Murrieta City Council
May 20, 2025

County Project Specific Water Quality Management Plan
A Template for preparing Project Specific WQMPs for Priority Development Projects only for use in Riverside County located within the Santa Margarita Region.

Project Title: CarMax Murrieta #1824
Development No: TBD
Design Review/Case No: TBD
BMP1 (Latitude, Longitude): 33.551292, -117.192958, BMP2 (Latitude, Longitude): 33.54922, - 117.191325
s
Original Date Prepared: July 27, 2023
Revision Date(s): July 18, 2024, August 29, 2024
Based on 2018 WQMP, prepared for Compliance with
Regional Board Order No. R9-2013-0001 as amended by
Order No. R9-2015-0001 and Order No. R9-2015-0100
Contact Information
Prepared for:

Centrepoint Integrated Solutions, LLC
1240 Bergen Pkwy, Suite A 250
Evergreen, CO 80439
Prepared by: John Pollock, P.E.

Kimley-Horn and Associates, Inc.
3801 University Avenue, Suite 300
Riverside, CA 92501
Telephone: (951) 543-9868
Email: [email protected]
Preliminary
Final
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
2 A Brief Introduction
The Regional Municipal Separate Stormwater Sewer System (MS4) Permit1requires that a Project-Specific WQMP be prepared for all development projects within the Santa Margarita Region (SMR) that meet the ‘Priority Development Project’ categories and thresholds listed in the SMR Water Quality Management Plan (WQMP). This Project-Specific WQMP Template for Development Projects in the Santa Margarita Region has been prepared to help document compliance and prepare a WQMP submittal. Below is a flowchart for the layout of this Template that will provide the steps required to document compliance. 1 Order No. R9-2013-0001 as amended by Order Nos. R9-2015-0001 and R9-2015-0100, NPDES No. CAS0109266, National Pollutant Discharge Elimination System (NPDES) Permit and Waste Discharge Requirements for Discharges from the MS4s Draining the Watersheds within the San Diego Region, California Regional Water Quality Control Board, May 8, 2013.

Section A
• Project and Site Information
• Identification of LID and
Hydromodification
requirements, if any
Section B
• Optimize Site Utilization (LID
Principles)
Section C
• Delineate Drainage
Management Areas (DMAs)
Section D
• Technical Feasibility
• Implement LID BMPs
Section E
• Technical Feasibility
• Implement Hydromodification
BMPs
Section F
• Document Alternative
Compliance Measures
Section G
• Implement Trash Capture BMPs
Section H
• Specify Source Control BMPs
Section I
• Cordinate Submittal w/Other
Site Plans
Section J
• Operation, Maintenance, and
Funding
Section K
• Acronyms, Abbreviations, and
Definitions
Appendices
• Placeholders for supporting
material
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
3 OWNER’S CERTIFICATION
This Project-Specific WQMP has been prepared for CenterPoint Integrated Solutions, LLC by John Pollock for the Carmax Murrieta #1824 project.

This WQMP is intended to comply with the requirements of Riverside County for County Ordinance No. 754 which includes the requirement for the preparation and implementation of a Project-Specific WQMP.

The undersigned, while owning the property/project described in the preceding paragraph, shall be responsible for the implementation and funding of this WQMP and will ensure that this WQMP is amended as appropriate to reflect up-to-date conditions on the site. In addition, the property owner accepts responsibility for interim operation and maintenance of Stormwater Best Management Practices until such time as this responsibility is formally transferred to a subsequent owner. This WQMP will be reviewed with the facility operator, facility supervisors, employees, tenants, maintenance and service contractors, or any other party (or parties) having responsibility for implementing portions of this WQMP. At least one copy of this WQMP will be maintained at the project site or project office in perpetuity. The undersigned is authorized to certify and to approve implementation of this WQMP. The undersigned is aware that implementation of this WQMP is enforceable under Riverside County Water Quality Ordinance (No. 754).
"I, the undersigned, certify under penalty of law that the provisions of this WQMP have been reviewed and accepted and that the WQMP will be transferred to future successors in interest." Owner’s Signature Date
Owner’s Printed Name Owner’s Title/Position
PREPARER’S CERTIFICATION
“The selection, sizing and design of stormwater treatment and other stormwater quality and quantity control Best Management Practices in this plan meet the requirements of Regional Water Quality Control Board Order No. R9- 2013-0001 as amended by Order Nos. R9-2015-0001 and R9-2015-0100.” 8/29/2024
Preparer’s Signature Date
John Pollock P.E.

Preparer’s Printed Name Preparer’s Title/Position
Preparer’s Licensure:

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
4 Table of Contents
Section A: Project and Site Information ................................................................................................... 7 A.1 Maps and Site Plans.......................................................................................................................8 A.2 Identify Receiving Waters..............................................................................................................8 A.3 Drainage System Susceptibility to Hydromodification ....................................................................8 A.4 Additional Permits/Approvals required for the Project:..................................................................9 Section B: Optimize Site Utilization (LID Principles)................................................................................ 10 Section C: Delineate Drainage Management Areas (DMAs).................................................................... 15 Section D: Implement LID BMPs ............................................................................................................ 21 D.1 Full Infiltration Applicability......................................................................................................... 21 D.2 Biofiltration Applicability ............................................................................................................. 23 D.3 Feasibility Assessment Summaries............................................................................................... 25 D.4 LID BMP Sizing............................................................................................................................. 26 Section E: Implement Hydrologic Control BMPs and Sediment Supply BMPs.......................................... 29 E.1 Hydrologic Control BMP Selection................................................................................................ 29 E.2 Hydrologic Control BMP Sizing ..................................................................................................... 30 E.3 Implement Sediment Supply BMPs............................................................................................... 31 Section F: Alternative Compliance ......................................................................................................... 32 F.1 Identify Pollutants of Concern ...................................................................................................... 32 F.2 Treatment Control BMP Selection ................................................................................................ 35 F.3 Sizing Criteria ............................................................................................................................... 35 F.4 Hydrologic Performance Standard – Alternative Compliance Approach........................................ 36 Section G: Implement Trash Capture BMPs............................................................................................ 37 Section H: Source Control BMPs............................................................................................................ 39 Section I: Coordinate Submittal with Other Site Plans............................................................................ 40 Section J: Operation, Maintenance and Funding .................................................................................... 41 Section K: Acronyms, Abbreviations and Definitions.............................................................................. 42 Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
5 List of Tables
Table A-1 Identification of Receiving Waters............................................................................................8 Table A-2 Identification of Susceptibility to Hydromodification................................................................9 Table A-3 Other Applicable Permits.........................................................................................................9 Table C-1 DMA Identification................................................................................................................. 15 Table C-2 Type ‘A’, Self-Treating Areas................................................................................................... 17 Table C-3 Type ‘B’, Self-Retaining Areas................................................................................................. 18 Table C-4 Type ‘C’, Areas that Drain to Self-Retaining Areas................................................................... 18 Table C-5 Type ‘D’, Areas Draining to BMPs........................................................................................... 20 Table D-1 Infiltration Feasibility ............................................................................................................. 22 Table D-2 Geotechnical Concerns for Onsite Infiltration........................................................................ 23 Table D-3 Evaluation of Biofiltration BMP Feasibility............................................................................. 24 Table D-4 Proprietary BMP Approval Requirement Summary ................................................................ 24 Table D-5 LID Prioritization Summary Matrix ......................................................................................... 25 Table D-6 Summary of Infeasibility Documentation ............................................................................... 25 Table D-7 DCV Calculations for LID BMPs............................................................................................... 27 Table D-8 LID BMP Sizing ....................................................................................................................... 27 Table E-1 Hydrologic Control BMP Sizing ............................................................................................... 30 Table F-1 Summary of Approved 2010 303(d) listed waterbodies and associated pollutants of concern for the Riverside County SMR Region and downstream waterbodies........................................................... 33 Table F-2 Potential Pollutants by Land Use Type .................................................................................... 34 Table F-3 Treatment Control BMP Selection .......................................................................................... 35 Table F-4 Treatment Control BMP Sizing................................................................................................ 35 Table G-1 Sizing Trash Capture BMPs..................................................................................................... 38 Table G-2 Approximate precipitation depth/intensity values for calculation of the Trash Capture Design Storm.................................................................................................................................................... 38 Table G-3 Trash Capture BMPs .............................................................................................................. 38 Table I-1 Construction Plan Cross-reference .......................................................................................... 40 Table I-2 Other Applicable Permits........................................................................................................ 40 List of Appendices
Appendix 1: Maps and Site Plans........................................................................................................... 49 Appendix 2: Construction Plans............................................................................................................. 50 Appendix 3: Soils Information................................................................................................................ 51 Appendix 4: Historical Site Conditions ................................................................................................... 52 Appendix 5: LID Feasibility Supplemental Information ........................................................................... 53 Appendix 6: LID BMP Design Details ...................................................................................................... 60 Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
6 Appendix 7: Hydromodification ............................................................................................................. 61 Appendix 8: Source Control ................................................................................................................... 63 Appendix 9: O&M.................................................................................................................................. 74 Appendix 10: Educational Materials....................................................................................................... 80 Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
7 Section A: Project and Site Information
Use the table below to compile and summarize basic site information that will be important for completing subsequent steps. Subsections A.1 through A.4 provide additional detail on documentation of additional project and site information. The Regional MS4 Permit has effectively removed the ability for a project to be grandfathered from WQMP requirements. Even if a project were able to meet all the requirements stated in Section 1.2 of the WQMP, the 2014 WQMP requirements would apply.

