contact the San Diego
County Vector Control Program for information and advice. Mosquito larvicides should
be applied only when absolutely necessary and then only by a licensed individual or
contractor.
ATTACHMENT 3
City standard Single Sheet BMP (SSBMP) Exhibit
48
MAINTENANCE INDICATORS AND ACTIONS FOR
BIOFILTRATION BMPS
TYPICAL MAINTENANCE IND/CA TORS TYPICAL MAINTENANCE ACTIONS
ACCUMULA TTON OF SEDIMENT (OVER REMOVE AND PROPERLY DISPOSE OF
2 INCHES DEEP OR COVERS ACCUMULATED MATERIALS WITHOUT
VEGETA TTON), LITTER, OR DEBRIS DAMAGE TO THE VEGETA TTON.
CONRRM THAT SOIL JS NOT
CLOGGING AND THAT THE AREA
DRAINS AFTER STORM EVENT. TILL
OR REPLACE SOIL AS NECESSARY.
POOR VEGETA TTON ESTABLISHMENT ENSURE VEGETA TTON JS HEAL THY
AND DENSE ENOUGH TO PROVIDE
FILTERING AND TO PROTECT SOILS
FROM EROSION. REPLENISH MULCH
AS NECESSARY (IF LESS THAN 3
INCHES DEEP), REMOVE FALLEN
LEAVES AND DEBRIS, PRUNE LARGE
SHRUBS OR TREES, AND MOW TURF
AREAS.
OVERGROWN VEGETA TTON-WOODY MOW DR TRIM AS APPRDPRIA TE,
VEGETA TTON NOT PART OF DESIGN BUT NOT LESS THAN THE DESIGN
IS PRESENT AND GRASS HEIGHT OF THE VEGETATION
EXCESS/VEL Y TALL (GREATER THAN (TYPICALLY 4-6 INCHES FDR
10 INCHES) GRASS). CONFIRM THAT IRRIGA TIDN
IS ADEQUATE AND NOT EXCESSIVE
AND THAT SPRAYS DD NOT
DIRECTLY ENTER OVERFLOW
GRATES. REPLACE DEAD PLANTS
AND REMOVE NOXIOUS AND
INVASIVE WEEDS.
EROSION DUE TO CONCENmA TED REPAIR/RE -SEED ERODED AREAS
/RR/GA TION FLOW AND ADJUST THE IRRIGA TIDN.
EROSION DUE TO CONCENmA TED REPAIR/RE-SEED 'ERODED AREAS
STORM WATER RUNOFF FLOW AND MAKE APPRDPRIA TE
CORRECTIVE MEASURES SUCH AS
ADDING EROSION CONTROL
BLANKETS, ADDING STONE AT
ENTRY POINTS, DR RE -GRADING
WHERE NECESSARY. REMOVE
OBSTRUCTIONS AND SEDIMENT
ACCUMULA TIDNS SD WATER
DISPERSES.
STANDING WATER (BMP NOT WHERE THERE JS AN UNDERDRAIN,
DRAINING). IF MOSQUITO LARVAE SUCH AS IN PLANTER BOXES AND
ARE PRESENT AND PERSISTENT, MANUFACTURED BIOFILTERS, CHECK
CONTACT THE SAN DIEGO VECTOR THE UNDERDRAIN PIPING TO MAKE
CONmOL PROGRAM AT (858) SURE IT IS INTACT AND
694-2888. MOSQUITO LARVICIDES UNOBSmUCTED. ABATE ANY
SHOULD BE APPLIED ONLY WHEN POTENTIAL VECTORS BY FILLING
ABSOLUTELY NECESSARY AND THEN HOLES IN THE GROUND IN AND
ONLY BY A LICENSED INDIVIDUAL AROUND THE BIOFILTER FACILITY
CONmACTOR. AND BY INSURING THAT THERE ARE
NO AREAS WHERE WATER STANDS
LONGER THAN 96 HOURS FOLLOWING
A STORM.
OUTLET INLET OR OUTLET CLEAR OBSmUCTIONS.
smucTURE
DAMAGE TO smucTURAL REPAIR OR REPLACE AS APPL/GABL£
COMPONENTS SUCH AS WEIRS, INLET,
OR OUTLET smucTURES
BEFORE THE WET SEASON AND WHERE CISTERNS ARE PART OF THE
AFTER RAIN EVENTS: REMOVE SYSTEM
SEDIMENT AND DEBRIS FROM
SCREENS AND OVERFLOW DRAINS
AND DOWNSPOUTS: ENSURE PUMPS
ARE FUNCTIONING, WHERE
APPLICABLE; CHECK INTEGRITY OF
MOSQUITO SCREENS; AND; CHECK
THAT COVERS ARE PROPERLY
SEALED AND LOCKED.
GENERAL MAINTENANCE NOTES
1. 8/0FIL mA TION BMPS WILL INCLUDE AMENDED SOILS,
SUBSURFACE GRAVEL LA YER, AND AN UNOERDRAIN.
2. GRATED LIDS ON CATCH BASINS CAN BE REMOVED FOR
INSPECTING ALL UNDERGROUND COMPONENTS THAT
REQUIRE INSPECTION ANO MAINTENANCE
3. BIOFIL mA TION BMPS REQUIRE ROUTINE LANDSCAPE
MAINTENANCE USING THE SAME EQUIPMENT THAT JS USED
FOR GENERAL LANDSCAPE MAINTENANCE
4. REFER TO MAINTENANCE IND/CA TORS AND ACTIONS TABLE
FOR MAINTENANCE THRESHOLDS AND ACTIONS.
K:\Civil 3D\1383\GRAND\DWG\SWMP\1383-800 Grand-DMA Exhibit 10-26-16.dwg, 10/26/2016 4:29:40 PM
·-,
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I c-,
'
BMP PLAN SHEET
800 G VA VENUE
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LEGEND SYMBOL
;;,.~~-'-;-:-;~-'!;;....(S_'F_;------------l( 3:i~~s1 SF)
SELF-MIT/GA TING OMA SM 1
DE MIN/MIS OMA DMIN 1
POINT OF CONCENTRA T/ON POC 1
DMA BOUNDARY
PROPERTY LINE
FLOW DIRECTION
PROPOSED CONCRETE SIDEWALK
PROPOSED 8/0FIL mA TTON BASIN
r · ·· · · · · ·· · ····· · ·1 ................... ................... ................... ...................
PROJECT CHARACTERISTICS
PARCEL AREA 0.96 ACRES
DISTURBED AREA 0.96 ACRES
PROPOSED IMPERVIOUS AREA 0.84 ACRES
PROPOSED PERVIOUS AREA 0.12 ACRES
SOIL TYPE B
DEPTH TO GROUNDWATER > 20 FEET
BMP FOOTPRINT
DOWNSPOUT
STRUCTURAL
WALLS W/
WATERPROOF
MEMBRANE
SPLASH PA,..__,.
IMPERMEABLE
UN£R
6"-DIA P£RFORA TED
PVC PIP£
II .J.--=24"x24" BROOKS
CATCH BASIN W/
GRATED INLET
MULCH LAYER
(3" MIN)
L:,;';i;+--18" MIN
""/0. ,,,,. £NGIN££R£D
SOIL MEDIA
~'4---2• PEA GRAV£L
Bi1~§:'.9:~~~~t--10· AGGREGATE "··,: .. ., • STORAGE LA Y£R
SUBGRAD£
BIOFIL TRA TION BASIN
DETAIL, TYPICAL
NOT TD SCALE
3" AGGR£GA TE BELOW
UND£RDRAIN
B:MP FOOTPRINT
BASIN PROPOSED BASIN
AREA
BMP IA 861 SF
BMP 18 861 SF
20· 1 o' o· 20' 40· 50' ~~·
SCALE: 1" = 20'
b~A,lnc.
land planning, cMI englneenng, suiveylng
5115 AVENIDA ENCINAS
SUITE "L"
CARLSBAD, CA. 92008-4387
(760) 931-8700
------· ··-·------.
BMP PLAN SHEET
800 GRAND A VENUE
CARLSBAD, CA
W0.1026-1383-400 SHEET 1
----·------·
OF 1
Attachment 4
Geotechnical Study
49
..
8AGS ADVANCED GEOTECHNICAL SOLUTIONS, INC.
485 Corporate Drive, Suite B
Escondido, California 92029
Telephone: (619) 867-0487 Fax: (714) 409-3287
McKellar McGowan
888 Prospect St. #330
La Jolla CA 92037
Attention: Mr. Chris McKellar
October 21, 2016
P/W 1607-03
Report No. 1607-03-B-2
Subject: Geotechnical Investigation and Foundation Design Recommendations for Proposed
Residential Multi-Family Podium Structure (Grand Ave.) and Single Family (Home
Ave.), 800 Grand Project, Carlsbad, California
Gentlemen,
In accordance with your request, presented herein are the results of Advanced Geotechnical Solutions,
Inc.'s (AGS) geotechnical investigation and foundation design recommendations for the proposed
residential structures to be located at 800 Grand A venue, Carlsbad, California. As we understand the
project the site will be separated into two pieces: the Home Avenue portion (5 unit single family
residential) and the 800 Grand portion (partially subterranean podium structure) .
The recommendations presented in the following report are based on a limited subsurface investigation
performed by AGS and associated laboratory testing. It is AGS's opinion, from a geotechnical standpoint,
the subject site is suitable for construction of the proposed residences, provided the recommendations
presented in this report are incorporated into the design, planning and construction phases of site
development. Included in this report are: 1) engineering characteristics of the onsite soils; 2) unsuitable
soil removal recommendations; 3) grading recommendations; 4) foundation design recommendations; and
5) storm water infiltration feasibility analysis.
Advanced Geotechnical Solutions, Inc., appreciates the opportunity to provide you with geotechnical
consulting services and professional opinions. If you have any questions, please contact the undersigned
at (619) 867-0487.
Respectfully Submitted,
Advanced Geotechnical Solutions, Inc.
Distribution:
Attachments:
(3) Addressee
Figure I -Site Location Map;
Figure 2 -Geologic Map and Exploration Plan;
Plate I -Site Geologic Map; Plate 2 -Cross-Sections;
Appendix A -Field and Laboratory Data;
Appendix B -General Earthwork Specifications & Grading Guidelines;
Appendix C -Homeowner Maintenance Recommendations;
Appendix D -Preliminary Storm Water Infiltration Feasibility Analysis
ORANGE AND L.A. COUNTIES
(714) 786-5661
INLAND EMPIRE
(619) 867-0487
SAN DIEGO AND IMPERIAL COUNTIES
(619) 867-0487
...
GEOTECHNICAL INVESTIGATION AND FOUNDATION DESIGN
RECOMMENDATIONS FOR PROPOSED RESIDENTIAL MULTI-FAMILY
PODIUM STRUCTURE (Grand Ave.) and SINGLE FAMILY (Home Ave.)
800 GRAND PROJECT
CARLSBAD,CALIFORNIA
""
..
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..
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...
..
October 21, 2016
P/W 1607-03
Page 1
Report No. 1607-03-B-2
1.0 SCOPE OF SERVICES
This study is aimed at providing geotechnical information as it relates to: 1) existing site soil conditions; 2)
discussion of the geologic units onsite; 3) seismic hazard analysis; 4) engineering characteristics of the onsite
soils; 5) excavation characteristics of earth materials; 6) seismic design parameters for use in the structural
design of the proposed single-family residences; 7) foundation design parameters for the proposed
conventional shallow foundation systems; and 8) storm water infiltration onsite.
The scope of our study included the following tasks:
2.0
);., Review of pertinent published and unpublished geologic and geotechnical literature, maps, and aerial
photographs.
);., Excavate, log, and sample: two (2) exploratory borings (TB-1 and TB-2) with a limited access tripod
drill rig and four Hollowstem Auger Borings (HS-1 thru HS-4) excavated with a truck mounted drill
rig CME 55 (Appendix A).
);., Laboratory testing of representative bulk and "undisturbed" ring samples including moisture content
and density, maximum density and optimum moisture content, shear strength, and chemical/resistivity
analysis. (Appendix A)
);., Excavate three (3) percolation test borings with tripod rig or with a truck mounted Hollowstem Auger
to conduct infiltration testing in accordance with Appendix D of the final Model BMP Design Manual
for the San Diego Region, adopted by the City of Carlsbad.
);., Conduct a geotechnical engineering and geologic hazard analysis of the site.
);., Conduct a limited seismicity analysis.
);., Determine the site-specific seismic design parameters for use in the structural design .
);., Determine design parameters of onsite soils as a foundation medium including bearing and friction
values for foundation soils.
);., Preparation of a geotechnical foundation investigation report with exhibits summarizing our findings .
This report would be suitable for design, contractor bidding, and regulatory review.
GEOTECHNICAL STUDY LIMITATIONS
The conclusions and recommendations in this report are professional opinions based on our field investigation,
associated lab testing, review of referenced geotechnical maps, and our experience in the area.
The materials immediately adjacent to or beneath those observed may have different characteristics than those
observed. No representations are made as to the quality or extent of materials not observed. Any evaluation
regarding the presence or absence of hazardous material is beyond the scope of this firm's services.
3.0 SITE LOCATION AND DESCRIPTION
The "L" shaped 1.38 acre site is located at 800 Grand Avenue, Carlsbad, California (Figure 1, Site Location
Map). The site is bounded by Grand A venue to the south, commercial and apartment building to the east and
west and to the north by an apartment building and Home Avenue. The larger southerly portion (Parcel A-
called the Grand A venue portion) is occupied by three older slab-on-grade, two story wood framed office
ADVANCED GEOTECHNICAL SOLUTIONS, INC .
..
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SITE LOCATION MAP
800 GRAND AVE
CARLSBAD, CALIFORNIA
SOURCE MAP(S): TOPOGRAPHIC MAP OF THE
SAN LUIS REY 7.5 MINUTE QUADRANGLE
SAN DIEGO COUNTY, CALIFRONIA
FIGURE 1
~m~~c s ADVANCED GEOTECHNICAL SOLUTIONS. INC. .. 485 Corporate Drive, Suite B, Escondido Ca, 920925
Telephone: (619) 726-1046 Fax: (714) 409-3287
PIW 1607-03 Report No. 1607-03-8-2
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I SITE LOCATION MAP
800 GRAND AVE
CARLSBAD, CALIFORNIA
SOURCE MAP(S): TOPOGRAPHIC MAP OF THE
SAN LUIS REY 7.5 MINUTE QUADRANGLE
SAN DIEGO COUNTY, CALIFRONIA
FIGURE 1 e. ~ ~AG s ADVANCED GEOTECHNICAL SOLUTIONS, INC. · ~ 485 Corporate Drive, Suite B, Escondido Ca, 920925
Telephone: (619) 726-1046 Fax: (714) 409-3287
P/W 1607-03 Report No. 1607-03-8-2
..
...
...
October 21, 2016
P/W 1607-03
Page 3
Report No. 1607-03-B-2
6.0 ENGINEERING GEOLOGY
6.1. Geologic and Geomorphic Setting
The subject site is situated within the Peninsular Ranges Geomorphic Province. The Peninsular Ranges
province occupies the southwestern portion of California and extends southward to the southern tip of
Baja California. In general the province consists of young, steeply sloped, northwest trending
mountain ranges underlain by metamorphosed Late Jurassic to Early Cretaceous-aged extrusive
volcanic rock and Cretaceous-aged igneous plutonic rock of the Peninsular Ranges Batholith. The
westernmost portion of the province is predominantly underlain by younger marine and non-marine
sedimentary rocks. The Peninsular Ranges' dominant structural feature is northwest-southeast trending
crustal blocks bounded by active faults of the San Andreas transform system.
6.2. Subsurface Conditions
A brief description of the earth materials encountered on this site is presented in the following
sections. More detailed descriptions of these materials are provided in the boring logs included in
Appendix A. Based on our site reconnaissance, subsurface excavations, and review of the referenced
geologic map, the site is underlain to the depths explored by old paralic deposits (marine terrace
deposits) which are locally overlain by a relatively thin veneer of undocumented fill soils. A site
geologic map is presented in Figure 2 .
Artificial Fill-Undocumented (afu)
Undocumented fill soils were encountered in the onsite excavations and observed to overlie the old
paralic deposits. As encountered in our limited subsurface investigation, the undocumented fill soils
were approximately one foot thick, it is anticipated that thicker sequences ( 4 to 6 feet) may be present
onsite within the existing utility lines. As encountered, these materials generally consisted of brown,
dry to slightly most, fine-grained sand with some silt in a loose condition .
Old Paralic Deposits (Map symbol Qop6)
The site is underlain to maximum depth explored by old paralic deposits. These materials can
generally be described as orange brown to light brownish gray, slightly moist to moist, medium dense
to dense, fine-grained sand. At the contact between the old paralic deposits and the underlying
Santiago formation was a coarse grained sandy to gravelly lag deposit which was found to be
approximately six to twelve inches thick and saturated.
Santiago Formation (Tsa)
The bedrock unit underlying the site is assigned to the Eocene-aged Santiago Formation. The unit is
composed predominately of a relatively massive grey green sandy silt stone that is fine-to coarse-
grained to a silty claystone. Subunits of sandy siltstone and silty claystone are common throughout.
6.3. Groundwater/Saturated Soils
Groundwater/saturated soils were encountered in exploratory soil borings on site. Groundwater was
found to vary from 14fbg (southeast comer of the site) adjacent to Grand Street to 16.5 fbg feet from
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
SITE 0
N
SITE GEOLOGIC MAP
800 GRAND AVE. 1 CARLSBAD, CALIFORNIA
SOURCE MAP(S): GEOLOGIC MAP OF THE
OCEANSIDE, 30x60 QUADRANGLE
CALIFORNIA, KENNEDY AND TAN, 2005
FIGURE2 e. ~ ~iAG s ADVANCED GEOTECHNICAL SOLUTIONS, INC. ~ 485 Corporate drive, Suite B, Escondido Ca, 92025
Telephone: (619) 726-1046 Fax: (714) 409-3287
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existing grade in the northwest portion of the site adjacent to Home Avenue. It is our opinion that the
groundwater is collecting in the coarser lag deposits on top of the Santiago formation and is generally
draining in a northwesterly direction towards Buena Vista Lagoon. It should be noted that the
groundwater level may vary, due to fluctuations in precipitation, irrigation practices, infiltration water
from adjacent properties, or factors not evident at the time of our field explorations.
6.4. Non-seismic Geologic Hazards
Mass Wasting
Given the flat nature of the site no evidence of mass wasting was observed onsite nor was any noted on
the reviewed maps.
Flooding
According to available FEMA maps, the site is not in a FEMA identified flood hazard area.
Subsidence/Ground Fissuring
Due to the presence of the relatively dense underlying materials and the removals proposed herein, the
potential for subsidence and ground fissuring due to settlement is unlikely.
6.5. Seismic Hazards
The site is located m the tectonically active Southern California area, and will therefore likely
experience shaking effects from earthquakes. The type and severity of seismic hazards affecting the
site are to a large degree dependent upon the distance to the causative fault, the intensity of the seismic
event, and the underlying soil characteristics. The seismic hazard may be primary, such as surface
rupture and/or ground shaking, or secondary, such as liquefaction or dynamic settlement. The
following is a site-specific discussion of ground motion parameters, earthquake-induced landslide
hazards, settlement, and liquefaction. The purpose of this analysis is to identify potential seismic
hazards and propose mitigations, if necessary, to reduce the hazard to an acceptable level of risk. The
following seismic hazards discussion is guided by the California Building Code (2013), CDMG
(2008), and Martin and Lew ( 1998).
~ Surface Fault Rupture
No known active faults have been mapped at or near the subject site. The nearest known active
surface fault is the Oceanside section of the Newport-Inglewood-Rose Canyon fault zone which is
approximately 4. 7 miles west of the subject site. Accordingly, the potential for fault surface rupture on
the subject site is considered to be low to remote. This conclusion is based on literature review and
aerial photograph analysis.
)i-Seismicity
As noted, the site is within the tectonically active southern California area, and is approximately 4.7
miles from an active fault, the Oceanside section of the Newport-Inglewood-Rose Canyon fault zone.
The potential exists for strong ground motion that may affect future improvements.
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7.0
At this point in time, non-critical structures (commercial, residential, and industrial) are usually
designed according to the California Building Code (2013) and that of the controlling local agency.
However, liquefaction/seismic slope stability analyses, critical structures, water tanks and unusual
structural designs will likely require site specific ground motion input.
~ Liquefaction
In consideration of the proposed remedial grading recommendations presented herein and the
relatively dense nature and age (middle to late Pleistocene) of the deeper underlying old paralic
deposits at the project site, the potential for seismically induced liquefaction is considered low.
~ Dynamic Settlement
Dynamic settlement occurs in response to an earthquake event in loose sandy earth materials. This
potential of dynamic settlement at the subject site is considered low due to the presence of the old
paralic deposits and the proposed removals of loose, sandy soils.
~ Seismically Induced Landsliding
The topography on site is flat. As such, the potential for landsliding on site is considered nil.
~ Tsunamis
Our review of the 2009 Tsunami Inundation Map for Emergency Planning, Point Loma Quadrangle,
prepared by CalEMA, indicates the project site is not located within the tsunami inundation line. This
line represents the maximum considered tsunami run-up from a number of local and distant tsunami
sources. The suite of tsunami source events selected for modeling represent possible but extreme and
rare events. As such, no information about the probability of any tsunami affecting any area within a
specific period of time is provided. In addition, the map does not represent inundation from a single
scenario event. Rather, it was created by combining inundation results for an ensemble of source
events affecting a region.
Recent studies indicate that significant run-up heights in the Carlsbad area due to distant tsunami
source events are highly unlikely in consideration of the offshore topography and presence of islands
along the southern California borderlands. In addition, the protected shoreline in the project vicinity
will further inhibit significant run-up heights during a tsunami event. Accordingly, it is our opinion
that tsunamis are not a significant risk at the project site.
GEOTECHNICAL ENGINEERING
Presented herein is a general discussion of the geotechnical properties of the various soil types and the analytic
methods used in this report.
7.1. Material Properties
7 .1.1 Excavation Characteristics
Based on our previous experience with similar projects near the subject site and the
information gathered in preparing this report, it is our opinion that the undocumented fill soils
and Old Paralic Deposits are readily excavatable with conventional grading equipment.
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However, it should be anticipated that well cemented zones could be encountered within the
old paralic deposits that may be difficult to excavate. Specialized grading equipment (large
excavators and/or bull dozers) may be necessary to efficiently excavate portions of the old
paralic deposits.
7.1.2 Compressibility
The near surface undocumented fill soils and the weathered one to two feet of the Old Paralic
deposits are considered to be moderately compressible in their present condition.
Compressibility of the unweathered old paralic deposits is not a geotechnical design concern
for the proposed structures.
7.1.3 Collapse Potential/Hydro-Consolidation
Given the relatively thin veneer of undocumented fill soils on top of the generally dense
formational materials, and the removals proposed herein, the potential for hydro-consolidation
is considered remote at the subject site.
7.1.4 Expansion Potential
Based on our previous experience in the area with similar materials, the onsite soils exposed
within the upper 10 to 15 feet will likely exhibit a "very low to low" expansion potential.
7.1.5 Shear Strength
Based upon our laboratory testing and our previous experience in the area with similar soils,
the following are proposed shear strengths for compacted fill and old paralic deposits.
