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Home My WebLink AboutSDP 15-22; QUARRY CREEK PA R-2; STORM WATER MANAGEMENT PLAN; 2016-02-05,.., ___________________________________ _ ... -.. - -... - --- -.. -.. ------------------ - ADDENDUM TO THE MASTER SWMP FOR QUARRY CREEK STORM WATER MANAGEMENT PLAN FOR QUARRY CREEK PLANNING AREA R-1/R-2 City of Carlsbad, CA Project No. SDP 15-17 & SDP15-22 SWMP 15-22 Related Project ID: MS 15-13 PREPARED FOR: Lennar Multifamily Communities 95 Enterprise, Suite 200 Aliso Viejo, CA 92656 BB&D~ PLANNINC-, ENGINEERING SURVEYING 3990 RUFFIN ROAD, SUITE 120 SAN DIEGO, CA 92123 858-560-1141 JOB NO. 71820.65/71920.60 February 5, 2016 City of Carlsbad FEB (i 9 ZO\S Planning Division - -... ---... ---------------- --- TABLE OF CONTENTS 1.0 2.0 3.0 4.0 5.0 6.0 Scope of Report 1.1 Declaration of Responsible Charge Summary of Project Information Pre-Project Site Conditions and Drainage Patterns Narrative 3.1 Site Development Constraints Proposed Site Development and Drainage Patterns Narrative 4.1 Site Development Opportunities Sources of Pollutants from the Existing Site Narrative Project Hydrologic Location 7.0 Identification of 303(d) Impaired Receiving Waters 8.0 9.0 Identification of Pollutants Associated with Priority Project Category Identification of Pollutants of Concern 10.0 Hydromodification Management Plan (HMP) Applicability Determination 11.0 Summary of HMP Compliance Approach 12.0 Permanent Source Control Best Management Practices (BMPs) 13.0 Identification of BMPs Applicable to Individual Priority Project Categories 14.0 Implementation of Site Design Low Impact Development (LID) Practices 15.0 Relative Effectiveness of Project Treatment Facilities and Integrated Management • Practices (IMPs) -16.0 Comparison of Water Quality Areas -• 17.0 Summary and Conclusion Narrative ------ QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page i SB&OINC. .. 11111 ----------- ------------------ ----- 18.0 Figures Vicinity Map Basin BB-1 Exhibit Proposed R-1/R-2 SWMP/ Exhibit (map pocket) 19.0 Attachments City of Carlsbad Storm Water Standards Questionnaire Master Drainage Area Exhibit (PDC) Summary of Drainage & Impervious Areas (PDC) Geo technical Study reference Permanent BMP Certification Form (see Project Design Consultants [PDC] master report) QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page ii SB&OINC. ------------------------- ---------- 1.0 Scope of Report A Master report, "Storm Water Management Plan Quarry Creek," dated March 19, 2015, was prepared for the Quarry Creek project by Project Design Consultants (PDC). The PDC master report summarizes the storm water requirements for the entire Quarry Creek project, including combination (bioretention, water quality and detention) basins "BB-1", "BB 3-2A", and "BB 3- 2B" are located south of the R-1 and R-2 Planning Areas. Runoff from the R-1 and R-2 sites are tributary to the one or more combination basins and are not cleanly delineated for comparison purposes. Further, the PDC master report details the design and modeling of the bioretention basins using continuous simulation modeling (SDHM), rather than the BMP sizing tables. A copy of the Basin Area Exhibit from the Master SWMP Report is included in the Attachments Section. This report is limited to documenting the following at the Planning Area R-1 & R-2 site: A) Site Design B) Source Control C) Tributary area and impervious area, including comparisons to those used in the PDC report (R-1 & R-2 combined). D) Compliance and consistency with the assumptions and design parameters used in the PDC master report (R-1 & R-2 combined). 1.1 Declaration of Responsible Charge This Storm Water Management Plan (SWMP) has been prepared under the direction of the following Professional Civil Engineer. The Professional Civil Engineer (Engineer) attests to the technical information contained herein, and to the engineering data upon which the following design, recommendations, conclusions and decisions are based. The selection, sizing, and design of the storm water treatment and other control measures in this report meet the requirements of the Regional Water Quality Control Board Order R9-2007-0001 and subsequent amendments. QUARRY CREEK Planning Areas R-1 & R-2 SB&O Inc. Company QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 1 2- SB&O INC. -----... ---... --------------------.. ------- 2.0 Summary of Project Information Item Project Name Application Number(s) Project Address Assessor Parcel Number(s) Total Project Area Proposed Project Description and Land Use Applicable Priority Development Project Categories Redevelopment Project that Creates or Replaces 5,000 square feet of Impervious Surface Project Hydrologic Unit Watershed Project Hydrologic Soil Group Number of Discharge Locations Required to Implement HMP Number of HMP Compliance Points Applicant Contact QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 2 Project Information Quarry Creek Planning Area R-1 & R-2 SOP 15-17 (R-1) & SOP 15-22 (R-2) East of El Saito Falls Rd., South ofHaymar Drive Portion 167-040-21 R-1 3.22 AC/ 140,398 SF R-2 15.40 AC/ 670,847 SF Multifamily Residential 1::8:1 Housing Development of 10 or more dwelling units D Commercial Development of one acre and greater D Heavy Industry of one acre and greater D Automotive Repair Shop D Restaurant 1::8:1 Hillside Development greater than 5,000 square feet D Water Quality Environmentally Sensitive Area (WQESA) D Parking Lot 1::8:1 Street, Highways, and Freeways D Retail Gasoline Outlets 1::8:1 Land Disturbance greater than one acre D Increases or D Increases or 1::8:1 Not Replaces >50% of Replaces <50% of Applicable Pre-Project Imp. Pre-Project Imp. Surface Surface Carlsbad Hydrologic Unit □A l □B l □c jl::8:lo 3 Downstream WQ/Detention Basins 1::8:1 Yes J 0No NIA (See PDC Master Report for Details) Jack Robson (858) 458-9700 irobson@cornerstonecommunities.com SB&O INC. -- .. 