HomeMy WebLinkAboutPD 2023-0016; KINOVATE PRODUCTION FACILITY TI; GEOTECHNICAL REPORT; 2022-09-18THESE PLANS/DOCUMENTS HAVE BEENREVIEWED FOR COMPLIANCE WITH THEAPPLICABLE CALIFORNIA BUILDING STANDARDSCODES AS ADOPTED BY THE STATE OFCALIFORNIA AND AMENDED BY THEJURISDICTION. PLAN REVIEW ACCEPTANCE OFDOCUMENTS DOES NOT AUTHORIZECONSTRUCTION TO PROCEED IN VIOLATION OFANY FEDERAL, STATE, NOR LOCAL REGULATION.
BY: _________________ DATE: ________________
True North Compliance Services, Inc.
THIS SET OF THE PLANS AND SPECIFICATIONSMUST BE KEPT ON THE JOB SITE AT ALL TIMESAND IT IS UNLAWFUL TO MAKE ANY CHANGES ORALTERATIONS WITHOUT PERMISSION FROM THECITY. OCCUPANCY OF STRUCTURE(S) IS NOTPERMITTED UNTIL FINAL APPROVAL IS GRANTEDBY ALL APPLICABLE DEPARTMENTS.
Areli Sanchez 2/2/2024
PARTNER
GEOTECHNICAL REPORT
Kinovate Production Faci lity Tl
1935 Camino Vida Roble
Carlsbad, California 92008
September 18, 2022
Partner Project Number: 21 -337276.5
Plan ID: PD2023-0016
Permit ID: GR2023-0026
Prepared for:
Nitto Denko Technical Corp
50 1 Via Del Monte
Oceanside, California 92058
Engineers who understand your business
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 3
2.3 References
The following references were used to generate this report:
California Geological Survey (CGS), Note 36, California Geomorphic Provinces, 2002.
California State Water Resource Control Board (SWRCB), GeoTracker tool, accessed 8/1/2022
Federal Emergency Management Agency, FEMA Flood Map Service Center, accessed 8/1/2022
Google Earth Pro (Online), accessed 8/1/2022
Historic Aerials by NETR Online, accessed 8/1/2022
National Geologic Map Database, Miller, F.K., and Cossette, P.M., 2004, Preliminary geologic map of the Big
Bear City 7.5' quadrangle, San Bernardino County, California, U.S. Geological Survey; Open-File Report OF-
2004-1193, scale 1:24,000
Partner Engineering and Science, Inc.,
OSHPD Seismic Design Maps, accessed online 8/1/2022
United States Department of Agriculture, Web Soil Survey, accessed online 8/1/2022
United States Geological Survey, California Interactive Geologic Map accessed 8/1/2022
United States Geological Survey, Lower 48 States 2014 Seismic Hazard Map, accessed online 8/1/2022
United States Geologic Survey, Earthquake Hazards Program (Online), accessed 8/1/2022
2.4 Limitations
The conclusions, recommendations, and opinions in this report are based upon soil samples and data
obtained in widely spaced locations that were accessible at the time of exploration and collected based on
project information available at that time. Our findings are subject to field confirmation that the samples
we obtained were representative of site conditions. If conditions on the site are different than what was
encountered in our borings, the report recommendations should be reviewed by our office, and new
recommendations should be provided based on the new information and possible additional exploration if
needed. It should be noted that geotechnical subsurface evaluations are not capable of predicting all
subsurface conditions, and that our evaluation was performed to industry standards at the time of the study,
no other warranty or guarantee is made.
Likewise, our document review and geologic research study made a good-faith effort to review readily
available documents that we could access and were aware of at the time, as listed in this letter. We are not
able to guarantee that we have discovered, observed, and reviewed all relevant site documents and
conditions. If new documents or studies are available following the completion of the report, the
recommendations herein should be reviewed by our office, and new recommendations should be provided
based on the new information and possible additional exploration if needed.
This report is intended for the use of the client in its entirety for the proposed project as described in the
text. Information from this report is not to be used for other projects or for other sites. All of the report
must be reviewed and applied to the project or else the report recommendations may no longer apply. If
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 4
pertinent changes are made in the project plans or conditions are encountered during construction that
appear to be different than indicated by this report, please contact this office for review. Significant
variations may necessitate a re-evaluation of the recommendations presented in this report. The findings in
this report are valid for one year from the date of the report. This report has been completed under specific
Terms and Conditions relating to scope, relying parties, limitations of liability, indemnification, dispute
resolution, and other factors relevant to any reliance on this report.
If a building permit is obtained for the project based on the submittal of this report, it would become the
design geotechnical report for the project. If parties other than Partner are engaged to provide construction
geotechnical special inspection services, they will also be required to assume construction geotechnical
engineer of record (GEOR) services as well. To confirm this, they should issue a letter concurring with the
findings and recommendations in this geotechnical design report or providing alternate recommendations
prior to the start of construction. The GEOR should be directly involved in the construction process, provide
engineering review the special inspection reports on a daily basis, and sign off at the end of the project that
the construction was done per the geotechnical design report. If Partner is not the GEOR, we should be
contacted as the design geotechnical engineer in the case of changed conditions or changes to the planned
construction. Interpretation of the design geotechnical report during construction, response to project RFI’s,
and oversight of special inspectors and quality control testing is to be handled by the GEOR. Partner can
provide a proposal for special inspection and GEOR services upon request.
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 10
5. GEOTECHNICAL RECOMMENDATIONS & PARAMETERS
The following discussion of findings for the site is based on the assumed construction, geologic review,
results of the field exploration, and laboratory testing programs. The recommendations of this report are
contingent upon adherence to Appendix C of this report, General Geotechnical Design and Construction
Considerations. For additional details on the below recommendations, please see Appendix C.
5.1 Geotechnical Recommendations
The proposed construction is generally feasible from a geotechnical perspective provided the
recommendations and assumptions of this report are followed.
Geologic/General Site Considerations
• The site is located in the City of Carlsbad within the Peninsular Ranges geomorphic province of the State
of California. Surficial geology at the site is mapped as Santiago formation deposits. The unit is Eocene
in age and form widespread deposits in this area. The site sits on top of a roughly 50 ft steep hillside and
slopes down towards the northwest. The subject property is currently developed with an office building
with associated landscaping and parking lot. The site may be impacted by existing buried foundations,
utility lines, undocumented fills as well as other remnants of previous construction and landscaping. The
site appears to have been previously undeveloped before 1988. This portion of the state is prone to
seismic ground shaking. No other geological hazards are known or suspected on the site. No other
geological hazards are known or suspected on the site.
Excavation Considerations
• We anticipate excavations on the site to depths of up to 5 feet for tank foundations and/or slabs on
grade and 5 feet for utilities. Based on our data, conventional construction equipment in good working
condition should be able to perform the planned excavations. As previously mentioned, buried utility
lines, undocumented fills as well as other remnants of previous construction may be present on the site.
Native sandy soils may contain cohesionless material which could also cave or be difficult to remove.
This may require additional planning and equipment. Groundwater was not encountered on the site in
our borings at the time of drilling. However, groundwater levels fluctuate over time and may be different
at the time of construction and during the project life.
• Appendix C further discusses excavation recommendations in the following sections, which can be
accessed by clicking hyperlinks: Earthwork, Underground Pipeline, Excavation De-Watering.
Mat Foundations
• We recommend that the new tanks and perimeter block wall be supported on mat foundations or
structural slab with a minimum 18 inch turn down at the edges and supported on a minimum of
36-inches of compacted on site soil. This can be accomplished over excavating under the
foundation system to a depth of 24 inches then scarifying moisture conditioning and recompacting
an additional 12-inches within the on-site non-expansive (PI<20) soils.
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 11
• The base of excavation for new foundations and slabs-on-grade should be evaluated by the
engineer, with additional removal of soft or deleterious material if needed and should then be
compacted in-place prior to the placement of new fills or foundations. Areas for new slabs on grade
should be evaluated by proofrolling with soft, unstable areas removed and replaced with
compacted fill.
• Section 5.2 of this report provides a table outlining the embedment depth, bearing capacity,
settlement and other parameters for foundation design and construction. Recommendations for a
deep foundation option can be provided upon request.
Auxiliary Foundations
• The proposed platforms, retaining walls, and other auxiliary structures may be supported on shallow
footings founded on 12-inches of reworked and compacted on-site non-expansive (PI<20) soils.
• Slabs-on-grade for the proposed patio areas and other flat work should be founded on 12-inches
of reworked and compacted non-expansive (PI<20) fill.
• The base of excavation for new foundations and slabs-on-grade should be evaluated by the
engineer, with additional removal of soft or deleterious material if needed and should then be
compacted in-place prior to the placement of new fills or foundations. Areas for new slabs on grade
should be evaluated by proofrolling with soft, unstable areas removed and replaced with
compacted fill.
• Proposed foundations for embedded pipes and/or poles can be designed using the methods
outlined in Title 24, Part 2, Chapter 1807.3 of the 2016 California Building Code.
• Section 5.2 of this report provides a table outlining the embedment depth, bearing capacity,
settlement and other parameters for foundation design and construction. Recommendations for a
deep foundation option can be provided upon request.
On-Grade Construction Considerations
• In new structural areas of the site, all remnants of previous construction, vegetation and/or
deleterious materials should be completely removed to exposed clean subgrade soil. In new fill,
structural, and pavement areas, cleaned subgrade should be proofrolled and evaluated by the
engineer with a loaded water truck (4,000 gallon) or equivalent rubber-tired equipment. In locations
where proofrolling is not feasible, probing, dynamic cone penetration testing, or other methods
may be employed. Soft or unstable areas should be repaired per the direction of the engineer. Once
approved, the subgrade soil should be scarified to a depth of 24 inches, moisture conditioned, and
compacted as engineered fill. Improvements in these areas should extend laterally beyond the new
structure limits 2 feet or a distance equal to or greater than the layer thickness, whichever is greater.
This zone should extend vertically from the bearing grade elevation to the base of the fill. The
thicknesses of the layer, settlement estimates, and modulus values are provided on the design
tables in the next section.
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 12
• Based on our borings, we anticipate that some over-excavation may result from proofrolling
operations. In areas where deep instability is encountered, we recommend test pits be excavated
and an engineer be called to perform an evaluation of the issue and to propose a resolution. Such
resolutions may include but are not limited to: the use of geotextiles, chemical treatments (soil
cement, hydrated lime, etc.) thickened slabs or pavements sections, lime-treated aggregate base,
or others. Pavement sections provided in Section 5.2 are based on approved, compacted in-place
soils being used in the subgrade. If subgrade conditions in the upper 3 feet of pavement areas vary
or are improved, the pavement sections may be modified.
• Appendix C provides additional recommendations for foundations in the following sections: Cast-
in-place Concrete, Foundations, Earthwork, Paving, Subgrade Preparation which can be accessed
by clicking the hyperlinks.
Soil Reuse Considerations
• Based on our borings majority of the site soils will generally be usable as structural fill provided it
is free of deleterious material. Low to non-plastic soils (PI<15), as well as existing structural materials
such as concrete, asphalt, crushed aggregate, or others could potentially be re-used as site fills if
processed to meet fill requirements on the site. We anticipate that some volume loss may occur in
native soils after compaction, and this should be accounted for in the contractor's grading
estimates. We recommend engineered fill for the site be moisture conditioned and compacted to
at least 95% of the maximum dry density in accordance with ASTM D1557 and Appendix C of this
report.
• Appendix C provides additional recommendations for foundations in the following sections:
EARTHWORK, SUBGRADE PREPARATION which can be accessed by clicking the hyperlinks.
Geotechnical Concrete and Steel Construction Considerations
• Soil/rock may be corrosive to concrete. We recommend using corrosion resistant concrete (e.g.
Type II/V Portland Cement, a fly ash mixture of 25 percent cement replacement, and a water/cement
ratio of 0.45 or less) as directed by the producer, engineer or other qualified party based on their
knowledge of the materials and site conditions. Concrete exposed to freezing weather should be
air-entrained. Mix designs should be well-established and reviewed by the project engineers prior
to placement, to verify the design is appropriate to meet the project needs and parameters
provided in this report. Quality control testing should be performed to verify appropriate mixes are
used and are properly handled and placed. Please refer to Appendix C, Cast In-Place Concrete for
more details.
• Soil/rock may be corrosive to un-protected metallic elements such as pipes, poles, rebar, etc. We
recommend the use of coatings and/or cathodic protection for metals in contact with the ground,
as directed by the product manufacturer, engineer or other qualified party based on their
knowledge of the materials to be used and site soil conditions.
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 13
Site Storm Water Considerations
• Surface drainage and landscaping design should be carefully planned to protect the new structures
from erosion/undermining, and to maintain the site earthwork and structure subgrades in a
relatively consistent moisture condition. Water should not flow towards or pond near to new
structures, and high water-demand plants should not be planned near to structures. Appendix C
provides additional recommendations for foundations in the following sections: SITE GRADING
AND DRAINAGE, WATER PROOFING which can be accessed by clicking the hyperlinks.
• We recommend consulting with the landscape designer and civil engineer regarding
management of site storm water and irrigation water, as changes in moisture content below the
site after construction will lead to soil movement and potential distress to the building.
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 18
Seismic Surcharge Equations
Combined effect of static and seismic lateral forces:
𝑷𝑨𝑬=𝑬𝟎+𝑬𝟎
𝑬𝟎=𝟎
𝟎× 𝑨× 𝑯𝟎 Resultant acting at a distance of 𝐻
3 from base of the wall
𝑬𝟎=𝟎
𝟖× 𝑲𝒉× 𝜸× 𝑯𝟎 Resultant acting at a distance of (0.6× 𝐻) from base of the wall
Where:
F1 = Static force, measured in pounds per linear foot, based on active pressure.
F2 = Seismic Lateral Force, measured in pounds per linear foot, based on seismic
pressure
γ = 120 pounds per square foot
Kh = 𝑆𝐷𝑅2.5⁄
A = Active Pressure, measured in pounds per cubic foot.
H = Height of retained soil, measured in feet.
FIGURES
• Site Vicinity Plan
• Site Exploration Plan (Aerial)
• Site Exploration Plan (Site Plan)
• Geologic Map
Camp Paia•son Sou1J1
q;
E:scol'Klido
Source: U.S. Geological Survey, 2022, US Topo 7.5-minute map for Encinitas, CA: USGS -National
Geos atial Technical O erations Center (NGTOC).
KEY
' Approximate Site Location
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
FIGURE 1 -SITE VICINITY PLAN
PARTNER
Source: Google Earth Pro, 2022
KEY
-~ Approximate Boring Locations
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
FIGURE 2 -SITE EXPLORATION PLAN (AERIAL)
Approximate Percolation Test Locations ~ ·. = Approximate Project Limits
PARTNER
•lf[ffl:
., .
• :J.
I I
5 ! :t ~ ~I
B2J
Source: Site plans provided by client
KEY
-~ Approximate Boring Locations
Geotechnical Report
Project No. 21 ·337267.5
September 18, 2022
... B i ~~ 1 ~ilcrua
I
I
I Y; I
I I
-rli:r-~------r ------1 ----c
I I
I I
I I
I I
I I
,U]l;
___ _J _______ L_~
I I
I
•llrID; H~;
I ~1i100~ I
I !Htioo;
~;;Joo~ I oo~ I f_.TR.
1.