TABLE 7.1.5
SHEAR STRENGTHS
Material Cohesion Friction Angle
(psf) (degrees)
Compacted Fill 150 34
Old Paralic Deposits 250 35
7.1.6 Chemical/Resistivity Test Results
Preliminary soluble sulfate and chloride, and res1shv1ty testing was conducted on a
representative bulk sample obtained during subsurface exploration (Appendix A). Based upon
the test results and our previous experience in the area it is anticipated that the onsite soil will
exhibit "negligible" sulfate concentrations when classified in accordance with ACI 318-05
Table 4.3. I (per 2013 CBC).
Testing reveals that soil on site has a "low" corrosion potential to metal construction materials
in direct contact to the onsite soils.
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8.0
7.1.8 Earthwork Adjustments
It is anticipated that the onsite fill soils and weathered old paralic deposits will shrink on the
order of 5 to 10 percent when re-compacted. The fresher, old paralic deposits are anticipated to
bulk on the order of 4 to 8 percent when used to make compacted fill.
7.1.9 Pavement Support Characteristics
It is anticipated that the onsite soils will have good to moderate support characteristics.
Depending upon the final distribution of site soils, pavement support characteristics could
vary. If structural pavements are to be constructed (concrete or asphaltic concrete), an "R"-
value of 35 can be utilized for the preliminary design of pavements. Final design should be
based upon representative sampling of the as-graded soils.
7.1.10 Infiltration Potential
AGS conducted three borehole percolation tests (P-1 and P-2) in the southern portion of the
site (Grand Avenue) and one test (HSP-3) in the northern portion of the site (Home Avenue),
in accordance with the testing methods described in Appendix D of the BMP Design Manual.
Based on the results of our subsurface investigation, it is anticipated that the dense upper
portions of the sandy Old Paralic deposits onsite possess relatively high to moderate
infiltration rates. Infiltration rates were calculated using the Porchet method. Measured
infiltration rates varied from between 0.77 in/hr and 2.83 in/hr.
CONCLUSIONS AND RECOMMENDATIONS
Construction of the proposed "Podium" structure (Grand Avenue) and the single family residential structures
(Home Avenue) and associated improvements are considered feasible, from a geotechnical standpoint,
provided that the conclusions and recommendations presented herein are incorporated into the design and
construction of the project. Presented below are specific issues identified by this study as possibly affecting
site development. Recommendations to mitigate these issues are presented in the text of this report.
8.1. Grading Recommendations
8.1.1 Unsuitable Soil Removals
In areas to receive settlement sensitive structures, all undocumented fill soils and highly
weathered formational materials should be removed. It is anticipated that the upper 1 to 3 feet
of the onsite soils will require removal and recompaction for the support of settlement
sensitive structures. Localized areas may require deeper removals. Minimally the removals
should extend a lateral distance of at least 5 feet beyond the limits of settlement sensitive
structures. If deeper removals are performed, the removals should extend a lateral distance
equal to the depth of removal beyond the improvement limits. Removal bottoms should
expose competent formational materials in a firm and unyielding condition. The resulting
removal bottoms should be observed by a representative of AGS to verify that adequate
removal of unsuitable materials have been conducted prior to fill placement. In general, soils
removed during remedial grading will be suitable for reuse in compacted fills, provided they
are properly moisture conditioned and do not contain deleterious materials. Grading shall be
accomplished under the observation and testing of the project soils engineer and engineering
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geologist or their authorized representative in accordance with the recommendations
contained herein, the current grading ordinance of the City of Carslsbad.
8.2. Earthwork Considerations
8.2.1 Compaction Standards
Fill and processed natural ground shall be compacted to a minimum relative compaction of 90
percent, as determined by ASTM Test Method: D 1557. Compaction shall be achieved at or
slightly above the optimum moisture content and as generally discussed in the attached
Earthwork Specifications (Appendix B).
8.2.2 Compaction Standards
At the completion of unsuitable soil removals, the exposed bottom should be scarified to a
minimum depth of eight inches, moisture conditioned to above optimum moisture and
compacted in-place to the standards set forth in this report.
8.2.3 Compaction Standards
Fill should be placed in thin lifts (eight-inch bulk), moisture conditioned to at or slightly above
the optimum moisture content, uniformly mixed, and compacted by the use of both wheel
rolling and kneading type (sheep's foot) compaction equipment until the designed grades are
achieved.
8.3. Design Recommendations
The following design recommendations have been separated due to the different building types. Grand
A venue will consist of a "Podium" structure with a partially subterranean structure and Home A venue
with will be conventional slab-on-grade wood frame structures.
8.3.1 Grand A venue-Podium Structure
It is our understanding that the proposed Grand A venue condominium building will consist of
a "Podium" with a partially subterranean "Mat" slab-on-grade foundation system. The podium
will support the three-story wood-frame residential structure. It is anticipated that the
foundation systems will likely be a "Mat" system with CMU basement walls. In addition to
the structures, associated driveways, hardscape and landscape areas are proposed. From a
geotechnical perspective these proposed improvements are feasible provided that the following
recommendations are incorporated into the design and construction.
8.3.1.1. Foundation Design Criteria Podium Structure -Grand Avenue
The residential condominium podium structure can be supported on a shallow "mat"
foundation system. For preliminary design, the expansion potential of the underlying
soils can be considered "Very Low" to "Low". The following values may be used in
the foundation design.
Allowable Bearing: 3000 lbs./sq.ft.
Lateral Bearing: 350 lbs./sq.ft. at a depth of 12 inches plus
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200 lbs./sq.ft. for each additional 12 inches
embedment to a maximum of 5000 lbs./sq.ft.
Sliding Coefficient:
Settlement:
Differential:
0.37
Total= 3/4 inch
3/8 inch in 20 feet
The above values may be increased as allowed by Code to resist transient loads such
as wind or seismic. Building Code and structural design considerations may govern.
Depth and reinforcement requirements should be evaluated by the Structural Engineer.
Based upon the onsite soil conditions and information supplied by the 2013 CBC,
conventional foundation systems should be designed in accordance with Section
8.2. l. l and the following recommendations.
~ Continuous Footings-
Depth-Minimum of 24 inches
Width-Minimum of 18 inches
Reinforcement-Minimum four No.5 rebar's, two top and two bottom
Isolated Spread Footings-Minimum of 24 inches wide and 24 inches deep
(Reinforcement per structural engineer)
Garage Slab-Minimum of 5 inches thick with # 3 rebar on 15 inch centers
both ways. Consideration should be given to underlay the garage slab with a
moisture barrier.
Garage Slab Entrance-A grade beam reinforced continuously with the
garage footings shall be constructed across the garage entrances, tying
together the ends of the perimeter footings and between individual spread
footings. This grade beam should be embedded a minimum of 18 inches. A
thickened slab, separated by a cold joint from the garage beam, should be
provided at the garage entrance. Minimum dimensions of the thickened edge
shall be six (6) inches deep. Footing depth, width and reinforcement should
be the same as the structure. Slab thickness, reinforcement and under-slab
treatment should be the same as the structure.
8.3.2 Home A venue-Conventional Slab-On-Grade
The conventional slab-on-grade residential one to two story structures can be supported on
conventional shallow foundation and slab-on-grade systems. For preliminary design, the
expansion potential of the underlying soils can be considered "Very Low" to "Low". The
following values may be used in the foundation design.
Allowable Bearing:
Lateral Bearing:
2000 lbs./sq.ft.
300 lbs./sq.ft. at a depth of 12 inches plus
200 lbs./sq.ft. for each additional 12 inches
embedment to a maximum of 2000 lbs./sq.ft.
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Sliding Coefficient: 0.40
Settlement:
Differential:
Total= 3/4 inch
3/8 inch in 20 feet
The above values may be increased as allowed by Code to resist transient loads such as wind
or seismic. Building Code and structural design considerations may govern. Depth and
reinforcement requirements should be evaluated by the Structural Engineer. Based upon the
onsite soil conditions and information supplied by the 2013 CBC, conventional foundation
systems should be designed in accordance with Section 8.2.1 and the following
recommendations.
Interior and exterior footings for one-story structures should be a minimum of
12 inches wide and extend to a depth of at least 12 inches below lowest
adjacent grade. Footing reinforcement should minimally consist of four No. 4
reinforcing bars, two top and two bottom or two No. 5 reinforcing bars, one
top and one bottom.
Interior and exterior footings for two-story structures should be a minimum of
15 inches wide and extend to a depth of at least 18 inches below lowest
adjacent grade. Footing reinforcement should minimally consist of four No. 4
reinforcing bars, two top and two bottom or two No. 5 reinforcing bars, one
top and one bottom.
Interior and exterior footings for three-story structures should be a minimum
of 18 inches wide and extend to a depth of at least 24 inches below lowest
adjacent grade. Footing reinforcement should minimally consist of four No. 4
reinforcing bars, two top and two bottom or two No. 5 reinforcing bars, one
top and one bottom.
Conventional, slab-on-grade floors, underlain by "low" expansive soil, should
be five or more inches thick and be reinforced with No. 3 or larger reinforcing
bars spaced 18 inches on center each way. The slab reinforcement and
expansion joint spacing should be designed by the Structural Engineer.
If exterior footings adjacent to drainage swales are to exist within five feet
horizontally of the swale, the footing should be embedded sufficiently to
assure embedment below the swale bottom is maintained. Footings adjacent
to slopes should be embedded such that a least seven feet are provided
horizontally from edge of the footing to the face of the slope.
Isolated spread footings outside the footprint of the proposed structures should
be tied with grade beams to the structure in two orthogonal directions.
A grade beam reinforced continuously with the garage footings shall be
constructed across the garage entrance, tying together the ends of the
perimeter footings and between individual spread footings. This grade beam
should be embedded at the same depth as the adjacent perimeter footings. A
thickened slab, separated by a cold joint from the garage beam, should be
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8.4
provided at the garage entrance. Minimum dimensions of the thickened edge
shall be six (6) inches deep. Footing depth, width and reinforcement should
be the same as the structure. Slab thickness, reinforcement and under-slab
treatment should be the same as the structure.
Seismic Design Parameters
The following seismic design parameters are presented to be code compliant to the California Building
Code (2013). The subject parcels have been identified to be Site Class "C" in accordance with CBC,
2013, Section 1613.3.2 and ASCE 7, Chapter 20. The lots are located at Latitude 33.1633°N, and
Longitude 117.3462° W. Utilizing this information, the United States Geological Survey (USGS) web
tool (http://earthquake.usgs.gov/hazards/designmaps/) and ASCE 7 criterion, the mapped seismic
acceleration parameters Ss, for 0.2 seconds and S1, for 1.0 second period (CBC, 2013, 1613.3.1) for
Risk-Targeted Maximum Considered Earthquake (MCER) can be determined. The mapped
acceleration parameters are provided for Site Class "B". Adjustments for other Site Classes are made,
as needed, by utilizing Site Coefficients Fa and Fv for determination of MCER spectral response
acceleration parameters SMs for short periods and SM 1 for 1.0 second period (CBC, 2013 1613.3.3) .
Five-percent damped design spectral response acceleration parameters Sos for short periods and S01 for
1.0 second period can be determined from the equations in CBC, 2013, Section 1613.3.4.
TABLES.4
SEISMIC DESIGN CRITERIA
Mapped Spectral Acceleration (0.2 sec Period), Ss 1.147g
Mapped Spectral Acceleration ( 1.0 sec Period), S 1 0.440g
Site Coefficient, Fa 1.000
Site Coefficient, Fv 1.360
MCE Spectral Response Acceleration (0.2 sec Period), SMs 1.147g
MCE Spectral Response Acceleration (1.0 sec Period), SM1 0.598g
Design Spectral Response Acceleration (0.2 sec Period), SDs 0.764g
Design Spectral Response Acceleration ( 1.0 sec Period), SD1 0.399g
Utilizing a probabilistic approach, the CBC recommends that structural design be based on the peak
horizontal ground acceleration (PGA) having of 2 percent probability of exceedance in 50 years
(approximate return period of 2,475 years) which is defined as the Maximum Considered Earthquake
(MCE). Using the United States Geological Survey (USGS) web-based ground motion calculator, the
site class modified PGAM CFrGA *PGA) was determined to be 0.454g. This value does not include near-
source factors that may be applicable to the design of structures on site.
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8.5
8.6
8.7
Deepened Footings and Structural Setbacks
It is generally recognized that improvements constructed in proximity to natural slopes or properly
constructed, manufactured slopes can, over a period of time, be affected by natural processes including
gravity forces, weathering of surficial soils and long-term (secondary) settlement. Most building
codes, including the California Building Code (CBC), require that structures be set back or footings
deepened, where subject to the influence of these natural processes.
Grading plans for the subject site were not available for review at the time of this report, but as AGS
understands the project, no slopes greater than 5 feet are planned. If foundations for residential
structures are to exist in proximity to slopes, the footings should be embedded to satisfy the
requirements presented in Figure 4 .
Under Slab
FACE OF
STRUCTURE
TOE OF SLOPE
H/2 BUT NEED NOT
EXCEED 15 FT. MAX.
FIGURE4
FACE OF
FOOTING
TOP OF
SLOPE
H/3 BUT NEED NOT EXCEED 40 FT.
MAX. H
j
Prior to concrete placement the subgrade soils should be moisture conditioned to optimum moisture
content.
A moisture and vapor retarding system should be placed below the slabs-on-grade in portions of the
structure considered to be moisture sensitive. The retarder should be of suitable composition,
thickness, strength and low permeance to effectively prevent the migration of water and reduce the
transmission of water vapor to acceptable levels. Historically, a 10-mil plastic membrane, such as
Visqueen, placed between one to four inches of clean sand, has been used for this purpose. More
recently Stego® Wrap or similar underlayments have been used to lower permeance to effectively
prevent the migration of water and reduce the transmission of water vapor to acceptable levels. The
use of this system or other systems, materials or techniques can be considered, at the discretion of the
designer, provided the system reduces the vapor transmission rates to acceptable levels.
Concrete Design
Laboratory testing and our previous experience in the general area indicates onsite soils likely exhibit a
"negligible" sulfate exposure when classified in accordance with ACI 318-11 Table 4.2. l. Final
determination will be based upon testing of near surface soils obtained at the conclusion of grading.
However, some fertilizers have been known to leach sulfates into soils otherwise containing
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8.8
8.9
"negligible" sulfate concentrations and increase the sulfate concentrations to potentially detrimental
levels. It is incumbent upon the owner to determine whether additional protective measures are
warranted to mitigate the potential for increased sulfate concentrations to onsite soils as a result of the
future homeowner' s actions.
Corrosion
Resistivity tests performed indicate that the onsite soils possess a "low" corrosion potential to buried
metallic materials. It is our understanding that only the last ten feet of the domestic and fire waterlines
will be metallic, with the remainder of these lines being non metallic. Further, the proposed plumbing
for each structure will not be located under slab but will be located in the walls and roofs. Provided
that all metallic piping is wrapped with a suitable corrosion inhibiting material (foam, plastic sleeve,
tape, or similar products) and that non-aggressive backfill (sand) soils are placed around all metallic
pipe, no other requirements are deemed necessary to address the "moderately" corrosive soils found
onsite .
Retaining Walls
At the time of this report, grading plans were not available for our review. As AGS understands the
project, no buried structures or retaining walls are anticipated. The following earth pressures are
recommended for design if retaining walls are proposed onsite. At rest earth pressures should be used
in the design of restrained basement walls.
Static Case
Compacted Fill/Old Paralic Deposits (34° at 125pcf):
Rankine
Level Backfill Coefficients
Coefficient of Active Pressure: Ka= 0.28
Coefficient of Passive Pressure: Kr = 3.54
Coefficient of At Rest Pressure: K0 = 0.44
Seismic Case
Equivalent Fluid
Pressure (psf/lin.ft.)
35
442
55
In addition to the above static pressures, unrestrained retaining walls should be designed to resist
seismic loading. In order to be considered unrestrained, retaining walls should be allowed to rotate a
minimum of roughly 0.004 times the wall height. The seismic load can be modeled as a thrust load
applied at a point 0.6H above the base of the wall, where H is equal to the height of the wall. This
seismic load (in pounds per lineal foot of wall) is represented by the following equation:
Pe = % *y*H2 *kh
Where:
H = Height of the wall (feet)
y = soil density = 125 pounds per cubic foot (pcf)
kh = Y2 * peak horizontal ground acceleration= Y2 * 0.537g
Walls should be designed to resist the combined effects of static pressures and the above seismic
thrust load .
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A bearing value of 3,000 psf may be used for design of basement walls. A value of 0.40 may be used
to model the frictional between the soil and concrete. For sliding passive pressure both passive and
friction can be combined to a maximum of 2/3 the total.
Retaining wall footings should be designed to resist the lateral forces by passive soil resistance and/or
base friction as recommended for foundation lateral resistance. To relieve the potential for hydrostatic
pressure wall backfill should consist of a free draining backfill (sand equivalent "SE" >20) and a heel
drain should be constructed. The heel drain should be place at the heel of the wall and should consist
of a 4-inch diameter perforated pipe (SDR35 or SCHD 40) surrounded by 4 cubic feet of crushed rock
(3/4-inch) per lineal foot, wrapped in filter fabric (Mirafi® 140N or equivalent).
Proper drainage devices should be installed along the top of the wall backfill, which should be
properly sloped to prevent surface water ponding adjacent to the wall. In addition to the wall drainage
system, for building perimeter walls extending below the finished grade, the wall should be
waterproofed and/or damp-proofed to effectively seal the wall from moisture infiltration through the
wall section to the interior wall face. Retaining wall backfill and drains should be constructed in
general conformance to RTW-A. Final design of the waterproofing should be determined by the
Architect.
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WATERPROOFING PROVIDE
MEMBRANE DRAINAGE
SWALE
/r
12 in.
min. ______________ 1 ____ :
SELECT i
BACKFILL i
H (E1~20 & \
SE~20) j
,f
NATIVE
BACKFILL
(El~50)
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. ~Hl2_J.
I min. f 1:1 (H:V) OR FLATTER
VER 1.0
. i \
i \
. i ! . i i
t[QTES (1) DRAIN: 4-INCH PERFORATED ABS OR PVC PIPE OR APPROVED EQUIVALENT
SUBSTITUTE PLACED PERFORATIONS DOWN AND SURROUNDED BY A
MINIMUM OF 1 CUBIC FEET OF 3/4 INCH ROCK OR APPROVED EQUIV ALEN T
SUBSTITUTE AND WRAPPED IN MIRAFI 140 FILTER FABRIC OR APPROVED
EQUIVALENT SUBSTITUTE
RETAINING WALL
ALT. A-SELECT BACKFILL
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8.10
8.11
The retaining walls should be backfilled with granular soils placed in loose lifts no greater
than 8-inches thick, at or near optimum moisture content, and mechanically compacted to a
minimum 90 percent relative compaction as determined by ASTM Test Method D1557.
Flooding or jetting of backfill materials generally do not result in the required degree and
uniformity of compaction and, therefore, is not recommended. The soils engineer or his
representative should observe the retaining wall footings, backdrain installation and be present
during placement of the wall backfill to confirm that the walls are properly backfilled and
compacted.
Utility Trench Excavation
All utility trenches should be shored or laid back in accordance with applicable CAL/OSHA standards.
Excavations in bedrock areas should be made in consideration of underlying geologic structure. AGS
should be consulted on these issues during construction.
Utility Trench Backfill
Mainline and lateral utility trench backfill should be compacted to at least 90 percent of maximum dry
density as determined by ASTM D 1557. Onsite soils will not be suitable for use as bedding material
but will be suitable for use in backfill, provided oversized materials are removed. No surcharge loads
should be imposed above excavations. This includes spoil piles, lumber, concrete trucks or other
construction materials and equipment. Drainage above excavations should be directed away from the
banks. Care should be taken to avoid saturation of the soils.
Compaction should be accomplished by mechanical means. Jetting of native soils will not be
acceptable.
8.12 Exterior Slabs and Walkways
~ Subgrade Compaction
The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be compacted to
a minimum of 90 percent relative compaction as determined by ASTM D 1557.
Subgrade Moisture
The subgrade below exterior slabs, sidewalks, driveways, patios, etc. should be moisture
conditioned to a minimum of 110 percent of optimum moisture content prior to concrete
placement.
Slab Thickness
Concrete flatwork and driveways should be designed utilizing four-inch minimum thickness.
Control Joints
Weakened plane joints should be installed on walkways at intervals of approximately eight to
ten feet. Exterior slabs should be designed to withstand shrinkage of the concrete.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
,,
October 21, 2016
P/W 1607-03
Page 17
Report No. 1607-03-B-2
9.0
10.0
11.0
Flatwork Reinforcement
Consideration should be given to reinforcing any exterior flatwork.
Thickened Edge
Consideration should be given to construct a thickened edge (scoop footing) at the perimeter
of slabs and walkways adjacent to landscape areas to minimize moisture variation below
these improvements. The thickened edge (scoop footing) should extend approximately eight
inches below concrete slabs and should be a minimum of six inches wide.
BMPDESIGN
AGS conducted site specific percolation testing to determine preliminary infiltration rates and evaluate
feasibility for storm water infiltration at the project site. Testing was completed in general accordance
with the new 2016 San Diego Region BMP Design Manual. Worksheet C-4.1 and supporting
documents are presented in Appendix D.
Based on the results of our preliminary testing, Full to Partial Infiltration design for BMPs is
potentially feasible for the Home Avenue portion of the site. For the Grand Avenue portion of the site
AGS does not recommend full or partial infiltration as this portion of the development will be
supported by a partially subterranean garage "Podium" structure. From a geotechnical perspective the
addition of shallow groundwater from infiltration near the podium structure is highly unpredictable. In
some instances infiltration below and adjacent to these types of structures has resulted in: additional
hydraulic forces on basement walls; increase the likelihood for unwanted seepage into the basement;
caused differential settlement across the basement floor; and created mounding of infiltration water
due to the disruption of the horizontal conductivity of the flat lying deposits found in the Old Paralic
deposits.
PLAN REVIEW
Once grading and foundation design plans become available, they should be reviewed by AGS to
verify that the design recommendations presented are consistent with the proposed construction.
GEOTECHNICAL REVIEW
As is the case in any grading project, multiple working hypotheses are established utilizing the
available data, and the most probable model is used for the analysis. Information collected during the
grading and construction operations is intended to evaluate these hypotheses, and some of the
assumptions summarized herein may need to be changed as more information becomes available.
Some modification of the grading and construction recommendations may become necessary, should
the conditions encountered in the field differ significantly than those hypothesized to exist.
AGS should review the pertinent plans and sections of the project specifications, to evaluate
conformance with the intent of the recommendations contained in this report.
If the project description or final design varies from that described in this report, AGS must be
consulted regarding the applicability of, and the necessity for, any revisions to the recommendations
presented herein. AGS accepts no liability for any use of its recommendations if the project
description or final design varies and AGS is not consulted regarding the changes.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
"'"
October 21, 2016
P/W 1607-03
Page 18
Report No. 1607-03-B-2
12.0 SLOPE AND LOT MAINTENANCE
Maintenance of improvements is essential to the long-term performance of structures and slopes. Although the
design and construction during mass grading is planned to create slopes that are both grossly and surficially
stable, certain factors are beyond the control of the soil engineer and geologist. The homeowners must
implement certain maintenance procedures.
The following recommendations should be implemented.
12.1. Lot Drainage
Roof, pad and lot drainage should be collected and directed away from structures and slopes and
toward approved disposal areas. Design fine-grade elevations should be maintained through the life of
the structure or if design fine grade elevations are altered, adequate area drains should be installed in
order to provide rapid discharge of water, away from structures and slopes. Residents should be made
aware that they are responsible for maintenance and cleaning of all drainage terraces, down drains and
other devices that have been installed to promote structure and slope stability.