PROJECT INFORMATION
Type of PDP: Redevelopment/Expansion
Type of Project: Commercial
Planning Case Number: N/A
Rough Grade Permit No.: N/A
Development Name: CarMax Murrieta #1824

PROJECT LOCATION
Latitude & Longitude (DMS): 33° 33' 0.23'' N, 117° 11' 30.60'' W Project Watershed and Sub-Watershed: San Deigo Region - Santa Margarita River, Murrieta Creek 24-Hour 85th Percentile Storm Depth (inches): 0.80
Is project subject to Hydromodification requirements? Y N (Select based on Section A.3) APN(s): 910-490-001, 910-490-002, 910-490-013
Map Book and Page No.: 910-140

PROJECT CHARACTERISTICS
Proposed or Potential Land Use(s) Commercial
Proposed or Potential SIC Code(s) 5012
Existing Impervious Area of Project Footprint (SF) 22,218 Total area of proposed Impervious Surfaces within the Project Limits (SF)/or Replacement 171,752 Total Project Area (ac) 4.82
Does the project consist of offsite road improvements? Y N Does the project propose to construct unpaved roads? Y N Is the project part of a larger common plan of development (phased project)? Y N Has preparation of Project-Specific WQMP included coordination with other site plans? Y N

EXISTING SITE CHARACTERISTICS
Is the project located within any Multi-Species Habitat Conservation Plan area (MSHCP Criteria Cell?)
Y N
Is a Geotechnical Report attached? Y N
If no Geotech. Report, list the Natural Resources Conservation Service (NRCS) soils type(s) present on the site (A, B, C and/or D)
Provide a brief description of the project: Three vacant lots with APNs of 910-490-001, 910-490-002, and 910-490-013 will be developed as part of expansion of the existing CarMax located on the southeast corner of Murrieta Hot Springs and Madison Avenue. The project will not be phased and will include 2 staging areas with a combined impervious area of 171,752 sf. No buildings are being proposed but onsite CMU wall screening and screening along Madison Avenue will be developed.

Paver and dirt roads are considered pervious for determining WQMP applicability.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
8 A.1 Maps and Site Plans
When completing your Project-Specific WQMP, include a map of the Project vicinity and existing site. In addition, include all grading, drainage, landscape/plant palette and other pertinent construction plans in Appendix 2. At a minimum, your WQMP Site Plan should include the following:
• Vicinity and location maps
• Parcel Boundary and Project Footprint
• Existing and Proposed Topography
• Drainage Management Areas (DMAs)
• Proposed Structural Best Management
Practices (BMPs)
• Drainage Paths
• Drainage infrastructure, inlets, overflows
• Source Control BMPs
• Site Design BMPs
• Buildings, Roof Lines, Downspouts
• Impervious Surfaces
• Pervious Surfaces (i.e. Landscaping)
• Standard Labeling
• Cross Section and Outlet details
Use your discretion on whether or not you may need to create multiple sheets or can appropriately accommodate these features on one or two sheets. Keep in mind that the Copermittee plan reviewer must be able to easily analyze your Project utilizing this template and its associated site plans and maps.

Complete the checklists in Appendix 1 to verify that all exhibits and components are included.

A.2 Identify Receiving Waters
Using Table A-1 below, list in order of upstream to downstream, the Receiving Waters that the Project site is tributary to. Continue to fill each row with the Receiving Water’s 303(d) listed impairments (if any), designated Beneficial Uses, and proximity, if any, to a RARE Beneficial Use. Include a map of the Receiving Waters in Appendix 1. This map should identify the path of the stormwater discharged from the site all the way to the outlet of the Santa Margarita River to the Pacific Ocean. Use the most recent 303(d) list available from the State Water Resources Control Board Website. (http://www.waterboards.ca.gov/sandiego/water_issues/programs/basin_plan/) Table A-1 Identification of Receiving Waters
Receiving
Waters
USEPA Approved 303(d) List
Impairments
Designated
Beneficial Uses
Proximity to RARE
Beneficial Use
Murrieta Creek
Chlorpyrifos, Copper, Iron, Magnesium
Nitrogen, Phosphorus, Toxicity
MUN; AGR; IND; PROC; GWR;
REC1 (potential); REC2; WARM; WILD N/A
Santa Margarita
River (Upper)
Indicator Bacteria; Iron; Manganese;
Nitrogen; Phosphorous; Toxicity
MUN; AGR; IND; REC1; REC2;
WARM; COLD; WILD; RARE 6 miles
Santa Margarita
River (Lower)
Benthic Community Effects;
Chlorpyrifos; Indicator Bacteria;
Nitrogen; Phosphorous; Toxicity.

MUN; AGR; IND; REC1; REC2; WARM;
COLD; WILD; RARE 24.25 miles
A.3 Drainage System Susceptibility to Hydromodification Using Table A-2 below, list in order of the point of discharge at the project site down to the Santa Margarita River2, each drainage system or receiving water that the project site is tributary to. Continue to fill each row with the material of the drainage system, and any exemption (if applicable). Based on the results, summarize the applicable 2 Refer to Exhibit G of the WQMP for a map of exempt and potentially exempt areas. These maps are from the Draft SMR WMAA as of January 5, 2018 and will be replaced upon acceptance of the SMR WMAA.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
9 hydromodification performance standards that will be documented in Section E. Exempted categories of receiving waters include:
• Existing storm drains that discharge directly to water storage reservoirs, lakes, or enclosed embayments, or
• Conveyance channels whose bed and bank are concrete lined all the way from the point of discharge to water storage reservoirs, lakes, enclosed embayments, or the Pacific Ocean. • Other water bodies identified in an approved WMAA (See Exhibit G to the WQMP) Include a map exhibiting each drainage system and the associated susceptibility in Appendix 1.

Table A-2 Identification of Susceptibility to Hydromodification Drainage System Drainage System Material Hydromodification Exemption Hydromodification Exempt
Underground Storm
Drain Pipe Network Cast in place concrete pipe Potentially Not Exempt Y N
Above ground
discharge
Compacted soils with check dams and
natural cover Potentially Not Exempt
Y N
Murrieta Creek Earthen Potentially Not Exempt
Y N
Summary of Performance Standards
Hydromodification Exempt – Select if “Y” is selected in the Hydromodification Exempt column above, project is exempt from hydromodification requirements.

Not Exempt-Select if “N” is selected in any row of the Hydromodification Exempt column above. Project is subject to hydrologic control requirements and may be subject to sediment supply requirements.

A.4 Additional Permits/Approvals required for the Project:

Table A-3 Other Applicable Permits
Agency Permit Required
State Department of Fish and Game, 1602 Streambed Alteration Agreement Y N State Water Resources Control Board, Clean Water Act Section 401 Water Quality Certification Y N US Army Corps of Engineers, Clean Water Act Section 404 Permit Y N US Fish and Wildlife, Endangered Species Act Section 7 Biological Opinion Y N Statewide Construction General Permit Coverage Y N
Statewide Industrial General Permit Coverage Y N
Western Riverside MSHCP Consistency Approval (e.g., JPR, DBESP) Y N Other (please list in the space below as required)
Y N
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
10 If yes is answered to any of the questions above, the Copermittee may require proof of approval/coverage from those agencies as applicable including documentation of any associated requirements that may affect this Project-Specific WQMP.

Section B: Optimize Site Utilization (LID Principles)
Review of the information collected in Section ‘A’ will aid in identifying the principal constraints on site design and selection of LID BMPs as well as opportunities to reduce imperviousness and incorporate LID Principles into the site and landscape design. For example, constraints might include impermeable soils, high groundwater, groundwater pollution or contaminated soils, steep slopes, geotechnical instability, high-intensity land use, heavy pedestrian or vehicular traffic, utility locations or safety concerns.

Opportunities might include existing natural areas, low areas, oddly configured or otherwise unbuildable parcels, easements and landscape amenities including open space and buffers (which can double as locations for LID Bioretention BMPs), and differences in elevation (which can provide hydraulic head).

Prepare a brief narrative for each of the site optimization strategies described below. This narrative will help you as you proceed with your Low Impact Development (LID) design and explain your design decisions to others.

Apply the following LID Principles to the layout of the PDP to the extent they are applicable and feasible.

Putting thought upfront about how best to organize the various elements of a site can help to significantly reduce the PDP's potential impact on the environment and reduce the number and size of Structural LID BMPs that must be implemented. Integrate opportunities to accommodate the following LID Principles within the preliminary PDP site layout to maximize implementation of LID Principles.

Site Optimization
Complete checklist below to determine applicable Site Design BMPs for your site.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
11 Project- Specific WQMP Site Design BMP Checklist
The following questions below are based upon Section 3.2 of the SMR WQMP will help you determine how to best optimize your site and subsequently identify opportunities and/or constraints, and document compliance.

SITE DESIGN REQUIREMENTS
Answer the following questions below by indicating “Yes,” “No,” or “N/A” (Not Applicable). Justify all “No” and “N/A” answers by inserting a narrative at the end of the section. The narrative should include identification and justification of any constraints that would prevent the use of those categories of LID BMPs. Upon identifying Site Design BMP opportunities, include these on your WQMP Site plan in Appendix 1.