~ a
i ~ ~I R l ll
FIGURE 3 -SITE EXPLORATION PLAN (SITE PLAN)
Approximate Percolation Test Locations ~ ·. = Approximate Project Limits
PARTNER
Source: Kennedy, M.P., Tan, S.S., Bovard, K.R., Alvarez, R.M., Watson, M.J., and Gutierrez, C./., 2007,
Geologic map of the Oceanside 30x60-minute quadrangle, California, Regional Geologic Map No. 2,
California Geological Survey, Scale 7:700,000
KEY
~ Approximate Site Location
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
El El
MillCIII RII ( .... HOlloceneJ
Wnh dopo5i11 ('-II~)
M.Nlli fan dep091b: (lolle ttolooene)
MNllll flood.pM,n do~h• (W Holooane)
l.rclRde dllposil's. "'1C!Mded (Holocene and PlelMOCIIA)
Marine belcn deposll• (lllte Holocene)
Parafic nll#li'lne depotlll !'MM: Holocene)
Undivided marl._ dtJDorirl1 a1 olflihcn t90lon Ila!• ~ne)
Marine tan dopo!IIIS (!Ille Hiob:lone)
'rol.:,g alli.rr.al fan deposlll (Hc:b:ene and \all!! Pic!110011neJ
YaungalUwil l\oadillaan ~C~ Md ._Pl&~•)
Yotslg CCIIII.MII oepoots (HolOGerie and I• Plei5locelle)
'f'tulg .. l.lNIYllllie)'~fliolocenlail!dl ... ~)
Paibll Fornllllion (4Nlrty PlelllOcona)
0Pf • undllOne adOI
0,,----
01.'iPc,inO Sprlnp Fo'mallOn (N"V FW1iooene)
\.lnltvicledMdmnsardMdrrentar)' rxltJl'I oll'!:hol9 reQ1M
(HdOOene Plelll0oene. Plooetie ltld MiOcenit)
VwyoldcalWalciec,Dl,tlr. ~ (niddlli ID Ullfy PiHlocerle)
Vw:yoltlpat:1111Cde;loMl,Ul'OYOOCl(tnddle110ot117'~ooene)
S.ndllaned Rec.'oncll Mesa CPtleoge,W}
U..JH71 v.Joy Fo,nation irnddit EOQlll!e)
Sta1t11.1rn CongbTIMlte CIWdtle Eeoene)
ff!e!S Format.on <mllldle Eoc:ill'II)
Tatl1t)' Sanchtone (~ Eocetle)
0elmat Pormi:IIOII ll'l"lidOlf 1:oce,e)
Salltlago Fonttati:ln {tl'tdOle Eocene)
~ Eooenetodl.l In lhe dllhole •rea (&cine)
Ml!IHetllf'l'll!ll'llaty •net ""8!8\'0lc.nic N:ICQ, ulld>tlded (Mtteol!oiej
MINVOlclanleclk•(~
Mlllllgn!Necockl (Maa.tdc)
Q.iaitrllle eno quaru. ~ (Mmonl11:)
FIGURE 4 -GEOLOGIC MAP
PARTNER
APPENDIX A
Boring Logs
Percolation Test Logs
PARTNER
SURFACE COVER: General discription with thickness to the inch, ex. Topsoil, Concrete, Asphalt, etc,
FILL: General description with thickness to the 0.5 feet. Ex. Roots, Debris, Processed Materials (Pea Gravel, etc.)
NATIVE GEOLOGIC MATERIAL: Deposit type, 1.Color, 2.moisture, 3.density, 4.SOIL TYPE, other notes - Thickness to 0.5 feet
1. Color - Generalized
Light Brown (usually indicates dry soil, rock, caliche)
Brown (usually indicates moist soil)
Dark Brown (moist to wet soil, organics, clays)
Reddish (or other bright colors) Brown (moist, indicates some soil development/or residual soil)
Greyish Brown (Marine, sub groundwater - not the same as light brown above)
Mottled (brown and gray, indicates groundwater fluctuations)
2. Moisture
dry - only use for wind-blown silts in the desert
damp - soil with little moisture content
moist - near optimum, has some cohesion and stickyness
wet - beyond the plastic limit for clayey soils, and feels wet to the touch for non clays
saturated - Soil below the groundwater table, sampler is wet on outside
3A. Relative Density for Granular Soils 3B. Consistency of Fine-Grained Cohesive Soils
Ring SPT Consistnecy SPT
0-7 0-4 very soft 0-2
7-14 4-10 soft 2-4
14-28 10-30 medium stiff 4-8
28-100 30-50 stiff 8-15
100+Over 50 very stiff 15-30
hard Over 30
4. Classification
Determine percent Gravel (Material larger than the No. 4 Sieve)
Determine percent fines (Material passing the No. 200 Sieve)
Determine percent sand (Passing the No. 4 and retained on the No. 200 Sieve)
Determine if clayey (make soil moist, if it easily roll into a snake it is clayey)
Coarse Grained Soils (Less than 50% Passing the No. 200 Sieve)
GP SP Mostly sand and gravel, with less than 5 % fines sandy GRAVEL SAND
GP-GM SP-SM Mostly sand and gravel 5-12% fines, non-clayey sandy GRAVEL with silt SAND with Silt
GP-GC SP-SC Mostly sand and gravel 5-12% fines, clayey sandy GRAVEL with clay SAND with clay
GC SC Mostly sand and gravel >12% fines clayey clayey GRAVEL clayey SAND
GM SM Mostly sand and gravel >12% fines non-clayey silty GRAVEL silty SAND
Fine Grained Soils (50% or more passes the No. 200 Sieve)
ML Soft, non clayey SILT with sand
MH Very rare, holds a lot of water, and is pliable with very low strength high plasticity SILT
CL If sandy can be hard when dry, will be stiff/plastic when wet CLAY with sand/silt
CH Hard and resiliant when dry, very strong/sticky when wet (may have sand in it)FAT CLAY
H = Liquid limit over 50%, L - LL under 50%
C = Clay
M = Silt
Samplers
S = Standard split spoon (SPT)
R = Modified ring
Bulk = Excavation spoils
ST = Shelby tube
C = Rock core
BORING LOG KEY - EXPLANATION OF TERMS
Over 2.0
Relative Density
very loose
loose
dense
very dense
medium dense
Undrained Shear Strength, tsf
less than 0.125
0.125 - 0.25
0.25 - 0.50
0.50 - 1.0
1.0 - 2.0
Geotechnical Report
Project No. 21-337267.5 A - 1
Boring Number: Bl Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER~ Asphalt
0.5
1
1.5
2 s 11 SM NATIVE: Light brown, damp, medium dense, silty SAND
2.5 (Moisture Content: 24.1%, Fines: 40.2%)
3
3.5
4
4.5
5 R 31 Hard
5.5
6
6.5
7 s 20 Very stiff
7.5
8
8.5
9 ------------------------------------------------------------9.5
10 R 44 SC Mottled light brown and orange brown, damp, dense, clayey SAND
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15 s 24 Light brown to white, medium dense, clayey SAND; some burnt black wood debris
15.5
16
16.5
17
17.5
18
18.5
19
19.5
20 I s 13 Light to dark brown
Cleotachnlcal Report
Project No. 21-337267.5
A -2
Boring Number: Bl Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
20 s 13 SC Light brown to brown, medium dense, clayey SAND; some burnt black wood debris
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Cleotachnlcal Report
Project No. 21-337267.5
A -3
Boring Number: 82 Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER~ Grass and topsoil
0.5
1
1.5
2 R 36 SC NATIVE: Brown, damp, dense, clayey SAND; fine sand grains
2.5
3
3.5
4
4.5
5 s 17 Hard
5.5
6
6.5
7 R 39 Very stiff
7.5
8
8.5
9 ------------------------------------------------------------9.5
10 s 11 SC Mottled light brown and orange brown, damp, dense, clayey SAND
10.5
11
11.5
12
12.5
13 ------------------------------------------------------------13.5
14
14.5
15 s 28 CL Dark brown to gray, damp, very stiff, sandy CLAY
15.5
16
16.5
17
17.5
18 ------------------------------------------------------------18.5
19
19.5
20 I s 34 ML Dark brown to gray, damp, hard, sandy SILT
Cleotachnlcal Report
Project No. 21-337267.5
A -4
Boring Number: 82 Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 9DS01
Depth, FT Sample N-Value uses Description
20 s 34 ML Dark brown to gray, damp, hard, sandy SILT
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Cleotechnlcal Report
Project No. 21-337267.5
A -5
Boring Number: B3 Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER~ Grass and topsoil
0.5
1
1.5
2 R 25 SM NATIVE: Brown, damp, medium dense, silty SAND
2.5
3
3.5
4
4.5
5 s 19
5.5
6
6.5
7 R 30 Light brown
7.5
8
8.5
9 ------------------------------------------------------------9.5
10 s 17 SC Mottled light brown and orange brown, damp, medium dense, clayey SAND
10.5
11
11.5
12
12.5 ------------------------------------------------------------13
13.5
14
14.5
15 s 28 CL Mottled dark brown, white, and orange, damp, hard, sandy CLAY
15.5
16
16.5
17
17.5
18 ------------------------------------------------------------18.5
19
19.5
20 I s 34 SM Light brown, damp, dense, silty SAND
Cleotachnlcal Report
Project No. 21-337267.5
A -6
Boring Number: 83 Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 9DS01
Depth, FT Sample N-Value uses Description
20 s 34 SM Light brown, damp, dense, silty SAND
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Cleotechnlcal Report
Project No. 21-337267.5
A -7
Boring Number: 84 Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd. Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER~ Grass and topsoil
0.5
1
1.5
2 s 11 SM NATIVE: Brown, damp, medium dense, silty SAND
2.5
3
3.5
4
4.5
5 R 32 Hard
5.5
6
6.5
7 s 17 Light brown
7.5
8
8.5
9 -----------~---~--------------------------------------------9.5
10 R 44 SC Mottled light brown and orange brown, damp, dense, clayey SAND
10.5
11
11.5
12
12.5
13 ------------------------------------------------------------13.5
14
14.5
15 s 33 CL Mottled dark brown, white, and orange, damp, hard, sandy CLAY
15.5
16
16.5
17
17.5
18 -----------~---~--------------------------------------------18.5
19
19.5
20 I s 23 SM Light brown, damp, medium dense, silty SAND
Cleotachnlcal Report
Project No. 21-337267.5
A -8
Boring Number: 84 Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 9DS01
Depth, FT Sample N-Value uses Description
20 s 23 SM Light brown, damp, medium dense, silty SAND
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Cleotechnlcal Report
Project No. 21-337267.5
A -9
Boring Number: HAl Boring Log Page 1 of 1
Location: Western Interior of Building Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, California 92008 Depth to Groundwater: NA
Project Number: 21-337267.5 Field Technician: WVA
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Concrete
0.5
1
1.5
2 I G SC Brown, damp, clayey SAND; with gravel
2.5
3
3.5
4
4.5
5 I G Light brown
5.5 Boring terminated at 5 feet bgs,
6 Backfilled with excess soil cuttings
6.5 Patched with concrete
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15
15.5
16
16.5
17
17.S
18
18.5
19
19.S
20
Cleotechnlcal Report
A -10
Boring Number: HA2 Boring Log Page 1 of 1
Location: Western Interior of Building Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, California 92008 Depth to Groundwater: NA
Project Number: 21-337267.5 Field Technician: WVA
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Concrete
0.5
1
1.5
2 I G SC Brown, damp, clayey SAND; with gravel
2.5
3
3.5
4
4.5
5 I G {Moisture Content: 17.3%, U : 36, Pl: 17, Fines: 26.4%)
5.5 Boring terminated at 5 feet bgs.
6 Backfilled with excess soil cuttings.
6.5 Patched with concrete
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15
15.5
16
16.5
17
17.S
18
18.5
19
19.S
20
Cleotechnlcal Report
A -11
PERCOLATION TEST DATA SHEET -Porchet M ethod PARTNER
Project: Carlsbad Airport Project No.: 22-337267.5 Date: I 7/25/2022
Test Hole No.: Pl Tested By: SG
Depth of Test Hole, D, (ft): 5 uses Soil Classification: CL
Casing Depth (ft): Test Hole Drameter (in): 8
Initial Depth Initial Final Head, Average Head Tested
Final Depth to Time Water Level Infiltration Start Time, t. to Water, D0 Stop Time, Tr Water, Dr (ft) Interval, tit Head, H0 Hr Drop, tiH (in) Helght, H."' Rate, I, Notes
Trial No. Date (ft) (min) (ft) (ft) (in) (in/hr)
Presoak 7/25/2022 9:12AM 1.00 11:12AM 1.47 120 4.00 3.53 5.64 45.18
Presoak 7/25/2022 0 5.00 5.00 0.00 60.00 30-min readings
1 7/25/2022 10:12 AM 1.00 11:12AM 1.46 60 4.00 3.54 5.52 45.24
2 7/25/2022 11:12AM 1.00 11:42AM 1.21 30 4.00 3.79 2.52 46.74
3 7/25/2022 11:42AM 1.00 12:12 PM 1.24 30 4.00 3.76 2.88 46.56
4 7/25/2022 12:12 PM 1.00 12:42 PM 1.34 30 4.00 3.66 4.08 45.96
5 7/25/2022 12:42 PM 1.00 1:12 PM 1.30 30 4.00 3.70 3.60 46.20
6 7/25/2022 1:12 PM 1.00 1:42 PM 1.35 30 4.00 3.65 4.20 45.90
7 7/25/2022 1:42 PM 1.00 2:12 PM 1.26 30 4.00 4 3.12 46.44
8 7/25/2022 2:12 PM 1.00 2:42 PM 1.13 30 4.00 4 1.56 47.22 0.13
Comments: 1. Percolation test was performed in accordance with the EXHIBIT 7.111 -TECHNICAL GUIDANCE DOCUMENT (TGD) FOR THE PREPARATION OF CONCEPTUAL/PRELIMINARY AND/OR PROJECT WATER QUALITY
MANAGEMENT PLANS (WQMPs), dated December 20, 2013.
2. Weather:
PERCOLATION TEST DATA SHEET -Porchet M ethod PARTNER
Project: Carlsbad Airport Project No.: 22-337267.5 Date.: I 7/25/2022
Test Hole No.: P2 Tested By: SG
Depth of Test Hole, D, (ft): 5 uses Soil Classification: CL
Casing Depth (ft): Test Hole Drameter (in): 8
Initial Depth Initial Final Head, Average Head Tested
Final Depth to Time Water Level Infiltration Start nme, t. to Water, D0 Stop Time, Tr Water, Dr (ft) Interval, tit Head, H0 Hr Drop, tiH (in) Helght, H."' Rate, I, Notes
Trial No. Date (ft) (min) (ft) (ft) (in) (in/hr)
Presoak 7/25/2022 9:00AM 1.00 10:00AM 1.10 60 4.00 3.90 1.20 47.40
Presoak 7/25/2022 0 5.00 5.00 0.00 60.00 30-min readings
1 7/25/2022 10:00 AM 1.10 10:30AM 1.10 30 3.90 3.90 0.00 46.80
2 7/25/2022 10:30AM 1.10 11:00AM 1.13 30 3.90 3.87 0.36 46.62
3 7/25/2022 11:00AM 1.10 11:30AM 1.14 30 3.90 3.86 0.48 46.56
4 7/25/2022 11:30AM 1.10 12:00 PM 1.17 30 3.90 3.83 0.84 46.38
5 7/25/2022 12:00PM 1.10 12:30 PM 1.17 30 3.90 3.83 0.84 46.38
6 7/25/2022 12:30 PM 1.10 1:00PM 1.18 30 3.90 3.82 0.96 46.32
7 7/25/2022 1:00PM 1.10 1:30PM 1.12 30 3.90 4 0.24 46.68
8 7/25/2022 1:30PM 1.10 2:00PM 1.13 30 3.90 4 0.36 46.62 0.03
Comments: 1. Percolation test was performed in accordance with the EXHIBIT 7.111 -TECHNICAL GUIDANCE DOCUMENT (TGD) FOR THE PREPARATION OF CONCEPTUAL/PRELIMINARY AND/OR PROJECT WATER QUALITY
MANAGEMENT PLANS (WQMPs), dated December 20, 2013.