12.2. Irrigation
The resident, homeowner and Homeowner Association should be advised of their responsibility to
maintain irrigation systems. Leaks should be repaired immediately. Sprinklers should be adjusted to
provide maximum uniform coverage with a minimum of water usage and overlap.
Overwatering with consequent wasteful run-off and ground saturation should be avoided. If automatic
sprinkler systems are installed, their use must be adjusted to account for natural rainfall conditions.
12.3. Burrowing Animals
13.0
Residents or homeowners should undertake a program for the elimination of burrowing animals. This
should be an ongoing program in order to maintain slope stability.
LIMITATIONS
This report is based on the project as described and the information obtained from the excavations at the
approximate locations indicated on Plate 1. The findings are based on the results of the field, laboratory, and
office investigations combined with an interpolation and extrapolation of conditions between and beyond the
excavation locations. The results reflect an interpretation of the direct evidence obtained. Services performed
by AGS have been conducted in a manner consistent with that level of care and skill ordinarily exercised by
members of the profession currently practicing in the same locality under similar conditions. No other
representation, either expressed or implied, and no warranty or guarantee is included or intended.
The recommendations presented in this report are based on the assumption that an appropriate level of field
review will be provided by geotechnical engineers and engineering geologists who are familiar with the design
and site geologic conditions. That field review shall be sufficient to confirm that geotechnical and geologic
conditions exposed during grading are consistent with the geologic representations and corresponding
recommendations presented in this report. AGS should be notified of any pertinent changes in the project
plans or if subsurface conditions are found to vary from those described herein. Such changes or variations
may require a re-evaluation of the recommendations contained in this report.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
..•
..
October 21, 2016
P/W 1607-03
Page 19
Report No. 1607-03-B-2
The data, opinions, and recommendations of this report are applicable to the specific design of this project as
discussed in this report. They have no applicability to any other project or to any other location, and any and
all subsequent users accept any and all liability resulting from any use or reuse of the data, opinions, and
recommendations without the prior written consent of AGS.
AGS has no responsibility for construction means, methods, techniques, sequences, or procedures, or for safety
precautions or programs in connection with the construction, for the acts or omissions of the CONTRACTOR,
or any other person performing any of the construction, or for the failure of any of them to carry out the
construction in accordance with the final design drawings and specifications .
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
·•
-ii
..
..
..
October 21, 2016
P/W 1607-03
REFERENCES
Page 20
Report No. 1607-03-B-2
American Concrete Institute, 2002, Building Code Requirements for Structural Concrete (AC/3 I BM-02) and
Commentary (AC/ 3/BRM-02), ACI International, Farmington Hills, Michigan.
American Society for Testing and Materials (2008), Annual Book of ASTM Standards, Section 4, Construction,
Volume 04.08, Soil and Rock(/), ASTM International, West Conshohocken, Pennsylvania.
California Code of Regulation, Title 24, 2013 California Building Code, 3 Volumes.
California Emergency Management Agency, 2009, Tsunami Inundation Map for Emergency Planning, Point
Loma Quadrangle, County of San Diego, California, Scale 1 :24,000.
Jennings, C.W., and Bryant, W.A., 2010, Fault Activity Map of California: California Geological Survey,
California Geologic Data Map No. 6, Scale 1 :750,000.
Kennedy, M.P., and Tan, S.S., 2008, Geologic Map of the San Diego 30' x 60' Quadrangle, California
Regional Geologic Map Series, Scale 1: 100,000, Map No. 3, Sheet 1 of 2 .
San Diego Region, Model BMP Design Manual for Permanent Site Design, Storm Water Treatment and
Hydromodification Management, February 2016.
United States Geological Survey, 2010 Ground Motion Parameter Calculator v. 5.1.0., World Wide Web,
http://earthquake.usgs.gov/designmaps/us/application.php .
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
APPENDIX A
FIELD AND LABORATORY DATA
ADV AN CED GEOTECHNICAL SOLUTIONS, INC., 2016
•
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
APPENDIX A
I
FIELD AND LABORATORY DATA
ADVANCED GEOTECHNICAL SOLUTIONS, INC., 2016
.. ADVANCED GEOTECHNICAL SOLUTIONS, INC •
..
...
..
eAGS BORING NUMBER HS-1
PAGE 1 OF 1
ADVANf,ED GEOUCHNlfAl SOLUTIONS, IN(;.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT NUMBER 1607-03 PROJECT LOCATION Carlsbad
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 62 ft HOLE SIZE 8 inch
DRILLING CONTRACTOR Baja Exploration GROUND WATER LEVELS:
DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --
LOGGED BY JAC CHECKED BY JAC AT END OF DRILLING ----·
NOTES AFTER DRILLING --
w ~ I-en ~ w~ z z C) a. enw w I-0 J: >-a:: a::-z I-en
i=~ :i:0 en 1-W s: I-::> 1-~ ::> I-0 z~ w I-~ C) wee 0Z....J zu 1-Z ~ 8~ I-<( ii= a. ii= a.o MATERIAL DESCRIPTION >-w-~....J en ....J'.:2, ....J ::> <( ::> .3, enW a:: w 0 ::> a.::> coo> -1-a:: w ....J (.') ~z ()~ it: oz ::> en J: w <( '.:2:0 I-w I-en 0 C) <( z 0 0 en u:::
~
[':,66:'. n Artifical fill undocumented (afu)f,C approximately 2 inch/
r -with 3 inch of base
(.'.)
0 . ,__§9__ -@ 0.5 ft, Old Paralic Deposits (Qop6),SIL TY
ca (/) ...J Cl: ('j
0 z ~ (.'.)
0 ill
"' 0 ..:. g
iii t; w ~ Q. i::: z ~ w ...J >-z w ~ >-z w ::;; ::, (.) 0 8 :::;
ID ::,
Q. ii, Cl: w
(/) ;l 0
" 0 N
0 "' 0)
S;
(!) g
(.'.) z i,: 0 ID
~
-
f--
r ___L
f--
~ -
->--
---
f-__19_
r -
~
-
-1L
-
~ -
--
f--
SANDSTONE, medium to fine grained, red brown, dry
@ 2.5 ft, slightly moist, freshening
@ 3.0 ft, SIL TY SANDSTONE, medium to fine grained,
slightly moist, moderately hard
@ 5.0 ft, SANDSTONE , medium to coarse grained, red to
brown, slightly moist, moderately hard to hard
-@ 7.0 ft SANDSTONE, medium grained, light tan, ----
freshening
@ 14.0 ft SANDSTONE, medium to coarse grained, tan to
light brown, slightly moist, moderately hard, gravel 318th inch
n!o 1 /2 inch-----------------_ _ ----__ /
@ 16.5 ft SANDSTONE, becoming saturated, interbedded
CLAY, very moist to saturated, hard
@ 19.0 ft, Santiago Formation (Tsal,CLAYSTONE, gray,
\ moist, moderately hard
@ 19.5 ft, CLA YSTONE, gray, moist to saturated, soft I
Total Depth= 19.75 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
BU Shear, Re molded Consol, El
MC 36/3" 86 5.0 ;:,near,
MC 50/3" Re molded Consol
If;PT
-------
15-18-21
(39) --
IisPT 20-21-38
(59)
lsPT 21-32-5
(37)
..
•
>-0 (!)
ID
:'.S en :,
g en >-z c3 ..,.
0 N
0 "' a,
"' >
(!) g
(!) z ii: 0 ID en ~
a A GS
BORING NUMBER HS-2
PAGE 1 OF 1
AD11MIC.£0 GEOT£CHNK:AL SDLUllONS, INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT NUMBER 1607-03 PROJECT LOCATION Carlsbad
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 64 ft HOLE SIZE 8 inch
DRILLING CONTRACTOR Baja Exploration GROUND WATER LEVELS:
DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING --
LOGGED BY JAC CHECKED BY JAC AT END OF DRILLING ---
NOTES AFTER DRILLING --
e:, 1--Cl) w ~ w~ z z c.. Cl)W ~ w 1--0 (.) >-0::: o:::~ z 1--Cl)
~£
J: :i::c_, Cl) 1--W ~1--:::, !::c ::,I--0 z~ w 1--~ (.) wco 0z....1 1--Z ~ 8~ 1--C..¢:: c..o Cl) MATERIAL DESCRIPTION ....I~ ....I::, <I'. zu CIJw 0::: >~ w~ ~....I ::, C..::, coo> ::, .e -1--0::: w w 0 Oz Cl) ....I (!) ~z (.) ~ >-~o ::, w J: w <I'. 0::: ~ 1--Cl) 0 (.) z 0 0 Cl) ii:
~ SM i\ Artificial Fill Undocumented (afu),0-4 inch CONCRETE 1
@ 4 inch, Old Paralic Deposits (Qop6),SANDSTONE,
SC medium to coarse grained, red brown, slightly moist, soft to
moderately hard
-@ 3.0 ft SIL TY SAND, medium to coarse grained, red
~ brown, slightly moist, dense
-@ 5.0 ft, SANDSTONE, medium to coarse grained, red
r ____§_ brown, moist, hard
@ 7.5 ft, medium to coarse grained, light tan, slightly moist,
~MC 21-31-39 119 4.3 31 r -hard (70) @ 8.5 ft, CLAYSTONE, coarse grained, moist to very moist,
r -soft to moderately hard
--
~ -
___ J_Q_ ___
-@ 10.0 ft, SIL TY SANDSTONE, medium to fine grained, tan-
II[sPT
~----.
12-14-14
-r -to red brown, moist to very moist, moderately hard (28)
@ 12.0 ft, SIL TY SANDSTONE, medium to fine grained, --medium brown, moist to very moist, hard to very hard, (Tight
--Drilling)
~f--
_ _J__§__
@ 17.5 ft, SILTY SANDSTONE, medium to fine grained, tan H MC 15-28 103 22.8 103 --to gray, moist to very moist, hard 9MC 50/3" @18.0 ft, LAG DEPOSIT, coarse grained, very moist to
-r saturated, firm
-,--
~~ -
-~ @ 20 ft, Santiago Formation (Tsa),CLAYSTONE, dark ~-Q_, __ 50/5H_ 108 18.9 99 Shear,
-,--green, very moist to saturated, hard Re molded
Consol
Total Depth= 21.5 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
-, a. (!)
0 <( al U) -' O'. <( ()
0 z ~ (!)
0 0 0:,
"' 0 I'-0 "' iii f-() w
0 O'. a. F'. z 13 s: w -' f-z w ~ f-z w ::. ::, () 0 0 u ::i al ::, a. in O'. w U) ;e
0
~ N ;!
~ ~ 0
e.'.. 0 (!)
al <( -' ..
U) ::,
0 f-U)
f-z ... 13 ... ;;
N
0 "' 0,
"' >
(!) 0 -'
(!) z a:: 0 al
U)
(!) <( ..
a A GS BORING NUMBER HS-3
i\DVMICfD G£0l£CHNlfAL SOI.IJTIONS, INC.
CLIENT McKellar McGowan
PROJECT NUMBER 1607-03
PROJECT NAME 800 Grand Carlsbad
PROJECT LOCATION Carlsbad
PAGE 1 OF 1
~-~--~-~----~-~-~ ~-----------------
DATESTARTED~9~/1~0~/1~6~---COMPLETED ~9~/1~0~/1~6 __ _ GROUND ELEVATION~6~0~ft~-~ HOLE SIZE ~8~i~n=ch~----
DRILLING CONTRACTOR_B~a~ja_E~xp_lo_r~at_io_n ________ _ GROUND WATER LEVELS:
DRILLING METHOD~H~o=ll=ow~S=te=m~A=u=ge=r _________ _ AT TIME OF DRILLING_----------------~
LOGGEDBY~J_A_C _____ _ CHECKED BY JAC ------AT END OF DRILLING_-_-_______________ _
NOTES ____________________ _ AFTER DRILLING_-_-______________ _
z 0
~2 >~ w ...J w
J: t-~ Q.,1= w~
0
60 0
+-
-~
r
,-
55 5
(/)
()
(/) ::>
MATERIAL DESCRIPTION
_l_J_ SM ~ Artificial Fill Undocumented lafu)~ inch AC _ ____r-
@ 0.5 ft, Old Paralic Deposits (Qop6)plL TY
SANDSTONE, medium to dark brown, slightly moist,
moderately hard
@ 1.0 ft SANDSTONE, medium to fine grained, red brown,
moist, moderately hard
Total Depth= 6.0 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
w Q.
~ffi wco
...J~
Q. ::> :::i:z <( (/)
i-..: w~ (/)W ~ o:::~ ~ I-::> 1-~ ::> I-0Z...J zo 1-Z ...J ::> <( ::> .e, (/)w coo> -I-
()~ >-oz
0::: :::i:O 0 ()
~ ~
z
0 .:: <(
0::: ::> ~ (/)
I-z w I-z 8l
(/) w z u::
(/) I-(/) w l-o::: w J: l-o
·"
..
N N ~
... ;;
N g
en
5;
"' g
"' z a'. 0 a,
U) ~
a A GS BORING NUMBER HS-4
PAGE 1 OF 1
ADVANCED GEOtf('AINICAL SOLUTIONS, INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT NUMBER 1607-03 PROJECT LOCATION Carlsbad
DATE STARTED 9/10/16 COMPLETED 9/10/16 GROUND ELEVATION 61 ft HOLE SIZE 8 inch
DRILLING CONTRACTOR Baja Exploration GROUND WATER LEVELS:
DRILLING METHOD Hollow Stem Auger AT TIME OF DRILLING ---
LOGGED BY JAC CHECKED BY JAC AT END OF DRILLING --
NOTES AFTER DRILLING -
w ~ I-._: w~ e.... z Cl) z C) a.
Cl)W s w I-0 J: >-0:: o::~ z I-Cl)
~£ i\9 Cl) 1-W st-=> t::.;:::-::> I-0 z w t-~ C) wco 0z.....1 1-Z ~ 0~ I-a..i= a.o MATERIAL DESCRIPTION z (.) >~ w~ ~....I
Cl) ....J::i!: .....1::><l'. ::>~ C/)w C) e.... 0:: ::> a.::> coo> -1-w 0 oz 0:: Cl) w
....I (!) ::i!:z ()~ >-::i!:O ::> w J: w <l'. 0:: ~ z I-Cl) 0 C) u:: 0 0 Cl)
_§Q_,_ ~ SM ~ Artifical Fill Undocumented (afu)3 inches AC over 3
inches base
-r -@ 0.25 ft SIL TY SAND, medium to fine grained, tan to red r
\ brown, slightly moist, dense -~----
-,-@ 0.5 ft Old Paralic Deeosit (Qol,!6} SANDSTONE
-r ii medium to fine grained, red brown, slightly moist,
moderately hard r
-~ @ 5.0 ft SANDSTONE, medium to coarse grained, light tan
___§§_r to red brown, slightly moist, hard
IISPT
12-11-12 Sieve @ 6.0 ft SANDSTONE, medium to fine grained, light tan, (23)
-,-slightly moist, moderately hard
r
f--
-~J_Q___
-@ 10.0 ft SANDSTONE, medium grained, dark brown, .
~M;-
-----
~5Q-r 23-47-50 117 7.6 51 23 slightly moist, soft (97) @ 12.0 ft SANDSTONE, medium to fine grained, brown to -r dark brown, moist, moderately hard to hard
-r (hard drilling)
@ 13.0 ft occasional 4 inch gravel
-f--
-~
---1§_,_ @ 15.0 ft lnterbedded SAND, medium to fine grained, tan to
I)sPT 12-12-20 gray brown, saturated, dense (32)
@ 17.5 ft LAG Deposit, 3/8th-3/4th inch diameter r
r @ 18.0 ft, Santiago Formation (Tsai.SANDSTONE,
medium to coarse grained, saturated, very hard ~MC 24 109 20.5 108
20 \MC 50/2"
Total Depth = 20.0 Feet
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
... 0 (!)
~
(/) :::,
0 ... (/) ... z i5
~ 0 N g
"' "' >
(!) 9
(!) z 0:: 0 ID
(/)
~AGS BORING NUMBER TB-1
ADVi\N('.ED GEDTECHNIC'AL SOUJllONS, INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECT LOCATION Carlsbad
PAGE 1 OF 1
PROJECTNUMBER_1_6~07~--03 _____________ _ -------------------
DATESTARTED~9~/~10~/1~6~---COMPLETED ~9~/1~0~/1=6 __ _
DRILLING CONTRACTOR_N_a~t_iv_e~D_r_ill_in~g __________ _
GROUND ELEVATION~6=6~ft~--
GROUND WATER LEVELS:
HOLE SIZE ~6~i~nc=h~----
DRILLING METHOD_T~r=io=,o=d _____________ _ AT TIME OF DRILLING_----------------~
LOGGEDBY~F~E~-----
NOTES
CHECKED BY ~J~A_C ___ _ AT END OF DRILLING_-_--______________ _
z
0 ~~ <l'.~ >~ w ...J w
_§§__
-
----------------------AFTER DRILLING_----------------~
() J: f-~ :i\.9 Cl..~ o..o w~ ~...J 0 (.!)
0
-~
-
(/)
()
(/)
:::>
SM
MATERIAL DESCRIPTION
Artificial Fill Undocumented (afu)SIL TY SAND, medium
~ grained, brown, dry, loose, some rootlets ;-
@ 1 ft Old Paralic Deposits (Qop6)S::LA YEY
SANDSTONE, fine grained, reddish brown, slightly moist,
moderately soft, some silt
@ 4 ft SIL TY SANDSTONE, fine grained, reddish brown,
moist to slightly moist, soft, trace olive mottling, trace clay
@ 5.0 ft CLAYEY SANDSTONE, fine grained, reddish
yellow and light yellowish brown, slightly moist to moist,
moderately hard, some olive mottling
@ 8.0 ft CLAYEY SANDSTONE, fine grained, pale olive,
moist, moderately hard, some silt
@ 14.0 ft SANDSTONE, fine to coarse grained, yellowish
\
brown and light olive, saturated, moderately soft, friable, /
trace silt
Total Depth= 16.0 Feet
Saturated at 14.0 ft
Backfilled with Cement and Bentonite Grout per San Diego
County
w Cl.. >-c::: f-W wca ...J~
Cl..::> ~z <l'. (/)
~ MC
"""" MC
~ MC
ww
~f-:::> 02...J ...J:::><l'. cao>
()~
18-32
30/4"
8-11-14
(25)
~ ~ ~ ~ w~ z c:::~
f-~ :::> f-0 zo r z ~
:::> .9: ww <l'. -f-c::: >-oz :::> c::: ~o ~ 0 ()
(/)
123 6.0 49
110 8.3 45
72
H MC 22-33 108 19.6 101
-=-. MC 50/5"
f-z w f-z~ 8~
(/) w z u:::
(/)
f-(/) w r c::: w J: f-0
-Shear,
Re molded
Consol
~'--~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.... 0 "' iii >-(,) w cl Cl'. a. ,:: z c3 s: w ...J >-z w
ill >-z w ::; ::::,
(,) 0 8 :::; a, ::::, a. 1i5 Cl'. w rn :e (.)
N N ;!
~ ;:;. 0
>-0 (!)
a, s rn ::::,
0 >-rn >-z c3 ... ;;
N
0 <')
0,
<') > (!)
0 ...J
(!) z a'. 0 a,
rn (!) <(
eAGS BORING NUMBER TB-2
PAGE 1 OF 1
ADIIMICEO GtOTECHNICAL SOLllllONS, INC.
CLIENT McKellar McGowan PROJECT NAME 800 Grand Carlsbad
PROJECTNUMBER_1~6=0~7-~0~3 ____________ _ PROJECT LOCATION_C~a=r=ls=ba=d~-------------~
DATESTARTED~9~/~10~/1~6~---COMPLETED ~9~/1~0~/1~6 __ _ GROUND ELEVATION~6~1~ft~--
GROUND WATER LEVELS:
HOLE SIZE ~6~i~nc~h ____ _
DRILLING CONTRACTOR_N_a_t1_·v_e_D_ri_lli~ng~---------
DRILLING METHOD_T~r=ip~od~---------------AT TIME OF DRILLING_---------------~
LOGGED BY FE --------CHECKED BY _J_A~C ___ _ AT END OF DRILLING_-_--_____________ _
NOTES _____________________ _ AFTER DRILLING_-_-_______________ _
z
0 ~~ >!S
UJ ....J UJ
>-
::c I-~ C..<1= w~
0
0
___j_Q -
(/)
(..)
(/)
::::>
SM
MATERIAL DESCRIPTION
\
TOPSOIL SIL TY SAND, fine grained, brown, slightly
moist, loose, abundant roots ' '----------'--------------'! @ 0.5 ft Old Paralic Deposits (Qop6lSIL TY
UJ c.. (/)W >-0:: I-UJ :s: I-::::> wa:J 02....J ....J~ ....J ::::> <{ C..::::> mo> ~z (..)~ <{ (/)
~ w~ o::~
t-~ ::::> I-zu 1-Z
::::> .3, (/) UJ -1-
~ oz ~o 0 (..)
SANDSTONE, yellowish red, slightly moist, soft, moderately
weathered, roots to 3 ft
@ 3.5 ft moderately hard, less weathered
~ MC 10-15-22 112 5.3 (37)
@4.0 ft SILTY SANDSTONE, fine grained, reddish brown, U MC 15-21-22 108 4_9 slightly moist, moderately hard, trace clay, roots to 6ft r, (43)
@ 5.0 ft SANDSTONE, fine grained, light yellowish brown to f----'~----j1-------1
reddish yellow, dry to slightly moist, moderately hard, some
silt, friable
,R. e.., z 0 ~ 0:: ::::> ~ (/)
31
25
I-z UJ I-z~ 8~
(/)
UJ z u:::
(/)
I-(/)
UJ I-
0:: UJ ::c I-0
Shear, Remolded Consol Consol
50 ~ ~ 13-15:22 108 4.5 23 1-"'.:::.....i~~.1.-~'--~--'---:T~o~ta71=D-ep~t~h-=~171~.0~F~e-et:--~~~~~~~~~~--t,:it',-:'~~~/.~4£0)~_J-'-.=-::..;._;.=..,._.:;.::....;~~~~~~---,
No Groundwater Encountered
Backfilled with Cement and Bentonite Grout per San Diego
County
Advanced Geotechnical Solutions, Inc.