Yes No N/A
Did you identify and preserve existing drainage patterns? Integrating existing drainage patterns into the site plan helps to maintain the time of concentration and infiltration rates of runoff, decreasing peak flows, and may also help preserve the contribution of Critical Coarse Sediment (i.e., Bed Sediment Supply) from the PDP to the Receiving Water. Preserve existing drainage patterns by:
• Minimizing unnecessary site grading that would eliminate small depressions, where appropriate add additional “micro” storage throughout the site landscaping. • Where possible conform the PDP site layout along natural landforms, avoid excessive grading and disturbance of vegetation and soils, preserve or replicate the sites natural drainage features and patterns.
• Set back PDP improvements from creeks, wetlands, riparian habitats and any other natural water bodies.
• Use existing and proposed site drainage patterns as a natural design element, rather than using expensive impervious conveyance systems. Use depressed landscaped areas, vegetated buffers, and bioretention areas as amenities and focal points within the site and landscape design.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer.

Existing drainage pattern will remain similar, stormwater runoff sheet flows to existing storm drains.

Yes No N/A
Did you identify and protect existing vegetation?
Identify any areas containing dense native vegetation or well-established trees and try to avoid disturbing these areas. Soils with thick, undisturbed vegetation have a much higher capacity to store and infiltrate runoff than do disturbed soils. Reestablishment of a mature vegetative community may take decades. Sensitive areas, such as streams and floodplains should also be avoided.
• Define the development envelope and protected areas, identifying areas that are most suitable for development and areas that should be left undisturbed. • Establish setbacks and buffer zones surrounding sensitive areas. • Preserve significant trees and other natural vegetation where possible.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. No mature trees are found on site. Existing vegetation will be removed, and additional landscaped areas will be added. No mature trees or vegetation are found onsite.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
12 Project- Specific WQMP Site Design BMP Checklist
Yes No N/A
Did you identify and preserve natural infiltration capacity? A key component of LID is taking advantage of a site's natural infiltration and storage capacity.

A site survey and geotechnical investigation can help define areas with high potential for infiltration and surface storage.
• Identify opportunities to locate LID Principles and Structural BMPs in highly pervious areas. Doing so will maximize infiltration and limit the amount of runoff generated. • Concentrate development on portions of the site with less permeable soils, and preserve areas that can promote infiltration.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. Soil types A and C were determined for the site. Based on the Geotechnical report, Infiltration rates were low and infiltrating is not feasible. A subsurface biofiltration with above ground MWS will be utilized. Limited landscape area provided due to maximization of staging area requires detention to be underground while keeping available landscape available for the MWS.

Yes No N/A
Did you minimize impervious area?
Look for opportunities to limit impervious cover through identification of the smallest possible land area that can be practically impacted or disturbed during site development. • Limit overall coverage of paving and roofs. This can be accomplished by designing compact, taller structures, narrower and shorter streets and sidewalks, clustering buildings and sharing driveways, smaller parking lots (fewer stalls, smaller stalls, and more efficient lanes), and indoor or underground parking. • Inventory planned impervious areas on your preliminary site plan. Identify where permeable pavements, or other permeable materials, such as crushed aggregate, turf block, permeable modular blocks, pervious concrete or pervious asphalt could be substituted for impervious concrete or asphalt paving. This will help reduce the amount of Runoff that may need to be addressed through Structural BMPs. • Examine site layout and circulation patterns and identify areas where landscaping can be substituted for pavement, such as for overflow parking. • Consider green roofs. Green roofs are roofing systems that provide a layer of soil/vegetative cover over a waterproofing membrane. A green roof mimics predevelopment conditions by filtering, absorbing, and evapotranspiring precipitation to help manage the effects of an otherwise impervious rooftop.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. Impervious areas were maximized to provide enough space for the staging areas and pervious areas were reduced.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
13 Project- Specific WQMP Site Design BMP Checklist
Yes No N/A
Did you identify and disperse runoff to adjacent pervious areas or small collection areas? Look for opportunities to direct runoff from impervious areas to adjacent landscaping, other pervious areas, or small collection areas where such runoff may be retained. This is sometimes referred to as reducing Directly Connected Impervious Areas. • Direct roof runoff into landscaped areas such as medians, parking islands, planter boxes, etc., and/or areas of pervious paving. Instead of having landscaped areas raised above the surrounding impervious areas, design them as depressed areas that can receive Runoff from adjacent impervious pavement. For example, a lawn or garden depressed 3"-4" below surrounding walkways or driveways provides a simple but quite functional landscape design element.
• Detain and retain runoff throughout the site. On flatter sites, smaller Structural BMPs may be interspersed in landscaped areas among the buildings and paving. • On hillside sites, drainage from upper areas may be collected in conventional catch basins and piped to landscaped areas and LID BMPs and/or Hydrologic Control BMPs in lower areas. Low retaining walls may also be used to create terraces that can accommodate LID BMPs. Wherever possible, direct drainage from landscaped slopes offsite and not to impervious surfaces like parking lots. • Reduce curb maintenance and provide for allowances for curb cuts. • Design landscaped areas or other pervious areas to receive and infiltrate runoff from nearby impervious areas.
• Use Tree Wells to intercept, infiltrate, and evapotranspire precipitation and runoff before it reaches structural BMPs. Tree wells can be used to limit the size of Drainage Management Areas that must be treated by structural BMPs. Guidelines for Tree Wells are included in the Tree Well Fact Sheet in the LID BMP Design Handbook.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. Runoff will not be directed to landscape areas. Stormwater will be collected and conveyed into the subsurface biofiltration units.

Yes No N/A
Did you utilize native or drought tolerant species in site landscaping? Wherever possible, use native or drought tolerant species within site landscaping instead of alternatives. These plants are uniquely suited to local soils and climate and can reduce the overall demands for potable water use associated with irrigation.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. Site landscaping will include native plant species.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
14 Project- Specific WQMP Site Design BMP Checklist
Yes No N/A
Did implement harvest and use of runoff?
Under the Regional MS4 Permit, Harvest and Use BMPs must be employed to reduce runoff on any site where they are applicable and feasible. However, Harvest and Use BMPs are effective for retention of stormwater runoff only when there is adequate demand for non-potable water during the wet season. If demand for non-potable water is not sufficiently large, the actual retention of stormwater runoff will be diminished during larger storms or during back-to-back storms.

For the purposes of planning level Harvest and Use BMP feasibility screening, Harvest and Use is only considered to be a feasible if the total average wet season demand for non-potable water is sufficiently large to use the entire DCV within 72 hours. If the average wet season demand for non-potable water is not sufficiently large to use the entire DCV within 72 hours, then Harvest and Use is not considered to be feasible and need not be considered further.

The general feasibility and applicability of Harvest and Use BMPs should consider:
• Any downstream impacts related to water rights that could arise from capturing stormwater (not common).
• Conflicts with recycled water used – where the project is conditioned to use recycled water for irrigation, this should be given priority over stormwater capture as it is a year-round supply of water.
• Code Compliance - If a particular use of captured stormwater, and/or available methods for storage of captured stormwater would be contrary to building codes in effect at the time of approval of the preliminary Project-Specific WQMP, then an evaluation of harvesting and use for that use would not be required. • Wet season demand – the applicant shall demonstrate, to the acceptance of the County of Riverside, that there is adequate demand for harvested water during the wet season to drain the system in a reasonable amount of time.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. There is no adequate demand for non-potable water during the wet season.

Yes No N/A
Did you keep the runoff from sediment producing pervious area hydrologically separate from developed areas that require treatment?
Pervious area that qualify as self-treating areas or off-site open space should be kept separate from drainage to structural BMPs whenever possible. This helps limit the required size of structural BMPs, helps avoid impacts to sediment supply, and helps reduce clogging risk to BMPs.

Discuss how this was included or provide a discussion/justification for “No” or “N/A” answer. Grading keeps landscape areas separate from impervious areas where necessary.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
15 Section C: Delineate Drainage Management Areas (DMAs) & Green Streets
This section provides streamlined guidance and documentation of the DMA delineation and categorization process, for additional information refer to the procedure in Section 3.3 of the SMR WQMP which discusses the methods of delineating and mapping your project site into individual DMAs. Complete Steps 1 to 4 to successfully delineate and categorize DMAs.

Step 1: Identify Surface Types and Drainage Pathways
Carefully delineate pervious areas and impervious areas (including roofs) throughout site and identify overland flow paths and above ground and below ground conveyances. Also identify common points (such as BMPs) that these areas drain to.

Step 2: DMA Delineation
Use the information in Step 1 to divide the entire PDP site into individual, discrete DMAs. Typically, lines delineating DMAs follow grade breaks and roof ridge lines. Where possible, establish separate DMAs for each surface type (e.g., landscaping, pervious paving, or roofs). Assign each DMA a unique code and determine its size in square feet. The total area of your site should total the sum of all of your DMAs (unless water from outside the project limits comingles with water from inside the project limits, i.e. runon). Complete Table C-1 Table C-1 DMA Identification
DMA Name or Identification Surface Type(s)1 Area (Sq. Ft.) DMA Type DMA 1 Impervious 37,668 Type D
DMA 2 Mixed 142,642 Type D
DMA 3 Impervious 5,200 Type D
DMA 4 Mixed 11,362 Type A
DMA 5 Mixed 13,237 Type A
Add Columns as Needed. Consider a separate DMA for Tree Wells or other LID principals like Self-Retaining areas are used for mitigation.