2. Weather:
APPENDIX B
Lab Data
PARTNER
PLASTICITY INDEX DATA
Symbol Boring Depth, ft Natural Moisture Plasticity Index Plastic Limit Liquid Limit
40
5:
x-
Cl)
-0 .: 30
?:-u .:;
"' "' ci: 20
10
Content(%)
15.7
24.1 ± 17
NP _l 18
NP
GRO UP -,
.)
l 36
NP
0 +----"-+---+---+----+----+----+----+----+----+----l
0 10 20 30 40 so 60 70 80 90 100
Liquid Limit,%
Group and uses Symbols I Soil Descriptions
GROUP 1 -ML SM, GM, OL* SILTS, SANDS, AND GRAVELS WITH NO TO MEDIUM PLASTICITY -------
GROUP 1.5 -ML-CL SM-SC, GM-GC, OL* CLAYS, SILTS, SANDS, AND GRAVELS WITH LOW PLASTICITY
GROUP 2-CL SC, GC, OL* CLAYS, SANDS, AND GRAVELS WITH LOW TO MEDIUM PLASTICITY
GROUP 3 -MH, SM, GM, OH* SILTS, SANDS, AND GRAVELS WITH NO TO HIGH PLASTICITY
GROUP 4-CH, SC, GC, OH* CLAYS, SANDS, AND GRAVELS WITH HIGH PLASTICITY
*Or combinations of any within the same group (example fv1L-Sfv1 or CL-SC)
J
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 8-i
PARTNER
INDEX TEST DATA
Depth, ft Plasticity Plastic Liquid Moisture Percent Passing
HA-2 __ s __ _
B1 2.5 _....___ ___,__
Geotechnical Report
Project No. 21-337267.5
September 18, 2022
Page 8-ii
Index Limit Limit Content (%) the No. 200
Sieve
17.3 26.4
24.1 40.2
PARTNER
m
HAMILTON
& Associates
ATTERBERG LIMITS
ASTM D4318
Project Name: Partner -Carlsbad Solvent Tanks
Project No.: 22-3153 ------------Boring No. : Core 2 ------------Sam p I e No.: ------------
Tested By: JR --------Checked By: --------Depth (ft.): 5 --------Date: 8/22/2021
Visual Sample Description: Sandy Clay -----------------------------PLASTIC LIMIT
Number of Blows [NJ:
Tare No.:
Wt. of Tare (gm):
Wet Wt. of Soil+ Tare (gm):
Dry Wt. of Soil+ Tare (gm):
Moisture Content(%) [Wn]:
Liquid Limit
Plastic Limit
Plasticity Index
uses Classification
1
J-1
15.60
22.40
21.40
17.24
Pl at "A" -Line = 0.73(LL-20) =I 11.4804
One -Point Liquid Limit Calculation
LL =Wn(N/25) 0-121
PROCEDURES USED
33.00 □ Wet Preparation 32.00
Multipoint -Wet
31.00
00 Dry Preparation 30.00
Multipoint -Dry -::!2. ~ 29.00 c
00 Q)
Procedure A c 28.00
0
Multipoint Test (.) 27.00 ~
:J
□ in 26.00
Procedure B ·5
~ 25.00 One-point Test
24.00
23.00
10
2
P-5
15.60
22.30
21 .20
19.64
60
-50 ~
~ 40
"C -= 30 ~
0
'; 20
ns
ii: 10
0
7
0
LIQUID LIMIT
1 2
35 22
8-1 A-9
15.60 15.50
45.60 45.50
38.10 37.00
33.33 39.53
For classification or fine-
grained soils and fine-
grained fraction or coarse-
grained soils
3 4
17
A-2
15.70
45.70
37.90
35.14
CH or OH
"A"-Line
MH or OH
10 20 30 40 50 60 70 80 90 100
Liquid Limit (LL)
20 25 30 40 so 60 70 so ooOO
Number of Blows
Plate E-1
m
HAMILTO N
& Associates
ATTERBERG LIMITS
ASTM D4318
Project Name: Partner -Carlsbad Solvent Tanks
Project No.: 22-3153 -------------Boring No.: 8-1 -------------Sam p I e No.: -------------
Tested By: JR --------Checked By: --------Depth (ft.): 2.5 Feet --------Date: 8/19/2022
Visual Sample Description: Silty Sand, very fine grains, Unable to run -sand
PLASTIC LIMIT
Number of Blows [NJ:
Tare No.:
Wt. of Tare (gm):
Wet Wt. of Soil+ Tare (gm):
Dry Wt. of Soil+ Tare (gm):
Moisture Content(%) [Wn]:
Liquid Limit
Plastic Limit
Plasticity Index
uses Classification
1
NP
Pl at "A" -Line = 0.73(LL-20) =I -14.6
One -Point Liquid Limit Calculation
LL =Wn(N/25) 0-121
PROCEDURES USED
33.00
□ Wet Preparation 32.00
Multipoint -Wet
31.00
00 Dry Preparation 30.00 ~ Multipoint -Dry 0
c 29.00
Q)
00 Procedure A c 28.00
0
Multipoint Test () 27.00 Q) '-::J
□ vi 26.00
Procedure B ·o
2 25.00 One-point Test
24.00
23.00
10
2
NP
LIQUID LIMIT
1 2 3 4
NP NP NP
60 ~---------~-------
For classification or fine-
grained soils and fine-
grained fraction or coarse-
grained soils
C orOH
A"-Line
MH or OH
0 10 20 30 40 50 60 70 80 90 100
Liquid Limit (LL)
20 25 30 40 50 60 70 80 9(100
Number of Blows
Plate E-1
Ii I ii No. 200 Wash and Grain Analysis
HAMILTON ASTM D 1140
& Associates
Project Name: Partner-Carlsbad Solvent Tanks ----------------Project No.: 2.2-3153 ----------------Boring No.: B-1 ----------------Sam p I e No.: ----------------
Tested By: JR
Checked By: -----Depth (ft.): 2.5
Date: 8/22/2022
Soil Description: Clayey Silt, moist, firm/soft greyish brown, orange specks ----=--=--....;.._ __ .;....._ ___ -=-....:a...----;.__--=---=-----
Moisture Determination
Tare No. TA-1
Tare Weight (g) 3.9
Wet Weight of Soil plus Tare (g) 96.5
Oven Dried Weight of Soil plus Tare (g) 78.5
Moisture Content (%) 24.1
Grain Analysis
Post #200 Wash Mass of Oven Dried Soil for 49.4 Grain Analysis plus Tare {g)
Mass of Soil Retained on Seive (q) 3" 0.0
1 1/2" 0.0
1" 0.0
3/4" 0.0
3/8" 0.0
#4 1.1
#10 2.8
#20 5.0
#40 6.5
#60 6.4
#100 10.1
#140 7.3
#200 5.4
Pass #200 0.9
1.5
58.3 % Sand
40.2
1% Gravel
% Fines
Plate G-1
Ii I ii No. 200 Wash and Grain Analysis
HAMILTON ASTM D 1140
& Associates
Project Name: Partner-Carlsbad Solvent Tanks ----------------Project No.: 2.2-3153 ----------------Boring No.: Core 2 ----------------Sam p I e No.: ----------------
Tested By: JR
Checked By: -----Depth (ft.): 5
Date: 8/22/2022
Soil Description: Sandy clayey silt, firm, tan/grey with orange specks -----...::....--=---=---.;...._-..;..__-=-----:..-----=----=-----
Moisture Determination
Tare No. B-7
Tare Weight (g) 3.7
Wet Weight of Soil plus Tare (g) 73.4
Oven Dried Weight of Soil plus Tare (g) 63.1
Moisture Content (%) 17.3
Grain Analysis
Post #200 Wash Mass of Oven Dried Soil for 48.3 Grain Analysis plus Tare {g)
Mass of Soil Retained on Seive (q) 3" 0.0
1 1/2" 0.0
1" 0.0
3/4" 0.0
3/8" 0.0
#4 0.0
#10 0.0
#20 2.0
#40 6.8
#60 9.9
#100 13.6
#140 7.6
#200 3.8
Pass #200 0.9
0.0
73.6 % Sand
26.4
1% Gravel
% Fines
Plate G-2
APPENDIX C
General Geotechnical Design and Construction Considerations
Subgrade Preparation
Earthwork – Structural Fill/Excavations
Underground Pipeline Installation – Structural Backfill
Cast-in-Place Concrete
Foundations
Laterally Loaded Structures
Excavations and Dewatering
Waterproofing and Drainage
Chemical Treatment of Soils
Paving
Site Grading and Drainage
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-i
SUBGRADE PREPARATION
1. In general, construction should proceed per the project specifications and contract documents, as
well as governing jurisdictional guidelines for the project site, including but not limited to the
applicable State Department of Transportation, City and/or County, Army Corps of Engineers,
Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other governing
standard details and specifications. In areas where multiple standards are applicable the more
stringent should be considered. Work should be performed by qualified, licensed contractors with
experience in the specific type of work in the area of the site.
2. Subgrade preparation in this section is considered to apply to the initial modifications to existing
site conditions to prepare for new planned construction.
3. Prior to the start of subgrade preparation, a detailed conflict study including as-builts, utility
locating, and potholing should be conducted. Existing features that are to be demolished should
also be identified and the geotechnical study should be referenced to determine the need for
subgrade preparation, such as over-excavation, scarification and compaction, moisture
conditioning, and/or other activities below planned new structural fills, slabs on grade, pavements,
foundations, and other structures.
4. The site conflicts, planned demolitions, and subgrade preparation requirements should be
discussed in a pre-construction meeting with the pertinent parties, including the geotechnical
engineer, inspector, contractors, testing laboratory, surveyor, and others.
5. In the event of preparations that will require work near to existing structures to remain in-place,
protection of the existing structures should be considered. This also includes a geotechnical review
of excavations near to existing structures and utilities and other concerns discussed in General
Geotechnical Design and Construction Considerations, EARTHWORK and UNDERGROUND
PIPELINE INSTALLATION.
6. Features to be demolished should be completely removed and disposed of per jurisdictional
requirements and/or other conditions set forth as a part of the project. Resulting excavations or
voids should be backfilled per the recommendations in the General Geotechnical Design and
Construction Considerations, EARTHWORK section.
7. Vegetation, roots, soils containing organic materials, debris and/or other deleterious materials on
the site should be removed from structural areas and should be disposed of as above. Replacement
of such materials should be in accordance with the recommendations in the General Geotechnical
Design and Construction Considerations, EARTHWORK section
8. Subgrade preparation required by the geotechnical report may also call for as over-excavation,
scarification and compaction, moisture conditioning, and/or other activities below planned
structural fills, slabs on grade, pavements, foundations, and other structures. These requirements
should be provided within the geotechnical report. The execution of this work should be observed
by the geotechnical engineering representative or inspector for the site. Testing of the subgrade
preparation should be performed per the recommendations in the General Geotechnical Design
and Construction Considerations, EARTHWORK section.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-ii
9. Subgrade Preparation cannot be completed on frozen ground or on ground that is not at a proper
moisture condition. Wet subgrades may be dried under favorable weather if they are disked and/or
actively worked during hot, dry, weather, when exposed to wind and sunlight. Frozen ground or
wet material can be removed and replaced with suitable material. Dry material can be pre-soaked
or can have water added and worked in with appropriate equipment. The soil conditions should be
monitored by the geotechnical engineer prior to compaction. Following this type of work, approved
subgrades should be protected by direction of surface water, covering, or other methods, otherwise,
re-work may be needed.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-iii
EARTHWORK – STRUCTURAL FILL
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable State Department of Transportation, City and/or
County, Army Corps of Engineers, Federal Aviation, Occupational Safety and Health Administration
(OSHA), and any other governing standard details and specifications. In areas where multiple
standards are applicable the more stringent should be considered. Work should be performed by
qualified, licensed contractors with experience in the specific type of work in the area of the site.
2. Earthwork in this section is considered to apply to the re-shaping and grading of soil, rock, and
aggregate materials for the purpose of supporting man-made structures. Where earthwork is
needed to raise the elevation of the site for the purpose of supporting structures or forming slopes,
this is referred to as the placement of structural fill. Where lowering of site elevations is needed
prior to the installation of new structures, this is referred to as earthwork excavations.
3. Prior to the start of earthwork operations, the geotechnical study should be referenced to
determine the need for subgrade preparation, such as over-excavation or scarification and
compaction of unsuitable soils below planned structural fills, slabs on grade, pavements,
foundations, and other structures. These required preparations should be discussed in a pre-
construction meeting with the pertinent parties, including the geotechnical engineer, inspector,
contractors, testing laboratory, surveyor, and others. The preparations should be observed by the
inspector or geotechnical engineer representative, and following such subgrade preparation, the
geotechnical engineer should observe the prepared subgrade to approve it for the placement of
earthwork fills or new structures.
4. Structural fill materials should be relatively free of organic materials, man-made debris,
environmentally hazardous materials, and brittle, non-durable aggregate, frozen soil, soil clods or
rocks and/or any other materials that can break down and degrade over time.
5. In deeper structural fill zones, expansive soils (greater than 1.5 percent swell at 100 pounds per
square foot surcharge) and rock fills (fills containing particles larger than 4 inches and/or containing
more than 35 percent gravel larger than ¾-inch diameter or more than 50 percent gravel) may be
used with the approval and guidance of the geotechnical report or geotechnical engineer. This may
require the placement of geotextiles or other added costs and/or conditions. These conditions may
also apply to corrosive soils (less than 2,000 ohm-cm resistivity, more than 50 ppm chloride content,
more than 0.1 percent sulfates)
6. For structural fill zones that are closer in depth below planed structures, low expansive materials,
and materials with smaller particle size are generally recommended, as directed by the geotechnical
report (see criteria above in 5). This may also apply to corrosive soils.
7. For structural fill materials, in general the compaction equipment should be appropriate for the
thickness of the loose lift being placed, and the thickness of the loose lift being placed should be
at least two times the maximum particle size incorporated in the fill.
8. Fill lift thickness (including bedding) should generally be proportioned to achieve 95 percent or
more of a standard proctor (ASTM D689) maximum dry density (MDD) or 90 percent or more of a
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-iv
modified proctor (ASTM D1557) MDD, depending on the state practices. For subgrades below
roadways, the general requirement for soil compaction is usually increased to 100 percent or more
of the standard proctor MDD and 95 percent or more of the modified proctor MDD.
9. Soil compaction should be performed at a moisture content generally near optimum moisture
content determined by either standard or modified proctor, and ideally within 3 percent below to
1 percent over the optimum for a standard proctor, and from 2 percent below to 2 percent above
optimum for a modified proctor.
10. In some instances, fill areas are difficult to access. In such cases a low-strength soil-cement slurry
can be used in the place of compacted fill soil. In general, such fills should be rated to have a 28-
day strength of 75 to 125 psi, which in some areas is referred to as a “1-sack” slurry. It should be
noted that these materials are wet during placement and require a period of 2 days (24 hours) to
cure before additional fill can be placed above them. Testing of this material can be done using
concrete cylinder compression strength testing equipment, but care is needed in removing the test
specimens from the molds. Field testing using the ball method and spread, or flow testing is also
acceptable.
11. For fills to be placed on slopes, benching of fill lifts is recommended, which may require cutting
into existing slopes to create a bench perpendicular to the slope where soil can be placed in a
relatively horizontal orientation. For the construction of slopes, the slopes should be over-built and
cut back to grade, as the material in the outer portion of the slope may not be well compacted.
12. For subgrade below roadways, runways, railways or other areas to receive dynamic loading, a
proofroll of the finished, compacted subgrade should be performed by the geotechnical engineer
or inspector prior to the placement of structural aggregate, asphalt or concrete. Proofrolling
consists of observing the performance of the subgrade under heavy-loaded equipment, such as
full, 4,000 Gallon water truck, loaded tandem-axel dump truck or similar. Areas that exhibit
instability during proofroll should be marked for additional work prior to approval of the subgrade
for the next stage of construction.
13. Quality control testing should be provided on earthwork. Proctor testing should be performed on
each soil type, and one-point field proctors should be used to verify the soil types during
compaction testing. If compaction testing is performed with a nuclear density gauge, it should be
periodically correlated with a sand cone test for each soil type. Density testing should be performed
per project specifications and or jurisdictional requirements, but not less than once per 12 inches
elevation of any fill area, with additional tests per 12-inch fill area for each additional 7,500 square-
foot section or portion thereof.
14. For earthwork excavations, OSHA guidelines should be referenced for sloping and shoring.
Excavations over a depth of 20 feet require a shoring design. In the event excavations are planned
near to existing structures, the geotechnical engineer should be consulted to evaluate whether such
excavation will call for shoring or underpinning the adjacent structure. Pre-construction and post-
construction condition surveys and vibration monitoring might also be helpful to evaluate any
potential damage to surrounding structures.
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15. Excavations into rock, partially weathered rock, cemented soils, boulders and cobbles, and other
hard soil or “hard-pan” materials, may result in slower excavation rates, larger equipment with
specialized digging tools, and even blasting. It is also not unusual in these situations for screening
and or crushing of rock to be called for. Blasting, hard excavating, and material processing
equipment have special safety concerns and are more costly than the use of soil excavation
equipment. Additionally, this type of excavation, especially blasting, is known to cause vibrations
that should be monitored at nearby structures. As above, a pre-blast and post-blast conditions
assessment might also be warranted.
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UNDERGROUND PIPELINE – STRUCTURAL BACKFILL
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable State Department of Transportation, the State
Department of Environmental Quality, the US Environmental Protection Agency, City and/or County
Public Works, Occupational Safety and Health Administration (OSHA), Private Utility Companies,
and any other governing standard details and specifications. In areas where multiple standards are
applicable the more stringent should be considered, and in some cases, work may take place to
multiple different standards. Work should be performed by qualified, licensed contractors with
experience in the specific type of work in the area of the site.