MOISTURE CONTENT I DRY DENSIT' ( INTACT SAMPLES)
D-2216, D1557
EXCAVATION TB-1 TB-I TB-1 TB-1
DEPTH 2' 5' 10' 15'
SOIL Redish Redish Redish Light
Brown Brown Brown Brown
Silty Sand Silty Sand Silty Sand Fine to
Coarse
Sand
LENGTH 6 5 5 5
TUBE+W. SOIL 1222.7 945.2 1025.9 1007.5
TUBE 267.9 223.3 223.3 223.3
W.SOIL 954.8 721.9 802.6 784.2
FACTOR 0.01609 0.01341 0.01341 0.01341
W.DENSITY 130.71 118.57 131.83 128.81
CUP NO. 75 68 86 71
CUP+W. SOIL 326.64 279.67 251.38 285.15
CUP+D.SOIL 308.61 258.92 230.03 239.69
MOIST. LOSS 18.03 20.75 21.35 45.46
CUP 8.26 8.40 8.24 8.01
D. SOIL 300.35 250.52 221.79 231.68
MOIST. CONT. 6.00 8.28 9.63 19.62
DRY DENSITY 123.31 109.50 120.25 107.68
DEG.SATUR. 44 42 65 94
EXCAVATION HS-1 HS-2 HS-2 HS-2
DEPTH 5' 5' 15' 20'
SOIL Redish Redish Light to Light Gray
Brown Brown Dark Gray Silty Fine
Silty Fine Silty Fine Sand Sand
Sand Sand
LENGTH 4 6 6 6
TUBE+W. SOIL 774.7 1175.2 1193.3 1209.3
TUBE 223.3 267.9 267.9 267.9
W.SOIL 551.4 907.3 925.4 941.4
FACTOR 0.01341 0.01609 0.01609 0.01609
W.DENSITY 90.57 124.20 126.68 128.87
CUP NO. 68 75 88 76
CUP+W.SOIL 199.56 322.25 305.39 180.32
CUP+D. SOIL 190.49 309.40 250.24 152.96
MOIST.LOSS 9.07 12.85 55.15 27.36
CUP 8.48 8.34 8.13 8.06
D. SOIL 182.01 301.06 242.11 144.90
MOIST. CONT. 4.98 4.27 22.78 18.88
DRY DENSITY 86.27 119.12 103.18 108.40
DEG. SATUR. 14 28 97 92
PROJECT 800 Grand
~~~~~~~~~~~~-
Fl LE NO. 1607-03
~~~~~~~~-
BY H-M DATE 9/12/2016
TB-2 TB-2 TB-2
2' 5' 10'
Redish Redish Medium
Brown Brown Brown
Silty Fine Silty Fine Sand
Sand Sand
4 5 6
752.9 915.3 1090.0
178.6 223.3 267.9
574.3 692.0 822.1
0.01073 0.01341 0.01609
117.91 113.66 112.54
3 71 86
260.80 123.45 275.21
248.15 118. JO 263.72
12.65 5.35 11.49
8.03 8.03 8.34
240.12 110.07 255.38
5.27 4.86 4.50
112.01 108.40 107.70
28 24 22
HS-4 HS-4
10' 18.5'
Dark Olive Gray
Brown Sand Some
Silty Sand Silt Stone
6 6
1186.9 1225.1
267.9 267.9
919.0 957.2
0.01609 0.01609
125.81 131.04
93 4
290.57 322.45
270.66 269.02
19.91 53.43
8.24 8.18
262.42 260.84
7.59 20.48
116.93 108.76
46 101
'"'
..
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
CONSOLIDATION • ASTM D2435
Project Name: 800 Grand Excavation: TB-2
~~~~~~~~-~~~~~~~~
Location: Depth: 5'
~~~~~~~~-~~~~~~~--Project No: 1607-03
~~~~~~~~-
Des c rip ti on: Silty Fine Sand
Date: 9/13/2016
--.ft. -C:
0 ; ca :E
0 Ill C: 0 (J
0.1
1
-1
Test Description:
Water Content, w
Void Ratio, e
Saturation, S
Dry Density (pcf)
Wet Density (pcf)
Consolidation-Pressure Curve
Normal Pressure (ksf)
1 10
Before Test After Test
4.9% 17.5%
0.65 0.60
20% 78%
102.3 105.0
107.2 123.4
By: HM
100
ADVACED GEOTECHNICAL SOLUTION. INC.
EXPANSION INDEX TEST ASTM (04829)
Project Name: BOO Grand Location: ________ _ Excavation: HS-1 ~--------Depth: 2-5'
File No: 1607-03 Description: Silty Sand ~~-------Date ---------.,, SAMPLE PREPARATION 1y: -B HM
PARAMETER FORMULA UNITS DATA
Ring Volume A cf 0.007268
Specific Surcharge psf 144
2-lb Sample Moist B % 7.3
Wt. Ring C g 194.4
Wt. Ring+ Wet Soil D g 619.4
Wt. Wet Soil E = D-C g 425
Dry Density F pcf 120.04
Initial Saturation G =(Bx 2.7 x F) I (2.7 x 62.4 -F) % 49
FINAL SAMPLE INFORMATION
Wt. Ring+ Tare+ Wet Soil H g 733.5
Wt. Ring + Tare + Drv Soil I g 677.2
Tare J no. 19
Wt. Tare K g 98.8
Wt. Moisture Loss L = H - I g 56.3
Wt. DrvSoil M=I-C-K g 384
Final Moisture Content N = 100 x {LI M) % 14.7
Final Saturation 0 = (N x 2.7 x F) I (2.7 x 62.4 -F) % 98.09
Ring Volume After Test P = (R - S + 1) x 0.08722 / 12 cf 0.00735
TEST INFORMATION
PROPOSED READINGS FORMULA DATE TIME UNITS
LOAD APPLIED
0 minute Q 9/15/2016 12.30 PM 0.5431
10 minute R 9/15/2016 12.40 PM 0.5409
11 minute WATER ADDED
s 9/16/2016 1.00 PM 0.5527
EXPANSION INDEX El = 1000 x (S -R) 12 Low
INITIAL INITIAL INITIAL FINAL FINAL FINAL
DRY MOISTURE SATURA-SWELL EXPANSION DRY MOISTURE SATURA-
DENSITY CONTENT TION (%) INDEX DENSITY CONTENT TION
\ C:/, l'+v'+ }I
F (pcf) B (%) G (%) El /10 (El) (100+N)x10 N (%) 0 (%)
" 120.04 7.3 48.8 1.2 12 118.63 14.7 98.1
,.
Advanced Geotechnical Solutions, Inc.
MAXIMUM DENSITY
ASTM D-1557
Excavation: HS-1
Depth 2-5 •
Project Name: 800 Grand Location: _______ _
File No: 1607-03 Description: Dark Brown Silty Sand
Date: 9/17/2016
Sieve Size
Mold Size
No. of Layers
Test point number
Wt. wet soil + mold
Wt. wet soil + mold
Wt. of mold
Wt. wet of soil
Wet density
Dry density
4
4"
5
q
lbs
lbs
lbs
pcf
pcf
Moisture Determination (Oven)
Container number
Wt. wet of soil+tare g
Drv wt. soil+tare q
Tare wt. I g
Wt. of moisture g
Dry wt. of soil q
Moisture Content g
135.0
130.0
1
3986.3
8.78
4.10
4.68
140.41
132.24
12
264.5
249.61
8.62
14.89
240.99
6.18
% Retained None ----Method A By:
2 3 4
4053.1 4072.7 4051.2
8.93 8.97 8.92
4.10 4.10 4.10
4.83 4.87 4.82
144.83 146.12 144.70
134.79 134.44 130.50
71 8 3
282.3 266.3 285.4
263.3 245.7 258.2
8.24 8.55 8.24
19.00 20.60 27.20
255.06 237.15 249.96
7.45 8.69 10.88
Max Density
H-M ----
100.0 ,1.-.............. _ ..... _ _.._ ....................... _~ ................................ -. ................. ~ .... --f
0.0 5.0 10.0
Maximum Density 135.0 pcf
15.0
Moisture%
20.0 25.0
Optimum Moisture 8.0 % ----
30.0
Samples Tested 1 2
Boring ID HS-1 HS-1
Depth (in/ft.) 2-5' 2-5'
Initial Dry Density (pcf) 121.5 121.5
Initial Moisture Content (%) 8.00 8.00
Normal Stress {psf) 1000 2000
Maximum Shear Stress (psf) 1087 1802
Ultimate Shear Stress (psf) 963 1647
ASTM D3080
Vertical Deformation v. Displacement
0.06
0.05
0.04 .. ,
-0.02 -1000
--S-2000
-0.03 -4000
0.00 0.05 0.10 0.15 0.20 0.25
Displacement (in)
..
...
0 500 1000 1500 2000
3
HS-1
2-5'
121.5
8.00
4000
3169
3169
0.30
Peak Ultim.
Friction Angle, phi (Deg)~ ___ 3_s ..... , ___ 36--tl
Cohesion (psf) ..... __ 4_o_o .... __ 2_0-0
Remolded
Strain Rate (in/min): 0.005
Shear Stress v. Displacement
3500 --~ -10-00 --------------,
--S-2000
3000 -.!,-4000 ____ ..,....,.,~~~~::=._: __ ~
~
°;' 2000 1------------------1
"' e! ~
l; 1500 t---.... --,,,.---------------1 QI .r. "'
500
0 ~-~.-,....~~-'--'~~ ......... ~--'-~-'-~-'-.....-.-'-'-__,
0.00 0.05 0.10 0.15 0.20 0.25 0.,
Displacement (in)
Shear Stress
2500 3000 3500
Normal Stress (psf)
800 Grand, Remolded
4000 4500 5000 5500 60Q
Samples Tested 1 2
Boring ID HS-1 HS-1
Depth (in/ft.) 5' 5'
Initial Dry Density (pd) 99.74 98.86
Initial Moisture Content (%) 4.98 4.98
Normal Stress (psf) 1000 2000
Maximum Shear Stress (psf) 901 1957
Ultimate Shear Stress (psf) 901 1957
ASTM D3080
Vertical Deformation v. Displacement
0.06
0.05
0.04
;[ 0.03
C .g 0.02
"' e i 0.01
-0.02
-0.03
-0.04
0.00
4000
3500
3000
r;:: 2500 "' .e
"' "' f 2000 ~ ... IQ QI ~ 1500
1000
500
0
0
-e-2000
-6-4000
0.05 0.10 0.15 0.20 0.25
Displacement (in)
500 1000 1500 2000
3
HS-1
5'
105.13
4.98
4000
3293
3293
0.30
3500
3000
2500
~ ~ 2000
Ill ~ ~ :0 1500 cu .c Ill
1000
500
Shear Stress
0.00
Peak Ultim.
Friction Angle, phi (Deg), .... ___ 3_8-tl---38-11
Cohesion (psf) ...... __ 2_3_0.._ __ 2_30~
Sample Type: Remolded ~~~~~-------
Strain Rate (in/min): 0.005
Shear Stress v. Displacement
-1000
-e-2000
-6-4000 ---~~---------1
0.05 0.10 0.15 0.20 0.25 0.,
Displacement (in)
2500 3000 3500
Normal Stress (psf)
4000 4500 5000 5500 600
800 Grand, Intact
'"
Samples Tested 1 2 3 Peak Ultim.
Boring ID HS-2 HS-2 HS-2
Depth (in/ft.) 20' 20' 20'
Friction Angle, phi (Deg) ~---3_6t __ 3_6 ... ,
Cohesion (psf)._ ___ 2_s_o.._ __ 1_s__,o
Initial Dry Density (pcf) 99.09 105.9 98.51
Initial Moisture Content (%) 18.88 18.88 18.88 Sample Type: _____ R_em_o_ld_e_d ___ _
Normal Stress (psf) 1000 2000 4000
Maximum Shear Stress (psf) 994 1740 3169
Ultimate Shear Stress (psf) 963 1554 3169
ASTM D3080 Strain Rate (in/min): 0.005
Vertical Deformation v. Displacement Shear Stress v. Displacement
0.06 ~----------------~ 3500 ~-~ -~--------------.
0.05
0.04
-0.02
-0.03
-0.04
0.00
4000
3500
3000
;;:-2500 Ill .:!:
Ill Ill
f 2000 ~ ...
111 CII ~ 1500
1000
500
0
0
-1000
-2000
-.!,,--4000
0.05 0.10 0.15 0.20 0.25
Displacement (in)
500 1000 1500 2000
-1000
-2000
3000 --.!,,--4000 ----Jt.~~~~~~--J
0.30
~ °;' 2000
"' f ~
; 1500
QI ..c "'
500
0
Shear Stress
0.00
2500 3000 3500 Normal Stress (psf)
800 Grand, Intact
0.05 0.10 0.15 0.20 0.25 o.,
Displacement (in)
4000 4500 5000 5500 600
Samples Tested 1 z
Boring ID TB-1 TB-1
Depth (in/ft.) 10' 10'
Initial Dry Density (pcf) 109.29 127.88
Initial Moisture Content (%) 9.63 9.63
Normal Stress (psf) 1000 2000
Maximum Shear Stress (psf) 1181 3418
Ultimate Shear Stress (psf) 621 1616
ASTM D3080
Vertical Deformation v. Displacement
0.06
0.05
"' 0.04
~ ;[ 0.03
••
C _g 0.02 .. E ~ C
0.01
-0.02
-0.03
-0.04
0.00
4000
3500
3000
;;:-2500
"' .e:
"' "' ~ 2000 tii ... 111 ciJ ~ 1500
1000
500
0
0
-1000
-e-2000
-i!l--4000
0.05 0.10 0.15 0.20 0.25
Displacement (in)
500 1000 1500 2000
3
TB-1
10'
112.5
9.63
4000
2796
2579
0.30
4000
3500
3000
~ 2500 .!= .. .. f! 2000 ~ .. .. GI 6; 1500
1000
500
Shear Stress
0.00
Peak Ultim.
Friction Angle, phi (Deg), ..... ___ 2_3 ..... , ___ 32--11
Cohesion (psf) ...... __ 1_4_9_0 ___ 1_4 ..... 0
Sample Type: Remolded ------------
Strain Rate (in/min): 0.005
Shear Stress v. Displacement
---------------------1000
-e-2000
-i!l--4000 ---------------1
0.05 0.10 0.15 0.20 0.25 o.,
Displacement (in)
2500 3000 3500 4000 4500 5000 5500 600 Normal Stress (psf)
800 Grand, Intact
..
...
.. ..
Samples Tested 1 2
Boring ID TB-2 TB-2
Depth (in/ft.) 5' 5'
Initial Dry Density (pd) 102.95 101
Initial Moisture Content(%) 4.86 4.86
Normal Stress (psf) 1000 2000
Maximum Shear Stress (psf) 994 1926
Ultimate Shear Stress {psf) 777 1771
ASTM D3080
Vertical Deformation v. Displacement
0.06
0.04
-0.02
-0.03
0.00
4000
3500
;;:-2500
Ill .e:
Ill Ill
f 2000 ~ ... nl QI ~ 1500
1000
500
0 l
0
-1000 -·--·--··"''"' ......... _ .. ..
-2000
---.!r-4000
0.05 0.10 0.15 0.20 0.25
Displacement (in)
500 1000 1500 2000
3 Peak Ultim.
TB-2
5'
Friction Angle, phi (Deg)~ ___ 3_2-11i-----3--141
Cohesion (psf)._ ___ s_o_o ... __ 2_1 ...... s
105.76
4.86 Sample Type: Remolded ------------4000
2921
2890
Strain Rate (in/min): 0.005
Shear Stress v. Displacement
3500 -1000
-B-2000
3000 ---.!r-4000 -------,-.-,-------1
2500
1000
500
0.30 0.00 0.05 0.10 0.15 0.20 0.25 0.:
Displacement (in)
Shear Stress
2500 3000 3500
Normal Stress (psf)
4000 4500 5000 5500 600 I
800 Grand, Intact
..
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
PARTICLE SIZE ANALYSIS -ASTM D422
Project Name: 800 Grand
~~~~~~~~~
Excavation: HS-4
~~~~~~~~-
Location: 0
~~~~~~~~~
Depth: _5_' ______ _
Project No.: 1607-03
~~~~~~~~~
By: HM
Date: 6/17/16
Cobbles C. Gravel F. Gravel c. Sand Md. Sand F.Sand Silt Clay
100
90
80
70
60 e
tll) 50 C 'iii "' IV 40 Cl. ... C QI 30 u .. QI
Cl. 20
10
0
1000 100 10 1 0.1 0.01 0.001
Grain Size Grain Size
(in/#) (mm)
3" 76.20
2 1/2" 63.50
2" 50.80
1 1/2" 38.10
1 " 25.40
3/4" 19.05
1/2" 12.70
3/8" 9.53
#4 4.75
# 10 2.00
#20 0.85
#30 0.60
#40 0.425
# 50 0.30
#60 0.212
# 100 0.15
# 200 0.075
Hydro 0.0319
Hydro 0.0204
Hydro 0.0100
Hydro 0.0084
Hydro 0.0060
Hydro 0.0030
Hydro 0.0013
Amount
Passing (%}
100.00
#N/A
#N/A
81.86
#N/A
#N/A
31.85
23.21
18.68
17.34
16.01
14.67
12.01
10.67
9.34
Grain Size (mm)
Summary
% Gravel = 0.0
% Sand= 76.8
% Fines=
Sum=
LL=
PL=
Pl=
23.2
100.0
------------
Soil Type: ___ _
LABORATORY REPORT
Telephone (619) 425-1993 Fax 425-7917 Established 1928
CLARKSON LABORATORY AND SUPPLY INC.
350 Trousdale Dr. Chula Vista, Ca. 91910 www.clarksonlab.com
A N A L Y T I C A L A N D C O N S U L T I N G C H E M I S T S
Date: September 30, 2016
Purchase Order Number: 1607-03
Sales Order Number: 32907
~ Account Number: ADVG
""'
'"
..
..
4
To: *-------------------------------------------------*
Advance Geotechnical Solutions Inc
9707 Waples Street Ste. 150
San Diego, CA 92121
Attention: Paul Deresi
Laboratory Number: S06150 Customers Phone: 850-3980
Sample Designation: *-------------------------------------------------*
One soil sample received on 09/23/16 at 1:05pm,
from Project# 1607-03 marked as HS-1@ 2-3 ft.
Analysis By California Test 643, 1999, Department of Transportation
Division of Construction, Method for Estimating the Service Life of
Steel Culverts.
pH 7.5
Water Added (ml)
10
5
5
5
5
5
5
5
5
37 years to perforation for a 16 gauge
48 years to perforation for a 14 gauge
67 years to perforation for a 12 gauge
85 years to perforation for a 10 gauge
104 years to perforation for a 8 gauge
Water Soluble Sulfate Calif. Test 417
Water Soluble Chloride Calif. Test 422
Rosa M. Bernal
RMB/ilv
metal
metal
metal
metal
metal
Resistivity (ohm-cm)
culvert.
culvert.
culvert.
culvert.
culvert.
5700
2800
2100
1800
1700
1700
1600
1900
2200
0.003% (30ppm)
0.010% (96ppm)
APPENDIXB
GENERAL EARTHWORK SPECIFICATIONS
AND GRADING GUIDELINES
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
..
..
...
GENERAL EARTHWORK SPECIFICATIONS
I. General
A. General procedures and requirements for earthwork and grading are presented herein. The earthwork
and grading recommendations provided in the geotechnical report are considered part of these
specifications, and where the general specifications provided herein conflict with those provided in the
geotechnical report, the recommendations in the geotechnical report shall govern. Recommendations
provided herein and in the geotechnical report may need to be modified depending on the conditions
encountered during grading.
B. The contractor is responsible for the satisfactory completion of all earthwork in accordance with the
project plans, specifications, applicable building codes, and local governing agency requirements. Where
these requirements conflict, the stricter requirements shall govern.
C. It is the contractor's responsibility to read and understand the guidelines presented herein and in the
geotechnical report as well as the project plans and specifications. Information presented in the
geotechnical report is subject to verification during grading. The information presented on the exploration
logs depicts conditions at the particular time of excavation and at the location of the excavation.
Subsurface conditions present at other locations may differ, and the passage of time may result in
different subsurface conditions being encountered at the locations of the exploratory excavations. The
contractor shall perform an independent investigation and evaluate the nature of the surface and
subsurface conditions to be encountered and the procedures and equipment to be used in performing his
work.
D. The contractor shall have the responsibility to provide adequate equipment and procedures to
accomplish the earthwork in accordance with applicable requirements. When the quality of work is less
than that required, the Geotechnical Consultant may reject the work and may recommend that the
operations be suspended until the conditions are corrected.
E. Prior to the start of grading, a qualified Geotechnical Consultant should be employed to observe
grading procedures and provide testing of the fills for conformance with the project specifications,
approved grading plan, and guidelines presented herein. All remedial removals, clean-outs, removal
bottoms, keyways, and subdrain installations should be observed and documented by the Geotechnical
Consultant prior to placing fill. It is the contractor's responsibility to apprise the Geotechnical Consultant
of their schedules and notify the Geotechnical Consultant when those areas are ready for observation.
F. The contractor is responsible for providing a safe environment for the Geotechnical Consultant to
observe grading and conduct tests .
II. Site Preparation
A. Clearing and Grubbing: Excessive vegetation and other deleterious material shall be sufficiently
removed as required by the Geotechnical Consultant, and such materials shall be properly disposed of
offsite in a method acceptable to the owner and governing agencies. Where applicable, the contractor may
obtain permission from the Geotechnical Consultant, owner, and governing agencies to dispose of
vegetation and other deleterious materials in designated areas onsite.
B. Unsuitable Soils Removals: Earth materials that are deemed unsuitable for the support of fill shall be
removed as necessary to the satisfaction of the Geotechnical Consultant.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
C. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells,
pipelines, other utilities, or other structures located within the limits of grading shall be removed and/or
abandoned in accordance with the requirements of the governing agency and to the satisfaction of the
Geotechnical Consultant.
D. Preparation of Areas to Receive Fill: After removals are completed, the exposed surfaces shall be
scarified to a depth of approximately 8 inches, watered or dried, as needed, to achieve a generally uniform
moisture content that is at or near optimum moisture content. The scarified materials shall then be
compacted to the project requirements and tested as specified.
E. All areas receiving fill shall be observed and approved by the Geotechnical Consultant prior to the
placement of fill. A licensed surveyor shall provide survey control for determining elevations of
processed areas and keyways.
III. Placement of Fill
A. Suitability of fill materials: Any materials, derived onsite or imported, may be utilized as fill provided
that the materials have been determined to be suitable by the Geotechnical Consultant. Such materials
shall be essentially free of organic matter and other deleterious materials, and be of a gradation, expansion
potential, and/or strength that is acceptable to the Geotechnical Consultant. Fill materials shall be tested in
a laboratory approved by the Geotechnical Consultant, and import materials shall be tested and approved
prior to being imported.
B. Generally, different fill materials shall be thoroughly mixed to provide a relatively uniform blend of
materials and prevent abrupt changes in material type. Fill materials derived from benching should be
dispersed throughout the fill area instead of placing the materials within only an equipment-width from
the cut/fill contact.
C. Oversize Materials: Rocks greater than 8 inches in largest dimension shall be disposed of offsite or be
placed in accordance with the recommendations by the Geotechnical Consultant in the areas that are
designated as suitable for oversize rock placement. Rocks that are smaller than 8 inches in largest
dimension may be utilized in the fill provided that they are not nested and are their quantity and
distribution are acceptable to the Geotechnical Consultant.
D. The fill materials shall be placed in thin, horizontal layers such that, when compacted, shall not exceed
6 inches. Each layer shall be spread evenly and shall be thoroughly mixed to obtain near uniform moisture
content and uniform blend of materials.
E. Moisture Content: Fill materials shall be placed at or above the optimum moisture content or as
recommended by the geotechnical report. Where the moisture content of the engineered fill is less than
recommended, water shall be added, and the fill materials shall be blended so that near uniform moisture
content is achieved. If the moisture content is above the limits specified by the Geotechnical Consultant,
the fill materials shall be aerated by discing, blading, or other methods until the moisture content is
acceptable.
F. Each layer of fill shall be compacted to the project standards in accordance to the project specifications
and recommendations of the Geotechnical Consultant. Unless otherwise specified by the Geotechnical
Consultant, the fill shall be compacted to a minimum of 90 percent of the maximum dry density as
determined by ASTM Test Method: D1557-09.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
G. Benching: Where placing fill on a slope exceeding a ratio of 5 to 1 (horizontal to vertical), the ground
should be keyed or benched. The keyways and benches shall extend through all unsuitable materials into
suitable materials such as firm materials or sound bedrock or as recommended by the Geotechnical
Consultant. The minimum keyway width shall be 15 feet and extend into suitable materials, or as
recommended by the geotechnical report and approved by the Geotechnical Consultant. The minimum
keyway width for fill over cut slopes is also 15 feet, or as recommended by the geotechnical report and
approved by the Geotechnical Consultant. As a general rule, unless otherwise recommended by the
Geotechnical Consultant, the minimum width of the keyway shall be equal to 1/2 the height of the fill
slope.