Step 3: DMA Classification
Determine how drainage from each DMA will be handled by using information from Steps 1 and 2 and by completing Steps 3.A to 3.C. Each DMA will be classified as one of the following four types:
• Type ‘A’: Self-Treating Areas:
• Type ‘B’: Self-Retaining Areas
• Type ‘C’: Areas Draining to Self-Retaining Areas
• Type ‘D’: Areas Draining to BMPs
Tree wells are considered Type ‘B’ areas, and their tributary areas limited to a 10:1 ratio are considered Type ‘C’ areas. If Tree wells are proposed, consider grading or other features to minimize the pervious runoff to the tree wells, to avoid overwhelming the trees. Type ‘A’, ‘B’, and ‘C’ are considered LID Principals that can be used to minimize or potentially eliminate structural LID BMPs.

If Tree wells are proposed, a landscape architect shall be consulted on the tree selection, since compliance will be determined based on the survival of the tree. The tree type should be noted on the WQMP site map.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
17 Step 3.A – Identify Type ‘A’ Self-Treating Area
Indicate if the DMAs meet the following criteria by answering “Yes” or “No”.

Yes No
Area is undisturbed from their natural condition OR restored with Native and/or California Friendly vegetative covers.

Yes No
Area is irrigated, if at all, with appropriate low water use irrigation systems to prevent irrigation runoff.

Yes No
Runoff from the area will not comingle with runoff from the developed portion of the site, or across other landscaped areas that do not meet the above criteria.

If all answers indicate “Yes,” complete Table C-2 to document the DMAs that are classified as Self-Treating Areas.

Table C-2 Type ‘A’, Self-Treating Areas
DMA Name or Identification Area (Sq. Ft.) Stabilization Type Irrigation Type (if any) DMA 4 11,362 De-minimis area N/A
DMA 5 13,237 De-minimis area N/A
Step 3.B – Identify Type ‘B’ Self-Retaining Area and Type ‘C’ Areas Draining to Self-Retaining Areas Type ‘B’ Self-Retaining Area: A Self-Retaining Area is shallowly depressed 'micro infiltration' areas designed to retain the Design Storm rainfall that reaches the area, without producing any Runoff.

Indicate if the DMAs meet the following criteria by answering “Yes,” “No,” or “N/A”.

Yes No N/A Inlet elevations of area/overflow drains, if any, should be clearly specified to be three inches or more above the low point to promote ponding.

Yes No N/A Soils will be freely draining to not create vector or nuisance conditions.

Yes No N/A
Pervious pavements (e.g., crushed stone, porous asphalt, pervious concrete, or permeable pavers) can be self-retaining when constructed with a gravel base course four or more inches deep below any underdrain discharge elevation.

If all answers indicate “Yes,” DMAs may be categorized as Type ‘B’, proceed to identify Type ‘C’ Areas Draining to Self-Retaining Areas.

Type ‘C’ Areas Draining to Self-Retaining Areas: Runoff from impervious or partially pervious areas can be managed by routing it to Self-Retaining Areas consistent with the LID Principle discussed in SMR WQMP Section 3.2.5 for 'Dispersing Runoff to Adjacent Pervious Areas'.

Indicate if the DMAs meet the following criteria by answering “Yes” or “No”.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
18 Yes No
The drainage from the tributary area must be directed to and dispersed within the Self-Retaining Area.

Yes No
The maximum ratio of Tributary Area to Self-Retaining area is (2 ÷ Impervious Fraction): 1
If all answers indicate “Yes,” DMAs may be categorized as Type ‘C’.

Complete Table C-3 and Table C-4 to identify Type ‘B’ Self-Retaining Areas and Type ‘C’ Areas Draining to Self-Retaining Areas.

Table C-3 Type ‘B’, Self-Retaining Areas
Self-Retaining Area Type ‘C’ DMAs that are draining to the Self-Retaining Area
DMA
Name/ ID
Post-project
surface type
Area
(square
feet)
Storm
Depth
(inches)
DMA Name / ID
[C] from Table
C-4=
Required Retention Depth
(inches)
[A] [B] [C] [D] = [𝐵] +
[𝐵]∙[𝐶]
[𝐴]
- - -
- - -
- - -
Note: Tree well areas can extend well beyond the drip line. The Tree Well area for open top types would include the shallow depressed area at the soil surface. The Tree Well area for Structural Soil Tree Wells or Suspended Pavement Tree Wells includes the area with open-graded gravel or void space over the structural soil or structural cells. Please specify type in this table and WQMP site map. See LID handbook Tree Well factsheet for additional details. (
𝟐 𝑰𝒎𝒑𝒆𝒓𝒗𝒊𝒐𝒖𝒔 𝑭𝒓𝒂𝒄𝒕𝒊𝒐𝒏) ∶ 𝟏
(Tributary Area: Self-Retaining Area)
Table C-4 Type ‘C’, Areas that Drain to Self-Retaining Areas DMA Receiving Self-Retaining DMA
DMA Name/ ID
Area
(square feet)
Post-project surface type
Runoff
factor
Product
DMA name /ID
Area (square
feet) Ratio
[A] [B] [C] = [A] x [B] [D] [C]/[D]
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
19 Note: (See Section 3.3 of SMR WQMP) Ensure that partially pervious areas draining to a Self-Retaining area do not exceed the following ratio:

Step 3.B.1 – Document the use of Green Street Exemption (see Section 3.11 of the WQMP Guidance) The Regional MS4 Permit specifies that projects that consist of retrofitting or redevelopment of existing paved alleys, streets, or roads may be exempted from classification as PDPs if they are designed and constructed in accordance with USEPA Green Streets Guidance. This does not apply for interior roads for PDP projects. For projects with road frontage improvements, Green Street standards can be used in the frontage road right-of-way. The remainder of the project is subject to full WQMP and Hydromodification requirements. See excerpt from Section 3.11 of the WQMP Guidance below:

3.11.4 BMP Sizing Targets for Applicable Green Streets Projects Applicable green street projects are not required to meet the same sizing requirements for BMPs as other projects, but should attempt to meet a sizing target to the MEP. The following steps are used to size BMPs for applicable Green Streets projects:

1. Delineate drainage areas tributary to BMP locations and compute imperviousness.

2. Determine sizing goal by referring to sizing criteria presented in Section 2.3.2 (VBMP).

3. Attempt to provide the target BMP sizing according to Step 2.

4. If the target criteria cannot be achieved, document the constraints that override the application of BMPs, and provide the largest portion of the sizing criteria that can be reasonably provided given constraints.

Even if BMPs cannot be sized to meet the target sizing criteria, it is still important to design the BMP inlet, energy dissipation, and overflow capacity for the full tributary area to ensure that flooding and scour is avoided. It is strongly recommended that BMPs which are designed to less than their target design volume be designed to bypass peak flows.

Table C-4.1 – Green Streets
DMA Name or ID Street Name BMP Sizing Targets Calculations and documenting constraints
included in Appendix 6*
N/A N/A Yes No
Yes No
Yes No
Yes No
Yes No
*WQMP shall not be approved without calculations or documenting constraints for Green Street Exemption.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
20 Step 3.C – Identify Type ‘D’ Areas Draining to BMPs
Areas draining to BMPs are those that could not be fully managed through LID Principles (DMA Types A through C) and will instead drain to an LID BMP and/or a Conventional Treatment BMP designed to manage water quality impacts from that area, and Hydromodification where necessary.

Complete Table C-5 to document which DMAs are classified as Areas Draining to BMPs Table C-5 Type ‘D’, Areas Draining to BMPs
DMA Name or ID BMP Name or ID Receiving Runoff from DMA DMA 1 BMP 1
DMA 2 BMP 2
Note: More than one DMA may drain to a single LID BMP; however, one DMA may not drain to more than one BMP.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
21 Section D: Implement LID BMPs
The Regional MS4 Permit requires the use of LID BMPs to provide retention or treatment of the DCV and includes a BMP hierarchy which requires Full Retention BMPs (Priority 1) to be considered before Biofiltration BMPs (Priority 2) and Flow-Through Treatment BMPs and Alternative Compliance BMPs (Priority 3). LID BMP selection must be based on technical feasibility and should be considered early in the site planning and design process. Use this section to document the selection of LID BMPs for each DMA.

Note that feasibility is based on the DMA scale and may vary between DMAs based on site conditions.

D.1 Full Infiltration Applicability
An assessment of the feasibility of utilizing full infiltration BMPs is required for all projects, except where it can be shown that site design LID principles fully retain the DCV (i.e., all DMAs are Type A, B, or C), or where Harvest and Use BMPs fully retain the DCV. Check the following box if applicable:

Site design LID principles or Tree Wells fully retain the DCV (i.e., all DMAs are Type A, B, or C), (Proceed to Section E).

If the above box remains unchecked, perform a site-specific evaluation of the feasibility of Infiltration BMPs using each of the applicable criteria identified in Chapter 2.3.3 of the SMR WQMP and complete the remainder of Section D.1.