2. Underground pipeline in this section is considered to apply to the installation of underground
conduits for water, storm water, irrigation water, sewage, electricity, telecommunications, gas, etc.
Structural backfill refers to the activity of restoring the grade or establishing a new grade in the
area where excavations were needed for the underground pipeline installation.
3. Prior to the start of underground pipeline installation, a detailed conflict study including as-builts,
utility locating, and potholing should be conducted. The geotechnical study should be referenced
to determine subsurface conditions such as caving soils, unsuitable soils, shallow groundwater,
shallow rock and others. In addition, the utility company responsible for the line also will have
requirements for pipe bedding and support as well as other special requirements. Also, if the
underground pipeline traverses other properties, rights-of-way, and/or easements etc. (for roads,
waterways, dams, railways, other utility corridors, etc.) those owners may have additional
requirements for construction.
4. The required preparations above should be discussed in a pre-construction meeting with the
pertinent parties, including the geotechnical engineer, inspector, contractors, testing laboratory,
surveyor, and other stake holders.
5. For pipeline excavations, OSHA guidelines should be referenced for sloping and shoring.
Excavations over a depth of 20 feet require a shoring design. In the event excavations are planned
near to existing structures or pipelines, the geotechnical engineer should be consulted to evaluate
whether such excavation will call for shoring or supporting the adjacent structure or pipeline. A pre-
construction and post-construction condition survey and vibration monitoring might also be
helpful to evaluate any potential damage to surrounding structures.
6. Excavations into rock, partially weathered rock, cemented soils, boulders and cobbles, and other
hard soil or “hard-pan” materials, may result in slower excavation rates, larger equipment with
specialized digging tools, and even blasting. It is also not unusual in these situations for screening
and or crushing of rock to be called for. Blasting, hard excavating and material processing
equipment have special safety concerns and are more costly than the use soil excavation
equipment. Additionally, this type of excavation, especially blasting, is known to cause vibrations
that should be monitored at nearby structures. As above, a pre-blast and post-blast conditions
assessment might also be warranted.
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7. Bedding material requirements vary between utility companies and might depend of the type of
pipe material and availability of different types of aggregates in different locations. In general,
bedding refers to the material that supports the bottom of the pipe, and extends to 1 foot above
the top of the pipe. In general the use of aggregate base for larger diameter pipes (6-inch diameter
or more) is recommended lacking a jurisdictionally specified bedding material. Gas lines and smaller
diameter lines are often backfilled with fine aggregate meeting the ASTM requirements for concrete
sand. In all cases bedding with less than 2,000 ohm-cm resistivity, more than 50 ppm chloride
content or more than 0.1 percent sulfates should not be used.
8. Structural backfill materials above the bedding should be relatively free of organic materials, man-
made debris, environmentally hazardous materials, frozen material, and brittle, non-durable
aggregate, soil clods or rocks and/or any other materials that can break down and degrade over
time.
9. In general the backfill soil requirements will depend on the future use of the land above the buried
line, but in most cases, excessive settlement of the pipe trench is not considered advisable or
acceptable. As such, the structural backfill compaction equipment should be appropriate for the
thickness of the loose lift being placed. The thickness of the loose lift being placed should be at
least two times the maximum particle size incorporated in the fill. Care should be taken not to
damage the pipe during compaction or compaction testing.
10. Fill lift thickness (including bedding) should generally be proportioned to achieve 95 percent or
more of a standard proctor (ASTM D689) maximum dry density (MDD) or 90 percent or more of a
modified proctor (ASTM D1557) MDD, depending on the state practices (in general the modified
proctor is required in California and for projects in the jurisdiction of the Army Corps of Engineers).
For backfills within the upper poritons of roadway subgrades, the general requirement for soil
compaction is usually increased to 100 percent or more of the standard proctor MDD and 95
percent or more of the modified proctor MDD.
11. Soil compaction should be performed at a moisture content generally near optimum moisture
content determined by either standard or modified proctor, and ideally within 3 percent below to
1 percent over the optimum for a standard proctor, and from 2 percent below to 2 percent above
optimum for a modified proctor.
12. In some instances fill areas are difficult to access. In such cases a low-strength soil-cement slurry
can be used in the place of compacted fill soil. In general such fills should be rated to have a 28-
day strength of 75 to 125 psi, which in some areas is referred to as a “1-sack” slurry. It should be
noted that these materials are wet, and require a period of 2 days (24 hours) to cure before
additional fill can be placed above it. Testing of this material can be done using concrete cylinder
compression strength testing equipment, but care is needed in removing the test specimens from
the molds. Field testing using the ball method, and spread or flow testing is also acceptable.
13. Quality control testing should be provided on structural backfill to assist the contractor in meeting
project specifications. Proctor testing should be performed on each soil type, and one-point field
proctors should be used to verify the soil types during compaction testing. If compaction testing is
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performed with a nuclear density gauge, it should be periodically correlated with a sand cone test
for each soil type.
14. Density testing should be performed on structural backfill per project specifications and or
jurisdictional requirements, but not less than once per 12 inches elevation in each area, and
additional tests for each additional 500 linear-foot section or portion thereof.
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CAST-IN-PLACE CONCRETE
SLABS-ON-GRADE/STRUCTURES/PAVEMENTS
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, City and/or County, Army Corps of
Engineers, Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other
governing standard details and specifications. In areas where multiple standards are applicable the
more stringent should be considered. Work should be performed by qualified, licensed contractors
with experience in the specific type of work in the area of the site.
2. Cast-in-place concrete (concrete) in this section is considered to apply to the installation of cast-
in-place concrete slabs on grade, including reinforced and non-reinforced slabs, structures, and
pavements.
3. In areas where concrete is bearing on prepared subgrade or structural fill soils, testing and approval
of this work should be completed prior to the beginning of concrete construction.
4. In locations where a concrete is approved to bear on in-place (native) soil or in locations where
approved documented fills have been exposed to weather conditions after approval, a concrete
subgrade evaluation should be performed prior to the placement of reinforcing steel and or
concrete. This can consist of probing with a “t”-handled rod, borings, penetrometer testing,
dynamic cone penetration testing and/or other methods requested by the geotechnical engineer
and/or inspector. Where unsuitable, wet, or frozen bearing material is encountered, the
geotechnical engineer should be consulted for additional recommendations.
5. Slabs on grade should be placed on a 4-inch thick or more capillary barrier consisting of non-
corrosive (more than 2,000 ohm-cm resistivity, less than 50 ppm chloride content and less than 0.1
percent sulfates) aggregate base or open-graded aggregate material. This material should be
compacted or consolidated per the recommendations of the structural engineer or otherwise would
be covered by the General Considerations for EARTHWORK.
6. Depending on the site conditions and climate, vapor barriers may be required below in-door grade-
slabs to receive flooring. This reduces the opportunity for moisture vapor to accumulate in the slab,
which could degrade flooring adhesive and result in mold or other problems. Vapor barriers should
be specified by the structural engineer and/or architect. The installation of the barrier should be
inspected to evaluate the correct product and thickness is used, and that it has not been damaged
or degraded.
7. At times when rainfall is predicted during construction, a mud-mat or a thin concrete layer can be
placed on prepared and approved subgrades prior to the placement of reinforcing steel or tendons.
This serves the purpose of protecting the subgrades from damage once the reinforcement
placement has begun.
8. Prior to the placement of concrete, exposed subgrade or base material and forms should be wetted,
and form release compounds should be applied. Reinforcement support stands or ties should be
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checked. Concrete bases or subgrades should not be so wet that they are softened or have standing
water.
9. For a cast-in-place concrete, the form dimensions, reinforcement placement and cover, concrete
mix design, and other code requirements should be carefully checked by an inspector before and
during placement. The reinforcement should be specified by the structural engineering drawings
and calculations.
10. For post-tension concrete, an additional check of the tendons is needed, and a tensioning
inspection form should be prepared prior to placement of concrete.
11. For Portland cement pavements, forms an additional check of reinforcing dowels should performed
per the design drawings.
12. During placement, concrete should be tested, and should meet the ACI and jurisdictional
requirements and mix design targets for slump, air entrainment, unit weight, compressive strength,
flexural strength (pavements), and any other specified properties. In general concrete should be
placed within 90 minutes of batching at a temperature of less than 90 degrees Fahrenheit. Adding
of water to the truck on the jobsite is generally not encouraged.
13. Concrete mix designs should be created by the accredited and jurisdictionally approved supplier to
meet the requirements of the structural engineer. In general a water/cement ratio of 0.45 or less is
advisable, and aggregates, cement, flyash, and other constituents should be tested to meet ASTM
C-33 standards, including Alkali Silica Reaction (ASR). To further mitigate the possibility of concrete
degradation from corrosion and ASR, Type II or V Portland Cement should be used, and fly ash
replacement of 25 percent is also recommended. Air entrained concrete should be used in areas
where concrete will be exposed to frozen ground or ambient temperatures below freezing.
14. Control joints are recommended to improve the aesthetics of the finished concrete by allowing for
cracking within partially cut or grooved joints. The control joints are generally made to depths of
about 1/4 of the slab thickness and are generally completed within the first day of construction.
The spacing should be laid out by the structural engineer, and is often in a square pattern. Joint
spacing is generally 5 to 15 feet on-center but this can vary and should be decided by the structural
engineer. For pavements, construction joints are generally considered to function as control joints.
Post-tensioned slabs generally do not have control joints.
15. Some slabs are expected to meet flatness and levelness requirements. In those cases, testing for
flatness and levelness should be completed as soon as possible, usually the same day as concrete
placement, and before cutting of control joints if possible. Roadway smoothness can also be
measured, and is usually specified by the jurisdictional owner if is required.
16. Prior to tensioning of post-tension structures, placement of soil backfills or continuation of building
on newly-placed concrete, a strength requirement is generally required, which should be specified
by the structural engineer. The strength progress can be evaluated by the use of concrete
compressive strength cylinders or maturity monitoring in some jurisdictions. Advancing with
backfill, additional concrete work or post-tensioning without reaching strength benchmarks could
result in damage and failure of the concrete, which could result in danger and harm to nearby
people and property.
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17. In general, concrete should not be exposed to freezing temperatures in the first 7 days after
placement, which may require insulation or heating. Additionally, in hot or dry, windy weather,
misting, covering with wet burlap or the use of curing compounds may be called for to reduce
shrinkage cracking and curling during the first 7 days.
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FOUNDATIONS
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, City and/or County, Army Corps of
Engineers, Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other
governing standard details and specifications. In areas where multiple standards are applicable the
more stringent should be considered. Work should be performed by qualified, licensed contractors
with experience in the specific type of work in the area of the site.
2. Foundations in this section are considered to apply to the construction of structural supports which
directly transfer loads from man-made structures into the earth. In general, these include shallow
foundations and deep foundations. Shallow foundations are generally constructed for the purpose
of distributing the structural loads horizontally over a larger area of earth. Some types of shallow
foundations (or footings) are spread footings, continuous footings, mat foundations, and reinforced
slabs-on-grade. Deep foundations are generally designed for the purpose of distributing the
structural loads vertically deeper into the soil by the use of end bearing and side friction. Some
types of deep foundations are driven piles, auger-cast piles, drilled shafts, caissons, helical piers,
and micro-piles.
3. For shallow foundations, the minimum bearing depth considered should be greater than the
maximum design frost depth for the location of construction. This can be found on frost depth
maps (ICC), but the standard of practice in the city and/or county should also be consulted. In
general the bearing depth should never be less than 18 inches below planned finished grades.
4. Shallow continuous foundations should be sized with a minimum width of 18 inches and isolated
spread footings should be a minimum of 24 inches in each direction. Foundation sizing, spacing,
and reinforcing steel design should be performed by a qualified structural engineer.
5. The geotechnical engineer will provide an estimated bearing capacity and settlement values for the
project based on soil conditions and estimated loads provided by the structural engineer. It is
assumed that appropriate safety factors will be applied by the structural engineer.
6. In areas where shallow foundations are bearing on prepared subgrade or structural fill soils, testing
and approval of this work should be completed prior to the beginning of foundation construction.
7. In locations where the shallow foundations are approved to bear on in-place (native) soil or in
locations where approved documented fills have been exposed to weather conditions after
approval, a foundation subgrade evaluation should be performed prior to the placement of
reinforcing steel. This can consist of probing with a “t”-handled rod, borings, penetrometer testing,
dynamic cone penetration testing and/or other methods requested by the geotechnical engineer
and/or inspector. Where unsuitable foundation bearing material is encountered, the geotechnical
engineer should be consulted for additional recommendations.
8. For shallow foundations to bear on rock, partially weathered rock, hard cemented soils, and/or
boulders, the entire foundation system should bear directly on such material. In this case, the rock
surface should be prepared so that it is clean, competent, and formed into a roughly horizontal,
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stepped base. If that is not possible, then the entire structure should be underlain by a zone of
structural fill. This may require the over-excavation in areas of rock removal and/or hard dig. In
general this zone can vary in thickness but it should be a minimum of 1 foot thick. The geotechnical
engineer should be consulted in this instance.
9. At times when rainfall is predicted during construction, a mud-mat or a thin concrete layer can be
placed on prepared and approved subgrades prior to the placement of reinforcing steel. This serves
the purpose of protecting the subgrades from damage once the reinforcing steel placement has
begun.
10. For cast-in-place concrete foundations, the excavations dimensions, reinforcing steel placement
and cover, structural fill compaction, concrete mix design, and other code requirements should be
carefully checked by an inspector before and during placement.
-----------------------------------------------------------------------------------------------------
11. For deep foundations, the geotechnical engineer will generally provide design charts that provide
foundations axial capacity and uplift resistance at various depths given certain-sized foundations.
These charts may be based on blow count data from drilling and or laboratory testing. In general
safety factors are included in these design charts by the geotechnical engineer.
12. In addition, the geotechnical engineer may provide other soil parameters for use in the lateral
resistance analysis. These parameters are usually raw data, and safety factors should be provided
by the shaft designer. Sometimes, direct shear and or tri-axial testing is performed for this analysis.
13. In general the spacing of deep foundations is expected to be 6 shaft diameters or more. If that
spacing is reduced, a group reduction factor should be applied by the structural engineer to the
foundation capacities per FHWA guidelines. The spacing should not be less than 2.5 shaft diameters.
14. For deep foundations, a representative of the geotechnical engineer should be on-site to observe
the excavations (if any) to evaluate that the soil conditions are consistent with the findings of the
geotechnical report. Soil/rock stratigraphy will vary at times, and this may result in a change in the
planned construction. This may require the use of fall protection equipment to perform
observations close to an open excavation.
15. For driven foundations, a representative of the geotechnical engineer should be on-site to observe
the driving process and to evaluate that the resistance of driving is consistent with the design
assumptions. Soil/rock stratigraphy will vary at times and may this may result in a change in the
planned construction.
16. For deep foundations, the size, depth, and ground conditions should be verified during construction
by the geotechnical engineer and/or inspector responsible. Open excavations should be clean, with
any areas of caving and groundwater seepage noted. In areas below the groundwater table, or
areas where slurry is used to keep the trench open, non-destructive testing techniques should be
used as outlined below.
17. Steel members including structural steel piles, reinforcing steel, bolts, threaded steel rods, etc.
should be evaluated for design and code compliance prior to pick-up and placement in the
foundation. This includes verification of size, weight, layout, cleanliness, lap-splices, etc. In addition,
if non-destructive testing such as crosshole sonic logging or gamma-gamma logging is required,
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access tubes should be attached to the steel reinforcement prior to placement, and should be
relatively straight, capped at the bottom, and generally kept in-round. These tubes must be filled
with water prior to the placement of concrete.
18. In cases where steel welding is required, this should be observed by a certified welding inspector.
19. In many cases, a crane will be used to lower steel members into the deep foundations. Crane picks
should be carefully planned, including the ground conditions at placement of outriggers, wind
conditions, and other factors. These are not generally provided in the geotechnical report, but can
usually be provided upon request.
20. Cast-in-place concrete, grout or other cementations materials should be pumped or distributed to
the bottom of the excavation using a tremmie pipe or hollow stem auger pipe. Depending on the
construction type, different mix slumps will be used. This should be carefully checked in the field
during placement, and consolidation of the material should be considered. Use of a vibrator may
be called for.
21. For work in a wet excavation (slurry), the concrete placed at the bottom of the excavation will
displace the slurry as it comes up. The upper layer of concrete that has interacted with the slurry
should be removed and not be a part of the final product.