H. Slope Face: The specified minimum relative compaction shall be maintained out to the finish face of
fill and stabilization fill slopes. Generally, this may be achieved by overbuilding the slope and cutting
back to the compacted core. The actual amount of overbuilding may vary as field conditions dictate.
Alternately, this may be achieved by back rolling the slope face with suitable equipment or other methods
that produce the designated result. Loose soil should not be allowed to build up on the slope face. If
present, loose soils shall be trimmed to expose the compacted slope face.
I. Slope Ratio: Unless otherwise approved by the Geotechnical Consultant and governing agencies,
permanent fill slopes shall be designed and constructed no steeper than 2 to 1 (horizontal to vertical).
J. Natural Ground and Cut Areas: Design grades that are in natural ground or in cuts should be evaluated
by the Geotechnical Consultant to determine whether scarification and processing of the ground and/or
overexcavation is needed.
K. Fill materials shall not be placed, spread, or compacted during unfavorable weather conditions. When
grading is interrupted by rain, filing operations shall not resume until the Geotechnical Consultant
approves the moisture and density of the previously placed compacted fill.
IV. Cut Slopes
A. The Geotechnical Consultant shall inspect all cut slopes, including fill over cut slopes, and shall be
notified by the contractor when cut slopes are started.
B. If adverse or potentially adverse conditions are encountered during grading; the Geotechnical
Consultant shall investigate, evaluate, and make recommendations to mitigate the adverse conditions.
C. Unless otherwise stated in the geotechnical report, cut slopes shall not be excavated higher or steeper
than the requirements of the local governing agencies. Short-term stability of the cut slopes and other
excavations is the contractor's responsibility.
V. Drainage
A. Back drains and Subdrains: Back drains and subdrains shall be provided in fill as recommended by the
Geotechnical Consultant and shall be constructed in accordance with the governing agency and/or
recommendations of the Geotechnical Consultant. The location of subdrains, especially outlets, shall be
surveyed and recorded by the Civil Engineer.
B. Top-of-slope Drainage: Positive drainage shall be established away from the top of slope. Site drainage
shall not be permitted to flow over the tops of slopes.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
C. Drainage terraces shall be constructed in compliance with the governing agency requirements and/or in
accordance with the recommendations of the Geotechnical Consultant.
D. Non-erodible interceptor swales shall be placed at the top of cut slopes that face the same direction as
the prevailing drainage.
VI. Erosion Control
A. All finish cut and fill slopes shall be protected from erosion and/or planted in accordance with the
project specifications and/or landscape architect's recommendations. Such measures to protect the slope
face shall be undertaken as soon as practical after completion of grading.
B. During construction, the contractor shall maintain proper drainage and prevent the ponding of water.
The contractor shall take remedial measures to prevent the erosion of graded areas until permanent
drainage and erosion control measures have been installed.
VII. Trench Excavation and Backfill
A. Safety: The contractor shall follow all OSHA requirements for safety of trench excavations. Knowing
and following these requirements is the contractor's responsibility. All trench excavations or open cuts in
excess of 5 feet in depth shall be shored or laid back. Trench excavations and open cuts exposing adverse
geologic conditions may require further evaluation by the Geotechnical Consultant. If a contractor fails to
provide safe access for compaction testing, backfill not tested due to safety concerns may be subject to
removal.
B. Bedding: Bedding materials shall be non-expansive and have a Sand Equivalent greater than 30.
Where permitted by the Geotechnical Consultant, the bedding materials can be densified by jetting.
C. Backfill: Jetting of backfill materials is generally not acceptable. Where permitted by the Geotechnical
Consultant, the bedding materials can be densified by jetting provided the backfill materials are granular,
free-draining and have a Sand Equivalent greater than 30.
VIII. Geotechnical Observation and Testing During Grading
A. Compaction Testing: Fill shall be tested by the Geotechnical Consultant for evaluation of general
compliance with the recommended compaction and moisture conditions. The tests shall be taken in the
compacted soils beneath the surface if the surficial materials are disturbed. The contractor shall assist the
Geotechnical Consultant by excavating suitable test pits for testing of compacted fill.
B. Where tests indicate that the density of a layer of fill is less than required, or the moisture content not
within specifications, the Geotechnical Consultant shall notify the contractor of the unsatisfactory
conditions of the fill. The portions of the fill that are not within specifications shall be reworked until the
required density and/or moisture content has been attained. No additional fill shall be placed until the last
lift of fill is tested and found to meet the project specifications and approved by the Geotechnical
Consultant.
C. If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as adverse weather,
excessive rock or deleterious materials being placed in the fill, insufficient equipment, excessive rate of
fill placement, results in a quality of work that is unacceptable, the consultant shall notify the contractor,
and the contractor shall rectify the conditions, and if necessary, stop work until conditions are
satisfactory.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
...
D. Frequency of Compaction Testing: The location and frequency of tests shall be at the Geotechnical
Consultant's discretion. Generally, compaction tests shall be taken at intervals not exceeding two feet in
fill height and 1,000 cubic yards of fill materials placed.
E. Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation
and horizontal coordinates of the compaction test locations. The contractor shall coordinate with the
surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can
detennine the test locations. Alternately, the test locations can be surveyed and the results provided to the
Geotechnical Consultant.
F. Areas of fill that have not been observed or tested by the Geotechnical Consultant may have to be
removed and recompacted at the contractor's expense. The depth and extent of removals will be
determined by the Geotechnical Consultant.
G. Observation and testing by the Geotechnical Consultant shall be conducted during grading in order for
the Geotechnical Consultant to state that, in his opinion, grading has been completed in accordance with
the approved geotechnical report and project specifications.
H. Reporting of Test Results: After completion of grading operations, the Geotechnical Consultant shall
submit reports documenting their observations during construction and test results. These reports may be
subject to review by the local governing agencies.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
...
DESIGN GRADE
') \.. EXISTING GRADE /'""' " / /,, ..__'-"I ... , /
' .. , /·,·' ' ... ' ENGINEERED FILL / ,
..__'....., . ~ ' / . ~....-'-........
.. ·· ,, ~ /· .•. ·i,
"-. / I ---· .,
..
' .. , / REQUIRED BENCHING .__ _ __,.. . ' , , .,
UNSUITABLE
BEARING MATERIAL
(REMOVE)
' , .. ,
, ._ --SUITABLE
• : ;: .~ BEARING MATERIAL
SUBDRAIN OPTION 1 OR 2
SEE DETAIL2
~-•.. ;•:'
--~ :::.c:S·I: PLACE SUBDRAIN AT LOWEST ...... GRADE WITHIN CANYON REMOVAL
CANYON SUBDRAIN PROFILE
DIRECT SOLID OUTLET PIPE TO
APPROVED DRAINAGE AREA PER
PROJECT CIVIL ENGINEER
CONSTRUCT DRAIN OUTLET
A MINIMUM 1-FOOT
CUTOFF WALL CONSISTING OF
GROUT, CONCRETE, BENTONITE
OR OTHER MATERIAL
APPROVED BY
ABOVE GRADE GEOTECHNICAL CONSULTANT
VER 1.0
••• •• I' ••••• I' •••••••••••• :; ::-.-::•::.: •::.: ··· .. ·.-:·· .. ·.-
... · ...... ·. ::.· ·. :: .. : ···.~ .. : .:•.•.
I< 20 FOOT MINIMUM )f( 5 FT.>!
MIN.
SOLID PIPE PERFORATED PIPE
NOTE: LOCATION OF CANYON SUBDRAINS AND OUTLETS
SHOULD BE DOCUMENTED BY PROJECT CIVIL ENGINEER.
OUTLETS MUST BE KEPT UNOBSTRUCTED AT ALL TIMES.
CANYON SUBDRAIN TERMINUS
8AGS CANYON SUBDRAIN
CUTOFF WALL
DIMENSIONS
DETAIL 1
NTS
,.. ADVANCED GEOTECHNICAL SOLUTIONS
12-INCH MINIMUM
ABOVE PIPE
APPROVED
FILTER
MATERIAL
6-INCHES MINIMUM,
ADJACENT TO AND
BELOW PIPE
OPTION 1
FILTER MATERIAL: _MINIMUM VOLUME OF
9 CUBIC FEET PER LINEAL
FOOT OF CAL TRANS
CLASS 2 PERMEABLE MATERIAL
APPROVED
12-INCH MINIMUM
ABOVE PIPE
·.· .....
FILTER --~, .. : ·. · .. ·· · APPROVED
DRAIN
MATERIAL FABRIC, WITH
6-INCH
OVERLAP
6-INCHES MINIMUM,
ADJACENT TO AND
BELOW PIPE
OPTION 2
DRAIN MATERIAL: MINIMUM VOLUME OF 9 CUBIC FEET
PER LINEAL FOOT OF 3/4-INCH MAX
ROCK OR APPROVED EQUIVALENT
SUBSTITUTE
FILTER FABRIC: MIRAFI 140 FILTER FABRIC OR
APPROVED EQUIVALENT SUBSTITUTE
PIPE: 6 OR 8-INCH ABS OR PVC PIPE OR APPROVED SUBSTITUTE WITH A MINIMUM
OF 8 PERFORATIONS (1/4-INCH DIAMETER) PER LINEAL FOOT IN
BOTTOM HALF OF PIPE
(ASTM 02751, SDR-35 OR ASTM 03034, SDR-35
ASTM 01527, SCHD. 40 OR ASTM 01785, SCHD. 40)
NOTE: CONTINUOUS RUN IN EXCESS OF 500 FEET REQUIRES 8-INCH DIAMETER PIPE
(ASTM 03034, SDR-35, OR ASTM 01785, SCHD. 40)
CANYON SUBDRAIN
DRAIN 2-FT. MIN
~t~~:l;~BRIC '(. <"I2-FT.
: : :·.·.·: · MIN -----::.-:~-o-. ·/ . . . . .. . -7-~ . ..,. .... .
4-INCH SOLID 2-INCH MIN
OUTLET PIPE BELOW PIPE
OPTION 1
DRAIN
MATERIAL
2-INCH MIN.
BELOW PIPE
DRAIN MATERIAL: GRAVEL TRENCH TO BE FILLED WITH 3/4-INCH MAX ROCK OR APPROVED EQUIVALENT
SUBSTITUTE
FILTER FABRIC: MIRAFI 140 FILTER FABRIC OR EQUIVALENT SUBSTITUTE WITH A MINIMUM 6-INCH OVERLAP
PIPE: 4-INCH ABS OR PVC PIPE OR APPROVED EQUIVALENT SUBSTITUTE WITH A MINIMUM
VER 1.0
11,AGS
OF 8 PERFORATIONS (1/4-INCH DIAMETER) PER LINEAL FOOT IN
BOTTOM HALF OF PIPE
(ASTM D2751, SDR-35 OR ASTM 03034, SDR-35
ASTM 01527, SCHD. 40 OR ASTM D1785, SCHD. 40)
BUTTRESS/STABILIZATION DRAIN
DRAIN SPECIFICATIONS
ADVANCED GEOTECHNIC.I\L SOLUTIONS
NTS
DETAIL 2
,,
....
-
CONSTRUCT DRAIN OUTLET
A MINIMUM 1-FOOT
ABOVE GRADE
CODE COMPLIANT
BLANKET FILL -AS REQUIRED BY
GEOTECHNICAL CONSULTANT
AND/OR CODE COMPLIANCE
(3 FOOT MIN.)
SETBACK, 15 FOOT MIN.~
~o~ ~ 0<?-J
o~c::f3
~--------~:--~
···::::~::~;~:::::::::::::~
BENCH WIDTH
VARIES
""' K ~ 2% -~ 4 FOOT MIN .
>I
VER 1.0
. . . . . -.. ·:::::.~·-:·.: :·. ·. ·. ·.·. ·. ·. ·. ·::. ·. 9 ~CH HEIGHT
TO~
2%MIN.
~WIDTH~
HEEL
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE 2 FOOT MIN.
HEEL 3 FOOT MIN.
WIDTH 15 FOOT MIN.
SEE DETAIL 2 FOR DRAIN SPECIFICATIONS
NOTES:
1. DRAIN OUTLETS TO BE PROVIDED EVERY 100 FEET
CONNECT TO PERFORATED DRAIN PIPE BY "L" OR 'T'
AT A MINIMUM 2% GRADIENT.
2. THE NECESSITY AND LOCATION OF ADDITIONAL
DRAINS SHALL BE DETERMINED IN THE FIELD
BY THE GEOTECHNICAL CONSULTANT. UPPER STAGE
OUTLETS SHOULD BE EMPTIED ONTO CONCRETE
TERRACE DRAINS.
3. DRAIN PIPE TO EXTEND FULL LENGTH OF
STABILIZATION/BUTTRESS WITH A MINIMUM GRADIENT
OF 2% TO SOLID OUTLET PIPES.
4. LOCATION OF DRAINS AND OUTLETS
SHOULD BE DOCUMENTED BY PROJECT
CIVIL ENGINEER. OUTLETS MUST BE KEPT
UNOBSTRUCTED AT ALL TIMES.
NTS
11,AGS STABILIZATION/BUTTRESS FILL DETAIL 3
ADVANCED GEOTECHNICAL SOLUTIONS
ill
* THE "CUT' PORTION OF THE SLOPE SHALL
BE EXCAVATED AND EVALUATED BY THE
GEOTECHNICAL CONSULTANT PRIOR TO
CONSTRUCTING THE "FILL" PORTION
ENGINEERED FILL
I<
4 FOOT MIN.
BENCH HEIGHT
/
/
>I
SUITABLE BEARING MATERIAL
SUITABLE
BEARING MATERIAL
VER 1.0
8AGS
~WIDTH~
NOTES:
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE: 2 FOOT MIN.
HEEL: 3 FOOT MIN.
WIDTH: 15 FOOT MIN.
1. THE NECESSITY AND LOCATION OF DRAINS
SHALL BE DETERMINED IN THE FIELD
BY THE GEOTECHNICAL CONSULTANT
2. SEE DETAIL 2 FOR DRAIN SPECIFICATIONS
FILL OVER CUT SLOPE
ADVANCED GEOTECHNICAL SOLUTIONS
DETAIL4
NTS
..
A 1:1 MINIMUM
PROJECTION FROM DESIGN
SLOPE TOE TO TOE OF KEYWAY ;.
RE-GRADE NATURAL SLOPE
WITH ENGINEERED FILL
~G G~p..O'c. / ~ , . ,
E.'i-\$\~ -:-· . -: . --: . ... ...... , _' ___ ......
_.. _.. . . . W'o\JE.\ , ·, -~-. . -~\_.\~~. , ,
. • . . . . . . . . . ... ~~E.~\ .. __ , __ __, . . . G ,,... . ..
· • / · · ~~~\~ .;. "' BENCH WIDTH
· • · · ~1p\-E. 'o. · ;. ' VARIES
I~ . . . .. /. . ..'.\$\}\" . . . . --. ' . . . . UY" . ; ~I( ---->I / . ;
VARIABLE • ' . /. . ·--4 FOOT MIN .
BACKCUT • Yf --BENCH HEIGHT
~ TOE
--~ HEEL 2%MIN. SUITABLE BEARING MATERIAL
K-WIDTH~
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE: 2 FOOT MIN.
HEEL: 3 FOOT MIN.
WIDTH: 15 FOOT MIN.
VER 1.0
aAGS
NOTES:
1. WHEN THE NATURAL SLOPE APPROACHES OR
EXCEEDS THE DESIGN GRADE SLOPE RATIO,
SPECIAL RECOMMENDATIONS ARE NECESSARY
BY THE GEOTECHNICAL CONSULTANT
2. THE GEOTECHNICAL CONSULTANT WILL
DETERMINE THE REQUIREMENT FOR AND
LOCATION OF SUBSURFACE DRAINAGE SYSTEMS.
3. MAINTAIN MINIMUM 15 FOOT HORIZONTAL WIDTH
FROM FACE OF SLOPE TO BENCH/BACKCUT
FILL OVER NATURAL SLOPE
I\OVI\NCED GEOTECHNICI\L SOLUTIONS
DETAIL 5
NTS
..
..
..,
L
.•
-......-:. ---:
BENCH WIDTH Q VARIES
.....-----=~ I(
4 FOOT MIN.
BENCH HEIGHT
>I
EXISTING GRADE ---/
. "" ---
----------
VER 1.0
TO~ SUITABLE BEARING MATERIAL
2% MIN. HEEL
~ WIDTH->I
CODE COMPLIANT KEYWAY
WITH MINIMUM DIMENSIONS:
TOE: 2 FOOT MIN.
HEEL: 3 FOOT MIN.
WIDTH: 15 FOOT MIN.
NOTES:
1. MAINTAIN MINIMUM 15 FOOT HORIZONTAL WIDTH
FROM FACE OF SLOPE TO BENCH/BACKCUT
2. SEE DETAIL 2 FOR DRAIN SPECIFICATIONS
SKIN FILL CONDITION DETAIL6
NTS
"' ADVANCED GEOTECHNICAL SOLUTIONS
..
....
"'
.. r r
H2 H1
........
........ ........ ........ ........
-..
UNSUITABLE
BEARING MATERIAL
(REMOVE) ---........ --
15 FOOT MIN.
. ..
. ;. ... .. .-----~
BENCH WIDTH
VARIES
I< >I
4 FOOT MIN .
BENCH HEIGHT
---I
---It"" ( W1 I
1 FOOT TILT BACK (MIN.)
i SUITABLE BEARING MATERIAL
'
-------------I ----./ < >I
W2
NOTES:
1. IF RECOMMENDED BY THE GEOTECHNICAL CONSULTANT,
THE REMAINING CUT PORTION OF THE SLOPE MAY REQUIRE
REMOVAL AND REPLACEMENT WITH AN ENGINEERED FILL
2. "W" SHALL BE EQUIPMENT WIDTH (15 FEET) FOR SLOPE HEIGHT
LESS THAN 25 FEET. FOR SLOPES GREATER THAN 25 FEET, "W" SHALL
BE DETERMINED BY THE GEOTECHNICAL CONSULTANT. AT NO
TIME SHALL "W" BE LESS THAN H/2
3. DRAINS WILL BE REQUIRED (SEE DETAIL 2)
VER 1.0
l}JAGS
ADVANCED GEOTECHNICAL SOLUTIONS
PARTIAL CUT SLOPE
STABILIZATION DETAIL 7
NTS
...
-----
DESIGN GRADE
5 FEET
MIN.
. ~,' ~~;
;
,'
--EXISTING GR~E ----
** SUBSURFACE
DRAINAGE
'
--
5 FEET
MIN.
', 7 . ',·7
'
SUITABLE BEARING MATERIAL REMOVE AND REPLACE
WITH ENGINEERED FILL
CUT LOT OVEREXCAVATION
DESIGN GRADE ..
ENGINEERED FILL .,...,,.._ .,...,,..._ . \\)-.\... , ' .,...,,.. ~~~ . ..
.,...,,.. . ~ . . . · · \~0 ~~ . · · , ' ** SUBSURFACE
_...A · x:-i:,,.~ N~r , ' DRAINAGE
5 FEET
MIN.
7 . '7
---
. -~~<o x-~o . .. .-----------------....,
· · ~.,,-<..'i>:-<o · r. · ' , ~ REQUIRED BENCH REMOVE AND REPLACE
0~SXJ · , ' WITH ENGINEERED FILL
SUITABLE BEARING MATERIAL
CUT-FILL LOT OVEREXCAVATION
NOTES:
* SEE REPORT FOR RECOMMENDED DEPTHS, DEEPER OVEREXCAVATION MAY BE REQUIRED BY
THE GEOTECHNICAL CONSULTANT BASED ON EXPOSED FIELD CONDITIONS
** CONSTRUCT EXCAVATION TO PROVIDE FOR POSITIVE DRAINAGE TOWARDS STREETS,
DEEPER FILL AREAS OR APPROVED DRAINAGE DEVICES BASED ON FIELD CONDITIONS
VER 1.0
CUT & CUT-FILL LOT
OVEREXCAVATION DETAIL 8
NTS
" ADVANCED GEOTECHNICAL SOLUTIONS
DESIGN GRADE
ADDITIONAL
ENGINEERED FILL
(TO DESIGN GRADE)
--EXISTING GRADE --- --7 ~ · . · ..
.,.
-----/ -----~ -- - ---//.
',,,,, ////. ..
TEMPORARY / ·
', ENGINEERED FILL //./ ',, (TO BE REMOVED) * //
ENGINEERED FILL ', 7. ..;,':-//
(EXISTING) , . 7 /. · · ',, //
//. ',, //. ..
UNSUITABLE
BEARING MATERIAL
. (REMOVE) . ·
',, // ---/ . . ---' / -------- -.1\/. - --. --. --- -
---.. -
*
VER 1.0
SUITABLE BEARING MATERIAL
REMOVE BEFORE PLACING ADDITIONAL ENGINEERED FILL
TYPICAL UP-CANYON PROFILE
REMOVAL ADJACENT TO
EXISTING FILL DETAIL 9
• ADVANCED GEOTECHNICAL SOLUTIONS
NTS
VER 1.0
DESIGN GRADE
CLEAR ZONE 10 FEET
4 FEET
0 t O< 15 FEET >'3
ENGINEERED FILL TYPICAL WINDROWS,
PLACED PARALLEL TO
SLOPE FACE
.......... ..... ..... .... .... .... .....
CLEAR ZONE DIMENSIONS FOR REFERENCE ONLY, ACTUAL DEPTH, WIDTH,
WINDROW LENGTH, ETC. TO BE BASED ON ELEVATIONS OF FOUNDATIONS,
UTILITIES OR OTHER STRUCTURES PER THE GEOTECHNICAL CONSULTANT OR
GOVERNING AGENCY APPROVAL
OVERSIZED MATERIAL DISPOSAL PROFILE
/fol~ ~t~?N°E~~~rg~~L~ :~~~~EN i}TI}J
1-:CTJ:-.1 WINDROWS 1·:W:.i
-..:.:_.:_·_·..:./ - - --/-- - -,·.:..._·_·_:./
HORIZONTALLY PLACED ENGINEERED FILL, FREE OF OVERSIZED MATERIALS AND
COMPACTED TO MINIMUM PROJECT STANDARDS
COMPACT ENGINEERED FILL ABOVE OVERSIZED MATERIALS TO FACILITATE
"TRENCH" CONDITION PRIOR TO FLOODING GRANULAR MATERIALS
WINDROW CROSS-SECTION
ENGINEERED FILL
r>o·.· ·.····••o::o·<o> >1
I~.<·.'.·.: .... ·.' ·:-: -~~---. ·>.': .... -<-:.; - ---~-~-~-~-~ ~-~-~-~-~~~ - -
GRANULAR MATERIALAPPROVED BY
THE GEOTECHNICAL CONSULTANT AND
CONSOLIDATED IN-PLACE BY FLOODING
WINDROW PROFILE
.... ....