111111 ---- - - -- -------------------- 3.0 Pre-Project Site Conditions and Drainage Patterns Narrative The Planning Area R-1 & R-2 sites are part of the larger master plan Quarry Creek development. The project is located in the City of Carlsbad (City), but is bordered to the east by the City of Oceanside. The project is situated west of College Boulevard, east of Interstate 5, and south of Haymar Drive. The R-1 and R-2 Planning Areas are located in the northeastern portion of the Quarry Creek development. R-1 is part of the initial phase of the Quarry Creek project and includes preparation of the large sheet graded pads, and construction of public roads, public utilities, and the LID facilities required for both current and future phases of the project. The total tributary area to basin's BBl, BB2-3A, and BB2-3B is approximately 27.58 acres, expected to be high density residential as well as streets, according to the PDC report. See Section 16 for a comparison of tributary and impervious areas. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 3 SB&O INC. 3.1 Site Development Constraints Applicable Site Development Constraints D Limited Available Hydraulic Head ~ Impermeable Soils D High Groundwater D Contaminated Soils D Geotechnical Instability D Perimeter Conditions D High Intensity Land Use D Heavy Pedestrian Traffic D Heavy Vehicular Traffic D Restricted Right-of-Way D Existing Easements D Inadequate Down-Stream Drainage Infrastructure D Public Safety Concerns ~ Other: Master planned storm drain & water quality Comments: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 4 SB&O INC. .. ... ... --.... ... .. .. .. .. .. .. .. --... --.. - 1111111 ------------ 4.0 Proposed Site Development and Drainage Patterns Narrative In order to verify the sizing of the basins, this report will compare combined areas from R-1, R- 2, and offsite portions. This report compares the total areas discharging into each basin (BB-2- 3A, BB2-3B, and BB-1). The areas were designed to be consistent with the total areas assumed in the PDC report which include offsite areas . The R-1 area is the multi-family residential development. A total of 64 units will be constructed, consisting of various attached product types and both 2 and 3 story buildings The R-2 area will also be included in this report with a total of 278 units . R-1 is approximately 3.22 acres with a net developable area of 3.17 acres and R-2 is approximately 15.40 acres, with a net developable area of approximately 13.63 acres. This yields a net project density of approximately 20 dwelling units per acre for both projects, which corresponds to High Density Residential (HDR) per Table 3-1 "Runoff coefficients for Urban Areas" of the San Diego County Hydrology Manual . The development of the R-1 and R-2 Planning Area are predominately attached multifamily buildings with surface parking and private storm drain systems. The projects will route runoff through the onsite private drainage systems to discharge to the various bio-retention basin BB-1, BB2-3A, and BB2-3B. See Section 16 for a comparison of impervious and tributary areas. The limits of basin BB-1 were revised, and the surface area is slightly larger (approximately 9%) than the previous basin . Refer to Exhibit "A" in the Section 18 Figures for the revised BB-1 basin and the bottom area comparison. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Pages SB&O INC. 4.1 Site Development Opportunities Applicable Site Development Opportunities [8J Adequate Available Hydraulic Head D Permeable Soils D Groundwater Separation D Geotechnical Stability D Perimeter Conditions D Existing Natural Areas D Undevelopable Areas [8J Adequate Down Stream Drainage Infrastructure [8J Other: Master Planned Water Quality, Hydromodification & Detention Facilities Comments: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 6 SB&O INC. ----------------- --- - - ----.. -.. 5.0 Sources of Pollutants from the Existing Site Narrative There are no known legacy pollutants on this site. A legacy pollutant is defined as an existing pollutant remaining from past land uses. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 7 SB&O INC. 6.0 Project Hydrologic Location Hydrologic Unit Hydrologic Area Carlsbad 904.00 Buena Vista Creek 904.20 QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 8 Hydrologic Sub-Area El Saito 904.21 SB&O INC. 7.0 Identification of 303(d) Impaired Receiving Waters Receiving Water ~ Buena Vista Creek ~ Buena Vista Lagoon QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 9 Pollutant(s) Causing Impairment to 303(d) Receivin2 Water Selenium Sediment Toxicity Nutrients Indicator Bacteria Sedimentation/ Siltation SB&O INC. 8.0 Identification of Pollutants Associated with Priority Project Category Priority Project Category Detached Residential □ Development Attached Residential ~ Development D Commercial Development □ Heavy Industry or Industrial Development QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 10 General Pollutant Categories Sediment Nutrients Trash & Debris Oxygen Demanding Substances Oil & Grease Bacteria & Viruses Pesticides Sediment Nutrients Trash & Debris Oxygen Demanding Substances (if landscape exists on-site) Oil & Grease (if uncovered parking areas exist on-site) Bacteria & Viruses Pesticides Sediment (if landscape exists on-site) Nutrients (if landscape exists on-site) Heavy Metals Organic Compounds (if uncovered parking areas exist on-site) Trash & Debris Oxygen Demanding Substances (includes solvents) Oil & Grease Bacteria & Viruses (if land use includes food or animal waste products) Pesticides (includes solvents) Sediment Heavy Metals Organic Compounds Trash & Debris Oxygen Demanding Substances Oil & Grease SB&O INC. 8.0 Identification of Pollutants Associated with Priority Project Category ( continued) Priority Project Categories D Automotive Repair Shop D Restaurants D Hillside Development ~ Parking Lots D Retail Gasoline Outlets ~ Streets, Highways & Freeways QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 11 General Pollutant Categories Heavy Metals Organic Compounds (includes petroleum hydrocarbons and solvents) Trash & Debris Oil & Grease Trash & Debris Oxygen Demanding Substances Oil & Grease Bacteria & Viruses Pesticides (if landscape exists on-site) Sediments Nutrients Trash & Debris Oxygen Demanding Substances Oil & Grease Pesticides Sediments (if landscape exists on-site) Nutrients (if landscape exists on-site) Heavy Metals Trash & Debris Oxygen Demanding Substances (if landscape exists on-site) Oil & Grease Pesticides (if landscape exists on-site) Heavy Metals Organic Compounds Trash & Debris Oxygen Demanding Substances Oil & Grease Sediments Nutrients (if landscape exists on-site) Heavy