Geotechnical Report
A Geotechnical Report or Phase I Environmental Site Assessment may be required by the Copermittee to confirm present and past site characteristics that may affect the use of Infiltration BMPs. In addition, the Copermittee, at their discretion, may not require a geotechnical report for small projects as described in Chapter 2 of the SMR WQMP. If a geotechnical report has been prepared, include it in Appendix 3. In addition, if a Phase I Environmental Site Assessment has been prepared, include it in Appendix 4.

Infiltration Feasibility
Table D-1 below is meant to provide a simple means of assessing which DMAs on your site support Infiltration BMPs and is discussed in the SMR WQMP in Chapter 2.3.3. Check the appropriate box for each question and then list affected DMAs as applicable. If additional space is needed, add a row below the corresponding answer.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
22 Table D-1 Infiltration Feasibility
Downstream Impacts (SMR WQMP Section 2.3.3.a)
Does the project site… YES NO
…have any DMAs where infiltration would negatively impact downstream water rights or other Beneficial Uses3? X If Yes, list affected DMAs:

Groundwater Protection (SMR WQMP Section 2.3.3.b)
Does the project site… YES NO
…have any DMAs with industrial, and other land uses that pose a high threat to water quality, which cannot be treated by Bioretention BMPs? Or have DMAs with active industrial process areas? X If Yes, list affected DMAs:
…have any DMAs with a seasonal high groundwater mark shallower than 10 feet? X If Yes, list affected DMAs:
…have any DMAs located within 100 feet horizontally of a water supply well? X If Yes, list affected DMAs:
…have any DMAs that would restrict BMP locations to within a 2:1 (horizontal: vertical) influence line extending from any septic leach line? X
If Yes, list affected DMAs:
…have any DMAs been evaluated by a licensed Geotechnical Engineer, or Environmental Engineer, who has concluded that the soils do not have adequate physical and chemical characteristics for the protection of groundwater, and has treatment provided by amended media layers in Bioretention BMPs been considered in evaluating this factor?
X
If Yes, list affected DMAs:

Public Safety and Offsite Improvements (SMR WQMP Section 2.3.3.c) Does the project site… YES NO
…have any areas identified by the geotechnical report as posing a public safety risk where infiltration of stormwater could have a negative impact, such as potential seepage through fill conditions? X
If Yes, list affected DMAs:

Infiltration Characteristics For LID BMPs (SMR WQMP Section 2.3.3.d) Does the project site… YES NO
…have measured infiltration rates of less than 2.4 inches / hour? Riverside County may allow measure rates as low as 0.8in/hr to support infiltration BMPs, if the Engineer believes infiltration is appropriate and sustainable. Mark no, if this is the case.

X
If Yes, list affected DMAs: All DMAs
Cut/Fill Conditions (SMR WQMP Section 2.3.3.e)
Does the project site… YES NO
…have significant cut and/or fill conditions that would preclude in-situ testing of infiltration rates at the final infiltration surface? X
If Yes, list affected DMAs:

Other Site-Specific Factors (SMR WQMP Section 2.3.3.f)
Does the project site… YES NO
…have DMAs where the geotechnical investigation discovered other site-specific factors that would preclude effective and/or safe infiltration? X
Describe here:

If you answered “Yes” to any of the questions above for any DMA, Infiltration BMPs that rely solely on infiltration should not be used for those DMAs and you should proceed to the assessment for Biofiltration BMPs below. Biofiltration BMPs that provide partial infiltration may still be feasible and should be assessed in Section D.2. Summarize concerns identified in the Geotechnical Report, if any, that resulted in a “YES” response above in the table below.
3 Such a condition must be substantiated by sufficient modeling to demonstrate an impact and would be subject to County of Riverside discretion. There is not a standardized method for assessing this criterion. Water rights evaluations should be site-specific.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
23 Table D-2 Geotechnical Concerns for Onsite Infiltration Type of Geotechnical Concern DMAs Feasible (By Name or ID) DMAs Infeasible (By Name or ID) Collapsible Soil N/A N/A
Expansive Soil N/A N/A
Slopes N/A N/A
Liquefaction N/A N/A
Low Infiltration Rate N/A All DMAs
Other N/A N/A
D.2 Biofiltration Applicability
This section should document the applicability of biofiltration BMPs for Type D DMAs that are not feasible for full infiltration BMPs. The key decisions to be documented in this section include:

1. Are biofiltration BMPs with partial infiltration feasible? a. Biofiltration BMPs must be designed to maximize incidental infiltration via a partial infiltration design unless it is demonstrated that this design is not feasible. b. These designs can be used at sites with low infiltration rates where other feasibility factors do not preclude incidental infiltration.

Document summary in Table D-3.

2. If not, what are the factors that require the use of biofiltration with no infiltration? This may include:
a. Geotechnical hazards
b. Water rights issues
c. Water balance issues
d. Soil contamination or groundwater quality issues
e. Very low infiltration rates (factored rates < 0.1 in/hr) f. Other factors, demonstrated to the acceptance of the local jurisdiction If this applies to any DMAs, then rationale must be documented in Table D-3.

3. Are biofiltration BMPs infeasible?
a. If yes, then provide a site-specific analysis demonstrating the technical infeasibility of all LID BMPs has been performed and is included in Appendix 5. If you plan to submit an analysis demonstrating the technical infeasibility of LID BMPs, request a pre-submittal meeting with the Copermittee with jurisdiction over the Project site to discuss this option. Proceed below.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
24 Table D-3 Evaluation of Biofiltration BMP Feasibility DMA ID
Is Partial/
Incidental
Infiltration
Allowable?
(Y/N)
Basis for Infeasibility of Partial Infiltration (provide summary and include supporting basis if partial infiltration not feasible) DMA 1 N N/A. Overall site has low infiltration rates
DMA 2 N N/A. Overall site has low infiltration rates
Proprietary Biofiltration BMP Approval Criteria
Does the Co-Permittee allow Proprietary BMPs as an equivalent to Biofiltration, if specific criteria is met? Yes or No, if no skip to Section F to document your alternative compliance measures.

If the project will use proprietary BMPs as biofiltration BMPs, then this section and Appendix 5 shall be completed to document that the proprietary BMPs are selected in accordance with Section 2.3.6 of the SMR WQMP and County requirements. Proprietary Biofiltration BMPs must meet both of the following approval criteria:

1. Demonstrate equivalency to Biofiltration by completing the BMP Design worksheet and Proprietary Biofiltration Criteria, which is found in Appendix 5, including all supporting documentation, and

2. Obtain Co-Permittee concurrence for the long term Operation and Maintenance Plan for the proprietary BMP. The Co-Permittee has the sole discretion to allow or reject Proprietary BMPs, especially if they will be maintained publically through a CFD, CSA, or L&LMD.

Add additional rows to Table D-4 to document approval criteria are met for each type of BMP proposed.

Table D-4 Proprietary BMP Approval Requirement Summary
Proposed Proprietary
Biofiltration BMP Approval Criteria Notes/Comments
Modular Wetland
System
(Contech)
BMP Design worksheets and Proprietary
Biofiltration Criteria are completed in
Appendix 5
Yes or No
Proposed BMP has an active TAPE GULD
Certification for the project pollutants of
concern4 or equivalent 3rd party
demonstrated performance.

Yes or No
Is there any media or cartridge required to
maintain the function of the BMP solesourced or proprietary in any way? If yes, obtain explicit approval by the Agency.

Potentially full replacement costs to a nonproprietary BMP needs to be considered.

Yes or No
If yes, provide the date of concurrence
from the Co-Permittee.

Insert date here
The BMP includes biological features
including vegetation supported by
engineered or other growing media.

City of Murrieta requires biological
features to be included for proposed
MWS units.
4 Use Table F-1, F-2, and F-3 to identify and document the pollutants of concern and include these tables in Appendix 5.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
25 D.3 Feasibility Assessment Summaries
From the Infiltration, Biofiltration with Partial Infiltration and Biofiltration with No Infiltration Sections above, complete Table D-5 below to summarize which LID BMPs are technically feasible, and which are not, based upon the established hierarchy.

Table D-5 LID Prioritization Summary Matrix
DMA Name/ID
LID
Principles
or Tree
Wells
LID BMP Hierarchy
No LID (Alternative

1. Infiltration Compliance)

2. Biofiltration
with Partial
Infiltration*

3. Biofiltration
with No
Infiltration*
DMA 1
DMA 2
*Includes Proprietary Biofiltration, if accepted by the Co-Permittee.

For those DMAs where LID BMPs are not feasible, provide a narrative in Table D-6 below summarizing why they are not feasible, include your technical infeasibility criteria in Appendix 5, and proceed to Section F below to document Alternative Compliance measures for those DMAs. Recall that each proposed DMA must pass through the LID BMP hierarchy before alternative compliance measures may be considered.

This is based on the clarification letter titled “San Diego Water Board’s Expectations of Documentation to Support a Determination of Priority Development Project Infiltration Infeasibility” (April 28, 2017, Via email from San Diego Regional Water Quality Control Board to San Diego County Municipal Storm Water Copermittees5).