NTS
OVERSIZED MATERIAL
DISPOSAL CRITERIA DETAIL 10
ADVANCED GEOTECHNICAL SOLUTIONS
VER 1.0
DESIGN GRADE
3/4-INCH PIPE COUPLING
3/4-INCH PIPE NIPPLE WELDED
TO SETTLEMENT PLATE
FOUND PLATE ON ONE-FOOT
COMPACTED SAND BEDDING
PROTECT IN-PLACE AT DESIGN GRADE
3-INCH SCHEDULE 40 PVC PIPE
----5-FOOT SECTIONS ATTACHED
WITH GLUED COUPLING JOINTS
EXTENSION ROD CONSISTING OF
5-FOOT SECTIONS OF 3/4-INCH
GALVANIZED PIPE, TOP AND
BOTTOM THREADED
SETTLEMENT PLATE,
2' x 2' x 1/4" STEEL
r--: ~---
2 r__ rn < <Ju. > 2 > <J SUITABLE BEARING MATERIAL
NOTES:
1. SETTLEMENT PLATE LOCATIONS SHALL BE SUFFICIENTLY IDENTIFIED BY THE
CONTRACTOR AND BE READILY VISIBLE TO EQUIPMENT OPERATORS.
2. CONTRACTOR SHALL MAINTAIN ADEQUATE HORIZONTAL CLEARANCE FOR EQUIPMENT
OPERATION AND SHALL BE RESPONSIBLE FOR REPAIRING ANY DAMAGE TO
SETTLEMENT PLATE DURING SITE CONSTRUCTION.
3. A MINIMUM 5-FOOT ZONE ADJACENT TO SETTLEMENT PLATE/EXTENSION RODS SHALL BE
ESTABLISHED FOR HAND-HELD MECHANICAL COMPACTION OF ENGINEERED FILL.
ENGINEERED FILL SHALL BE COMPACTED TO MINIMUM PROJECT STANDARD.
4. ELEVATIONS OF SETTLEMENT PLATE AND ALL EXTENSION ROD PLACEMENT SHALL BE
DOCUMENTED BY PROJECT CIVIL ENGINEER OR SURVEYOR.
NTS
aAGS SETTLEMENT PLATE DETAIL 11
ADVANCED GEOTECHNICAL SOLUTIONS
VER 1.0
SPRINKLER VAULT,
PLACED ABOVE GRADE
DESIGN GRADE PVC CAP
/ TO REDUCE SEDIMENT INFILL
NOTES:
3 FEET
MINIMUM
I I
~ PVCPIPE
REBAR OR
MIN. 6-INCH FLAT HEADED BOLT
WITH 2-INCH CLEARANCE AND
SURROUNDED WITH PVC PIPE
CONCRETE OR
----SLURRY BACKFILL
ENGINEERED FILL
1. SETTLEMENT MONUMENT LOCATIONS SHALL BE SUFFICIENTLY IDENTIFIED
AND BE READILY VISIBLE TO EQUIPMENT OPERATORS.
2. ELEVATIONS OF SURFACE MONUMENTS SHALL BE DOCUMENTED BY
PROJECT CIVIL ENGINEER OR SURVEYOR.
NTS
SETTLEMENT MONUMENT DETAIL 12
·" ADVANCED GEOTECHNICAL SOLUTIONS
-·
APPENDIXC
HOMEOWNER MAINTENANCE RECOMMENDATIONS
·•
...
...
I\OVI\NCED GEOTECHNICI\L SOLUTIONS, INC.
HOMEOWNER MAINTENANCE AND IMPROVEMENT CONSIDERATIONS
Homeowners are accustomed to maintaining their homes. They expect to paint their houses periodically,
replace wiring, clean out clogged plumbing, and repair roofs. Maintenance of the home site, particularly
on hillsides, should be considered on the same basis or even on a more serious basis because neglect can
result in serious consequences. In most cases, lot and site maintenance can be taken care of along with
landscaping, and can be carried out more economically than repair after neglect.
Most slope and hillside lot problems are associated with water. Uncontrolled water from a broken pipe,
cesspool, or wet weather causes most damage. Wet weather is the largest cause of slope problems,
particularly in California where rain is intermittent, but may be torrential. Therefore, drainage and erosion
control are the most important aspects of home site stability; these provisions must not be altered without
competent professional advice. Further, maintenance must be carried out to assure their continued
operation.
As geotechnical engineers concerned with the problems of building sites in hillside developments, we
offer the following list of recommended home protection measures as a guide to homeowners.
Expansive Soils
Some of the earth materials on site have been identified as being expansive in nature. As such, these
materials are susceptible to volume changes with variations in their moisture content. These soils will
swell upon the introduction of water and shrink upon drying. The forces associated with these volume
changes can have significant negative impacts (in the form of differential movement) on foundations,
walkways, patios, and other lot improvements. In recognition of this, the project developer has
constructed homes on these lots on post-tensioned or mat slabs with pier and grade beam foundation
systems, intended to help reduce the potential adverse effects of these expansive materials on the
residential structures within the project. Such foundation systems are not intended to offset the forces
(and associated movement) related to expansive soil, but are intended to help soften their effects on the
structures constructed thereon.
Homeowners purchasing property and living in an area containing expansive soils must assume a certain
degree of responsibility for homeowner improvements as well as for maintaining conditions around their
home. Provisions should be incorporated into the design and construction of homeowner improvements
to account for the expansive nature of the onsite soils material. Lot maintenance and landscaping should
also be conducted in consideration of the expansive soil characteristics. Of primary importance is
minimizing the moisture variation below all lot improvements. Such design, construction and
homeowner maintenance provisions should include:
•!• Employing contractors for homeowner improvements who design and build in recognition of
local building code and site specific soils conditions.
•!• Establishing and maintaining positive drainage away from all foundations, walkways, driveways,
patios, and other hardscape improvements.
•!• Avoiding the construction of planters adjacent to structural improvements. Alternatively, planter
sides/bottoms can be sealed with an impermeable membrane and drained away from the
improvements via subdrains into approved disposal areas.
•!• Sealing and maintaining construction/control joints within concrete slabs and walkways to reduce
the potential for moisture infiltration into the subgrade soils.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
_,,
·•
. ,,.
•!• Utilizing landscaping schemes with vegetation that requires minimal watering. Alternatively,
watering should be done in a uniform manner as equally as possible on all sides of the foundation,
keeping the soil "moist" but not allowing the soil to become saturated.
•!• Maintaining positive drainage away from structures and providing roof gutters on all structures
with downspouts installed to carry roof runoff directly into area drains or discharged well away
from the structures.
•!• A voiding the placement of trees closer to the proposed structures than a distance of one-half the
mature height of the tree.
•!• Observation of the soil conditions around the perimeter of the structure during extremely hot/dry
or unusually wet weather conditions so that modifications can be made in irrigation programs to
maintain relatively constant moisture conditions.
Sulfates
Homeowners should be cautioned against the import and use of certain fertilizers, soil amendments,
and/or other soils from offsite sources in the absence of specific information relating to their chemical
composition. Some fertilizers have been known to leach sulfate compounds into soils otherwise
containing "negligible" sulfate concentrations and increase the sulfate concentrations in near-surface soils
to "moderate" or "severe" levels. In some cases, concrete improvements constructed in soils containing
high levels of soluble sulfates may be affected by deterioration and loss of strength.
Water-Natural and Man Induced
Water in concert with the reaction of various natural and man-made elements, can cause detrimental
effects to your structure and surrounding property. Rain water and flowing water erodes and saturates the
ground and changes the engineering characteristics of the underlying earth materials upon saturation.
Excessive irrigation in concert with a rainy period is commonly associated with shallow slope failures and
deep seated landslides, saturation of near structure soils, local ponding of water, and transportation of
water soluble substances that are deleterious to building materials including concrete, steel, wood, and
stucco.
Water interacting with the near surface and subsurface soils can initiate several other potentially
detrimental phenomena other then slope stability issues. These may include expansion/contraction cycles,
liquefaction potential increase, hydro-collapse of soils, ground surface settlement, earth material
consolidation, and introduction of deleterious substances.
The homeowners should be made aware of the potential problems which may develop when drainage is
altered through construction of retaining walls, swimming pools, paved walkways and patios. Ponded
water, drainage over the slope face, leaking irrigation systems, over-watering or other conditions which
could lead to ground saturation must be avoided.
•!• Before the rainy season arrives, check and clear roof drains, gutters and down spouts of all
accumulated debris. Roof gutters are an important element in your arsenal against rain damage. If
you do not have roof gutters and down spouts, you may elect to install them. Roofs, with their,
wide, flat area can shed tremendous quantities of water. Without gutters or other adequate
drainage, water falling from the eaves collects against foundation and basement walls.
•!• Make sure to clear surface and terrace drainage ditches, and check them frequently during the
rainy season. This task is a community responsibility.
•!• Test all drainage ditches for functioning outlet drains. This should be tested with a hose and done
before the rainy season. All blockages should be removed.
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•:• Check all drains at top of slopes to be sure they are clear and that water will not overflow the
slope itself, causing erosion.
•:• Keep subsurface drain openings (weep-holes) clear of debris and other material which could
block them in a storm.
•:• Check for loose fill above and below your property if you live on a slope or terrace.
•:• Monitor hoses and sprinklers. During the rainy season, little, if any, irrigation is required.
Oversaturation of the ground is unnecessary, increases watering costs, and can cause subsurface
drainage.
•:• Watch for water backup of drains inside the house and toilets during the rainy season, as this may
indicate drain or sewer blockage.
•:• Never block terrace drains and brow ditches on slopes or at the tops of cut or fill slopes. These are
designed to carry away runoff to a place where it can be safely distributed.
•:• Maintain the ground surface upslope of lined ditches to ensure that surface water is collected in
the ditch and is not permitted to be trapped behind or under the lining.
•:• Do not permit water to collect or pond on your home site. Water gathering here will tend to either
seep into the ground (loosening or expanding fill or natural ground), or will overflow into the
slope and begin erosion. Once erosion is started, it is difficult to control and severe damage may
result rather quickly.
•:• Never connect roof drains, gutters, or down spouts to subsurface drains. Rather, arrange them so
that water either flows off your property in a specially designed pipe or flows out into a paved
driveway or street. The water then may be dissipated over a wide surface or, preferably, may be
carried away in a paved gutter or storm drain. Subdrains are constructed to take care of ordinary
subsurface water and cannot handle the overload from roofs during a heavy rain.
•:• Never permit water to spill over slopes, even where this may seem to be a good way to prevent
ponding. This tends to cause erosion and, in the case of fill slopes, can eat away carefully
designed and constructed sites.
•:• Do not cast loose soil or debris over slopes. Loose soil soaks up water more readily than
compacted fill. It is not compacted to the same strength as the slope itself and will tend to slide
when laden with water; this may even affect the soil beneath the loose soil. The sliding may clog
terrace drains below or may cause additional damage in weakening the slope. If you live below a
slope, try to be sure that loose fill is not dumped above your property.
•:• Never discharge water into subsurface blanket drains close to slopes. Trench drains are
sometimes used to get rid of excess water when other means of disposing of water are not readily
available. Overloading these drains saturates the ground and, if located close to slopes, may cause
slope failure in their vicinity.
•:• Do not discharge surface water into septic tanks or leaching fields. Not only are septic tanks
constructed for a different purpose, but they will tend, because of their construction, to naturally
accumulate additional water from the ground during a heavy rain. Overloading them artificially
during the rainy season is bad for the same reason as subsurface subdrains, and is doubly
dangerous since their overflow can pose a serious health hazard. In many areas, the use of septic
tanks should be discontinued as soon as sewers are made available.
•:• Practice responsible irrigation practices and do not over-irrigate slopes. Naturally, ground cover
of ice plant and other vegetation will require some moisture during the hot summer months, but
during the wet season, irrigation can cause ice plant and other heavy ground cover to pull loose.
This not only destroys the cover, but also starts serious erosion. In some areas, ice plant and other
heavy cover can cause surface sloughing when saturated due to the increase in weight and
weakening of the near-surface soil. Planted slopes should be planned where possible to acquire
sufficient moisture when it rains.
•:• Do not let water gather against foundations, retaining walls, and basement walls. These walls are
built to withstand the ordinary moisture in the ground and are, where necessary, accompanied by
subdrains to carry off the excess. If water is permitted to pond against them, it may seep through
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the wall, causing dampness and leakage inside the basement. Further, it may cause the foundation
to swell up, or the water pressure could cause structural damage to walls.
•!• Do not try to compact soil behind walls or in trenches by flooding with water. Not only is
flooding the least efficient way of compacting fine-grained soil, but it could damage the wall
foundation or saturate the subsoil.
•!• Never leave a hose and sprinkler running on or near a slope, particularly during the rainy season.
This will enhance ground saturation which may cause damage.
•!• Never block ditches which have been graded around your house or the lot pad. These shallow
ditches have been put there for the purpose of quickly removing water toward the driveway, street
or other positive outlet. By all means, do not let water become ponded above slopes by blocked
ditches.
•!• Seeding and planting of the slopes should be planned to achieve, as rapidly as possible, a well-
established and deep-rooted vegetal cover requiring minimal watering.
•!• It should be the responsibility of the landscape architect to provide such plants initially and of the
residents to maintain such planting. Alteration of such a planting scheme is at the resident's risk.
•!• The resident is responsible for proper irrigation and for maintenance and repair of properly
installed irrigation systems. Leaks should be fixed immediately. Residents must undertake a
program to eliminate burrowing animals. This must be an ongoing program in order to promote
slope stability. The burrowing animal control program should be conducted by a licensed
exterminator and/or landscape professional with expertise in hill side maintenance.
Geotechnical Review
Due to the fact that soil types may vary with depth, it is recommended that plans for the construction of
rear yard improvements (swimming pools, spas, barbecue pits, patios, etc.), be reviewed by a geotechnical
engineer who is familiar with local conditions and the current standard of practice in the vicinity of your
home.
In conclusion, your neighbor's slope, above or below your property, is as important to you as the slope
that is within your property lines. For this reason, it is desirable to develop a cooperative attitude
regarding hillside maintenance, and we recommend developing a "good neighbor" policy. Should
conditions develop off your property, which are undesirable from indications given above, necessary
action should be taken by you to insure that prompt remedial measures are taken. Landscaping of your
property is important to enhance slope and foundation stability and to prevent erosion of the near surface
soils. In addition, landscape improvements should provide for efficient drainage to a controlled discharge
location downhill of residential improvements and soil slopes.
Additionally, recommendations contained in the Geotechnical Engineering Study report apply to all
future residential site improvements, and we advise that you include consultation with a qualified
professional in planning, design, and construction of any improvements. Such improvements include
patios, swimming pools, decks, etc., as well as building structures and all changes in the site configuration
requiring earth cut or fill construction.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
APPENDIXD
PRELIMINARY STORM WATER INFILTRATION FEASIBILITY ANALYSIS
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APPENDIXB
GENERAL EARTHWORK SPECIFICATIONS
AND GRADING GUIDELINES
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
GENERAL EARTHWORK SPECIFICATIONS
I. General
A. General procedures and requirements for earthwork and grading are presented herein. The earthwork
and grading recommendations provided in the geotechnical report are considered part of these
specifications, and where the general specifications provided herein conflict with those provided in the
geotechnical report, the recommendations in the geotechnical report shall govern. Recommendations
provided herein and in the geotechnical report may need to be modified depending on the conditions
encountered during grading.
B. The contractor is responsible for the satisfactory completion of all earthwork in accordance with the
project plans, specifications, applicable building codes, and local governing agency requirements. Where
these requirements conflict, the stricter requirements shall govern.
C. It is the contractor's responsibility to read and understand the guidelines presented herein and in the
geotechnical report as well as the project plans and specifications. Information presented in the
geotechnical report is subject to verification during grading. The information presented on the exploration
logs depicts conditions at the particular time of excavation and at the location of the excavation.
Subsurface conditions present at other locations may differ, and the passage of time may result in
different subsurface conditions being encountered at the locations of the exploratory excavations. The
contractor shall perform an independent investigation and evaluate the nature of the surface and
subsurface conditions to be encountered and the procedures and equipment to be used in performing his
work.
D. The contractor shall have the responsibility to provide adequate equipment and procedures to
accomplish the earthwork in accordance with applicable requirements. When the quality of work is less
than that required, the Geotechnical Consultant may reject the work and may recommend that the
operations be suspended until the conditions are corrected.
E. Prior to the start of grading, a qualified Geotechnical Consultant should be employed to observe
grading procedures and provide testing of the fills for conformance with the project specifications,
approved grading plan, and guidelines presented herein. All remedial removals, clean-outs, removal
bottoms, keyways, and subdrain installations should be observed and documented by the Geotechnical
Consultant prior to placing fill. It is the contractor's responsibility to apprise the Geotechnical Consultant
of their schedules and notify the Geotechnical Consultant when those areas are ready for observation.
F. The contractor is responsible for providing a safe environment for the Geotechnical Consultant to
observe grading and conduct tests.
II. Site Preparation
A. Clearing and Grubbing: Excessive vegetation and other deleterious material shall be sufficiently
removed as required by the Geotechnical Consultant, and such materials shall be properly disposed of
offsite in a method acceptable to the owner and governing agencies. Where applicable, the contractor may
obtain permission from the Geotechnical Consultant, owner, and governing agencies to dispose of
vegetation and other deleterious materials in designated areas onsite.
B. Unsuitable Soils Removals: Earth materials that are deemed unsuitable for the support of fill shall be
removed as necessary to the satisfaction of the Geotechnical Consultant.
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C. Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks, wells,
pipelines, other utilities, or other structures located within the limits of grading shall be removed and/or
abandoned in accordance with the requirements of the governing agency and to the satisfaction of the
Geotechnical Consultant.
D. Preparation of Areas to Receive Fill: After removals are completed, the exposed surfaces shall be
scarified to a depth of approximately 8 inches, watered or dried, as needed, to achieve a generally uniform
moisture content that is at or near optimum moisture content. The scarified materials shall then be
compacted to the project requirements and tested as specified.
E. All areas receiving fill shall be observed and approved by the Geotechnical Consultant prior to the
placement of fill. A licensed surveyor shall provide survey control for determining elevations of
processed areas and keyways.
III. Placement of Fill
A. Suitability of fill materials: Any materials, derived onsite or imported, may be utilized as fill provided
that the materials have been determined to be suitable by the Geotechnical Consultant. Such materials
shall be essentially free of organic matter and other deleterious materials, and be of a gradation, expansion
potential, and/or strength that is acceptable to the Geotechnical Consultant. Fill materials shall be tested in
a laboratory approved by the Geotechnical Consultant, and import materials shall be tested and approved
prior to being imported.
B. Generally, different fill materials shall be thoroughly mixed to provide a relatively uniform blend of
materials and prevent abrupt changes in material type. Fill materials derived from benching should be
dispersed throughout the fill area instead of placing the materials within only an equipment-width from
the cut/fill contact.
C. Oversize Materials: Rocks greater than 8 inches in largest dimension shall be disposed of offsite or be
placed in accordance with the recommendations by the Geotechnical Consultant in the areas that are
designated as suitable for oversize rock placement. Rocks that are smaller than 8 inches in largest
dimension may be utilized in the fill provided that they are not nested and are their quantity and
distribution are acceptable to the Geotechnical Consultant.
D. The fill materials shall be placed in thin, horizontal layers such that, when compacted, shall not exceed
6 inches. Each layer shall be spread evenly and shall be thoroughly mixed to obtain near uniform moisture
content and uniform blend of materials.
E. Moisture Content: Fill materials shall be placed at or above the optimum moisture content or as
recommended by the geotechnical report. Where the moisture content of the engineered fill is less than
recommended, water shall be added, and the fill materials shall be blended so that near uniform moisture
content is achieved. If the moisture content is above the limits specified by the Geotechnical Consultant,
the fill materials shall be aerated by discing, blading, or other methods until the moisture content is
acceptable.
F. Each layer of fill shall be compacted to the project standards in accordance to the project specifications
and recommendations of the Geotechnical Consultant. Unless otherwise specified by the Geotechnical
Consultant, the fill shall be compacted to a minimum of 90 percent of the maximum dry density as
determined by ASTM Test Method: D1557-09.
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G. Benching: Where placing fill on a slope exceeding a ratio of 5 to 1 (horizontal to vertical), the ground
should be keyed or benched. The keyways and benches shall extend through all unsuitable materials into
suitable materials such as firm materials or sound bedrock or as recommended by the Geotechnical
Consultant. The minimum keyway width shall be 15 feet and extend into suitable materials, or as
recommended by the geotechnical report and approved by the Geotechnical Consultant. The minimum
keyway width for fill over cut slopes is also 15 feet, or as recommended by the geotechnical report and
approved by the Geotechnical Consultant. As a general rule, unless otherwise recommended by the
Geotechnical Consultant, the minimum width of the keyway shall be equal to 1/2 the height of the fill
slope.
H. Slope Face: The specified minimum relative compaction shall be maintained out to the finish face of
fill and stabilization fill slopes. Generally, this may be achieved by overbuilding the slope and cutting
back to the compacted core. The actual amount of overbuilding may vary as field conditions dictate.
Alternately, this may be achieved by back rolling the slope face with suitable equipment or other methods
that produce the designated result. Loose soil should not be allowed to build up on the slope face. If
present, loose soils shall be trimmed to expose the compacted slope face.
I. Slope Ratio: Unless otherwise approved by the Geotechnical Consultant and governing agencies,
permanent fill slopes shall be designed and constructed no steeper than 2 to 1 (horizontal to vertical).
J. Natural Ground and Cut Areas: Design grades that are in natural ground or in cuts should be evaluated
by the Geotechnical Consultant to determine whether scarification and processing of the ground and/or
overexcavation is needed.
K. Fill materials shall not be placed, spread, or compacted during unfavorable weather conditions. When
grading is interrupted by rain, filing operations shall not resume until the Geotechnical Consultant
approves the moisture and density of the previously placed compacted fill.
IV. Cut Slopes
A. The Geotechnical Consultant shall inspect all cut slopes, including fill over cut slopes, and shall be
notified by the contractor when cut slopes are started.
B. If adverse or potentially adverse conditions are encountered during grading; the Geotechnical
Consultant shall investigate, evaluate, and make recommendations to mitigate the adverse conditions.
C. Unless otherwise stated in the geotechnical report, cut slopes shall not be excavated higher or steeper
than the requirements of the local governing agencies. Short-term stability of the cut slopes and other
excavations is the contractor's responsibility.
V. Drainage
A. Back drains and Subdrains: Back drains and subdrains shall be provided in fill as recommended by the
Geotechnical Consultant and shall be constructed in accordance with the governing agency and/or
recommendations of the Geotechnical Consultant. The location of subdrains, especially outlets, shall be
surveyed and recorded by the Civil Engineer.
B. Top-of-slope Drainage: Positive drainage shall be established away from the top of slope. Site drainage
shall not be permitted to flow over the tops of slopes.
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C. Drainage terraces shall be constructed in compliance with the governing agency requirements and/or in
accordance with the recommendations of the Geotechnical Consultant.
D. Non-erodible interceptor swales shall be placed at the top of cut slopes that face the same direction as
the prevailing drainage.
VI. Erosion Control
A. All finish cut and fill slopes shall be protected from erosion and/or planted in accordance with the
project specifications and/or landscape architect's recommendations. Such measures to protect the slope
face shall be undertaken as soon as practical after completion of grading.
B. During construction, the contractor shall maintain proper drainage and prevent the ponding of water.
The contractor shall take remedial measures to prevent the erosion of graded areas until permanent
drainage and erosion control measures have been installed.
VII. Trench Excavation and Backfill
A. Safety: The contractor shall follow all OSHA requirements for safety of trench excavations. Knowing
and following these requirements is the contractor's responsibility. All trench excavations or open cuts in
excess of 5 feet in depth shall be shored or laid back. Trench excavations and open cuts exposing adverse
geologic conditions may require further evaluation by the Geotechnical Consultant. If a contractor fails to
provide safe access for compaction testing, backfill not tested due to safety concerns may be subject to
removal.