Metals Organic Compounds (including petroleum hydrocarbons) Trash & Debris Oxygen Demanding Substances (includes solvents) Oil & Grease Bacteria & Viruses Pesticides (if landscape exists on-site) SB&O INC. 9.0 Identification of Pollutants of Concern Pollutants Associated Pollutants Causing Impairment to 303(d) with Priority Project Cateeorv Receiving Water(s) □ Chloride D Copper [8J Sediment [8J Nutrients D Phosphorus D Sediment □ Chloride [8J Nutrients D Eutrophic [8J Nutrients D Phosphorus D Copper [8J Heavy Metals D Manganese D Sediment Toxicity [8J Organic Compounds D Eutrophic D Sediment Toxicity D Eutrophic [8J Trash & Debris D Nutrients [8J Sediment Toxicity [8J Oxygen Demanding D Eutrophic [8J Nutrients Substances D Phosphorus [8J Oil & Grease D Eutrophic [8J Sediment Toxicity D Enterococcus [8J Bacteria & Viruses D Eutrophic D Fecal Coliform D Copper [8J Pesticides D Eutrophic D Phosphate D Total Nitrogen as N QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 12 [8J Sediment/Siltation [8J Sediment Toxicity [8J Selenium D Sulfates D Total Nitrogen as N D Sulfates D Total Dissolved Solids D Total Nitrogen as N D Toxicity D Sulfates D Total Dissolved Solids D Toxicity D Toxicity D Total Dissolved Solids D Toxicity D Sulfates D Total Dissolved Solids D Total Nitrogen as N D Toxicity [8J Indicator Bacteria D Total Coliform [8J Sediment Toxicity D Sulfates D Toxicity Pollutants of Concern [8J Sediment [8J Nutrients D Heavy Metals D Organic Compounds [8J Trash & Debris [8J Oxygen Demanding Substances [8J Oil & Grease [8J Bacteria & Viruses [8J Pesticides SB&O INC. 10.0 Hydromodification Management Plan (HMP) Applicability Determination NO YES YES HMP Exempt End of Decision Mabix Figure 6-1. HMP Applicability Determination QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 13 NO 11. Determine Domain of Analysis YES See HMP Section 52 l+.;.;;,;;<J NO Redesign Energy Dissipation Syslem 14. Hydromodification Controls Required Go to Figure 6-2 of Decision Malrix SB&O INC. 11.0 Summary of HMP Compliance Approach Summary of Project HMP Compliance Approach D Not Applicable -Project Exempt from HMP requirements D Determine/Identify Point(s) of Compliance D Utilize SCCWRP Screening Tools to determine Stream Susceptibility D Default to a High Susceptibility Stream (0.1 Q2) [8J Utilize an appropriate HMP Sizing Tool to demonstrate HMP compliance D Utilize HMP Sizing Tables to demonstrate HMP compliance [8J Utilize an approved Continuous Simulation Model and compare pre- project and mitigated post-project flows to demonstrate HMP compliance 0HEC-HMS 0HSPF [8J SOHM 0SWMM D Provide comprehensive, digital support data, calculation method and parameters, and calculation results on Compact Disk (CD) sufficient to duplicate study and support a RWQCB audit See "Storm Water Management Plan Quarry Creek" dated March 19, 2015, by Project Design Consultants, for HMP compliance documentation. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 14 SB&O INC. 12.0 Permanent Source Control Best Management Practices (BMPs) Source Control BMP ~ Storm Drain Inlet Labeling Comment: D Outdoor Material Storage Areas Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 15 Applicable Implementation Requirements ~ Provide prohibitive dumping placards and/or signage ~ Post signage at public access points to deter prohibitive dumping ~ Maintain legibility of placards and signage 0 Not Applicable D Materials placed in an enclosure ( e.g. cabinet, shed, or similar structure that prevents contact with rain, runoff or spillal?;e to the storm water conveyance system) D Protected by secondary containment structures ( e.g. berms, dikes, or curbs) and paved or sufficiently impervious to contain leaks and spills D The storage area is paved and sufficiently impervious to contain leaks and spills D Includes a roof or awning to minimize direct precipitation to the secondary containment area ~ Not Applicable SB&O INC. 12.0 Permanent Source Control BMPs (continued) Source Control BMP IZ! Common Trash Enclosure and Recyclable Material Storage Areas Comment: IZ! Employ Integrated Pest Management (1PM) Practices Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 16 Applicable Implementation Requirements IZ! Paved with an impervious surface IZ! Designed not to allow run-on from adjoining areas IZ! Screened or walled to prevent off-site transport of trash IZ! Use trash containers with attached lids to exclude rain and maintain lids in closed position while not in use and/or include a roof or awning to minimize direct precipitation. IZ! Acknowledgment that installation of storm drain inlets or area drains in designated trash storage areas is prohibited 0 Not Applicable IZ! Plant pest-resistant or well-adapted plant varieties such as drought tolerant and/or native plants IZ! Discourage pests by modifying the site and landscaping design IZ! Distribute 1PM educational materials to future occupants as part of the final engineering phase Operation and Maintenance Plan (O&M Plan) which addresses physical pest elimination techniques such as relying on natural enemies to consume pests, weeding, pruning, and etc. Emphasis placed on correct and limited use of pesticides as a last line of defense 0 Not Applicable SB&O INC. 12.0 Permanent Source Control BMPs ( continued) Source Control BMP ~ Use of Efficient Irrigation Systems & Drought Tolerant Landscape Design D Interior Floor Drains and Elevator Shaft Sump Pumps Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 17 Applicable Implementation Requirements ~ Employ rain shutoff devices to prevent irrigation during and after precipitation ~ Design irrigation systems for the specific water requirements of each landscape area ~ Use flow reducers or shutoff valves triggered by a pressure drop to control water loss in the event of broken sprinkler heads or lines ~ Provide water conservation educational materials to future occupants. 