Table D-6 Summary of Infeasibility Documentation
Question
Narrative Summary (include reference to applicable
appendix/attachment/report, as applicable)
a) When in the entitlement process
did a geotechnical engineer analyze
the site for infiltration feasibility?
A Geotechnical investigation was performed in the by
Leighton Consulting, Inc., dated July 12, 2023.
b) When in the entitlement process
were other investigations
conducted (e.g., groundwater
quality, water rights) to evaluate
infiltration feasibility?
The Geotechnical report written Leighton Consulting, Inc, Inc, on July 12, 2023 stated that groundwater was not
encountered in their exploration borings of 21.5 ft below ground surface.
c) What was the scope and results of
testing, if conducted, or rationale
for why testing was not needed to
reach findings?
Boring logs were created and infiltration testing was
provided which showed infeasible infiltration rates.
d) What public health and safety
requirements affected infiltration
locations?
N/A
e) What were the conclusions and
recommendations of the
geotechnical engineer and/or other
The Geotechnical report written Leighton Consulting, Inc, Inc, recommended to use the lowest infiltration rate in the 5 http://www.projectcleanwater.org/download/pdp-infiltration-infeasibility/ Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
26 professional responsible for other
investigations?
design. This rate of 0.01 in/hr is deemed infeasible for infiltration or partial infiltration.
f) What was the history of design
discussions between the permittee
and applicant for the proposed
project, resulting in the final design
determination related locations
feasible for infiltration?
N/A
g) What site design alternatives were
considered to achieve infiltration or
partial infiltration on site?
No other alternatives were considered.
h) What physical impairments (i.e.,
fire road egress, public safety
considerations, utilities) and public
safety concerns influenced site
layout and infiltration feasibility?
N/A
i) What LID Principles (site design
BMPs) were included in the project
site design?
Flow based Modular Wetland Systems
D.4 LID BMP Sizing
Each LID BMP must be designed to ensure that the DCV will be captured by the selected BMPs with no discharge to the storm drain or surface waters during the DCV size storm. Infiltration BMPs must at minimum be sized to capture the DCV to achieve pollutant control requirements.

Biofiltration BMPs must at a minimum be sized to:
• Treat 1.5 times the DCV not reliably retained on site using a volume-base or flow-based sizing method, or
• Include static storage volume, including pore spaces and pre-filter detention volume, at least 0.75 times the portion of the DCV not reliably retained on site.

First, calculate the DCV for each LID BMP using the VBMP worksheet in Appendix F of the LID BMP Design Handbook. Second, design the LID BMP to meet the required VBMP using the methods included in Section 3 of the LID BMP Design Handbook. Utilize the worksheets found in the LID BMP Design Handbook or consult with the Copermittee to assist you in correctly sizing your LID BMPs. Use Table D-7 below to document the DCV each LID BMP. Provide the completed design procedure sheets for each LID BMP in Appendix 6. You may add additional rows to the table below as needed.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
27 Table D-7 DCV Calculations for LID BMPs
DMA
Type/ID
DMA
(ac)
PostProject
Surface
Type
Effective
Impervious
Fraction, If
DMA
Runoff
Factor
BMP-1 (8’x12’)
(Flow Based Modular Wetland
System)
[A] [B] [C]
DMA
1,3,4

1.24 Mixed
Surfaces

0.81 0.61
Design
Storm
Intensity
(in/hr) QBMP (cfs)
Proposed
Flow on
Plans (cfs)
AT =
54,230 0.2 0.2 0.35
DMA
Type/ID
DMA
(ac)
PostProject
Surface
Type
Effective
Impervious
Fraction, If
DMA
Runoff
Factor BMP-2 (Double 8’x16’)
(Flow Based Modular Wetland
System) [A] [B] [C]
DMA 2,5 3.57 Mixed
Surfaces

0.84 0.65
Design
Storm
Intensity
(in/hr) QBMP (cfs)
Proposed
Flow on
Plans (cfs)
AT =
155,880 0.2 0.5 0.92
*Note that DMAs 3-4, and 5 consists of primarily landscaped areas around the perimeter of the site that cannot be feasibly conveyed to the MWS units. These MWS units, however, have been conservatively sized to include these areas to provide additional treatment capacity. These areas will be reviewed and MWS units resized, if necessary, during final design. [B], [C] is obtained as described in Section 2.6.1.b of the SMR WQMP [E] is obtained from Exhibit A in the SMR WQMP
[G] is obtained from a design procedure sheet, such as in LID BMP Design Handbook and placed in Appendix 6.

Complete Table D-8 below to document the Design Capture Volume and the Proposed Volume for each LID BMP. You can add rows to the table as needed. Alternatively, the Santa Margarita Hydrology Model (SMRHM) can be used to size LID BMPs to address the DCV and, if applicable, to size Hydrologic Control BMPs to meet the Hydrologic Performance Standard described in the SMR WQMP, as identified in Section E.

Table D-8 LID BMP Sizing
BMP Name
/ ID
DMA No. BMP Type /
Description
Water quality
flow rate (cfs)
Biofiltration
flow rate (cfs)
Proposed flow
rate (cfs)
BMP 1 DMA 1 Biofiltration Modular
Wetlands System 8x12

0.2 0.23 0.35
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
28 BMP 2 DMA 2 Biofiltration Modular
Wetlands System (2)
8x16

0.5 0.70 0.92
BMP 1 is a biofiltration system comprised of a MWS-L-8-12. DMA 1 is tributary to BMP 1. BMP 2 is a biofiltration system comprised of two MWS-L-8-16 units. DMA 2 is tributary to BMP 2. Both biofiltration systems are flows based and were sized using 1.5 times the design flow rate. See table F-4 for design flow rate calculations. Both BMPs are located above ground in the proposed landscape area. Upstream of each MWS is an underground detention system provided to mitigate flows.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
29 Section E: Implement Hydrologic Control BMPs and Sediment Supply BMPs
See Appendix 7 for additional required information.

If a completed Table 1.2 demonstrates that the project is exempt from Hydromodification Performance Standards, specify N/A and proceed to Section G.

N/A Project is Exempt from Hydromodification Performance Standards.

If a PDP is not exempt from hydromodification requirements than the PDP must satisfy the requirements of the performance standards for hydrologic control BMPs and Sediment Supply BMPs. The PDP may choose to satisfy hydrologic control requirements using onsite or offsite BMPs (i.e. Alternative Compliance). Sediment supply requirements cannot be met via alternative compliance. If N/A is not selected above, select one of the two options below and complete the applicable sections.

Project is Not Hydromodification Exempt and chooses to implement Hydrologic Control and Sediment Supply BMPs Onsite (complete Section E).

Project is Not Hydromodification Exempt and chooses to implement Hydrologic Control Requirements using Alternative Compliance (complete Section F). Selection of this option must be approved by the Copermittee.

Addressing hydromodification requirements: the project site is currently located on a portion of undeveloped land which is labeled “potentially not exempt” per the Santa Margarita Region Hydromodification Plan. However, runoff from this portion of land drains into an existing gravel channel as part of the Master Plan of Drainage, is directed through a shallow storm drain line which discharges overland approximately 0.5 miles south of the site and runs directly into the Murrieta Creek Channel. The portion of the Murrieta Creek where this runoff discharges is currently labeled as “potential exempt” from hydromodification requirements. As stated by the Santa Margarita Region Hydromodification Management Plan, Murrieta Creek is exempt from Hydromodification Requirements if the discharge location is located downstream of “850 feet upstream of Hawthorn Street.” The CarMax project site is located within a portion of land which discharges 0.5 miles south to a point within the exempt reaches of Murrieta Creek. Additional hydromodification calculations using the Clear Creek program will be performed as a check but not implemented in the overall site design.

E.1 Hydrologic Control BMP Selection
Capture of the DCV and achievement of the Hydrologic Performance Standard may be met by combined and/or separate structural BMPs. The user should consider the full suite of Hydrologic Control BMPs to manage runoff from the post-development condition and meet the Hydrologic Performance Standard identified in this section.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
30 For the Preliminary WQMP, in lieu of preparing detailed routing calculations, the basin size may be estimated as the difference in volume between the pre-development and post-development hydrograph for the 10-year 24-hour storm event plus the Vbmp. This does not relieve the engineer of the responsibility for meeting the full Hydrologic Control requirements during final design.

The Hydrologic Performance Standard consists of matching or reducing the flow duration curve of postdevelopment conditions to that of pre-existing, naturally occurring conditions, for the range of geomorphically significant flows (the low flow threshold runoff event up to the 10-year runoff event). 10% of the 2-year runoff event can be used for the low flow threshold without any justification. Higher low flow thresholds can be used with site-specific analysis, see Section 2.6.2.b of the WQMP guidance document. Select each of the hydrologic control BMP types that are applied to meet the above performance standard on the site.

LID principles as defined in Section 3.2 of the SMR WQMP, including Tree Wells.

Structural LID BMPs that may be modified or enlarged, if necessary, beyond the DCV.

Structural Hydrologic Control BMPs that are distinct from the LID BMPs above. The LID BMP Design Handbook provides information not only on Hydrologic Control BMP design, but also on BMP design to meet the combined LID requirement and Hydrologic Performance Standard. The Handbook specifies the type of BMPs that can be used to meet the Hydrologic Performance Standard.