B. Bedding: Bedding materials shall be non-expansive and have a Sand Equivalent greater than 30.
Where permitted by the Geotechnical Consultant, the bedding materials can be densified by jetting.
C. Backfill: Jetting of backfill materials is generally not acceptable. Where permitted by the Geotechnical
Consultant, the bedding materials can be densified by jetting provided the backfill materials are granular,
free-draining and have a Sand Equivalent greater than 30.
VIII. Geotechnical Observation and Testing During Grading
A. Compaction Testing: Fill shall be tested by the Geotechnical Consultant for evaluation of general
compliance with the recommended compaction and moisture conditions. The tests shall be taken in the
compacted soils beneath the surface if the surficial materials are disturbed. The contractor shall assist the
Geotechnical Consultant by excavating suitable test pits for testing of compacted fill.
B. Where tests indicate that the density of a layer of fill is less than required, or the moisture content not
within specifications, the Geotechnical Consultant shall notify the contractor of the unsatisfactory
conditions of the fill. The portions of the fill that are not within specifications shall be reworked until the
required density and/or moisture content has been attained. No additional fill shall be placed until the last
lift of fill is tested and found to meet the project specifications and approved by the Geotechnical
Consultant.
C. If, in the opinion of the Geotechnical Consultant, unsatisfactory conditions, such as adverse weather,
excessive rock or deleterious materials being placed in the fill, insufficient equipment, excessive rate of
fill placement, results in a quality of work that is unacceptable, the consultant shall notify the contractor,
and the contractor shall rectify the conditions, and if necessary, stop work until conditions are
satisfactory.
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D. Frequency of Compaction Testing: The location and frequency of tests shall be at the Geotechnical
Consultant's discretion. Generally, compaction tests shall be taken at intervals not exceeding two feet in
fill height and 1,000 cubic yards of fill materials placed.
E. Compaction Test Locations: The Geotechnical Consultant shall document the approximate elevation
and horizontal coordinates of the compaction test locations. The contractor shall coordinate with the
surveyor to assure that sufficient grade stakes are established so that the Geotechnical Consultant can
determine the test locations. Alternately, the test locations can be surveyed and the results provided to the
Geotechnical Consultant.
F. Areas of fill that have not been observed or tested by the Geotechnical Consultant may have to be
removed and recompacted at the contractor's expense. The depth and extent of removals will be
determined by the Geotechnical Consultant.
G. Observation and testing by the Geotechnical Consultant shall be conducted during grading in order for
the Geotechnical Consultant to state that, in his opinion, grading has been completed in accordance with
the approved geotechnical report and project specifications.
H. Reporting of Test Results: After completion of grading operations, the Geotechnical Consultant shall
submit reports documenting their observations during construction and test results. These reports may be
subject to review by the local governing agencies.
ADVANCED GEOTECHNICAL SOLUTIONS, INC .
APPENDIXC
HOMEOWNER MAINTENANCE RECOMMENDATIONS
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HOMEOWNER MAINTENANCE AND IMPROVEMENT CONSIDERATIONS
Homeowners are accustomed to maintaining their homes. They expect to paint their houses periodically,
replace wiring, clean out clogged plumbing, and repair roofs. Maintenance of the home site, particularly
on hillsides, should be considered on the same basis or even on a more serious basis because neglect can
result in serious consequences. In most cases, lot and site maintenance can be taken care of along with
landscaping, and can be carried out more economically than repair after neglect.
Most slope and hillside lot problems are associated with water. Uncontrolled water from a broken pipe,
cesspool, or wet weather causes most damage. Wet weather is the largest cause of slope problems,
particularly in California where rain is intermittent, but may be torrential. Therefore, drainage and erosion
control are the most important aspects of home site stability; these provisions must not be altered without
competent professional advice. Further, maintenance must be carried out to assure their continued
operation.
As geotechnical engineers concerned with the problems of building sites in hillside developments, we
offer the following list of recommended home protection measures as a guide to homeowners.
Expansive Soils
Some of the earth materials on site have been identified as being expansive in nature. As such, these
materials are susceptible to volume changes with variations in their moisture content. These soils will
swell upon the introduction of water and shrink upon drying. The forces associated with these volume
changes can have significant negative impacts (in the form of differential movement) on foundations,
walkways, patios, and other lot improvements. In recognition of this, the project developer has
constructed homes on these lots on post-tensioned or mat slabs with pier and grade beam foundation
systems, intended to help reduce the potential adverse effects of these expansive materials on the
residential structures within the project. Such foundation systems are not intended to offset the forces
(and associated movement) related to expansive soil, but are intended to help soften their effects on the
structures constructed thereon.
Homeowners purchasing property and living in an area containing expansive soils must assume a certain
degree of responsibility for homeowner improvements as well as for maintaining conditions around their
home. Provisions should be incorporated into the design and construction of homeowner improvements
to account for the expansive nature of the onsite soils material. Lot maintenance and landscaping should
also be conducted in consideration of the expansive soil characteristics. Of primary importance is
minimizing the moisture variation below all lot improvements. Such design, construction and
homeowner maintenance provisions should include:
•!• Employing contractors for homeowner improvements who design and build in recognition of
local building code and site specific soils conditions.
•!• Establishing and maintaining positive drainage away from all foundations, walkways, driveways,
patios, and other hardscape improvements.
•!• Avoiding the construction of planters adjacent to structural improvements. Alternatively, planter
sides/bottoms can be sealed with an impermeable membrane and drained away from the
improvements via subdrains into approved disposal areas.
•!• Sealing and maintaining construction/control joints within concrete slabs and walkways to reduce
the potential for moisture infiltration into the subgrade soils.
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•!• Utilizing landscaping schemes with vegetation that requires minimal watering. Alternatively,
watering should be done in a uniform manner as equally as possible on all sides of the foundation,
keeping the soil "moist" but not allowing the soil to become saturated.
•!• Maintaining positive drainage away from structures and providing roof gutters on all structures
with downspouts installed to carry roof runoff directly into area drains or discharged well away
from the structures.
•!• A voiding the placement of trees closer to the proposed structures than a distance of one-half the
mature height of the tree.
•!• Observation of the soil conditions around the perimeter of the structure during extremely hot/dry
or unusually wet weather conditions so that modifications can be made in irrigation programs to
maintain relatively constant moisture conditions.
Sulfates
Homeowners should be cautioned against the import and use of certain fertilizers, soil amendments,
and/or other soils from offsite sources in the absence of specific information relating to their chemical
composition. Some fertilizers have been known to leach sulfate compounds into soils otherwise
containing "negligible" sulfate concentrations and increase the sulfate concentrations in near-surface soils
to "moderate" or "severe" levels. In some cases, concrete improvements constructed in soils containing
high levels of soluble sulfates may be affected by deterioration and loss of strength.
Water-Natural and Man Induced
Water in concert with the reaction of various natural and man-made elements, can cause detrimental
effects to your structure and surrounding property. Rain water and flowing water erodes and saturates the
ground and changes the engineering characteristics of the underlying earth materials upon saturation.
Excessive irrigation in concert with a rainy period is commonly associated with shallow slope failures and
deep seated landslides, saturation of near structure soils, local ponding of water, and transportation of
water soluble substances that are deleterious to building materials including concrete, steel, wood, and
stucco.
Water interacting with the near surface and subsurface soils can initiate several other potentially
detrimental phenomena other then slope stability issues. These may include expansion/contraction cycles,
liquefaction potential increase, hydro-collapse of soils, ground surface settlement, earth material
consolidation, and introduction of deleterious substances.
The homeowners should be made aware of the potential problems which may develop when drainage is
altered through construction of retaining walls, swimming pools, paved walkways and patios. Ponded
water, drainage over the slope face, leaking irrigation systems, over-watering or other conditions which
could lead to ground saturation must be avoided.
•!• Before the rainy season arrives, check and clear roof drains, gutters and down spouts of all
accumulated debris. Roof gutters are an important element in your arsenal against rain damage. If
you do not have roof gutters and down spouts, you may elect to install them. Roofs, with their,
wide, flat area can shed tremendous quantities of water. Without gutters or other adequate
drainage, water falling from the eaves collects against foundation and basement walls.
•!• Make sure to clear surface and terrace drainage ditches, and check them frequently during the
rainy season. This task is a community responsibility.
•!• Test all drainage ditches for functioning outlet drains. This should be tested with a hose and done
before the rainy season. All blockages should be removed.
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Check all drains at top of slopes to be sure they are clear and that water will not overflow the
slope itself, causing erosion.
Keep subsurface drain openings (weep-holes) clear of debris and other material which could
block them in a storm.
Check for loose fill above and below your property if you live on a slope or terrace.
Monitor hoses and sprinklers. During the rainy season, little, if any, irrigation is required.
Oversaturation of the ground is unnecessary, increases watering costs, and can cause subsurface
drainage.
Watch for water backup of drains inside the house and toilets during the rainy season, as this may
indicate drain or sewer blockage.
Never block terrace drains and brow ditches on slopes or at the tops of cut or fill slopes. These are
designed to carry away runoff to a place where it can be safely distributed.
Maintain the ground surface upslope of lined ditches to ensure that surface water is collected in
the ditch and is not permitted to be trapped behind or under the lining.
Do not permit water to collect or pond on your home site. Water gathering here will tend to either
seep into the ground (loosening or expanding fill or natural ground), or will overflow into the
slope and begin erosion. Once erosion is started, it is difficult to control and severe damage may
result rather quickly.
Never connect roof drains, gutters, or down spouts to subsurface drains. Rather, arrange them so
that water either flows off your property in a specially designed pipe or flows out into a paved
driveway or street. The water then may be dissipated over a wide surface or, preferably, may be
carried away in a paved gutter or storm drain. Subdrains are constructed to take care of ordinary
subsurface water and cannot handle the overload from roofs during a heavy rain.
•!• Never permit water to spill over slopes, even where this may seem to be a good way to prevent
ponding. This tends to cause erosion and, in the case of fill slopes, can eat away carefully
designed and constructed sites.
•!• Do not cast loose soil or debris over slopes. Loose soil soaks up water more readily than
compacted fill. It is not compacted to the same strength as the slope itself and will tend to slide
when laden with water; this may even affect the soil beneath the loose soil. The sliding may clog
terrace drains below or may cause additional damage in weakening the slope. If you live below a
slope, try to be sure that loose fill is not dumped above your property.
•:•
•!•
Never discharge water into subsurface blanket drains close to slopes. Trench drains are
sometimes used to get rid of excess water when other means of disposing of water are not readily
available. Overloading these drains saturates the ground and, if located close to slopes, may cause
slope failure in their vicinity.
Do not discharge surface water into septic tanks or leaching fields. Not only are septic tanks
constructed for a different purpose, but they will tend, because of their construction, to naturally
accumulate additional water from the ground during a heavy rain. Overloading them artificially
during the rainy season is bad for the same reason as subsurface subdrains, and is doubly
dangerous since their overflow can pose a serious health hazard. In many areas, the use of septic
tanks should be discontinued as soon as sewers are made available.
•!• Practice responsible irrigation practices and do not over-irrigate slopes. Naturally, ground cover
of ice plant and other vegetation will require some moisture during the hot summer months, but
during the wet season, irrigation can cause ice plant and other heavy ground cover to pull loose.
This not only destroys the cover, but also starts serious erosion. In some areas, ice plant and other
heavy cover can cause surface sloughing when saturated due to the increase in weight and
weakening of the near-surface soil. Planted slopes should be planned where possible to acquire
sufficient moisture when it rains.
•!• Do not let water gather against foundations, retaining walls, and basement walls. These walls are
built to withstand the ordinary moisture in the ground and are, where necessary, accompanied by
subdrains to carry off the excess. If water is permitted to pond against them, it may seep through
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
the wall, causing dampness and leakage inside the basement. Further, it may cause the foundation
to swell up, or the water pressure could cause structural damage to walls.
•!• Do not try to compact soil behind walls or in trenches by flooding with water. Not only is
flooding the least efficient way of compacting fine-grained soil, but it could damage the wall
foundation or saturate the subsoil.
•!• Never leave a hose and sprinkler running on or near a slope, particularly during the rainy season.
This will enhance ground saturation which may cause damage.
•!• Never block ditches which have been graded around your house or the lot pad. These shallow
ditches have been put there for the purpose of quickly removing water toward the driveway, street
or other positive outlet. By all means, do not let water become ponded above slopes by blocked
ditches.
•!• Seeding and planting of the slopes should be planned to achieve, as rapidly as possible, a well-
established and deep-rooted vegetal cover requiring minimal watering.
•!• It should be the responsibility of the landscape architect to provide such plants initially and of the
residents to maintain such planting. Alteration of such a planting scheme is at the resident's risk.
•!• The resident is responsible for proper irrigation and for maintenance and repair of properly
installed irrigation systems. Leaks should be fixed immediately. Residents must undertake a
program to eliminate burrowing animals. This must be an ongoing program in order to promote
slope stability. The burrowing animal control program should be conducted by a licensed
exterminator and/or landscape professional with expertise in hill side maintenance.
Geotechnical Review
Due to the fact that soil types may vary with depth, it is recommended that plans for the construction of
rear yard improvements (swimming pools, spas, barbecue pits, patios, etc.), be reviewed by a geotechnical
engineer who is familiar with local conditions and the current standard of practice in the vicinity of your
home.
In conclusion, your neighbor's slope, above or below your property, is as important to you as the slope
that is within your property lines. For this reason, it is desirable to develop a cooperative attitude
regarding hillside maintenance, and we recommend developing a "good neighbor" policy. Should
conditions develop off your property, which are undesirable from indications given above, necessary
action should be taken by you to insure that prompt remedial measures are taken. Landscaping of your
property is important to enhance slope and foundation stability and to prevent erosion of the near surface
soils. In addition, landscape improvements should provide for efficient drainage to a controlled discharge
location downhill of residential improvements and soil slopes.
Additionally, recommendations contained in the Geotechnical Engineering Study report apply to all
future residential site improvements, and we advise that you include consultation with a qualified
professional in planning, design, and construction of any improvements. Such improvements include
patios, swimming pools, decks, etc., as well as building structures and all changes in the site configuration
requiring earth cut or fill construction.
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
APPENDIXD
PRELIMINARY STORM WATER INFILTRATION FEASIBILITY ANALYSIS
·•
..
ADVANCED GEOTECHNICAL SOLUTIONS, INC.
·•
''"
APPENDIXD
INFILTRATION TESTING
1.0 TESTING METHODS AND PROCEDURES
To evaluate feasibility for infiltration onsite and to provide preliminary design infiltration rates, three (3)
borehole percolation tests were performed in general conformance with Appendix D, Section D.3.3.2 of
the recently adopted BMP Design Manual.
To provide representative continuous soiVgeologic logs for the percolation test holes, two of the
percolation test borings were located adjacent to exploratory soil borings that were logged and sampled as
part of our investigation (TB-1 and TB-2). A third boring (HS-3), utilizing the hollowstem auger rig, was
drilled and logged to a depth of approximately 6 feet from existing design grade in the approximate
location of the single family units (Parcel B). Based upon the lithology observed in the other borings HS-
I thru HS-4, TB-I & TB-2 the lithology was found to be relatively uniform with a minor increase in
depth of the geologic contact with the Santiago formation along north to northwestern portion of the
Home A venue portion of the project. Locations of the percolation test holes and the exploratory soil
borings are shown on Plate I, included herewith.
The percolation boreholes (P-1 and P-2) were excavated with a limited access tripod drill rig utilizing a 6-
inch diameter flight auger, and extended to depths of approximately "48" below ground surface.
Borehole HS-3 was excavated with a CME 75 truck-mounted hollowstem auger drill rig and extended
through topsoil or undocumented artificial fill, into Old Paralic Deposits. The Old Paralic Deposits can
generally be described as a fine-grained, light brown to light gray sand that is slightly moist to moist and
medium dense to dense. A third percolation hole utilized the geotechnical boring HS-3 in the northwest
corner of Parcel B. This percolation test is identified as HSP-3 and extended to a total depth of 72 inches
form exiting grade.
The resulting test holes were cleaned of loose debris, then filled with several gallons of clean, potable
water and allowed to pre-soak overnight. The following day the test holes were cleaned of sediment and
the bottom was lined with approximately 2-inches of washed gravel prior to percolation testing. A series
of falling head percolation tests were then performed. Test holes P-1 through P-3 were filled with clean,
potable water to a minimum of 20 inches above the bottom of the test hole and allowed to infiltrate. The
water levels was allowed to drop for a 30-minute period, the water level was then measured and the drop
rate calculated in inches per hour. Infiltration test borings P-1 and P-2 were dry after the 30 minute
period. Therefore, the sandy soil criteria was met and the time interval for those two test borings was
decreased to 10 minute intervals. The test holes were then refilled with water as necessary and the test
procedure was repeated over the course of approximately 6 hours for test borings HS-3 and until a
stabilized percolation rate was recorded for test borings P-1 and P-2.
The stabilized percolation rate was then converted to an infiltration rate based on the "Porchet Method"
utilizing the following equation:
\\''here:
I,=~ =AH60 r
At(xr2+2:rcrH,.11) At(r-+ 21·1 .. ,i)
I, = teste.d infiltration rate, inches/hour
Af-1 = change in head over the time interval, inches.
.::lt = time interval, minutes.
·r = effective radius oftest hole
H,.,.2 = average head over the time interval, inches
Logs of the field testing and graphical representations of the test data presented as infiltration versus time
interval are attached herewith as supporting documents for Worksheet C.4-1.
2.0 TEST RESULTS AND PRELIMINARY DESIGN VALUES
The results of our testing are summarized in Table 1 below.
TABLE 1
SUMMARY OF INFILTRATION/PERCOLATION TEST RESULTS
Approximate Tested Test Depth of Test
Hole No. Location Hole Test Elevation Geologic Unit Description Infiltration Rate
ft. above ms! (inches/hour)
P-1 800 Grand 48"(4') 62 msl Qop Medium to Fine-
grained Sand
P-2 800 Grand 48" (4') 61 msl Qop Medium to Fine-
grained Sand
HSP-3 Home Ave 72" (6') 57 msl Qop Medium to Fine-
grained Sand
In accordance with Appendix D, Section D.5 of the BMP Design Manual, a 'Factor of Safety' should be
applied to the tested infiltration rates to determine the design infiltration rates. The factor of safety is
determined by Worksheet D.5-1 and possesses a numerical value between 2 and 9. For the proposed
project site, the factor of safety worksheet yielded a Combined Factor of Safety (S,0,,1) of 3. However, for
the purposes of feasibility screening, it is recommended by San Diego County that a Factor of Safety of
2.0 be utilized. Table 2 below summarizes the design infiltration rates for the subject test holes utilizing a
factor of safety of 2.0.
TABLE2
SUMMARY OF DESIGN INFILTRATION RA TES
Test Hole No. Location Tested Infiltration Factor of Safety Design Infiltration
Rate (in /hr.) Rate (in./hr.)
P-1 800 Grand 2.0 2.0 1.0
P-2 800 Grand 2.83 2.0 1.42
HSP-3 Home Ave 0.77 2.0 0.39
AVERAGE RATE 0.93
2.00
2.83
0.77
3.0 DESIGN CONSIDERATIONS
3.1. Groundwater
The soil borings extended ten feet or greater below the bottom of the percolation test borings and
encountered groundwater/saturated soil as summarized in table 3.
TABLE3
SUMMARY OF DEPTH TO GROUNDWATER
Test Hole No. Location I Depth To Groundwater
P-1 800 Grand 14*
P-2 800 Grand 15*
HSP-3 Home Ave 16.5*
*-Extrapolated from adjacent boring
Based on our observations and experience with similar projects in the vicinity, the seasonal high
groundwater is anticipated to be approximately 14 feet below existing grade (approximate
elevation 48 msl).
3.2. Geotechnical Hazards
Slopes greater than 25% are not present onsite. Retaining walls and/or basement structures are
proposed on the partially subterranean 800 Grand portion of the site. Dependent on final design,
utility trenches (Parcel A & B) and basement walls (Parcel A) in proximity to BMP basins could
be subject to water intrusion. It is recommended that if infiltration is to be used it should only be
used on the Home A venue portion and should be located a minimum of 25 to 30 feet away from
the southerly edge of the Grand A venue structure.
3.3. Soil and Groundwater Contamination
During our recent site investigation, no soil contamination was observed, nor is any
contamination known to exist onsite. Groundwater was not encountered during out subsurface
investigations, and is not anticipated to be contaminated. Based on the State of California
Regional Water Quality Control Board (RWQCB) GeoTracker website, the closest site that had
environmental issues is located at 880 Carlsbad Village Drive, approximately 0.1 mile
southeasterly of the subject site. That site is listed as a leaking underground storage tank (LUST)
site that has a clean-up status as "completed", and the RWQCB case for that site is now closed.
3.4. Pretreatment prior to infiltration
At this time, it is not anticipated that stormwater will undergo pretreatment such as sedimentation
or filtration prior to infiltration.
3.5. Soil Characteristics
The infiltration surfaces are m Old Paralic Deposits. As encountered, these materials can
generally be described as medium to fine-grained sand with some silt, in a medium dense to
dense condition. This unit exhibited favorable characteristics for infiltration and appeared to be
relatively uniform, but somewhat denser with depth.
3.6. Proximity to water supply wells
No water supply wells are known to exist within 100 feet of the proposed basin.
4.0 CONCLUSIONS AND RECOMMENDATIONS
Based on the results of our preliminary infiltration testing, the onsite soils possess observed infiltration
rates ranging between 0.77 and 2.83 inches/hour. When utilizing a factor of safety of 2, preliminary
design infiltration rates range between 0.39 and 1.42 inches/hour, with an recommended average design
infiltration rate of 0.94 inches/hour. Based on the results of our site specific testing, infiltration rates for
the project site are above 0.50 inches/hour. For the Home A venue, single family residential portion of the
site it is our opinion that partial or full infiltration is feasible. For the southern portion of the project (800
Grand) which will consist of the partially subterranean condominium structure it is our opinion that
infiltration is not feasible due to the potential for water intrusion and for additional hydrostatic pressure
on the proposed subterranean garage. Accordingly infiltration on the 800 Grand portion of the site project
should not be considered.
ATTACHMENTS
STORM WATER STANDARDS BMPDESIGN MANUAL-WORKSHEET FORM C.4-1
SUPPORT DOCUMENTS AND FIELD DATA
Categorization ofinfiltration Feasibility Condition-800 Grand Worksheet C.4-1
Part 1 ~ fut1 Inftltt_atlon Feasibiluy Screeni,na: Cdtf!M'
Would infiltration of the full design volume be feasible from. a physical perspective without any undesirable
consequences that cannot be reasonably mitigated?
Criteria
1
Screening Question
Is the estimated reliable infiltration rate below proposed facility locations
greater than 0.5 inches per hour? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2 and Appendix D.
Provide basis:
Yes No
D
Two (2) borehole percolation tests were performed in proposed/possible BMP locations. Testing was performed
in general conformance with Appendix D, Section D.3.3.2 of the recently adopted BMP Design Manual. The
stabilized percolation rates were then converted to infiltration rates using the "Porch et Method". The observed
infiltration rates were calculated to be: 2.0 inches/hour in test hole P-land 2.83 inches/hour in test hole P-2. Using
a factor of safety of 2 for feasibility screening purposes yielded design infiltration rates of 1.00 in/hr and 1.42
in/hr. Inclusive of the additional infiltration test on the Home Ave (0.38in!hr) yields an average infiltration rate of
0.93 in/hr.
2
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The response
to this Screening Question shall be based on a comprehensive evaluation of
the factors presented in Appendix C.2.