0 Not Applicable D Properly connected to a sanitary sewer QI., D An alternate method, as approved by the City Engineer D Acknowledgment that direct connection of interior floor drains and elevator shaft pumps to private or public storm drain or sanitary sewer is not permissible ~ Not Applicable SB&O INC. 12.0 Permanent Source Control BMPs ( continued) Source Control BMP Applicable Implementation Requirements D Prohibit vehicle washing D Prohibit pressuring washing of parking surface in the parking garage and D Provide adequate treatment control BMPs to treat runoff prior to discharge to an MS4 and D Provide prohibitive dumping signage and floor drain marking; prominently displayed inside the parking garage and at the floor drains, respectively and; D Interior Parking Garages D Implement dry clean-up methods for non-hazardous accidental spills Equipped with Floor Drains D Equipped with a clarifier or other pretreatment facility D Properly connected to a sanitary sewer or, D An alternate method, as approved by the City Engineer D Acknowledgment that direct connection of interior floor drains and elevator shaft pumps to the sanitary sewer or storm water conveyance is not permissible [2] Not Applicable Comment: [2] A pet waste station that includes eye level, post mounted signage which reads "pick-up after your pet" or similar [2] Pet Use Areas approved language and DA pet waste disposal receptacle equipped with a lid 0 Not Applicable Comment: Pet waste station(s) will be provided at the southerly trail adjacent to the basins. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 18 SB&O INC. 13.0 Identification of BMPs Applicable to Individual Priority Project Categories Individual Priority Project Catee:ory D Private Roads Comment: ~ Residential Driveways & Guest Parking Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 19 Applicable Best Management Practice D Rural Swale System D Urban Curb/Swale System D Dual Drainage System D An alternate method, as approved by the City Engineer ~ Not Applicable D Designed to drain into adjacent landscape prior to discharging to a storm water conveyance ~ Shared access D Flared or piano shaped entrance (single lane at street) D Wheelstrips (paving only under tires) D Porous paving/Permeable surface □ Not Applicable SB&O INC. 13.0 Identification of BMPs Applicable to Individual Priority Project Categories (continued) Individual Priority Project Cateeorv D Dock Areas (Truck Wells) Comment: D Maintenance and Repair Bays Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 20 Applicable Implementation Requirements D Covered loading dock areas or, D Designed to preclude urban run-on and runoff D Containment method to isolate dock and facilitate pollutant removal, such as a shut-off valve and containment area D Equipped with a clarifier or other pretreatment facility D An alternate method, as approved by the City Engineer D Acknowledgement that direct connections to storm drains from depressed loading docks are prohibited lZJ Not Applicable D Located indoors and, D Designed to preclude urban run-on and runoff from adjacent areas D Self-contained bay drainage system (i.e. dead-end sump, with no outlet to offsite facilities) designed to capture all wash water, leaks, and spills. The self-contained drainage system shall connect to a "dead end sump" for collection and proper disposal D Acknowledgement that connection of maintenance and repair bay drains to the sanitary sewer or storm water conveyance system is prohibited. lZJ Not Applicable SB&O INC. 13.0 Identification of BMPs Applicable to Individual Priority Project Categories (continued) Individual Priority Project Catee:ory D Vehicle and Equipment Wash Areas Comment: D Outdoor Processing Areas Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 21 Applicable Best Management Practice D Paved with an impervious surface D Self-contained to preclude urban run-on and runoff D Preferably located indoors or, D Covered with a roof or overhang D Equipped with a clarifier or other pretreatment facility D Properly connected to a sanitary sewer or, D An alternate method, as approved by the City Engineer D Acknowledgement that connection of vehicle and equipment wash areas to the storm water conveyance system is prohibited ~ Not Applicable D Cover or enclose areas of that are a source of pollutants, D Grade or berm the perimeter of the processing area to prevent run-on or runoff D Sloped to a self-contained drainage system (i.e. "dead-end sump", with no outlet to offsite facilities) designed to capture all wash water, leaks, and spills. The self-contained drainage system shall connect to a "dead end sump" for collection and proper disposal D Equipped with a clarifier or other pretreatment facility D Properly connected to a sanitary sewer or, D An alternate method, as approved by the City Engineer D Acknowledgement that installation of storm drain inlets in outdoor processing areas and connection to a storm water conveyance system is prohibited ~ Not Applicable SB&O INC. 13.0 Identification of BMPs Applicable to Individual Priority Project Categories (continued) Individual Priority Project Catesmrv D Fueling Areas Comment: D Retail and Surface Parking Areas Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 22 Applicable Best Management Practice D Paved with an impervious PCC surface D Graded at a minimum slope to prevent pond formation D Separated by grade break, curb, or berm to prevent run-on D Covered with a canopy that extends a minimum often feet in each horizontal direction, for each pump, or alternatively; D Covered the fuel area with minimum dimensions equal to or greater than the area within the grade break or fueling area ( defined as extending 6.5 feet from the corner of each fuel dispenser or the length at which each hose and nozzle assembly may be operated plus one foot, whichever is greater D The canopy shall not drain to the fueling area D Acknowledgement that connection of fueling areas to the sanitary sewer or storm water conveyance system is prohibited ~ Not Applicable D Where landscaping is proposed in surface parking areas (both covered and uncovered), incorporate landscape areas into the drainage design D Overflow parking (i.e. parking in excess of the minimum parking requirements for the project) may be constructed of permeable paving ~ Not Applicable SB&O INC. 13.0 Identification of BMPs Applicable to Individual Priority Project Categories ( continued) Individual Priority Project Cateeorv ~ Steep Hillside Landscaping Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 23 Applicable Best Management Practice ~ Steep hillside areas disturbed by project development shall be landscaped with deep rooted, drought-tolerant plant species selected for erosion control and