E.2 Hydrologic Control BMP Sizing
Hydrologic Control BMPs must be designed to ensure that the flow duration curve of the postdevelopment DMA will not exceed that of the pre-existing, naturally occurring, DMA for the range of geomorphically significant flows. Using SMRHM, (or another acceptable continuous simulation model if approved by the Copermittee) the applicant shall demonstrate that the performance of the Hydrologic Control BMPs complies with the Hydrologic Performance Standard. Complete Table E-1 below and identify, for each DMA, the type of Hydrologic Control BMP, if the SMRHM model confirmed the management (Identified as “passed” in SMRHM), the total volume capacity of the Hydrologic Control BMP, the Hydrologic Control BMP footprint at top floor elevation, and the drawdown time of the Hydrologic Control BMP. SMRHM summary reports should be documented in Appendix 7. Refer to the SMRHM Guidance Document for additional information on SMRHM. You can add rows to the table as needed.

Table E-1 Hydrologic Control BMP Sizing
BMP
Name / ID
DMA
No.

BMP Type /
Description
SMRHM*
Passed
BMP
Volume
(ac-ft)
BMP
Footprint (ac)
Drawdown
time (hr)
DET-1 1 Underground
Detention

0.42 0.003 5 days
DET-2 2 Underground
Detention

1.30 0.009 5 days
A vector control plan will be developed during final design to address longer drawdown times.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
31 *Or other continuous simulation model, compliant with the WQMP and Permit. If Tree Wells are proposed for some or all of the project, check the box for Tree Wells in Section E.1 and enter each Tree Well DMA in Table E-1 above for the BMP Name/ID, DMA No. and BMP Type/Description. For Tree Wells, leave SMRHM* Passed Column and the columns to the left blank.

If a bioretention BMP with capped underdrain is used and hydromodification requirements apply, then sizing calculations must demonstrate that the BMP meets flow duration control criteria with the underdrain capped and uncapped. Both calculations must be included.

E.3 Implement Sediment Supply BMPs
The sediment supply performance standard applies to PDPs for which hydromodification applied that have the potential to impact Potential Critical Coarse Sediment Yield Areas. Refer to Exhibit G-1 of the WQMP Guidance Document to determine if there are onsite Potential Critical Coarse Sediment Yield Areas (based on on-going WMAA analysis) or Potential Sediment Source Areas(sites added through the Regional Board review process). Select one of the two options below and include the Potential Critical Coarse Sediment Yield Area Exhibit showing your project location in Appendix 7.

There are no mapped Potential Critical Coarse Sediment Yield Areas or Potential Sediment Source Areas on the site. Include a copy of Exhibit G - CCSY & PSS Areas in Appendix 7, with the project location marked. If the project is outside of the “Potential Critical Coarse Sediment Yield Areas and Potential Sediment Source Areas” then check this box. The Sediment Supply Performance Standard is met with no further action is needed.

There are mapped Potential Critical Coarse Sediment Yield Areas or Potential Sediment Source Areas on the site, the Sediment Supply Performance Standard will be met through Option 1 (E.3.1) or Option 2 (E.3.2) below.

E.3.1 Option 1: Avoid Potential Critical Coarse Sediment Yield Areas and Potential Sediment Source Areas
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32 Section F: Alternative Compliance
Alternative Compliance may be used to achieve compliance with pollutant control and/or hydromodification requirements for a given PDP. Alternative Compliance may be used under two scenarios, check the applicable box if the PDP is proposing to use Alternative Compliance to satisfy all or a portion of the Pollutant Control and/or Hydrologic Control requirements (but not sediment supply requirements)
If it is not feasible to fully implement Infiltration or Biofiltration BMPs at a PDP site, Flow-Through Treatment Control BMPs may be used to treat pollutants contained in the portion of DCV not reliably retained on site and Alternative Compliance measures must also be implemented to mitigate for those pollutants in the DCV that are not retained or removed on site prior to discharging to a receiving water.

Alternative Compliance is selected to comply with either pollutant control or hydromodification flow control requirements even if complying with these requirements is potentially feasible on-site. If such voluntary Alternative Compliance is implemented, Flow-Through Treatment Control BMPs must still be used to treat those pollutants in the portion of the DCV not reliably retained on site prior to discharging to a receiving water.

Refer to Section 2.7 of the SMR WQMP and consult the Local Jurisdiction for currently available Alternative Compliance pathways. Coordinate with the Copermittee if electing to participate in Alternative Compliance and complete the sections below to document implementation of the FlowThrough BMP component of the program.

F.1 Identify Pollutants of Concern
The purpose of this section is to help you appropriately plan for mitigating your Pollutants of Concern in lieu of implementing LID BMPs and to document compliance and.

Utilize Table A-1 from Section A, which noted your project’s Receiving Waters, to identify impairments for Receiving Waters (including downstream receiving waters) by completing Table F-1. Table F-1 includes the watersheds identified as impaired in the Approved 2010 303(d) list; check box corresponding with the PDP’s receiving water. The most recent 303(d) lists are available from the State Water Resources Control Board website:
https://www.waterboards.ca.gov/water_issues/programs/tmdl/integrated2010.shtml).https://www.wa terboards.ca.gov/water_issues/programs/tmdl/integrated2010.shtml.

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33 Table F-1 Summary of Approved 2010 303(d) listed waterbodies and associated pollutants of concern for the Riverside County SMR Region and downstream waterbodies.

Water BodyNutrients
1 Metals
2 ToxicityBacteria and PathogensPesticides and HerbicidesSulfateTotal Dissolved Solids De Luz Creek X X X
Long Canyon Creek X X X
Murrieta Creek X X X X
Redhawk Channel X X X X X
Santa Gertudis Creek X X X X
Santa Margarita Estuary X
Santa Margarita River (Lower) X X
Santa Margarita River (Upper) X X
Temecula Creek X X X X X
Warm Springs Creek X X X X
1 Nutrients include nitrogen, phosphorus and eutrophic conditions caused by excess nutrients. 2 Metals includes copper, iron, and manganese.

Use Table F-2 to identify the pollutants identified with the project site. Indicate the applicable PDP Categories and/or Project Features by checking the boxes that apply. If the identified General Pollutant Categories are the same as those listed for your Receiving Waters, then these will be your Pollutants of Concern; check the appropriate box or boxes in the last row.

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34 Table F-2 Potential Pollutants by Land Use Type
Priority Development
Project Categories and/or
Project Features (check those
that apply)
General Pollutant Categories
Bacterial
Indicators Metals Nutrients Pesticides
Toxic
Organic
Compounds
Sediments Trash &
Debris
Oil &
Grease
Total
Dissolved
Solids
Sulfate
Detached Residential
Development P N P P N P P P N N
Attached Residential
Development P N P P N P P P
(2) N N
Commercial/Industrial
Development P
(3) P(7) P(1) P(1) P P(1) P P N N
Automotive Repair
Shops N P N N P
(4, 5) N P P N N
Restaurants
(>5,000 ft2)

P N N P
(1) N N P P N N
Hillside Development
(>5,000 ft2)

P N P P N P P P N N
Parking Lots
(>5,000 ft2)
P
(6) P(7) P(1) P(1) P(4) P P P N N
Streets, Highways, and
Freeways P
(6) P(7) P(1) P(1) P(4) P P P N N
Retail Gasoline Outlets N P
(7) N N P(4) N P P N N
Project Priority
Pollutant(s) of Concern
P = Potential
N = Not Potential
(1) A potential Pollutant if non-native landscaping exists or is proposed onsite; otherwise not expected (2) A potential Pollutant if the project includes uncovered parking areas; otherwise not expected (3) A potential Pollutant is land use involving animal waste products; otherwise not expected (4) Including petroleum hydrocarbons
(5) Including solvents
(6) Bacterial indicators are routinely detected in pavement runoff (7) A potential source of metals, primarily copper and zinc. Iron, magnesium, and aluminum are commonly found in the environment and are commonly associated with soils, but are not primarily of anthropogenic stormwater origin in the municipal environment.

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35 F.2 Treatment Control BMP Selection
Treatment Control BMPs typically provide proprietary treatment mechanisms to treat potential Pollutants in runoff, but do not sustain significant biological processes. Treatment Control BMPs must be selected to address the Project Priority Pollutants of Concern (identified above) and meet the acceptance criteria described in Section 2.3.7 of the SMR WQMP. Documentation of acceptance criteria must be included in Appendix 6. In addition, ensure that proposed Treatment Control BMPs are properly identified on the WQMP Site Plan in Appendix 1.

Table F-3 Treatment Control BMP Selection
Selected Treatment Control BMP
Name or ID1
Priority Pollutant(s) of
Concern to Mitigate2
Removal Efficiency
Percentage3
1 Treatment Control BMPs must not be constructed within Receiving Waters. In addition, a proposed Treatment Control BMP may be listed more than once if they possess more than one qualifying pollutant removal efficiency. 2 Cross Reference Table E.1 above to populate this column. 3 As documented in a Copermittee Approved Study and provided in Appendix 6.

F.3 Sizing Criteria
Utilize Table F-4 below to appropriately size flow-through BMPs to the DCV, or Design Flow Rate, as applicable. Please reference Chapter 3.5.1 of the SMR WQMP for further information.