22. Bolts or other connections to be set in the top after the placement is complete should be done
immediately after final concrete placement, and prior to the on-set of curing.
23. For shafts requiring crosshole sonic logging or gamma-gamma testing, this should be performed
within the first week after placement, but not before a 2 day curing period. The testing company
and equipment manufacturer should provide more details on the requirements of the testing.
24. Load testing of deep foundations is recommended, and it is often a project requirement. In some
cases, if test piles are constructed and tested, it can result in a significant reduction of the amount
of needed foundations. The load testing frame and equipment should be sized appropriately for
the test to be performed, and should be observed by the geotechnical engineer or inspector as it
is performed. The results are provided to the structural engineer for approval.
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LATERALLY LOADED STRUCTURES - RETAINING WALLS/SLOPES/DEEP
FOUNDATIONS/MISCELLANEOUS
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, City and/or County, Army Corps of
Engineers, Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other
governing standard details and specifications. In areas where multiple standards are applicable the
more stringent should be considered. Work should be performed by qualified, licensed contractors
with experience in the specific type of work in the area of the site.
2. Laterally loaded structures for this section are generally meant to describe structures that are
subjected to loading roughly horizontal to the ground surface. Such structures include retaining
walls, slopes, deep foundations, tall buildings, box culverts, and other buried or partially buried
structures.
3. The recommendations put forth in General Geotechnical Design and Construction Considerations
for FOUNDATIONS, CAST-IN-PLACE CONCRETE, EARTHWORK, and SUBGRADE PREPARATION
should be reviewed, as they are not all repeated in this section, but many of them will apply to the
work. Those recommendations are incorporated by reference herein.
4. Laterally loaded structures are generally affected by overburden pressure, water pressure,
surcharges, and other static loads, as well as traffic, seismic, wind, and other dynamic loads. The
structural engineer must account for these loads. In addition, eccentric loading of the foundation
should be evaluated and accounted for by the structural engineer. The structural engineer is also
responsible for applying the appropriate factors of safety to the raw data provided by the
geotechnical engineer.
5. The geotechnical report should provide data regarding soil lateral earth pressures, seismic design
parameters, and groundwater levels. In the report the pressures are usually reported as raw data in
the form of equivalent fluid pressures for three cases. 1. Static is for soil pressure against a structure
that is fixed at top and bottom, like a basement wall or box culvert. 2. Active is for soil pressure
against a wall that is free to move at the top, like a retaining wall. 3. Passive is for soil that is resisting
the movement of the structure, usually at the toe of the wall where the foundation and embedded
section are located. The structural engineer is responsible for deciding on safety factors for design
parameters and groundwater elevations based on the raw data in the geotechnical report.
6. Generally speaking, direct shear or tri-axial shear testing should be performed for this evaluation in
cases of soil slopes or unrestrained soil retaining walls over 6 feet in height or in lower walls in some
cases based on the engineer’s judgment. For deep foundations and completely buried structures,
this testing will be required per the discretion of the structural engineer.
7. For non-confined retaining walls (walls that are not attached at the top) and slopes, a geotechnical
engineer should perform overall stability analysis for sliding, overturning, and global stability. For
walls that are structurally restrained at the top, the geotechnical engineer does not generally
perform this analysis. Internal wall stability should be designed by the structural engineer.
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8. Cut slopes into rock should be evaluated by an engineering geologist, and rock coring to identify
the orientation of fracture plans, faults, bedding planes, and other features should be performed.
An analysis of this data will be provided by the engineering geologist to identify modes of failure
including sliding, wedge, and overturning, and to provide design and construction
recommendations.
9. For laterally loaded deep foundations that support towers, bridges or other structures with high
lateral loads, geotechnical reports generally provide parameters for design analysis which is
performed by the structural engineer. The structural engineer is responsible for applying
appropriate safety factors to the raw data from the geotechnical engineer.
10. Construction recommendations for deep foundations can be found in the General Geotechnical
Design and Construction Considerations-FOUNDATIONS section.
11. Construction of retaining walls often requires temporary slope excavations and shoring, including
soil nails, soldier piles and lagging or laid-back slopes. This should be done per OSHA requirements
and may require specialty design and contracting.
12. In general, surface water should not be directed over a slope or retaining wall, but should be
captured in a drainage feature trending parallel to the slope, with an erosion protected outlet to
the base of the wall or slope.
13. Waterproofing for retaining walls is generally required on the backfilled side, and they should be
backfilled with an 18-inch zone of open graded aggregate wrapped in filter fabric or a synthetic
draining product, which outlets to weep holes or a drain at the base of the wall. The purpose of this
zone, which is immediately behind the wall is to relieve water pressures from building behind the
wall.
14. Backfill compaction around retaining walls and slopes requires special care. Lighter equipment
should be considered, and consideration to curing of cementitious materials used during
construction will be called for. Additionally, if mechanically stabilized earth walls are being
constructed, or if tie-backs are being utilized, additional care will be necessary to avoid damaging
or displacing the materials. Use of heavy or large equipment, and/or beginning of backfill prior to
concrete strength verification can create dangers to construction and human safety. Please refer to
the General Geotechnical Design and Construction Considerations-CAST-IN-PLACE CONCRETE
section. These concerns will also apply to the curing of cell grouting within reinforced masonry
walls.
15. Usually safety features such as handrails are designed to be installed at the top of retaining walls
and slopes. Prior to their installation, workers in those areas will need to be equipped with
appropriate fall protection equipment.
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EXCAVATION AND DEWATERING
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, City and/or County, Army Corps of
Engineers, Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other
governing standard details and specifications. In areas where multiple standards are applicable the
more stringent should be considered. Work should be performed by qualified, licensed contractors
with experience in the specific type of work in the area of the site.
2. Excavation and Dewatering for this section are generally meant to describe structures that are
intended to create stable, excavations for the construction of infrastructure near to existing
development and below the groundwater table.
3. The recommendations put forth in General Geotechnical Design and Construction Considerations
for LATERALLY LOADED STRUCTURES, FOUNDATIONS, CAST-IN-PLACE CONCRETE, EARTHWORK,
and SUBGRADE PREPARATION should be reviewed, as they are not all repeated in this section, but
many of them will apply to the work. Those recommendations are incorporated by reference herein.
4. The site excavations will generally be affected by overburden pressure, water pressure, surcharges,
and other static loads, as well as traffic, seismic, wind, and other dynamic loads. The structural
engineer must account for these loads as described in Section 5.2 of this report. In addition,
eccentric loading of the foundation should be evaluated and accounted for by the structural
engineer. The structural engineer is also responsible for applying the appropriate factors of safety
to the raw data provided by the geotechnical engineer.
5. The geotechnical report should provide data regarding soil lateral earth pressures, seismic design
parameters, and groundwater levels. In the report the pressures are usually reported as raw data in
the form of equivalent fluid pressures for three cases. 1. Static is for soil pressure against a structure
that is fixed at top and bottom, like a basement wall or box culvert. 2. Active is for soil pressure
against a wall that is free to move at the top, like a retaining wall. 3. Passive is for soil that is resisting
the movement of the structure, usually at the toe of the wall where the foundation and embedded
section are located. The structural engineer is responsible for deciding on safety factors for design
parameters and groundwater elevations based on the raw data in the geotechnical report.
6. The parameters provided above are based on laboratory testing and engineering judgement. Since
numerous soil layers with different properties will be encountered in a large excavation,
assumptions and judgement are used to generate the equivalent fluid pressures to be used in
design. Factors of safety are not included in those numbers and should be evaluated prior to design.
7. Groundwater, if encountered will dramatically change the stability of the excavation. In addition,
pumping of groundwater from the bottom of the excavation can be difficult and costly, and it can
result in potential damage to nearby structures if groundwater drawdown occurs. As such, we
recommend that groundwater monitoring be performed across the site during design and prior to
construction to assist in the excavation design and planning.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xviii
8. Groundwater pumping tests should be performed if groundwater pumping will be needed during
construction. The pumping tests can be used to estimate drawdown at nearby properties, and also
will be needed to determine the hydraulic conductivity of the soil for the design of the dewatering
system.
9. For excavation stabilization in granular and dense soil, the use of soldier piles and lagging is
recommended. The soldier pile spacing and size should be determined by the structural engineer
based on the lateral loads provided in the report. In general, the spacing should be more than two
pile diameters, and less than 8 feet. Soldier piles should be advanced 5 feet or more below the base
of the excavation. Passive pressures from Section 5.2 can be used in the design of soldier piles for
the portions of the piles below the excavation.
10. If the piles are drilled, they should be grouted in-place. If below the groundwater table, the grouting
should be accomplished by tremmie pipe, and the concrete should be a mix intended for placement
below the groundwater table. For work in a wet excavation, the concrete placed at the bottom of
the excavation will displace the water as it comes up. The upper layer of concrete that has interacted
with the water should be removed and not be a part of the final product. Lagging should be
specially designed timber or other lagging. The temporary excavation will need to account for
seepage pressures at the toe of the wall as well as hydrostatic forces behind the wall.
11. Depending on the loading, tie back anchors and/or soil nails may be needed. These should be
installed beyond the failure envelope of the wall. This would be a plane that is rotated upward 55
degrees from horizontal. The strength of the anchors behind this plane should be considered, and
bond strength inside the plane should be ignored. If friction anchors are used, they should extend
10 feet or more beyond the failure envelope. Evaluation of the anchor length and encroachment
onto other properties, and possible conflicts with underground utilities should be carefully
considered. Anchors are typically installed 25 to 40 degrees below horizontal. The capacity of the
anchors should be checked on 10% of locations by loading to 200% of the design strength. All
should be loaded to 120% of design strength, and should be locked off at 80%
12. The shoring and tie backs should be designed to allow less than ½ inch of deflection at the top of
the excavation wall, where the wall is within an imaginary 1:1 line extending downward from the
base of surrounding structures. This can be expanded to 1 inch of deflection if there is no nearby
structure inside that plane. An analysis of nearby structures to locate their depth and horizontal
position should be conducted prior to shored excavation design.
13. Assuming that the excavations will encroach below the groundwater table, allowances for drainage
behind and through the lagging should be made. The drainage can be accomplished by using an
open-graded gravel material that is wrapped in geotextile fabric. The lagging should allow for the
collected water to pass through the wall at select locations into drainage trenches below the
excavation base. These trenches should be considered as sump areas where groundwater can be
pumped out of the excavation.
14. The pumped groundwater needs to be handled properly per jurisdictional guidelines.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xix
15. In general, surface water should not be directed over a slope or retaining wall, but should be
captured in a drainage feature trending parallel to the slope, with an erosion protected outlet to
the base of the wall or slope.
16. Safety features such as handrails or barriers are to be designed to be installed at the top of retaining
walls and slopes. Prior to their installation, workers in those areas will need to be equipped with
appropriate fall protection equipment.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xx
Waterproofing and Back Drainage
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, City and/or County, Army Corps of
Engineers, Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other
governing standard details and specifications. In areas where multiple standards are applicable the
more stringent should be considered. Work should be performed by qualified, licensed contractors
with experience in the specific type of work in the area of the site.
2. Waterproofing and Back drainage structures for this section are generally meant to describe
permanent subgrade structures that are planned to be below the historic high groundwater
elevation of 20 feet below existing grades.
3. The recommendations put forth in General Geotechnical Design and Construction Considerations
for FOUNDATIONS, CAST-IN-PLACE CONCRETE, EARTHWORK, and SUBGRADE PREPARATION
should be reviewed, as they are not all repeated in this section, but many of them will apply to the
work. Those recommendations are incorporated by reference herein.
4. In general, surface water should not be directed over a slope or retaining wall, but should be
captured in a drainage feature trending parallel to the slope, with an erosion protected outlet to
the base of the wall or slope.
5. Waterproofing for retaining walls is generally required on the backfilled side, and they should be
backfilled with an 18-inch zone of open graded aggregate wrapped in filter fabric or a synthetic
draining product, which outlets to weep holes or a drain at the base of the wall. The purpose of this
zone, which is immediately behind the wall is to relieve water pressures from building behind the
wall.
6. For the basement walls on this site, sump pumps will be needed to reduce the build-up of water in
the basement. The design should be for a historic high groundwater level of 20 feet bgs. The
pumping system should be designed to keep the slab and walls relatively dry so that mold,
efflorescence, and other detrimental effects to the concrete structure will not result.
7. Backfill compaction around retaining walls and slopes requires special care. Lighter equipment
should be considered, and consideration to curing of cementitious materials used during
construction will be called for. Additionally, if mechanically stabilized earth walls are being
constructed, or if tie-backs are being utilized, additional care will be necessary to avoid damaging
or displacing the materials. Use of heavy or large equipment, and/or beginning of backfill prior to
concrete strength verification can create dangers to construction and human safety. Please refer to
the General Geotechnical Design and Construction Considerations-CAST-IN-PLACE CONCRETE
section. These concerns will also apply to the curing of cell grouting within reinforced masonry
walls.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xxi
CHEMICAL TREATMENT OF SOIL
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, State Department of Environmental
Quality, the US Environmental Protection Agency, City and/or County, Army Corps of Engineers,
Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other governing
standard details and specifications. In areas where multiple standards are applicable the more
stringent should be considered. Work should be performed by qualified, licensed contractors with
experience in the specific type of work in the area of the site.
2. Chemical treatment of soil for this section is generally meant to describe the process of improving
soil properties for a specific purpose, using cement or chemical lime.
3. A mix design should be performed by the geotechnical engineer to help it meet the specific
strength, plasticity index, durability, and/or other desired properties. The mix design should be
performed using the proposed chemical lime or cement proposed for use by the contractor, along
with samples of the site soil that are taken from the material to be used in the process.
4. For the mix design the geotechnical engineer should perform proctor testing to determine
optimum moisture content of the soil, and then mix samples of the soil at 3 percent above optimum
moisture content with varying concentrations of lime or cement. The samples will be prepared and
cured per ASTM standards, and then after 7-days for curing, they will be tested for compression
strength. Durability testing goes on for 28 days.
5. Following this testing, the geotechnical engineer will provide a recommended mix ratio of cement
or chemical lime in the geotechnical report for use by the contractor. The geotechnical engineer
will generally specify a design ratio of 2 percent more than the minimum to account for some error
during construction.
6. Prior to treatment, the in-place soil moisture should be measured so that the correct amount of
water can be used during construction. Work should not be performed on frozen ground.
7. During construction, special considerations for construction of treated soils should be followed. The
application process should be conducted to prevent the loss of the treatment material to wind
which might transport the materials off site, and workers should be provided with personal
protective equipment for dust generated in the process.
8. The treatment should be applied evenly over the surface, and this can be monitored by use of a
pan placed on the subgrade. This can also be tested by preparing test specimens from the in-place
mixture for laboratory testing.
9. Often, after or during the chemical application, additional water may be needed to activate the
chemical reaction. In general, it should be maintained at about 3 percent or more above optimum
moisture. Following this, mixing of the applied material is generally performed using specialized
equipment.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xxii
10. The total amount of chemical provided can be verified by collecting batch tickets from the delivery
trucks, and the depth of the treatment can be verified by digging of test pits, and the use of reagents
that react with lime and or cement.
11. For the use of lime treatment, compaction should be performed after a specified amount of time
has passed following mixing and re-grading. For concrete, compaction should be performed
immediately after mixing and re-grading. In both cases, some swelling of the surface should be
expected. Final grading should be performed the following day of the initial work for lime treatment,
and within 2 to 4 hours for soil cement.
12. Quality control testing of compacted treated subgrades should be performed per the
recommendations of the geotechnical report, and generally in accordance with General
Geotechnical Design and Construction Considerations - EARTHWORK
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xxiii
PAVING
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, City and/or County, Army Corps of
Engineers, Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other
governing standard details and specifications. In areas where multiple standards are applicable the
more stringent should be considered. Work should be performed by qualified, licensed contractors
with experience in the specific type of work in the area of the site.
2. Paving for this section is generally meant to describe the placement of surface treatments on travel-
ways to be used by rubber-tired vehicles, such as roadways, runways, parking lots, etc.
3. The geotechnical engineer is generally responsible for providing structural analysis to recommend
the thickness of pavement sections, which can include asphalt, concrete pavements, aggregate
base, cement or lime treated aggregate base, and cement or lime treated subgrades.
4. The civil engineer is generally responsible for determining which surface finishes and mixes are
appropriate, and often the owner, general contractor and/or other party will decide on lift thickness,
the use of tack coats and surface treatments, etc.