stabilized with mulch, consistent with the statewide Water Conservation in Landscape Act □ Not Applicable SB&O INC. 14.0 Implementation of Site Design Low Impact Development (LID) Practices LID Practice Applicable Design Characteristics [8J Preserve natural drainage features [8J Preserve existing trees and vegetation D Minimize soil disturbance [8J Clustering or concentrating development on the least [8J Conserve Natural Areas environmentally sensitive areas; consistent with SUSMP §4.1 (e.g. developing on ... previously graded areas, areas containing of non-native vegetation and etc.) [8J Incorporation of open space Lot( s) D An alternate method, as approved by the City Engineer 0 Not Applicable Comment: Done as part of the Quarry Creek Master Plan. [8J Minimize Impervious Surfaces Comment: QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 24 [8J Minimize the impervious footprint by increasing building density and/or by incorporating multiple-storied architecture [8J Construct streets, sidewalks, and parking lot drive aisles to minimum widths, provided public safety is not compromised [8J Incorporate landscape buffers between sidewalks, streets, and other flatwork [8J Minimize impervious surfaces in landscape design; such as decorative or stamped concrete D Using permeable surfaces (porous concrete, pavers, asphalt) in overflow parking or low-traffic areas D An alternate method, as approved by the City Engineer 0 Not Applicable SB&O INC. 14.0 Implementation of Site Design Low Impact Development (LID) Practices (continued) LID Practice Applicable Design Characteristic C8] Minimize disturbance to natural drainages C8] Convey runoff safely from the tops of slopes D Vegetate slopes with native or drought tolerant landscape C8J Protect Slopes and Channels D Stabilize permanent channel crossings 0 Install Energy Dissipaters 0 An alternate method, as approved by the City Engineer 0 Not Applicable Comment: The downstream storm drain discharge locations include energy dissipaters, and combination (hydromodification & detention) basins. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 25 SB&O INC. 15.0 Relative Effectiveness of Project Treatment Facilities Relative Effectiveness of Project Treatment FacWties and IMPs Treatment Facility/IMP ~ Bioretention IMP □ Flow Through Planter IMP D Infiltration IMP D Conventional Vegetated Swale D Extended (Dry) Detention Basins D Media (Sand) Filter D Wet Pond D Constructed Wetland D Proprietary Vault/Tree Well D Proprietary Inlet Filter QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 26 Pollutants Grouped bv Method of Transport Coarse Pollutants Associated with Sediment Fine Particles During and Trash Transport High High High High High High High Medium High High High High High High High High High Medium High Low Pollutants that tend to be Dissolved Following Treatment Medium Medium High Low Low Low Medium Medium Low Low SB&O INC. - ---------------- ------ ----- - ---- 16.0 Comparison of Water Quality Areas Draina~e Basin SB&O PDC Basin 1 (Basin BB-1) Impervious Area 6.59 6.85 Future Cultural Center -- Total Basin 1 Area 13.73 13.72 Basin 3-2A Impervious Area 1.26 1.40 Total Basin Area 8.62 8.66 Basin 3-2B Impervious Area 3.43 3.50 Total Basin Area 4.69 5.20 Total Impervious Area 11.28 11.75 Total Drainage Area 27.04 27.58 The above comparison confirms that the proposed impervious areas and tributary areas to each basin are consistent with the original design assumptions in the Master SWMP (PDC). The grading for Basin BB-1 was subsequently revised, creating a larger water quality basin area than originally designed. The bottom basin area increased from 14,316 SF to 15,612 SF (approximately 9% increase) which will allow for treatment of a larger impervious area to drain into Basin BB-1. Please refer to Exhibit "A" in the Figures Section for a copy of the basin changes. Notes: The proposed tributary drainage areas and impervious areas are shown on SWMP Exhibit for Quarry Creek R-1/R-2 in the Map Pocket. A copy of the "Summary of Drainage & Impervious Areas" form the Master WOTR (PDC) 1s provided in the Attachments Sections. The offsite future cultural center development east of the R-1 site will be per a separate project; therefore an impervious area cannot be calculated at this time. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 27 SB&O INC. """ .. """ -17.0 Summary and Conclusion Narrative ---.... - .. ... ... - .. .. ---.. ---------... --... ---- This SWMP has identified the project as a Priority category that is required to implement Low Impact Development, Treatment Control, and hydromodification mitigation measures. The potential pollutants to be generated from this project have been identified and compared to the impairments of all downstream bodies of water leading to the Pacific Ocean . In order to mitigate for these potential pollutants, the combined R-1 and R-2 Planning Areas and existing offsite street improvements will discharge to bioretention basins BB 3-2A, BB 3-2B and BB-1 as defined and described in the Master SWMP (PDDC). These basins also mitigate for potential hydromodification impacts to the downstream receiving waters . As shown in the comparison table in Section 16.0, the proposed impervious and total basin tributary areas are consistent with PDC's original design assumptions. The R-1 and R-2 Planning Areas are consistent with the applicable Integrated Management Practices (IMPs) to be constructed in accordance with the Master SWMP and construction drawings. QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 28 SB&O INC. 1111' ... --... -... -... ------------------.. -- ----.. - 18.0 Figures Vicinity Map Basin BB-1 Exhibit Proposed DMA Exhibit R-1 & R-2 (Map Pocket) QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 29 SB&O INC. -... - -.... -.. -------... -... -.... -.. - -.. - --.. .. -.. ... -- EL CAMINO COUNTRY CLUB MIRA 'OSTA COLLEGE 8 . ~ HA>UAR DR. MARRON RD. WAY PAcKABP---- VICINITY MAP NOT TO SCALE THOMAS BROTHERS PG. 1107, GRID A-2 2006 EDITION ~ "?i SITE a I• i Ii I Iii I If I 11 11 11 11 11 11 11 11 11 11 f I 11 • .... L£GENO I WEST I £4ST I TOTAL 1-20-6' EXIST. POC BOTTOM BASIN AR£4 PROPOSED SB&O BOTTOM BASIN AR£4 BASIN DATA TABLE ORGINAL REVISE CHANGE ARD! (S.F.) ARD! {S.F.) (S.F.) 6,044 6,044 - 8,272 9,575 +f,303 14316 15. 