Provide basis:
D
The average infiltration rates at this portion of the project site are greater than 0.5 inches/hour. However,
infiltration is not recommended due to the adverse affects the infiltration water may have on the subterranean
parking garage (increase in hydrostatic pressure, water proofing issues with the structure, and buoyancy issues
which could result in differential settlement).
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
Criteria
3
Worksheet C.4-1 Page 2 of 4-800 Grand
Screening Question
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of groundwater contamination (shallow water table, storm water
pollutants or other factors) that cannot be mitigated to an acceptable level?
The response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
Yes No
D
No known contamination exists at the site and the closest know site with contamination issues is located
approximately 0.1 miles southeast of the site.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
4
Can infiltration greater than 0.5 inches per hour be allowed without causing
potential water balance issues such as change of seasonality of ephemeral
streams or increased discharge of contaminated groundwater to surface
waters? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix C.3.
Provide basis:
D
The design infiltration rates at the project site are greater than 0.5 inches/hour. Infiltration at a rate greater than
0.5 inches/hour is not feasible for this project due to the subterranean component of the structure. As such, this
screening question does not control the feasibility of infiltration at the project site. Per Section C.4.4 of the BMP
Design Manual, final determination should be made by the project design engineer.
Part 1
Result*
If all answers to rows 1-4 are "Yes" a full infiltration design is potentially feasible.
The feasibility screening category is Full Infiltration
If any answer from row 1-4 is "No", infiltration may be possible to some extent but
would not generally be feasible or desirable to achieve a "full infiltration" design.
Proceed to Part 2
*To be completed using gathered site information and best professional judgment considering the definition of MEP
in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate findings
Worksheet C.4-1 Page 3 of 4-800 Grand
Part 2 -\>vtiaJ ·wm"*ti<w vs, NP lQfiltration feasibiJit,yScreeruna: Criteria
Would infiltration of water in any appreciable amount be physically feasible without any negative
consequences that cannot be reasonably mitigated?
Criteria
5
Screening Question
Do soil and geologic conditions allow for infiltration in any appreciable rate
or volume? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix C.2 and
Appendix D.
Provide basis:
Yes No
D
As discussed in our response to Criteria No. I, site specific infiltration testing yielded infiltration rates of greater
than 0.5 inches/hour. The sandy nature of the subsurface materials beneath the site, allow for infiltration in an
appreciable rate or volume. It is anticipated that over the lifetime of the development the infiltration rates will
further diminish. The BMP Design Manual utilizes the subjective terminology of 'appreciable' and fails to define
a lower bound infiltration rate. It is our current understanding that an 'appreciable' infiltration rate is interpreted
to be any perceptible amount of infiltration. Therefore, in consideration of the current interpretation, the soil and
geologic conditions at the project site allow for infiltration in an 'appreciable' rate or volume.
6
Can Infiltration in any appreciable quantity be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2.
Provide basis:
D
For the "Grand Avenue" Condominium structure supported by the proposed partially subterranean garage,
infiltration may create unwanted mounding and hydrostatic pressures on the buried portions of the structure.
Accordingly , it is our opinion that the condominium portion is not suitable for infiltration.
,,.
Criteria
7
Worksheet C.4-1 Page 4 of 4
Screening Question
Can Infiltration in any appreciable quantity be allowed without posing
significant risk for groundwater related concerns (shallow water table, storm
water pollutants or other factors)? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendix C.3.
Provide basis:
Yes No
D
The proposed basin location has adequate separation (10 feet) to seasonal high groundwater. There are no known
water supply wells within 100 feet of the project site. According to the State Water Board's Geotracker website,
the closest site with contamination issues is located 0. I miles from the site. That site is reported as a LUST
cleanup, and the case has been closed. Land use in the project vicinity is predominantly multi-family residential
with locally interspersed commercial/retail. There are no known contamination risks from current land use
activities. As such, we do not anticipate that construction of the proposed BMP basin will adversely impact
receiving channels in the project vicinity.
8
Can infiltration be allowed without violating downstream water rights? The
response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
D
The project site is graded and is located in a developed neighborhood with impermeable surfaces where surface
waters are controlled and directed to storm drain inlets. There is no apparent evidence that construction of BMP
basins would divert or otherwise preclude flow to downstream water bodies. Per Section C.4.4 of the BMP
Design Manual, final determination should be made by the project design engineer.
Part 2
Result*
If all answers from row 5-8 are "Yes", then partial infiltration design is potentially
feasible. The feasibility screening category is Partial Infiltration.
If any answer from row 5-8 is "No", then infiltration of any volume is considered to be
infeasible within the drainage area. The feasibility screening category is No Infiltration.
*To be completed using gathered site information and best professional judgment considering the definition of
MEP in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate
findings
Categorization of Infiltration Feasibility Condition-Home Ave Worksheet C.4-1
Part 1 • Full Iufllttation Feasibility Sc,t;eening Criteria
Would infiltration of the full design volume be feasible from a physical perspective with<mt any undesirable
consequences that cannot be reasonably mitigated?
Criteria
1
Screening Question
Is the estimated reliable infiltration rate below proposed facility locations
greater than 0.5 inches per hour? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendix C.2 and Appendix D.
Provide basis:
Yes No
D
One (I) borehole percolation tests was performed in proposed/possible BMP location. One was conducted for
Home Ave single family detached (HS-3); and two were conducted for the 800 Grand condominium portion Pl
and P2. Testing was performed in general conformance with Appendix D, Section D.3.3.2 of the recently adopted
BMP Design Manual. The stabilized percolation rates were then converted to infiltration rates using the "Porchet
Method". The observed infiltration rates were calculated to be 0.77 inches/hour in test hole HSP-3 (Home Ave)
and 2.0 inches/hour in test hole P-land 2.83 inches/hour in test hole P-2 on the Grand Ave. portion. Using a factor
of safety of 2 for feasibility screening purposes yielded design infiltration rates of 0.39(Home Ave). Using a
factor of safety of 2 for feasibility screening purposes yielded design infiltration rates of 1.00 in/hr and 1.42 in/hr.
and 0.38in/hr. It is our opinion that an average infiltration rate of 0.93 in/hr should be used for both sites given the
similar soils and geology.
2
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The response
to this Screening Question shall be based on a comprehensive evaluation of
the factors presented in Appendix C.2.
Provide basis:
D
Yes an infiltration rate of 0.93in/hr can be used for the design of possible infiltration on the Home Avenue
portion of the project. This opinion is based upon: the similarity of the soils exposed in the 3 percolation
test borings; the lower rate found in HS-1 is likely related to the near surface compaction as a result of the
original parking lot and drive isle construction activities. The types of soils and the blow counts within the
upper soils are relatively uniform. Accordingly, once the proposed infiltration section is cut to the design
grade (18 to 24 inches) it is conservatively estimated that the average rate presented herein can be utilized for
design.
Based upon the proposed location in the drive aisles/parking areas it is not anticipated that this will
adversely affect the proposed improvements provided the building slabs are adequately waterproofed with a
suitable moisture barrier and the buried utility lines are located outside of the pervious pavement or
adequately backfilled with a sand cement slurry where they intercept the permeable pavement.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability.
..
...
Criteria
3
Worksheet C.4-1 Page 2 of 4-Home Ave.
Screening Question
Can infiltration greater than 0.5 inches per hour be allowed without increasing
risk of groundwater contamination (shallow water table, storm water
pollutants or other factors) that cannot be mitigated to an acceptable level?
The response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
Yes No
D
No known contamination exists at the site and the closest know site with contamination issues is located
approximately 0.1 miles southeast of the site.
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide
narrative discussion of study/ data source applicability .
4
Can infiltration greater than 0.5 inches per hour be allowed without causing
potential water balance issues such as change of seasonality of ephemeral
streams or increased discharge of contaminated groundwater to surface
waters? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix C.3.
Provide basis:
D
The design infiltration rates at the Home Ave portion of the project are suitable provided they do not infiltrate
into the buried utilities and that they are a minimum of 25 to 30 feet horizontally away from the Grand Ave
podium structure and drain in a south to north direction. Per Section C.4.4 of the BMP Design Manual. final
determination should be made by the project design engineer.
Part 1
Result*
If all answers to rows 1-4 are "Yes" a full infiltration design is potentially feasible.
The feasibility screening category is Full Infiltration
If any answer from row 1-4 is "No", infiltration may be possible to some extent but
would not generally be feasible or desirable to achieve a "full infiltration" design.
Proceed to Part 2
*To be completed using gathered site information and best professional judgment considering the definition of MEP
in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate findings
Worksheet C.4-1 Page 3 of 4-Home Ave
Part 2-Pattlal Infiltration vs. No Infilttation Fe@Slbilhy Screening Criteria
Would infiltration of water in any appreciable amount be physically feasible without any negative
consequences that cannot be reasonably mitigated?
Criteria
5
Screening Question
Do soil and geologic conditions allow for infiltration in any appreciable rate
or volume? The response to this Screening Question shall be based on a
comprehensive evaluation of the factors presented in Appendix C.2 and
Appendix D.
Provide basis:
Yes No
D
Site specific infiltration testing yielded infiltration rates of greater than 0.5 inches/hour. The sandy nature of the
subsurface materials beneath the site, allow for infiltration in an appreciable rate or volume. It is anticipated that
over the lifetime of the development the infiltration rates will further diminish. The BMP Design Manual utilizes
the subjective terminology of 'appreciable' and fails to define a lower bound infiltration rate. It is our current
understanding that an 'appreciable' infiltration rate is interpreted to be any perceptible amount of infiltration.
Therefore, in consideration of the current interpretation, the soil and geologic conditions at the project site allow
for infiltration in an 'appreciable' rate or volume.
6
Can Infiltration in any appreciable quantity be allowed without increasing
risk of geotechnical hazards (slope stability, groundwater mounding, utilities,
or other factors) that cannot be mitigated to an acceptable level? The
response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.2.
Provide basis:
D
Partial Infiltration can be allowed in the proposed BMP basin/Permeable pavement locations without
significantly increasing the risk of geotechnical hazards provided appropriate mitigation/remedial grading
measures are performed during site development/basin construction. The infiltration surface for the proposed
BMPs have not been finalized at this time, however, it is expected that they will be within the native material at
the site (Old Paralic Deposits) As encountered, the Old Paralic Deposits beneath the site, consist predominantly
of sand and silty sand, in a dense to very dense condition. Some gravely sand was observed at the bottom of the
Old Paralic Deposits. Below the Old Paralic Deposits, a less permeable silty claystone was encountered and
assigned to the Santiago Formation. More detailed recommendations should be provided when final design
plans become available. For the "Home" Avenue portion of the development it is our opinion that infiltration
within the proposed driveways and parking lots is suitable.
Criteria
7
Worksheet C.4-1 Page 4 of 4 Home Ave
Screening Question
Can Infiltration in any appreciable quantity be allowed without posing
significant risk for groundwater related concerns (shallow water table, storm
water pollutants or other factors)? The response to this Screening Question
shall be based on a comprehensive evaluation of the factors presented in
Appendix C.3.
Provide basis:
Yes No
D
The proposed basin location has adequate separation (> 10 feet) to seasonal high groundwater. There are no
known water supply wells within 100 feet of the project site. According to the State Water Board's Geotracker
website, the closest site with contamination issues is located 0.1 miles from the site. That site is reported as a
LUST cleanup, and the case has been closed. Land use in the project vicinity is predominantly multi-family
residential with locally interspersed commercial/retail. There are no known contamination risks from current land
use activities. As such, we do not anticipate that construction of the proposed BMP basin will adversely impact
receiving channels in the project vicinity.
8
Can infiltration be allowed without violating downstream water rights? The
response to this Screening Question shall be based on a comprehensive
evaluation of the factors presented in Appendix C.3.
Provide basis:
D
The project site is graded and is located in a developed neighborhood with impermeable surfaces where surface
waters are controlled and directed to storm drain inlets. There is no apparent evidence that construction of BMP
basins would divert or otherwise preclude flow to downstream water bodies. Per Section C.4.4 of the BMP
Design Manual, final determination should be made by the project design engineer.
Part 2
Result*
If all answers from row 5-8 are "Yes", then partial infiltration design is potentially
feasible. The feasibility screening category is Partial Infiltration.
If any answer from row 5-8 is "No", then infiltration of any volume is considered to be
infeasible within the drainage area. The feasibility screening category is No Infiltration.
*To be completed using gathered site information and best professional judgment considering the definition of
MEP in the MS4 Permit. Additional testing and/or studies may be required by the City Engineer to substantiate
findings
• .. ..
PERQOLATJON TESTDATASHEET
Project: 800 Grand Carlsbad Project No: 1607-03 Date: 9/10/2016
Test Hole No: P-1 Tested By: FE Water Temp. 64°
~~~~~~~~~~------
Depth of Test Hole: 48 inches USC S: Qop AirTemp 62°
Test Hole Dimensions (Inches)
Length 48 Width Diameter 6 Avg. Water Column 21
Infiltration Test
Trial No. Start Time Stop Time Time Interval (Pieziometric Surface in inches) Pere Rate Infiltration Rate* Notes
(hr and min) (hr and min) (min.) Start Depth End Depth Depth Change (in./hr.) (in./hr.)
1 9:35 9:45 30 23.88 48.00 Dry DRY 4.00 DRY
2 9:48 10:18 10 23.50 33.00 9.50 57.00 3.80
3 10:20 10:50 10 24.25 33.50 9.25 55.50 3.70
4 10:51 11 :21 10 24.75 33.88 9.13 54.78 3.65
5 11:22 11 :52 10 23.25 32.00 8.75 52.50 3.50
6 11 :53 12:23 10 24.25 31.25 7.00 42.00 2.80
7 12:24 12:54 10 24.00 29.75 5.75 34.50 2.30
8 12:55 13:25 10 23.25 29.00 5.75 34.50 2.30
9 13:26 13:56 10 24.25 29.75 5.50 33.00 2.20
10 13:58 14:18 10 23.88 29.00 5.12 30.72 2.05
11 14:19 14:49 10 24.88 30.10 5.22 31.32 2.09
12 14:51 15:01 10 24.25 29.38 5.13 30.78 2.05
*Calculated via Porchet Method
.. ~ ~
800 Grand -Test Hole P-1
5.00
4.50
4.00
3.50
~ 3.00
C
w' .....,
ro er: 2.50 C 0
+-' ~
== .;::: 2.00 C
1.50
1.00
0.50 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -·
0.00
0 30 60 90 120 150 180 210 240 270 300
Time Elapsed (min)
•• i ., "'
PERCOLATIC PERCOLATION DATA St:IEET
Project: 800 Grand Carlsbad Project No: 1607-03 Date: 9/10/2016
Test Hole No: P-2 Tested By: FE Water Temp. 64° -----
Depth of Test Hole: 48 USCS : Qop Air Temp 62°
Test Hole Dimensions (Inches)
Length 48 Width Diameter 6 Avg. Water Column 20
Infiltration Test
Trial No. Start Time Stop Time Time Interval (Pieziometric Surface in inches) Pere Rate Infiltration Rate* Notes
(hr and min) (hr and min) (min.) Start Depth End Depth Depth Change (in./hr.) (in./hr.)
1 9:35 10:05 10 23.88 34.00 10.12 60.72 4.24
2 10:07 10:37 10 23.50 33.70 10.20 61.20 4.27
3 10:38 11:08 10 24.25 33.50 9.25 55.50 3.87
4 11:09 11 :39 10 24.75 33.88 9.13 54.78 3.82
5 11 :45 12: 15 10 23.25 32.00 8.75 52.50 3.66
6 12:20 12:50 10 24.25 31.25 7.00 42.00 2.93
7 12:53 13:23 10 24.00 30.75 6.75 40.50 2.83
8 13:26 13:56 10 23.25 30.30 7.05 42.30 2.95
9 13:58 14:28 10 24.25 31.00 6.75 40.50 2.83
10 14:30 15:00 10 23.88 30.50 6.62 39.72 2.77
11 15:04 15:34 10 24.88 31.75 6.87 41.22 2.88
12 15:37 16:07 10 24.25 31.00 6.75 40.50 2.83
13
14
15
*Calculated via Porchet Method
800 Grand-Test Hole P-2
5.00
4.50
4.00
3.50
l:: 3.00 ........ ~
a.,' ..... ro ~ 2.50
0 -;:;
~ .:!::'.
'§ 2.00
1.50
1.00
0.50 - - - - - - - - - -------------------------------------------------.
0.00
0 30 60 90 120 150 180 210 240 270 300
Time Elapsed (min)
PERCOLATION DATA SHEET
Project: 800 Grand Carlsbad
Test Hole No: HSP-3
Project No:
_Tested By:
12 uses: Depth of Test Hole:
Test Hole Dimensions (Inches)
Length 72 Width
Infiltration Test
Trial No. Start Time Stop Time Time Interval
(hr and min) (hr and min) (min.)
1 9:00 9:30 30
2 9:37 10:07 30
3 10:10 10:40 30
4 10:45 11: 15 30
5 11: 17 11 :47 30
6 11:50 12:20 30
7 12:23 12:53 30
8 12:55 13:25 30
9 13:26 13:56 30
10 14:00 14:30 30
11 16:03 16:33 30
*Calculated via Porchet Method
ii lo-
1607-03 Date: 9/10/2016
JC Water Temp. 64° -----
Qop AirTemp 62°
Diameter 8 Avg. Water Column 43 -------
(Pieziometric Surface in inches) Pere Rate Infiltration Rate* Notes
Start Depth End Depth Depth Change (in./hr.) (in./hr.)
24.00 33.25 9.25 18.50 0.82
23.50 33.40 9.90 19.80 0.88
24.25 34.00 9.75 19.50 0.87
24.75 34.25 9.50 19.00 0.84
23.25 32.88 9.63 19.26 0.86
24.25 33.25 9.00 18.00 0.80
24.00 33.00 9.00 18.00 0.80
23.25 32.00 8.75 17.50 0.78
24.25 32.75 8.50 17.00 0.76
23.88 32.50 8.62 17.24 0.77
24.25 32.88 8.63 17.26 0.77
" • ;.
800 Grand-Test Hole P-3
5.00
4.50
4.00
3.50
'-~ 3.00
!:::
2::' ro 0:: C 2.50
0 ·;:;
~ ±:: '§ 2.00
1.50
1.00
O.~ ----------------------------------------------------------
0.00
0 30 60 90 120 150 180 210 240 270 300
Time Elapsed (min)
2~· V 10'
-·
r~' . -( .\.J ~----------""---, \\ {i7~;!
Hs-1 h ~..,, \,,~ 0-0.5' afu _ -"'
' "' 0.5-19' Qop , "v1,
19-20' Tsa· 1
----. ' ! ,~;-··
@ 16.5' S~t(t~CJ
TD=20' (Z
.. :)\
;-----------
HS-3&HSP:-3\
o· 20· 40' ~~-----SCALE: 1" = 20'
0-0.5' afu (
0.5-6' Qoe
TD=6' 1'-· , .... f: /
60'
r·
;(
: l
~ !
i
c· ·,
-. ;.::r-
A1
I '
-· ... ;.
,,,·~ . · ..
HOPE AVE
--
---
•. , ::_. ____ ··-······ I
.·.·--
_.:,.._.
. -",,
•:· ""'-'·'--'--· -------/."
,-
Q..:0:5'afu
, ,.r,:_'.:5_1's' ',Qe.._p--_ ·: -r::.:-:: V o.
18-20' Tsa __ _
@ 15''SatGrated
TD=20'
------+~~/-_,
HS-2-.
'.;
·.,
\-
Os0.4' iatu->'
0 .4-20'(Qop I
'(-\ '.j
... /
'/
----------
----------------------"-""" . --. ---·. .. ·' :"-·:: '"',""""".''"·"""
-------"·-.. ·---------____ ,, ___ .. ,, ·-----------
I e-...,._ ______ _
! r u '
20-21 :5! Tsa "·----., .. -· ________ _ __ _ _____ , ___ ,_:.·· .c..--------·
@ 1 atr Sf!t u f:,-a 1 _~:1,J.,,,, __ ,,.,__,,.,_.,,,_ ,"")""---°"---.,,, ______ ""'-=;t:t;;,: __ ---~--------~---;::-__ :;;; __ :':::__=; ___ -2':::;~_,;;:_±-:::_ ::: __ ~=---=--::;;:z=-----;-__ -:-::_ .. :;::, __ -:-:: __ -:-::_ =:i:::-====-;c_=_--;-_ =_ ==~,
TD=21.5'
_.,;;-
\ I 'I I I \ I
I I ' ,' ! J ' J I ' \I ' I V (
---· 1 I
:
/ ·-1. •., .. -_
' '
S,
I , ,
rH I , >C""-f<..::· u . I '\ -~~,
/
Qlf:
f 1L. lli f J --· . l . -
.---':ti.U .
=···=
---c:; .. .
I ' !
-""J
D
-' ;.,
./ /"'
----=-=------------s I
--1 1· jl=
\-~C----JI
=
~OP
=
J
I
_,., J -J "
I
----·----
' V • ' • --
,_-._-_,1_:''" : . --.
' :
A'
:~,. '
/ ! \_
TB-1
0-1' afu
1-16' Qop
@ 14' Saturated
-TQ=t6' ' ,_,
!i
I l
/
! j
!•
·r11,._
-· _;,.-···<
-~. _,·-·-.. , ..
TB-2
0-0.5' afu
o.5-11· Oop
TD=1;L'
.
,,·, . '
_lL_-
-'
Project#
LEGEND:
afu Undocumented Fill
Qop Old Paralic Deposits
Tsa Santiago Formation
Hollowstem Auger Boring
TB-2 E9 Tri Pod Auger Boring
P-1 • Percolation Boring
A A'
I I Cross Section Location
PLATE 1
GS ADV/1.NCED GEOTECHNICA.l SOLUTIONS, INC.
485 Corporate Drive, Suite B
Escondido, California 92029 ·
Telephone: (714) 786-5661 Fax: (714) 409-3287
Date: P/W 1607-03
Report#
1607-03-8-2 October 2016
bliA,lnc. -
land pbnning, cMI englnoo!ling, iurveylng
5115 AVENIDA ENCINAS
SUITE "L""
CARLSBAD, CA. 92008-4387
(760) 931-8700
----- ----------
SHEET20F3
A
700
680
---. I-
LL.. ---z:
0 660 I-<( > w
_J HS-3 w
640 --?--
Tsa
620
B
700 -
---. I-Li.. 680 ----
z:
0
I-
<( > w 660 _J -
w
r::
UTB-:._2
------640
Qop Qop
-?-- - - - - -__. ------
-
afu
0.5ft
I
'
Qop_ --?----
Tsa
Tsa HS-4
Ramp Down
.
--------- --?---
CROSS SECTIONS A-A', AND B-B'
SCALE H&V 1 "=20'
Proposed 3-Story Structure
Qop
--?-
Proposed 3 Story Structure
Proposed
Basement
..
Qop -? -------
Tsa
A'
700
680
--... I-Li.. ---z:
660 0
I-<( > w
_J w
TB-2
-·--? 640
Tsa
620
B'
-700
,..-....,
I-
680 LL.. ----
z:
0
.· I-
<( > 660 w
_J w
PL -
640 TB-1 ----~
LEGEND:
Existing Grade
-..........._ --Assumed ( +6") Finish Grade
Project#
P/W 1607-03
PLATE2
I\D\IANCEIJ GEOTECHNICIU.. SOLUTIONS, INC
485 Corporate Drive, Suite B
Escondido. California 92029
Telephone: (714) 786-5661 Fax: (714) 409-3287
Date:
October 201 6