5. The geotechnical engineer will generally be provided with the planned traffic loading, as well as
reliability, design life, and serviceability factors by the jurisdiction, traffic engineer, designer, and/or
owner. The geotechnical study will provide data regarding soil resiliency and strength. A pavement
modeling software is generally used to perform the analysis for design, however, jurisdictional
minimum sections also must be considered, as well as construction considerations and other
factors.
6. The geotechnical report report will generally provide pavement section thicknesses if requested.
7. For construction of overlays, where new pavement is being placed on old pavement, an evaluation
of the existing pavement is needed, which should include coring the pavement, evaluation of the
overall condition and thickness of the pavement, and evaluation of the pavement base and
subgrade materials.
8. In general, the existing pavement is milled and treated with a tack coat prior to the placement of
new pavement for the purpose of creating a stronger bond between the old and new material. This
is also a way of removing aged asphalt and helping to maintain finished grades closer to existing
conditions grading and drainage considerations.
9. If milling is performed, a minimum of 2 inches of existing asphalt should be left in-place to reduce
the likelihood of equipment breaking through the asphalt layer and destroying its integrity. After
milling and before the placement of tack coat, the surface should be evaluated for cracking or
degradation. Cracked or degraded asphalt should be removed, spanned with geosynthetic
reinforcement, or be otherwise repaired per the direction of the civil and or geotechnical engineer
prior to continuing construction. Proofrolling may be requested.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xxiv
10. For pavements to be placed on subgrade or base materials, the subgrade and base materials should
be prepared per the General Geotechnical Design and Construction Considerations – EARTHWORK
section.
11. Following the proofrolling as described in the General Geotechnical Design and Construction
Considerations – EARTHWORK section, the application of subgrade treatment, base material, and
paving materials can proceed per the recommendations in the geotechnical report and/or project
plans. The placement of pavement materials or structural fills cannot take place on frozen ground.
12. The placement of aggregate base material should conform to the jurisdictional guidelines. In
general the materials should be provided by an accredited supplier, and the material should meet
the standards of ASTM C-33. Material that has been stockpiled and exposed to weather including
wind and rain should be retested for compliance since fines could be lost. Frozen material cannot
be used.
13. The placement of asphalt material should conform to the jurisdictional guidelines. In general the
materials should be provided by an accredited supplier, and the material should meet the standards
of ASTM C-33. The material can be placed in a screed by end-dumping, or it can be placed directly
on the paving surface. The temperature of the mix at placement should generally be on the order
of 300 degrees Fahrenheit at time of placement and screeding.
14. Compaction of the screeded asphalt should begin as soon as practical after placement, and initial
rolling should be performed before the asphalt has cooled significantly. Compaction equipment
should have vibratory capabilities, and should be of appropriate size and weight given the thickness
of the lift being placed and the sloping of the ground surface.
15. In cold and/or windy weather, the cooling of the screeded asphalt is a quality issue, so preparations
should be made to perform screeding immediately after placement, and compaction immediately
after screeding.
16. Quality control testing of the asphalt should be performed during placement to verify compaction
and mix design properties are being met and that delivery temperatures are correct. Results of
testing data from asphalt laboratory testing should be provided within 24 hours of the paving.
PARTNER
Geotechnical Report
Project No. 22-337267.5
September 18, 2022
Page C-xxv
SITE GRADING AND DRAINAGE
1. In general, construction should proceed per the governing jurisdictional guidelines for the project
site, including but not limited to the applicable American Concrete Institute (ACI), International
Code Council (ICC), State Department of Transportation, State Department of Environmental
Quality, the US Environmental Protection Agency, City and/or County, Army Corps of Engineers,
Federal Aviation, Occupational Safety and Health Administration (OSHA), and any other governing
standard details and specifications. In areas where multiple standards are applicable the more
stringent should be considered. Work should be performed by qualified, licensed contractors with
experience in the specific type of work in the area of the site.
2. Site grading and drainage for this section is generally meant to describe the effect of new
construction on surface hydrology, which impacts the flow of rainfall or other water running across,
onto or off-of, a newly constructed or modified development.
3. This section does not apply to the construction of site grading and drainage features.
Recommendations for the construction of such features are covered in General Geotechnical Design
and Construction Considerations for Earthwork – Structural Fills section and Underground Pipeline
Installation – Backfill section.
4. In general, surface water flows should be directed towards storm drains, natural channels, retention
or detention basins, swales, and/or other features specifically designed to capture, store, and or
transmit them to specific off-site outfalls.
5. The surface water flow design is generally performed by a site civil engineer, and it can be impacted
by hydrology, roof lines, and other site structures that do not allow for water to infiltrate into the
soil, and that modify the topography of the site.
6. Soil permeability, density, and strength properties are relevant to the design of storm drain systems,
including dry wells, retention basins, swales, and others. These properties are usually only provided
in a geotechnical report if specifically requested, and recommendations will be provided in the
geotechnical report in those cases.
7. Structures or site features that are not a part of the surface water drainage system should not be
exposed to surface water flows, standing water or water infiltration. In general, roof drains and
scuppers, exterior slabs, pavements, landscaping, etc. should be constructed to drain water away
from structures and foundations. The purpose of this is to reduce the opportunity for water damage,
erosion, and/or altering of structural soil properties by wetting. In general, a 5 percent or more
slope away from foundations, structural fills, slopes, structures, etc. should be maintained.
8. Special considerations should be used for slopes and retaining walls, as described in the General
Geotechnical Design and Construction Considerations - LATERALLY LOADED STRUCTURES section.
9. Additionally, landscaping features including irrigation emitters and plants that require large
amounts of water should not be placed near to new structures, as they have the potential to alter
soil moisture states. Changing of the moisture state of soil that provides structural support can lead
to damage to the supported structures.
PARTNER
APPENDIX D
Liquefaction Analysis
PARTNER
GEOTECHNICAL REPORT ADDENDUM 1
PARTNER
PARTNER ___________________________________ ___....,.,... ____ _
August 10, 2023
Greg Holmquist
Nitto Denko Technical Corp
501 Via Del Monte
Oceanside, California 92058
Subject: Addendum No. 1 -Response to City Comments
Geotechnical Report
Solvent Tank Farm and Interior Platforms -Carlsbad Airport
1935 Camino Vida Roble
Carlsbad, California 92008
Partner Project No. 21-337267.5
Dear Greg Holmquist:
Partner Assessment Corporation (Partner) performed a geotechnical investigation for the proposed Solvent
Tank Farm and Interior Platforms to be located at 1935 Camino Vida Roble in Carlsbad, California, and
summarized the results in a report dated September 18, 2022. The City of Carlsbad (The City) requested a
third-party review of our report by Ninyo & Moore Geotechnical & Environmental Sciences Consultants
(N&M). A list of review comments was provided in their letter dated July 10, 2023 (N&M Project Number
No. 109343020).
This letter presents our responses to the N&M comments, as listed below:
N&M Comment 1: The Geotechnicol Consultant should review the project grading and foundation plans
and provide any additional geotechnicol recommendations, as appropriate, and indicate if the plans hove
been prepared in accordance with the geotechnicol recommendations provided in the referenced
geotechnicol report (Portner, 2022)
RESPONSE: We were provided with the following construction drawings for the subject property in
order to perform a review of aspects in the plans related to the referenced Partner Geotechnical Report
dated March 22, 2022:
• KPFF (unsealed), Grading plans for 1935 Camino Vida Roble (Kinovate Production Facility Tl), 1935
Camino Vida Roble, Carlsbad, CA, plan date 05/30/2023, 13 pages
• The Austin Company (Sealed by M. Omar Sheikh, SE), Structural Plans, Production Facility Tenant
lmprovment, 1935 Camino Vida Roble, Carlsbad, CA 92008, plan date 06/16/2023, S-000 through
S-733 (38 pages)
We reviewed the plans as described in the table below:
Plan Set Plan Sheets Description Items Reviewed
Grading Plans
Grading Plan
Grading Plan
(800) 419-4926
Title Sheet
Grading Plan
Civil Details
Soils Engineer Certificate Note
Site Layout
Retaining Wall Sections
Subgrade compaction Requirements
Pavement Sections
www.PARTNEResi.com
Addendum No. 1 - Response to Review Comments
Project No. 22-391842.1
August 24, 2023
Page 3
N&M Comment 5: In the “Project Data” table under Section 2.2 “Assumed Construction” of the referenced
geotechnical report (Partner, 2022), the sentence under the “Type of Construction” looks to be cut short.
The Geotechnical Consultant should clarify this project description.
RESPONSE: Type of Construction in the “Project Data” table under Section 2.2 “Assumed Construction”
should read “Stainless steel solvent tanks on concrete pad with masonry walls, four new platforms with
grade beam and Slab on Grade.”
N&M Comment 6: Section 2.3 “References” in the referenced geotechnical report (Partner, 2022)
mentions of the usage of a geologic map for an area in San Bernardino County. The Geotechnical
Consultant should update this reference.
RESPONSE: The correct reference for the geologic map should read ”Kennedy, M.P., Tan, S.S., Bovard, K.R.,
Alvarez, R.M., Watson, M.J., and Gutierrez, C.I., 2007, Geologic map of the Oceanside 30x60-minute quadrangle,
California, Regional Geologic Map No. 2, California Geological Survey, Scale 1:100,000.”
N&M Comment 7: Section 4.2 “Groundwater” in the referenced geotechnical report (Partner, 2022)
provides discussion about the historical high groundwater being at a depth of 5 feet below the
groundwater surface. Since the site is described as being at the top of a 50-foot high slope, the
Geotechnical Consultant should consider further expanding on the groundwater discussion to incorporate
the sloping aspects of the site boundaries.
RESPONSE: Our estimation of the historical high groundwater was based off our review of the Site
Conceptual Model and Quarterly Groundwater Monitoring report prepared for the former Air Resorts
Airline Facility by SCS Engineers and dated January 10, 2008. The former Air Resorts Airline Facility is
located approximately 2/3 of a mile to the northwest and at a higher elevation then the subject site.
The historic high groundwater elevation given in our report was intended to be a conservative estimate
for planning purposes; however, we do not anticipate groundwater will have an impact on site
construction or long term performance at this elevation or any deeper elevation where it might occur
in the future. Groundwater was not encountered in our borings to depths of 21.5 feet below current
grades.
N&M Comment 8: Section 4.4 “Infiltration Tests” in the referenced geotechnical report (Partner, 2022)
indicates that percolation testing was performed in accordance with the County of San Diego standards.
The Geotechnical Consultant should indicate if the infiltration testing was performed in accordance with
the 2023 City of Carlsbad BMP Design Manual and provide any additional information as indicated in
Appendix D of the manual.
RESPONSE: The infiltration testing was performed in accordance with the 2023 City of Carlsbad BMP
Design Manual. Appendix D, Table D.2-3: Determination of Safety Factor and Form I-8 – Categorizing
of Infiltration Feasibility, are attached at the end of this addendum to assist with the design of
stormwater infiltration systems.
N&M Comment 9: On Page 11 of the referenced geotechnical report (Partner, 2022), under “On-Grade
Construction Considerations,” there is discussion for the scarification of the subgrade soils to a depth of
24 inches. The Geotechnical Consultant should clarify if this recommendations is intended to read as an
overexcavation or a scarification process.
RESPONSE: The 24-inches was a typo, the On-Grade Construction Considerations should read “Once
Addendum No. 1 - Response to Review Comments
Project No. 22-391842.1
August 24, 2023
Page 4
approved, the subgrade soil should be scarified to a depth of 12 inches, moisture conditioned, and
compacted as engineered fill.”
N&M Comment 10: On Page 12 of the referenced geotechnical report (Partner, 2022), under “Soil Reuse
Considerations,” there is discussion regarding the reuse of low to non-plastic soils with a plasticity index
(PI) less than 15. However, other sections of the report reference low to non-plastic soils as consisting of a
PI of less than 20. The Geotechnical Consultant should clarify which plasticity index is appropriate.
RESPONSE: Soils should be considered expensive if the PI is above 20.
N&M Comment 11: On Page 12 of the referenced geotechnical report (Partner, 2022), under “Soil Reuse
Considerations,” there are recommendations for engineered fill to be placed at a relative compaction of
95 percent as evaluated by ASTM International (ASTM) D 1557. However, Appendix C recommends the
placement of engineered fill at a relative compaction of 95 percent as evaluated by ASTM D 698 or 90
percent of ASTM D1557. The Geotechnical Consultant should clarify which recommendation is intended.
RESPONSE: Engineered fill should be moisture conditioned to within 3% of optimum moisture content
and compacted to a relative compaction of 95 percent as evaluated by ASTM International (ASTM) D
1557 for granular soils. Cohesive soils should be moisture conditioned to 3% over optimum moisture
content and compacted to a relative compaction of 90 percent as evaluated by ASTM International
(ASTM) D 1557.
N&M Comment 12: The “Prepared Subgrade Parameters” table under Section 5.2 “Geotechnical
Parameters” of the referenced geotechnical report (Partner, 2022) provides recommendations for the
coefficients of friction and bearing values for various foundation types. Since there is no direct shear or
other strength test data presented in the report, Geotechnical Consultant should provide discussion as to
how these design parameters were developed.
RESPONSE: The allowable bearing pressure that is provided in our report is what is allowed to keep
settlement below 1 inch and not the allowable capacity before bearing failure occurs. Laboratory testing
of the near surface soils show an average dry density of 95 pcf, and 35% passing the 200 sieve. Based
on correlations provided in Figure 7 - Correlations of Strength Characteristics for granular soils in
Chapter 3 of the Soil Mechanics Design Manual 7.01 from the Naval Facilities Engineering Command
(NAVFAC DM7.01) a conservative friction angle of 26 degrees can be assumed based off an average dry
unit weight of 95 and the lowest provided relative compaction on the NAVFAC figure. Using Terzaghi’s
bearing Capacity Formulas with a factor of safety of three, a friction angle of 26 degrees, and a very
conservative estimate of 200 psf for cohesion results in an allowable capacity that is higher than what
is allowed and still keep settlement under 1 inch. Laboratory test results for in situ dry density and
moisture are presented at the end of this addendum.
N&M Comment 13: The “Prepared Subgrade Parameters" table under Section 5.2 “Geotechnical
Parameters” of the referenced geotechnical report (Partner, 2022) provides estimates for the settlements
associated with various foundation types. As noted earlier, as-built site grading plans (City of Carlsbad,
1990) indicate the presence of fills up to approximately 35 feet deep or more. Accordingly, the native soils
encountered may be existing fills. The referenced geotechnical report (Partner, 2022) does not include
discussion or background information regarding the as-graded compaction levels of the existing fills or
present any consolidation test results. The Geotechnical Consultant should provide backup information
and further justification for the estimated settlements.
RESPONSE: The subject site is Lot 4 of the Carlsbad tract 81-46. Based on our review of the Report of
Addendum No. 1 - Response to Review Comments
Project No. 22-391842.1
August 24, 2023
Page 5
Geotechnical Services for the Carlsbad Tract 81-46 Airport business Center prepared by More and Taber
and dated February 25, 1987, fill was placed for the Carlsbad tract 81-46 between November 1985 and
November 1986. A total of 2,503 tests were taken within this time and compaction efforts were observed
on a continuous basis. Areas with failing tests was removed, reworked, and/or recompacted and
checked by additional testing. The Moore and Taber report notes that the subject site (Lot 4) had a cut
slope that needed stabilization or buttresses fill along the southerly facing slope at the south edge of
the site.
Given the generally granular nature of the fill in the upper 10 to 14 feet of the area of planned new
construction, our settlement estimates are based on an elastic settlement as outlined in Schmertmann
(1970), "Static Cone to Compute Settlement of Sand" ASCE Journal of the Soil Mechanics and
Foundations Division, Vol. 96, No. SM3,P. 1011-1043 and Schmertmann (1978), "Improved Strain
Influence Factor Diagrams" ASCE Journal of the Geotechnical Engineering Division, Vol.104, No. GT8,P.
1131-1135
N&M Comment 14: The “Prepared Subgrade Parameters" table under Section 5.2 "Geotechnical
Parameters” of the referenced geotechnical report (Partner, 2022) provides estimates for the differential
settlements associated with various foundation types. The Geotechnical Consultant should indicate over
what horizontal distance are the estimated differential settlements to occur over.
RESPONSE: Differential settlement can be assumed to happen over a horizontal distance of 30 feet.