619 +1,.]03 EXH/BIT':4• BASIN BB-1 AREAS 71920.60 -------------=c----'= / ,' ; I -- -----.::__ -=-~-- Ii : i ---~--------- '· ! I 1 '' I I Z:: RIGHT-OF-WAY UN£ CURB AND GUTTER £){fSTlNG CONTOUR PROPOSED DM4 UM/TS DIRECTlON OF DRAINAGE IMPERVIOUS AREA LANDSCAPE AREA STORM DRAIN PIPE SIZE D.M.A. TABLE D.M.A. NAME PROPOSED ONSITF PAD IMPERVIOUS AR£4 (AC) BASIN 1 6.59 BASIN 3-.24 1.26 BASIN 3-2B 3.43 SWMP EXHIBIT FOR: QUARRY CREEK PLANMNG AREA R·f AND R:2 ----.; ------ I =%= ' ' • I I, ' -~:il~--..:-::..-:~:-,C--',><::/ _, SOURCE CONTROL BMP's [ZI STORM DRAIN INLET STENCIUNG. [Ij COMMON AREA TRASH AND RECYCUNC AR£<!. II] INTEGRATED PEST M4NAGEMENT, EmCIENT IRRIGATION AND DROUGHT TOLERANT LANDSCAPE STEEP HILLSIDE LANDSCAPING. PET WASTE Sli4770N AT TRAIL (LOCATION TO BE DETERMINED}. GRAPHIC SCALE 60 0 60 120 1850-:? SWMP EXHIBIT FOR: 180 QUARRY CREEK PLANNING AREA R·f AND R-2 PLANNING ENGINEERING SURVEYING 3880 Ruffin Road, Suite 120 San Diego, Ca. 92123 858-560-11 41 858-560-8157 Fax ~~z/d(!p i ALLEN L. Bl/fffHER DATE ~ ~,;,_;;;;,skt~~~,;:-~2~1=-"'i166----------------------------------------------------------------~77'.1r'.;g~'2;:2.sx,sxiv1;1;:-'.'.ss~w;;.z~;.;;'P.~.D~w,vct;; ____________________________________________________________ ,,,.. _______ ;7~1~92,!ioo..2200 -------- - - - - - ... - ... .. .. - .. .. 19.0 Attachments City of Carlsbad Storm Water Standards Questionnaire Master Drainage Area Exhibit (PDC) Summary of Drainage & Impervious Areas (PDC) Geo technical Study reference Permanent BMP Certification Form (see Project Design Consultants [PDC] master report) QUARRY CREEK R-1 & R-2 Priority Development Project -SWMP Page 30 SB&O INC. ---- -- -.. --... -.. ... ... ... ... .. .. .. .. ( City of Carlsbad STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov To address post-development pollutants that may be generated from development projects, the City requires that new development and significant redevelopment priority projects Incorporate Permanent Storm Water Best Management Practices (BMP's) Into the project design per the City's Standard Urban Stormwater Management Plan (SUSMP). To view the SUSMP, refer to the Engineering Standards (Volume 4, Chapter 2) . Initially this questionnaire must be completed by the applicant In advance of submitting for a development application (subdivision, discretionary permits and/or construction permits). The results of the questionnaire determine the level of storm water standards that must be applied to a proposed development or redevelopment project. Depending on the outcome, your project will either be subject to 'Standard Stormwater Requirements' or be subject to additional criteria called 'Priority Development Project Requirements'. Many aspects of project site design are dependent upon the storm water standards applied to a project. Your responses to the questionnaire represent an initial assessment of the proposed project conditions and Impacts. City staff has responsibility for making the final assessment after submission of the development application. If staff determines that the questionnaire was incorrectly filled out and ls subject to more stringent storm water standards than Initially assessed by you, this will result in the return of the development application as incomplete. In this case, please make the changes to the questionnaire and resubmit to the City . ff you are unsure about the meaning of a question or need help In determining how to respond to one or more of the questions, please seek assistance from Land Development Engineering staff. A separate completed and signed questionnaire must be submitted for each new development application submission. Only one completed and signed questionnaire is required when multiple development applications for the same project are submitted concurrently. In addition to this questionnaire, you must also complete, sign and submit a Project Threat Assessment Form with construction permits for the project Please start by completing Step 1 and follow the instructions. W11en completed, sign the form at the end and submit this with your application to the city . . . . . .. . : $TEP 1 ·· . .· . ·. · .. · . .... . .. to BE ¢OMPLEtEbtFoR ALL,PROJECts: To determine If your project is a priority development project, please answer the following questions: 1. Is your project LIMITED TO constructing new or retrofitting paved sidewalks, bicycle lanes or trails that meet the following criteria: (1) Designed and constructed to direct storm water runoff to adjacent vegetated areas, or other non-erodible permeable areas; OR (2) designed and constructed to be hydraulically disconnected from paved streets or roads; OR (3) designed and constructed with permeable pavements or surfaces in accordance with USEPA Green Streets auidance? 2. Is your project LIMITED TO retrofitting or redeveloping existing paved alleys, streets, or roads that are designed and constructed in accordance with the USEPA Green Streets guidance? YES NO X X If you answered "yes• to one or more of the above questions, then your project is NOT a priority development project and therefore is NOT subject to the storm water criteria required for priority development projects. Go to step 4, mark the last box stating "my project does not meet PDP requirements" and complete applicant Information. If you answered •no• to both auestlons, then go to Ster:, 2 . E-34 Page 1 of 3 Effective 6/27/13 --.. .. .. --.. -----.. -- ------- - --- -- . ,. , .. ,. ____ ,_ ... ~---~--~----, STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www .carlsbadca.gov . .. . . STEP2 · .. . · . .. JO_ BE ,COMPLETED FOR ALL NE:W 0:R REOE\/ELOPM~NT PcROJECTS . .. .. , To determine If your project is a priority development project, please answer the following questions: YES 1. Is your project a new development that creates 10,000 square feet or more of impervious surfaces collectively over the entire project site? This Includes commercial, Industrial, residential, mixed-use, and public X development projects on public or private land. 2. Is your project creating or replacing 5,000 square feet or more of impervious surface collectively over the entire project site on an existing site of 10,000 square feet or more of impervfous surface? This Includes commercial, Industrial, residential mixed-use, and oubtlc development orotects on public or orivate land. 3. Is your project a new or redevelopment project that creates 5,000 square feet or more of impervious surface collectively over the entire project site and supports a restaurant? A restaurant Is a facility that sells prepared foods and dr/nl<s for consumption, including stationary lunch counters and refreshment stands sef/fng prepared foods and drinl<s for Immediate consumotlon . 