N&M Comment 15: The “Paving Structural Sections” table on Page 15 of the referenced geotechnical
report (Partner, 2022) recommends a concrete pavement section thickness of 3 inches for light duty
parking areas. The Geotechnical Consultant should provide backup information and further justification
for this recommended pavement thickness.
RESPONSE: The required pavement and base thicknesses will depend on the expected wheel loads,
traffic index (TI), and the R-value of the subgrade soils. We have conservatively assumed an R-value of
35 for the design of pavement sections established on the Clayey Sandy material encountered near
surface on site.
AC pavement for surface parking shall be designed in accordance with the CATRANS method. The below
table summarizes our pavement recommendations for the assumed TI’s listed.
Depending on the planned changes to site grading, and the availability of clean granular soil, different
pavement sections would be appropriate. These can also be adjusted using treatment using soil cement.
The following sections are provided for native soil subgrade conditions. If imported fill is used, the
section may need to be adjusted. This information assumes that construction will proceed per the
provided Construction Considerations, presented in Appendix C or our original Geotech report.
REVISED FIGURES
• Site Vicinity Plan
• Site Exploration Plan (Aerial)
• Site Exploration Plan (Site Plan)
• Geologic Map
Camp P«la'eton Sou1J1 ~\
sanMarcos
Rancho san1a Fe
q;
E:scol'Klido
w
• • • I I • I •
Geos atial Technical O erations Center (NGTOC).
KEY
' Approximate Site Location
Geotechnical Report
Project No. 21-337267.5
August 24, 2023 PARTNER
Source: Google Earth Pro, 2022
KEY
-~ Approximate Boring Locations
Geotechnical Report
Project No. 21-337267.5
August 24, 2023
FIGURE 2 -SITE EXPLORATION PLAN (AERIAL)
Approximate Percolation Test Locations r . -,A . P . L' . ._ . _; pprox1mate roJect 1m1ts
PARTNER
Source: Site plans provided by client
KEY
-~ Approximate Boring Locations
Geotechnical Report
Project No. 21-337267.5
August 24, 2023
' '
......
L u.nucn:a 10 -.n rr a.lWIDIS ,. Rao
FIGURE 3 -SITE EXPLORATION PLAN (SITE PLAN)
Approximate Percolation Test Locations r . -,A . P . L' . ._ . _; pprox1mate roJect 1m1ts
PARTNER
Source: Kennedy, M.P., Tan, S.S., Bovard, K.R., Alvarez, R.M., Watson, M.J., and Gutierrez, C.I., 2007,
Geologic map of the Oceanside 30x60-minute quadrangle, California, Regional Geologic Map No. 2,
California Geolo ical Surve , Scale 1:700,000
KEY
~ Approximate Site Location
Geotechnical Report
Project No. 21-337267.5
August 24, 2023
El El
MillCIII RII ( .... HOlloceneJ
Wnh do1>0$ill ('-II~)
M.Nlli fan dep091b: (lolle ttolooene)
MNilll flood.pM,n do~h• (W Holomne)
l.rclRde dllposil's. "'1C!Mded lHolocen• and PlelMOCIIA)
Marine belcn deposll• (lllte Holocene)
Parafic uu.nne oepotlll !'MM: Holocene)
Undivided marl._ dtJ.Qor;rl1 a1 olflihcn 190lon Ila!• ~ne)
Marine tan dopo!IIIS (!Ille Hiob:lone)
'rol.:,g alli.rr.al fan deposlll (Hc:b:ene and \all!! Pic!110011neJ
Yculgaftl.lwill\oad.plllln~C~Alld-PI&~•)
Yotslg CCIIIIMII oepoots (HolOGerie and I• Plei5locelle)
'f'tulg .. l.lNIYllllie)'~(t'kllO(:ienlandl•~)
Paubll Fornllllion (4Nlrty PlelllOcona)
0Pf • undllOne adOI
0,,----
01.'iPc,inO Sprlnp Fo'mallOn (N"V FW11ooene)
\.lnltvicledMdmnsardMdrrentar)' rxltJl'I oll'!:hol9 reQ1M
(HdOOene PlelMootM. Ptiocltie ltld MiOcenit)
VwyoldcalWalClepol,tlr..~(niddll!IDe,lllfy~)
Vw:yoltlpat:1111Cde;loMl,Ul'OYOOCl(tnddle110ot117'~ooene)
S.ndllaned Rec.'oncll Mesa CPtleoge,W}
U..JiOf'I v.Joy Fo,nation irnddit EOQlll!e)
Sta1t11.1rn CongbTIMlte CIWdtle Eeoene)
ff!e!S Format.on <middle Eoc:ilnt)
Tatl1t)' Sanchtone (rnWc Eocetle)
0elmat Pormi:IIOII ll'l"lidOlf 1:oce,e)
Sallllago Fonttali:ln (tl'tdOle Eocene)
lJncMdild Eooenetodl.l In lhe dllhole •rea (&c.ne)
Ml!IHetllf'l'lel'llaty •f'ld ""8!8\'0lc.nic ,c,cQ, unchlded {Mtteol!oiej
MINVOlclanleclk•(~
Mlllllgn!Necockl (Maa.tdc)
Q.iaitr.Jlll eno quaru. ~ (Mmonl11:)
FIGURE 4 -GEOLOGIC MAP
PARTNER
REVISED BORING LOGS
SURFACE COVER: General discription with thickness to the inch, ex. Topsoil, Concrete, Asphalt, etc,
FILL: General description with thickness to the 0.5 feet. Ex. Roots, Debris, Processed Materials (Pea Gravel, etc.)
NATIVE GEOLOGIC MATERIAL: Deposit type, 1.Color, 2.moisture, 3.density, 4.SOIL TYPE, other notes - Thickness to 0.5 feet
1. Color - Generalized
Light Brown (usually indicates dry soil, rock, caliche)
Brown (usually indicates moist soil)
Dark Brown (moist to wet soil, organics, clays)
Reddish (or other bright colors) Brown (moist, indicates some soil development/or residual soil)
Greyish Brown (Marine, sub groundwater - not the same as light brown above)
Mottled (brown and gray, indicates groundwater fluctuations)
2. Moisture
dry - only use for wind-blown silts in the desert
damp - soil with little moisture content
moist - near optimum, has some cohesion and stickyness
wet - beyond the plastic limit for clayey soils, and feels wet to the touch for non clays
saturated - Soil below the groundwater table, sampler is wet on outside
3A. Relative Density for Granular Soils 3B. Consistency of Fine-Grained Cohesive Soils
Ring SPT Consistnecy SPT
0-7 0-4 very soft 0-2
7-14 4-10 soft 2-4
14-28 10-30 medium stiff 4-8
28-100 30-50 stiff 8-15
100+Over 50 very stiff 15-30
hard Over 30
4. Classification
Determine percent Gravel (Material larger than the No. 4 Sieve)
Determine percent fines (Material passing the No. 200 Sieve)
Determine percent sand (Passing the No. 4 and retained on the No. 200 Sieve)
Determine if clayey (make soil moist, if it easily roll into a snake it is clayey)
Coarse Grained Soils (Less than 50% Passing the No. 200 Sieve)
GP SP Mostly sand and gravel, with less than 5 % fines sandy GRAVEL SAND
GP-GM SP-SM Mostly sand and gravel 5-12% fines, non-clayey sandy GRAVEL with silt SAND with Silt
GP-GC SP-SC Mostly sand and gravel 5-12% fines, clayey sandy GRAVEL with clay SAND with clay
GC SC Mostly sand and gravel >12% fines clayey clayey GRAVEL clayey SAND
GM SM Mostly sand and gravel >12% fines non-clayey silty GRAVEL silty SAND
Fine Grained Soils (50% or more passes the No. 200 Sieve)
ML Soft, non clayey SILT with sand
MH Very rare, holds a lot of water, and is pliable with very low strength high plasticity SILT
CL If sandy can be hard when dry, will be stiff/plastic when wet CLAY with sand/silt
CH Hard and resiliant when dry, very strong/sticky when wet (may have sand in it)FAT CLAY
H = Liquid limit over 50%, L - LL under 50%
C = Clay
M = Silt
Samplers
S = Standard split spoon (SPT)
R = Modified ring
Bulk = Excavation spoils
ST = Shelby tube
C = Rock core
BORING LOG KEY - EXPLANATION OF TERMS
Over 2.0
Relative Density
very loose
loose
dense
very dense
medium dense
Undrained Shear Strength, tsf
less than 0.125
0.125 - 0.25
0.25 - 0.50
0.50 - 1.0
1.0 - 2.0
Geotechnical Report
Project No. 21-337267.5 A - 1
Boring Number: Bl Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Asphalt
0.5
1
1.5
2 s 11 SM FILL: Light brown, damp, medium dense, silty SAND
2.5 (Moisture Content: 24.1%, Fines: 40.2%)
3
3.5
4
4.5
5 R 31 (Dry Density: 96.2 pcf, Moisture Content: 25.6%)
5.5
6
6.5
7 s 20
7.5
8
8.5
9 -----------------------------------------------------------9.5
10 R 44 SC NATIVE: Mottled light brown and orange brown, damp, dense, clayey SAND
10.5 (Dry Density: 100.3 pcf, Moisture Content: 20.2%)
11
11.5
12
12.5
13
13.5
14
14.5
15 s 24 light brown to white, medium dense, clayey SAND; some burnt black wood debris
15.5
16
16.5
17
17.5
18
18.5
19
19.5
20 I s 13 light to dark brown
Geotechnlcal Report
Project No. 21-337267.5
A -2
Boring Number: Bl Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
20 s 13 SC light brown to brown, medium dense, clayey SAND; some burnt black wood debris
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Gaotechnlcal Report
Project No. 21-337267.5
A -3
Boring Number: 82 Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Grass and topsoil
0.5
1
1.5
2 R 36 SC Fill: Brown, damp, medium dense, clayey SAND; fine sand grains
2.5 (Dry Density: 89.9 pd, Moisture Content: 14.9%)
3
3.5
4
4.5
5 s 17
5.5
6
6.5
7 R 39 (Dry Densrty: 90.9 pd, Moisture Content: 20.6%)
7.5
8
8.5
9 -----------------------------------------------------------9.5
10 s 11 SC Native: Mottled light brown and orange brown, damp, dense, clayey SAND
10.5
11
11.5
12
12.5
13 -----------------------------------------------------------13.5
14
14.5
15 s 28 Cl NATIVE: 'Dark brown to gray, damp, very stiff, sandy CLAY
15.5
16
16.5
17
17.5
18 -----------------------------------------------------------18.5
19
19.5
20 I s 34 ML Dark brown to gray, damp, hard, sandy SILT
o.otechnlcal Report
Project No. 21-337267.5
A -4
Boring Number: 82 Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
20 s 34 ML Dark brown to gray, damp, hard, sandy SILT
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Gaotechnlcal Report
Project No. 21-337267.5
A -5
Boring Number: 83 Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Grass and topsoil
0.5
1
1.5
2 R 25 SM FILL: Brown, damp, medium dense, silty SAND
2.5 (Dry Density: 87.1 pd, Moisture Content: 21.2%)
3
3.5
4
4.5
5 s 19
5.5
6
6.5
7 R 30 light brown
7.5 (Dry Density: 90.2 pd, Moisture Content: 28.1%)
8
8.5
9 -----------------------------------------------------------9.5
10 s 17 SC NATIVE: Mottled light brown and orange brown, damp, medium dense, clayey SAND
10.5
11
11.5
12
12.5 -----------------------------------------------------------13
13.5
14
14.5
15 s 28 Cl Mottled dark brown, white, and orange, damp, hard, sandy CLAY
15.5
16
16.5
17
17.5
18 -----------------------------------------------------------18.5
19
19.5
20 I s 34 SM light brown, damp, dense, silty SAND
Geotechnlcal Report
Project No. 21-337267.5
A-6
Boring Number: 83 Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
20 s 34 SM light brown, damp, dense, silty SAND
20.5
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Gaotechnlcal Report
Project No. 21-337267.5
A -7
Boring Number: 84 Boring Log Page 1 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Grass and topsoil
0.5
1
1.5
2 s 11 SM Fill : Brown, damp, medium dense, silty SAND
2.5
3
3.5
4
4.5
5 R 32 Hard
5.5 (Dry Density: 93.9 pcf, Moisture Content: 26.9%)
6
6.5
7 s 17 light brown
7.5
8
8.5
9 -----------------------------------------------------------9.5
10 R 44 SC NATIVE: Mottled light brown and orange brown, damp, dense, clayey SAND
10.5 (Dry Density: 99.6 pcf, Moisture Content: 20.8%)
11
11.5
12
12.5
13 -----------------------------------------------------------13.5
14
14.5
15 s 33 Cl Mottled dark brown, white, and orange, damp, hard, sandy CLAY
15.5
16
16.5
17
17.5
18 -----------------------------------------------------------18.5
19
19.5
20 I s 23 SM light brown, damp, medium dense, silty SAND
Geotechnlcal Report
Project No. 21-337267.5
A -8
Boring Number: 84 Boring Log Page 2 of 2
Location: See Figure 2 Date Started: 7/25/2022
Site Address: 193S Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, CA 92008 Depth to Groundwater: N/A
Project Number: 21-337267.5 Field Technician: SH
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon Sampler 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
20 s 23 SM light brown, damp, medium dense, silty SAND
20.S
21
21.5 Boring terminated at 21.5 feet below existing surface
22 Groundwater not encountered
22.5 Boring backfilled with soil cuttings upon completion
23
23.5
24
24.5
25
25.5
26
26.5
27
27.5
28
28.5
29
29.5
30
30.5
31
31.5
32
32.5
33
33.5
34
34.5
35
35.5
36
36.5
37
37.5
38
38.5
39
39.5
40
Gaotechnlcal Report
Project No. 21-337267.5
A -9
Boring Number: HAl Boring Log Page 1 of 1
Location: Western Interior of Building Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, California 92008 Depth to Groundwater: NA
Project Number: 21-337267.5 Field Technician: WVA
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Concrete
0.5
1
1.5
2 I G SC FILL: Brown, damp, clayey SAND; with gravel
2.5
3
3.5
4
4.5
5 I G
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15
15.5
16
16.5
17
17.5
18
18.5
19
19.5
20
Gaotechnlcal Report
Project No. 20-290825.4
light brown
Boring terminated at 5 feet bgs,
Backfilled with excess soil cuttings
Patched with concrete
A -10
Boring Number: HA2 Boring Log Page 1 of 1
Location: Western Interior of Building Date Started: 7/25/2022
Site Address: 1935 Camino Vida Roble Date Completed: 7/25/2022
Carlsbad, California 92008 Depth to Groundwater: NA
Project Number: 21-337267.5 Field Technician: WVA
Drill Rig Type: CME-75 Partner Engineering and Science
Sampling Equipment: Cal Mod/ Split Spoon 2154 Torrance Blvd., Suite 201
Borehole Diameter: 8" Torrance, CA 90501
Depth, FT Sample N-Value uses Description
0 SURFACE COVER: Concrete
0.5
1
1.5
2 I G SC Fill: Brown, damp, clayey SAND; with gravel
2.5
3
3.5
4
4.5
5 I G (Moisture Content: 17.3%, LL: 36, Pl: 17, Fines: 26.4%)
5.5 Boring terminated at 5 feet bgs.
6 Backfilled with excess soil cuttings.
6.5 Patched with concrete
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15
15.5
16
16.5
17
17.5
18
18.5
19
19.5
20
Gaotechnlcal Report
Project No. 20-290825.4
A -11
ADDITIONAL LAB TESTING
Moisture and Density Data
Soil Sample Dry Density Moisture Content (%)
81 @ 5 feet 96.2
81 @ 10 feet 100.3
82@ 2.5 feet 89.9
82@ 7 feet 90.9
83@ 2.5 feet 87.1
83@ 7 feet 90.2
84@ 2.5 feet 93.9
84@ 10 feet 99.6
INDEX TEST DATA
Boring I Depth, ft I Plast icity I Plastic
Index Limit
Liquid
Limit
Moisture
Content(%)
Geotechnical Report
Project No. 21-337267.5
August 24, 2023
Page 8-i
25.6
20.2
14.9
20.6
21.2
28.1
26.9
20.8
Percent Passing the
No. 200 Sieve
26.4
40.2
PARTNER
INFILTRATION FORMS
Table D.2-3
Form I-8
2 x 0.25 = 0.5
2 x 0.25 = 0.5
2 x 0.25 = 0.5
1 x 0.25 = 0.25
1.75
-.. -·-• .. •
Suitability
Assessment
(A)
Design
(B)
Appen dix D : Geotechnical E ngineer Analysis
T able D .2-3: D etermination of Safety Factor
J7° -i"" -... ,riffl .. h .. tl ..... ]w.,-,n, ,,. .. ~
---.,-=;. -... , ..... .., -·
........,
11.\.' .• ,._,_ ..... "' ... .. ... IJ.'I"
Infiltration Testing .Method 0.25
Soil Texture Class 0.25 Refer to
Soil Variability 0.25 Table D.2-4
Depth to Groundwater/Obstruction 0.25
Suitability Assessment Safety Factor, S,., = Lp
Pretreatment 0.50
Resiliency 0.25 Refer to
TableD.2-4
Compaction 0.25
Design Safety Factor, SB = Lp
Safety Factor, S = SA x SB
(Must be always greater than or equal to 2)
The geotecbnical engineer should reference Table D.2-4 below in order to determine appropriate
factor values for use in the table above. The values in the table below are subjective in nature and
the geotechnical engineer may use professional discretion in how the points are assigned.