4. Is your project a new or redevelopment project that creates 5,000 square feet or more of Impervious surface collectively over the entire project site and supports a hillside development project? A hillside development project Includes development on any natural slope that Is twenty.five percent or greater. 5. Is your project a new or redevelopment project that creates 5,000 square feet or more of Impervious surface collectively over the entire project site and supports a parking lot A parking lot is a land area or facI7ity for the temoorary parking or stQrage of motor vehicles used person~//y for business or for commerce. 6. Is your project a new or redevelopment project that creates 5,000 square feet or more of Impervious surface collectively over the entlre project site and supports a street, road, highway freeway or driveway? A street, road, highway, freeway or driveway Is any paved impervious surface used for the transportation of X automobiles trucks, motorcycles, and other vehicles. 7. Is your project a new or redevelopment project that creates or replaces 2,500 square feet or more of impervious surface collectively over the entire site, and discharges directly to an Environmentally Sensitive Area (ESA)? "Discharging Directly to" fnaludes flow that Is conveyed overland a distance of 200 feet or less from the project to the ESA, or conveyed In a pipe or open channel any distance as an isolated flow from the oro/ect to the ESA (i.e. not commingles with flows from adjacent lands).• 8. Is your project a new development that supports an automotive repair shop? An automotive repair shop Is a fact1ity that is categorized In any one of the following Standard Industrial Classification (SIC) codes: 5013, 5014, 5541, 7532~7534, or 7536-7539. 9. Is your project a new development that supports a retail gasoline outlet (RGO)? This category includes RGO's that meet the following criteria: (a) 5,000 square feet or more or (b) a project Average Daily Traffic (ADT) of 1 DO or more vehicles oer day. 10. ls your project a new or redevelopment project that results in the disturbance of one or more acres of land and are expected to generate pollutants post construction? X 11.ls your project located within 200 feet of the Pacific Ocean and (1) creates 2,500 square feet or more of impervious surface or (2) increases impervious surface on the property by more than 10%? NO X X X X X X X X If you answered "yes" to one or more of the above questions, you ARE a priority development project and are therefore subject to Implementing structural Best Management Practices (BMP's) In addition to implementing Standard Stonn Water Requirements such as source control and low Impact development BMP's. A Storm Water Management Plan (SWMP) must be submitted with your apptlcatlon(s) for development. Go to step 3 for redevelopment projects. For new projects, go to step 4 at the end of this questionnaire, check the "my project meets PDP requirements" box and complete applicant Information. If you answered "no" to all of the above questions, you ARE NOT a priority development project and are therefore subJect to implementing only Standard Storm Water Requirements such as source control and low Impact development BMP's required for all development projects. A Storm Water Management Plan (SWMP) Is not required with your application(s} for development Go to atep 4 at the end of this questionnaire, check the "my proJect does not meet PDP requirements" box and complete applicant Information. E-34 Page 2 of3 Effective 6127113 ---- .... -.. --.. .. "' • • .. ... .. .. { City of __ lsbad STORM WATER STANDARDS QUESTIONNAIRE E-34 Development Services Land Development Engineering 1635 Faraday Avenue 760-602-2750 www.carlsbadca.gov . · . · . . ·. STEP;3 · · · . . · __ . · .. ·. :c MP.1.ET:ED;FO , If ... ·. L P E PR . ·TS THAT ARE PRIORITY DEVELOP~MENT:PROJECTSONLY . Com lete the uestions below re ardln our redevelo ment ro ect: YES NO Does the redevelopment project result in the creation or replacement of impervious surface In an amount of less than 50% of the surface area of the revlousl existin develo ment? If you answered "yes,• the structural BM P's required for Priority Development Projects apply only to the creation or replacement of Impervious surface and not the entire development. Go to step 4, check the "my project meets PDP requirements" box and complete applicant Information. If you answered "no," the structural BM P's required for Priority Development Projects apply to the entire development. Go to step 4, check the "m ro ect meets PDP re ulrements" box and com lete a llcant information • ml My project meets PRIORITY DEVELOPMENT PROJECT (PDP) requirements and must comply with additional stonnwater criteria per the SUS MP and I understand I must prepare a Storm Water Management Plan for submittal at time of application. I understand flow control (hydromodification) requirements may apply to my project Refer to SUSMP for details . □ My project does not meet POP requirements and must only comply with STANDARD STORMWATER REQUIREMENTS per the SUSMP. As part of these requirements, I wllr incorporate low impact development strategies throughout my project. Applicant Information and Signature Box Address: 5993 Avenida Encinas Ste 101 Carlsbad. CA 92008 Applicant Name: Chelsea Investment Applicant Signature: Accessor's Parcel Number(s): -0 - Applicant Title: Date: 7, This Box for City Use Only City Concurrence: By: Date: Project ID: I YES I NO I I 11 Environmentally Sensitive Areas Include but are not limited to all Clean Water Act Section 303(d) impaired water bodies; areas designated as Areas of Special Biological Significance by the State Water Resources Control Board (Water Quality Control Plan for the San· Diego Basin (1994) and amendments); water bodies designated with the RARE beneficial use by the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments); areas designated as preserves or their qulvalent