D -12 Jan. 2023
-.. --• •. .. .
Infiltration
T esting
Method
Soil Texture
Class
Soil
Variability
D epth to
Groundwater/
Obstn1ction
Pretreatment
Resiliency
Compaction
Appendix D : Geotechnical Engineer Analysis
Table D.2-4: Guidance for Determining Individual Factor Values
___ .,_ -----i"-• -J:~~-.. • . , .. ..... ,. ... .. . ,. . .. . ,.. -.. ..... -.... ... m. ..... -• ··••■-----,ijJ ,~·.I.I.JI■ IIL_..,. -.,._,.. .-... -------
At least 4 tests within Bl\IP
At least 2 tests of any kind footprint, OR Large/Small
Any within 50' of Bl\IP. Scale Pilot Infiltration Testing
over at least 5% of Bl\IP
footprint.
Unknown , Silty, Granular/Slightly Loamy or Clayey Loamy
Unknown or
High l\Ioderately H omogeneous Significantly Homogeneous
<5' below Bl\fP 5-15' below Bl\IP >15' below Bl\-IP
Provides good pretreatment Provides excellent pretreatment
None/Minimal OR does not receive significant OR only receives runoff from
runoff from unpaved areas rooftops and road surfaces.
Includes underdrain /backup Includes underdrain/backup
None/Minimal drainage tl1at ensures ponding drainage AND supports easy
draws down in <96 hours restoration of impacted
infiltration rates.
l\Ioderate Low Likelihood Very Low Likelihood Likelihood
D-13 Jan. 2023
X
Results of the Infiltration Tests conducted on site resulted in rates ranging from 0.03
to 0.13, well below the 0.5 threshold
Appendix I: Forms and Checklists
Part 1-Full Infiltration Feasibility Screening Criteria
Would infiltration of the full design volume be feasible from a physical perspective without any undesirable
consequences that cannot be reasonably mitigated?
Criteria 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 must be based on a comprehensive evaluation of
the factors presented in Appendix C.2 and Appendix D .
Provide basis:
Yes No
Snmroaciz,, findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability.
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 must be based on a comprehensive evaluation of the factors
presented in Appendix C.2.
Provide basis:
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability.
1-3 Febniary 26, 2016
No
Appendix I: Forms and Checklists
Criteria
3
.-•
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 must be based on a comprehensive evaluation of the factors
presented .i.t1 Appendix C.3.
Provide basis:
Yes No
Summarize findings of studies; provide reference to smdies, 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? TI1e response to this
Screening Question must be based on a comprehensive evaluation of
the factors presented .ill Appendix C.3.
Provide basis:
Summarize find.lllgs of studies; provide reference to smdies, calculations, maps, data sources, etc. Provide narrative
discussion of smdy / data source applicability.
Part 1
Result
*
If all answers to rows l -4 are "Yes" a full lllfiltration design is potentially feasible. The
feasibility screening category is Full Infiltration
If any answer from row 1-4 is "No", lllfiltration may be possible to some extent but
would not generally be feasible or desirable to achieve a "full lllfiltration" design.
Proceed to Part 2
>!<To be completed using gathered site lllformation and best professional judgment considering the definition of MEP iri
the i\IS4 Permit. Additional testing a11d/or studies may be required by Agency/Jurisdictions to substantiate findings
1-4 Febniary 26, 2016
X
Results of the Infiltration Tests conducted on site resulted in rates ranging from 0.03
to 0.13, once the factor of safety is applied rates would be well below the minimum
0.3 inches per hour recommend by the Regional Water Quality Control Board.
Appendix I: Forms and Checklists
Part 2 -Partial lnfiltration vs. No Infiltration Feasibility Screening Criteria
Would infiltration of water m 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 must be based on a comprehensive evaluation of the factors
presented in Appendi.." C.2 and Appendix D .
Provide basis:
Yes No
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability and why it was not feasible to mitigate low infiltration rates.
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 must be based on a comprehensive evaluation of the factors
presented in Appendix C.2.
Provide basis:
Summarize findings of studies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of study/ data source applicability and why it was not feasible to mitigate low infiltration rates.
1-5 Febniary 26, 2016
No
Infiltration
Criteria
7
Appendix I: Forms and Checklists
.-
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 must be based on a
comprehensive evaluation of the factors presented in Appendix C.3.
Yes No
Provide basis:
Summarize findings of studies; provide reference to smdies, calculations, maps, data sources, etc. Pronde narrative
discussion of study/data source applicability and why it was not feasible to mitigate low infiltration rates.
8
Can in.filtration be allowed without violating downstream water
rights? The response to this Screening Question must be based on a
comprehensive evaluation of the factors presented in Appendix C.3.
Provide basis:
Summarize findings of srudies; provide reference to studies, calculations, maps, data sources, etc. Provide narrative
discussion of smdy / data source applicability and why it was not feasible to mitigate low infiltration rates.
Part 2
Result*
If all answers from row 1-4 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. TI1e feasibility screening category is No Infiltration.
>i<'f o be completed using gathered site information and best professional judgment considering the definition of i\IEP in
the .i\IS4 Permit. Additional testing and/ or studies may be required by Agency/J urisdictions to substantiate findings
1-6 Febniary 26, 2016
CITY COMMENTS
I •
Geotechnical & Environmental Sciences Consultants
July 10, 2023
Project No. 109343020
Ms. Jessica Nishiura, PE
Hunsaker & Associates San Diego, Inc.
9707 Waples Street
San Diego, California 92121
Subject: Third-Party Geotechnical Review
Solvent Tank Farm and Interior Platforms
1935 Camino Vida Roble
Carlsbad, California
Dear Ms. Nishiura:
At your request, we have prepared this letter providing our review comments to the referenced
geotechnical report prepared by Partner dated September 18, 2022. Our comments regarding the
geotechnical report include the following:
Comment 1: The Geotechnical Consultant should review the project grading and foundation plans
and provide any additional geotechnical recommendations, as appropriate, and indicate if the plans
have been prepared in accordance with the geotechnical recommendations provided in the
referenced geotechnical report (Partner, 2022).
Comment 2: The Executive Summary and various other sections of the referenced geotechnical
report (Partner, 2022) describes a 50-foot high slope that descends to the northwest. The
Geotechnical Consultant should clarify if the slope descends to the northwest or southwest and
at what inclinations the existing slopes are at.
Comment 3: Per the grading plans prepared by kpff, cuts more than 5 feet are anticipated to
occur as part of the construction of the retaining wall at the eastern side of the property. The
Geotechnical Consultant should provide recommendations for the Occupational Safety and Health
Administration (OSHA) soil classifications and temporary slope configurations for excavations
performed onsite.
Comment 4: The Executive Summary and various other sections in the referenced geotechnical
report (Partner, 2022), including the borings logs, indicate that native soils were encountered
beneath the surface cover materials. However, based on our review of previous as-built site grading
plans (City of Carlsbad, 1990) that are readily available on the City of Carlsbad's online portal for
public records (https://records.carlsbadca.gov/WebLink/Welcome.aspx?cr=1) indicates that the
northern portion of the site consists of cut materials while the southern portion of the site includes
fills up to approximately 35 feet or more. The Geotechnical Consultant should review the available
grading plans and reports available online and update their report accordingly.
5710 Ruffin Road I San Diego, Cal ifornia 92123 Ip. 858.576.1000 I www.ninyoandmoore.com
Comment 5: In the "Project Data" table under Section 2.2 "Assumed Construction" of the referenced
geotechnical report (Partner, 2022), the sentence under the "Type of Construction" looks to be cut short.
The Geotechnical Consultant should clarify this project description.
Comment 6: Section 2.3 "References" in the referenced geotechnical report (Partner, 2022) mentions
of the usage of a geologic map for an area in San Bernardino County. The Geotechnical Consultant
should update this reference.
Comment 7: Section 4.2 "Groundwater'' in the referenced geotechnical report (Partner, 2022) provides
discussion about the historical high groundwater being at a depth of 5 feet below the groundwater
surface. Since the site is described as being· at the top of a 50-foot high slope, the Geotechnical
Consultant should consider further expanding on the groundwater discussion to incorporate the sloping
aspects of the site boundaries.
Comment 8: Section 4.4 "Infiltration Tests" in the referenced geotechnical report (Partner, 2022)
indicates that percolation testing was performed in accordance with the County of San Diego standards.
The Geotechnical Consultant should indicate if the infiltration testing was performed in accordance with
the 2023 City of Carlsbad BMP Design Manual and provide any additional information as indicated in
Appendix D of the manual.
Comment 9: On Page 11 of the referenced geotechnical report (Partner, 2022), under "On-Grade
Construction Considerations," there is discussion for the scarification of the subgrade soils to a depth of
24 inches. The Geotechnical Consultant should clarify if this recommendations is intended to read as an
overexcavation or a scarification process.
Comment 10: On Page 12 of the referenced geotechnical report (Partner, 2022), under "Soil Reuse
Considerations," there is discussion regarding the reuse of low to non-plastic soils with a plasticity index
(Pl) less than 15. However, other sections of the report reference low to non-plastic soils as consisting
of a Pl of less than 20. The Geotechnical Consultant should clarify which plasticity index is appropriate.
Comment 11: On Page 12 of the referenced geotechnical report (Partner, 2022), under "Soil Reuse
Considerations," there are recommendations for engineered fill to be placed at a relative compaction of
95 percent as evaluated by ASTM International (ASTM) D 1557. However, Appendix C recommends the
placement of engineered fill at a relative compaction of 95 percent as evaluated by ASTM D 698 or 90
percent of ASTM D1557. The Geotechnical Consultant should clarify which recommendation is intended.
Comment 12: The "Prepared Subgrade Parameters" table under Section 5.2 "Geotechnical Parameters"
of the referenced geotechnical report (Partner, 2022) provides recommendations for the coefficients of
friction and bearing values for various foundation types. Since there is no direct shear or other strength
test data presented in the report, Geotechnical Consultant should provide discussion as to how these
design parameters were developed.
Comment 13: The "Prepared Subgrade Parameters" table under Section 5.2 "Geotechnical Parameters"
of the referenced geotechnical report (Partner, 2022) provides estimates for the settlements associated
with various foundation types. As noted earlier, as-built site grading plans (City of Carlsbad, 1990)
indicate the presence of fills up to approximately 35 feet deep or more. Accordingly, the native soils
encountered may be existing fills. The referenced geotechnical report (Partner, 2022) does not include
discussion or background information regarding the as-graded compaction levels of the existing fills or
present any consolidation test results. The Geotechnical Consultant should provide backup information
and further justification for the estimated settlements.
Ninyo & Moore I 1935 Camino Vida Roble, Carlsbad, California I 109343020 I July 10, 2023 2
Comment 14: The "Prepared Subgrade Parameters" table under Section 5.2 "Geotechnical
Parameters" of the referenced geotechnical report (Partner, 2022) provides estimates for the
differential settlements associated with various foundation types. The Geotechnical Consultant
should indicate over what horizontal distance are the estimated differential settlements to occur over.
Comment 15: The "Paving Structural Sections" table on Page 15 of the referenced geotechnical
report (Partner, 2022) recommends a concrete pavement section thickness of 3 inches for light duty
parking areas. The Geotechnical Consultant should provide backup information and further
justification for this recommended pavement thickness.
Comment 16: The Geotechnical Consultant should provide an updated geotechnical map/plot plan
utilizing the latest grading plan for the project to clearly show the lateral limits ofthe recommended
remedial grading.
Comment 17: Per the City of Carlsbad's (1993) guidelines, the Geotechnical Consultant is to
provide recommendations for the thickness and reinforcing of exterior concrete flatwork.
Comment 18: The Consultant should provide a statement regarding the impact of the proposed
grading and construction on adjacent properties and improvements.
We appreciate the opportunity to be of service.
Respectfully submitted,
NINYO & MOORE
J/in~;GE
Principal Engineer
WRM/JTK/mp
Attachment: References
Ninyo & Moore I 1935 Camino Vida Roble, Carlsbad, California I 109343020 I July 10, 2023 3
REFERENCES
City of Carlsbad, 1990, As-Built Grading Plans For: Carlsbad Tract No. 81 -46, Airport Business
Center Unit No. 1, Drawing No. 224-1A, Sheets 1 through 11: dated March 6.
City of Carlsbad, 1993, Technical Guidelines For Geotechnical Reports: dated January.
City of Carlsbad, 2023, BMP Design Manual, Appendix D: dated January 11.
kpff, First Submittal: Grading Plans for 935 Camino Vida Roble (Kinovate Production Facility Tl):
undated.
Partner, 2022, Geotechnical Report, Solvent Tank Farm and Interior Platforms -Carlsbad Airport,
1935 Camino Vida Roble, Carlsbad, California , Partner Project No. 21-337276.5: dated
September 18.
Ninyo & Moore I 1935 Camino Vida Roble, Carlsbad, California I 109343020 I July 10, 2023 4
GEOTECHNICAL REPORT ADDENDUM 2
PARTNER
800-419-4923 www.PARTNEResi.com
October 22, 2023
Greg Holmquist
Nitto Denko Technical Group
501 Via Del Monte
Oceanside, California 92058
Subject: Geotechnical Report Addendum
Solvent Tank Farm and Interior Platforms – Carlsbad Airport
1935 Camino Vida Roble
Carlsbad, California 92008
Partner Project No. 21-337267.5
Dear Mr. Greg Holmquist:
Partner Assessment Corporation (Partner) performed a geotechnical investigation for the proposed Solvent
Tank Farm and Interior Platforms to be located at 1935 Camino Vida Roble in Carlsbad, California, and
summarized the results in a report dated September 18, 2022. The City of Carlsbad (The City) requested a
third-party review of our report by Ninyo & Moore Geotechnical & Environmental Sciences Consultants
(N&M). A list of review comments was provided in their letter dated July 10, 2023 (N&M Project Number
No. 109343020) and responded to in our response to comments letter dated August 10, 2023. This
addendum serves to provide recommendations for the proposed permeable pavers and revise the
pavement recommendations that were provided in our Geotechnical Report (2022).
Permeable Paver Recommendations
It is our understanding that permeable pavers will be installed around the building footprint and will only
be subjected to pedestrian traffic. We recommend that permeable pavers be constructed per the
manufacturer’s recommendations. The soil stratum encountered during our geotechnical exploration
consisted of silty sand atop sandy clay followed by lean clay. No groundwater was encountered during our
geotechnical investigation. Based on the soils encountered and the provided permeable paver plan, we do
not believe the limited amount of water being infiltrated will cause any adverse effect to the adjacent
structures, therefor an impermeable lining is not recommended.
Pavement Design and Construction Recommendations
In our experience we recommend that multiple different pavement sections be considered for the project
for economic and performance reasons. For drive-thru lanes and trash enclosures we recommend that
thickened reinforced concrete pavement be utilized. For heavily used and ADA parking spaces, etc., we
recommend the use of thinner reinforced concrete pavement. We understand that asphalt is not planned,
however, if plans change, we recommend a heavy-duty asphalt pavement section, and thinner sections can
be used in the parking field if any. We recommend concrete pavements consist of local DOT, or otherwise
jurisdictionally approved mixes, and that paving cross slopes, curbs, and other features conform to the
applicable local standard specifications and details.
The required pavement and base thicknesses will depend on the expected wheel loads, traffic index (TI),
and the R-value of the subgrade soils. We have conservatively assumed an R-value of 35 for the design of
PARTNER
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