under the Multi Species Conservation Program within the Cities and County of San Diego; and any other equivalent environmentally sensitive areas which have been Identified by the Copermlttees . E-34 Page 3 of 3 Effective 6/27/13 ·•·· 3116/2015 r. 2468_02_DratnageBasil'\._ 11x17 P:\2468.20\GIS\M>d\2468_02_Draiiage8asin_ 11x 17 .mx.d · ib nay bt ~ fFtllff ,atfa,.s aoun::as with dilrelwnl .. ...,.. of ac:cuTEy.For d•talJ on •c::cv,.r:, d rtu uhtb'tpl_•.se-r'flM II &Li ta Oa.ia PIO'lliO:ed. L -__ JFeet 0 150 300 Biorentenlion/Hyd romocl Post Project Drainage Basins (ii}orainage Basin 1 -13.7 Ac. liiJ'Drainage Basin 3-2a -8.7 Ac. I Drainage Basin 3-2b -5.2 Ac. Drainage Basin 3-3 -7.5Ac. Drainage Basin 3-7 -3.7 Ac. (g] Drainage Basin 4 -24.6 Ac. ~ Drainage Basin 5 -7 .7 Ac. Drainage Basin! C PRG.IECT DESIGN CONSULTANTl ~ 1 11 11 11 It 11 11111111 I I 1111 II fl II fl fl fl WQ 85th Percentile depth= 0.65 in Basin Volume-based Sizing for Water Quality Treatment Requirements Provided Provided Basin WQ Basin Bottom Area with Current Computed% Bioretention/ Drainage Impervious Volume Volume Sandy Loam Basin Size Sizing Area Hydromod Basin Area (ac) Area (AC) C c1> WQ (AF)'2> (AF) (SF) Result factor 1 13.72 6.85 0.55 0.41 2.64 13138 OK 4 3-2-a 8.66 4.99 0.62 0.29 2.03 8705 OK 3.7 3-2-b 5.2 3.60 0.72 0.20 0.8 5708 OK 3.5 3-3 7.5 4.81 0.68 0.28 1.17 8896 OK 4 3-7 3.73 0.92 0.32 0.07 0.35 1725 0~ 3.3 4 24.59 15.09 0.65 0.87 6.54 27815 OK 4 5 7.72 5.47 0.74 0.31 1.63 10041 OK 4 Notes: 1) Cwa==Composite runoff factor per Section 4 of SUSMP=(impervious area*1 +0.1 *pervious area)/total area 2) WQ Vol=WQ 85th Percentile depth* Cw0* Area 3) Computed % sizing factor= Provided Basin Bottom Area with Sandy Loam (SF) / (Cwa * Area) * 100 ~ (f) 0 C 3 3 (1)3 CD Ol $1 '< -· 0 0 :::J ....... =O q ru 0 :::J ■--t■.O) s:: co Ol CD CJ) S<o ,-+ CD -., 3 ~"O 0~ -I <. JJ g CT en '< )> -a ., 0 CD ()~ .. ... -------... ------------------- - ,. I UPDATE GEOTECHNICAL INVESTIGATION QUARRY CREEK CARLS-BAD/OCEANSIDE, CALIFORNIA PREPARED FOR CORNERSTONE COMMUNITIES SAN DIEGO, CALIFORNIA FEBRUARY 24, 2015 PROJECT NO. 07135-42-05 -- -----.. -------------------- - ------... Gl?OTl!CH.NfCAL ■ ENViRONM~NTAl • MAT.ERIALS Project No. 0713-5-42-05 February 24, ~015 Cornerstone ~onnnunities 4365 Executive Drive, Suite 600 ~an Dieg<?, California 92i21 Attention: Mr. JackRobson Subject: · UPDATE GEOTECHNICAL INVESTIGATION QU-¥UlY CRE~K CARLSBAD/OCEANSIDE, CALIFORNIA Dear Mr. ~obson: . . . In accorda~ce .with your authorization, we are plyased to submit the resiµts of our update geotech,nlcal inyestigation for the proposed Quarry Creel_c proj ~ct. Conclusions and rec9mmyndations present~d hereln are based on review of available published geot~chnical reports and literature, observations during previous grading perfonned on the properly for reclamation, previous subsurface geotechnical exploration and site reconnaissance of existing conditions. Th~ eastern half of the property has been used for mining and crushing rock to produce commercial aggregates. As the result, the eastern half of the site is underlain by compacted fill, previously placed_ fill, undocumented fill, sedimentary, volcani<.;, and intrusive bedrock. Reclamation gr~ding has occurred on this portion of the site._ The western half of the site is in an ungraded natural condition. The ~ccompanying report presents fmdings from our studies relative to geotecbnical engineering aspects: of developing the prope~ty. -pie site is considered suitable for the proposed improvements provided the recommendations of this rep9rt are followed. Should you have questions regarding this report, or if we may be of further service, please contact the undersigned at your convenience. Very truly yours, GEOCONINCORPORATED IA /4A' /2 "----~ii <Sadr CEG 1778 AS:RCM:dmc (4/del) (2/del) Addressee The Corky McMillin ompames Attention: Mr. Don Mitchell .. -.. ... ... -- --... ... --------------------.. -- 7.1 7.1.1 7.1.2 7.1.3 7.1.4 7.1.5 7. CONCLUSIONS AND RECOMMENDATIONS General From a geotechnical engineering .standpoint, it is ow-opinion that the site is suitable for the proposed development, provided the recommendations presented herein are implemented in design and construction of the project. Soil conditions identified during this study that may impact development include compressible surficial soils (undocumented fill, alluvium, .. colluvium, surficial landslide debris and topsoil) that will require remedial grading. Undocumented fill may contain large rock fragments that require special placement procedures. The property is approximately 7 miles from the Newport Inglewooo/Rose Canyon Fault. It is our opinion active and potentially active faults do not extend across or trend toward the site. Risks associated with seismic activity consist of the potential for strong seismic shaking. Building setbacks will not be required for the planned development due to faulting. Several potential surficial landslides are mapped along the north"facing slope within the western portion of the site. Due to the limited access, these areas could not be reached for subsurface investigation. If encountered during the grading operations, total removal of the slide debris within the· grading area is recommended. Subsurface conditions observed may be extrapolated to reflect general soil/geologic conditions; however, some. variations in subsurface conditions between trench and boring locations should be anticipated. 7.2 Excavation and Soil Characteristics 7.2.1 7.2.2 Excavation ·of the Terrace Deposits, Santiago Formation and weathered portion of the Salto Intrusive is expected to require a heavy to very heavy effort to excavate. Less weathered and fresh Saito Intrusive bedrock may require blasting or specialized rock breaking techniques to efficiently excavate and handle. Very heavy effort with possible refusal is expected for ·excavations into the volcanic and intrusive rocks. Oversize material may be generated which would require special handling or exportation from the site. The soil encountered in the field investigation is considered to be "expansive" (expansion index greater than 20) as defined by 2013 California Building Code (CBC) Section 1803.5.3. Table 7.2 presents soil classifications based on the expansion index. Based on Project No. 07135-42-05 -11 -February 24, 2015