Table F-4 Treatment Control BMP Sizing
DMA
Type/ID
DMA
Area
(square
feet)
PostProject
Surface
Type
Effective
Impervious
Fraction, If
DMA
Runoff
Factor
DMA
Areas x
Runoff
Factor
[A] [B] [C] [A] x [C]
Design
Storm
(in)
Design Flow
Rate (cfs)
Flow Rate
Provided
(cfs)
AT Σ
[B], [C] is obtained as described in Section 2.6.1.b from the SMR WQMP [E] either 0.2 inches or 2 times the 85th percentile hourly rainfall intensity [G] = 43,560
[B], [C] is obtained as described in Section 2.6.1.b from the SMR WQMP [E] either 0.2 inches or 2 times the 85th percentile hourly rainfall intensity [G] = 43,560
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36 F.4 Hydrologic Performance Standard – Alternative Compliance Approach
Not Applicable.

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37 Section G: Implement Trash Capture BMPs
The Santa Margarita Regional Board has required Full Trash Capture compliance thru Order No. R9- 2017-007. For the Santa Margarita Watershed, the County is requiring Track 1 full trash capture compliance for projects proposing the following uses as part of their development after December 3, 2018.
• High-density residential: all land uses with at least ten (10) developed dwelling units/acre. • Industrial: land uses where the primary activities on the developed parcels involve product manufacture, storage, or distribution (e.g., manufacturing businesses, warehouses, equipment storage lots, junkyards, wholesale businesses, distribution centers, or building material sales yards).
• Commercial: land uses where the primary activities on the developed parcels involve the sale or transfer of goods or services to consumers (e.g., business or professional buildings, shops, restaurants, theaters, vehicle repair shops, etc.).
• Mixed urban: land uses where high-density residential, industrial, and/or commercial land uses predominate collectively (i.e., are intermixed).
• Public transportation stations: facilities or sites where public transit agencies’ vehicles load or unload passengers or goods (e.g., bus stations and stops).

Riverside County Maintenance is generally supportive of United Storm Water – Connector Pipe Screens or equivalent. Equivalent systems or alternative designs shall be on the State of California Approved Trash Capture Device List and requires approval by the Transportation Department for maintenance.

Riverside County is developing Trash Capture Device Standards, which are expected to be added to the Transportation Plan Check Policies and Guidelines when available. Design calculations are not expected to be required if the project uses standard sizes per the County’s Trash Capture Device Standards. Until the Trash Capture Device Standards are available and the project uses standard sizes, the project shall complete the following tables and furnish hydraulic analysis calculating the flowrate in the catch basin does not exceed the flowrate capacity of the trash capture device in a fully clogged condition.

Trash Capture BMPs may be applicable to Type 'D' DMAs, as defined in Section 2.3.4 of the SMR WQMP.

Trash Capture BMPs are designed to treat QTRASH, the runoff flow rate generated during the 1-year 1- hour precipitation depth. Utilize Table G-1 to size Trash Capture BMP. Refer to Table G-2 to determine the Trash Capture Design Storm Intensity (E).

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38 Table G-1 Sizing Trash Capture BMPs
DMA
Type/ID
DMA
Area
(square
feet)
Post-Project
Surface
Type
Effective
Impervious
Fraction, If
DMA
Runoff
Factor
DMA
Areas x
Runoff
Factor FlexStorm Inserts
[A] [B] [C] [A] x [C]
DMA 1 54,230 Concrete or
Asphalt
1 0.89 49,265
Trash Capture
Design Storm
Intensity (in)
Trash Capture Design
Flow Rate (cfs)
DMA 2 155,880 Mixed
Surfaces

0.84 0.65 101,322
AT
=210,110
Σ=
150,587 0.47 [F] = 1.6
[B], [C] is obtained as described in Section 2.6.1.b from the SMR WQMP [G] = 43,560
Table G-2 Approximate precipitation depth/intensity values for calculation of the Trash Capture Design Storm City 1-year 1-hour Precipitation
Depth/Intensity (inches/hr)
Murrieta 0.47
Temecula 0.50
Wildomar 0.37
Use Table G-3 to summarize and document the selection and sizing of Trash Capture BMPs.

Table G-3 Trash Capture BMPs
BMP Name /
ID
DMA
No(s) BMP Type / Description
Required Trash
Capture Flowrate
(cfs)
Provided Trash
Capture Flowrate
(cfs)1
FlexStorm
inserts
DMA 1
and 2
FlexStorm Inserts 1.6 2.4
1 For connector pipe screens, the Trash Capture Flowrate shall be based on a fully clogged condition for the screen, where the water level is at the top of the screen. Then determined the Flowrate based on weir equation (Qweir = C x L x H^(2/3), where C = 3.4). The height used to calculate the weir flow rate shall maintain a 6” freeboard to the invert of the catch basin opening at the road. This analysis is meant to replicate the hydraulic analysis used in the County’s Full Trash Capture Device Standards.

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39 Section H: Source Control BMPs
Section H need only be completed at the Preliminary WQMP phase if source control is critical to the project successfully handling the anticipated pollutants.

Source Control BMPs include permanent, structural features that may be required in your Project plans, such as roofs over and berms around trash and recycling areas, and Operational BMPs, such as regular sweeping and “housekeeping,” that must be implemented by the site’s occupant or user. The Maximum Extent Practicable (MEP) standard typically requires both types of BMPs. In general, Operational Source Control BMPs cannot be substituted for a feasible and effective Structural Source Control BMP. Complete checklist below to determine applicable Source Control BMPs for your site.

Project-Specific WQMP Source Control BMP Checklist
All development projects must implement Source Control BMPs. Source Control BMPs are used to minimize pollutants that may discharge to the MS4. Refer to Chapter 3 (Section 3.8) of the SMR WQMP for additional information. Complete Steps 1 and 2 below to identify Source Control BMPs for the project site.

STEP 1: IDENTIFY POLLUTANT SOURCES
Review project site plans and identify the applicable pollutant sources. “Yes” indicates that the pollutant source is applicable to project site. “No” indicates that the pollutant source is not applicable to project site.

Yes No Storm Drain Inlets Yes No Outdoor storage areas
Yes No Floor Drains Yes No Material storage areas
Yes No Sump Pumps Yes No Fueling areas
Yes No Pets Control/Herbicide Application Yes No Loading Docks Yes No Food Service Areas Yes No Fire Sprinkler Test/Maintenance water Yes No Trash Storage Areas Yes No Plazas, Sidewalks and Parking Lots Yes No Industrial Processes Yes No Pools, Spas, Fountains and other water features
Yes No Vehicle and Equipment Cleaning and
Maintenance/Repair Areas
STEP 2: REQUIRED SOURCE CONTROL BMPS
List each Pollutant source identified above in column 1 and fill in the corresponding Structural Source Control BMPs and Operational Control BMPs by referring to the Stormwater Pollutant Sources/Source Control Checklist included in Appendix 8. The resulting list of structural and operational source control BMPs must be implemented as long as the associated sources are present on the project site. Add additional rows as needed.

Pollutant Source Structural Source Control BMP Operational Source Control BMP Storm Drain Inlets Mark inlets with “only rain down the storm drain”
Maintain and periodically repaint of
replace inlet markings. See CASQA
Fact Sheet SC-44.

Plazas sidewalks and Parking Lots Street Sweeping Sweep sidewalks and parking lots regularly to prevent accumulation of
litter and debris.

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40 Section I: Coordinate Submittal with Other Site Plans For Final WQMPs, populate Table I-1 below to assist the plan checker in an expeditious review of your project. During construction and at completion, County of Riverside inspectors will verify the installation of BMPs against the approved plans. The first two columns will contain information that was prepared in previous steps, while the last column will be populated with the corresponding plan sheets. This table is to be completed with the submittal of your final Project-Specific WQMP.

Table I-1 Construction Plan Cross-reference
BMP No. or ID BMP Identifier and Description Corresponding Plan Sheet(s) BMP 1 biofiltration unit (MWS) WQMP Exhibit
BMP 2 biofiltration unit (MWS) WQMP Exhibit
Note that the updated table — or Construction Plan WQMP Checklist — is only a reference tool to facilitate an easy comparison of the construction plans to your Project-Specific WQMP. The Copermittee with jurisdiction over the Project site can advise you regarding the process required to propose changes to the approved Project-Specific WQMP.

Use Table I-2 to identify other applicable permits that may impact design of the site. If yes is answered to any of the items below, the Copermittee may require proof of approval/coverage from those agencies as applicable including documentation of any associated requirements that may affect this Project-Specific WQMP.

Table I-2 Other Applicable Permits
Agency Permit Required
State Department of Fish and Game, 1602 Streambed Alteration Agreement Y N State Water Resources Control Board, Clean Water Act Section 401 Water Quality Certification Y N US Army Corps of Engineers, Clean Water Act Section 404 Permit Y N US Fish and Wildlife, Endangered Species Act Section 7 Biological Opinion Y N Statewide Construction General Permit Coverage Y N
Statewide Industrial General Permit Coverage Y N
Western Riverside MSHCP Consistency Approval (e.g., JPR, DBESP) Y N Other (please list in the space below as required) Y N
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41 Section J: Operation, Maintenance and Funding
Applicant is required to state the intended responsible party for BMP Operation, Maintenance and Funding at the Preliminary WQMP phase. The remaining requirements as outlined above are required for Final WQMP only.

The Copermittee with jurisdiction over the Project site will periodically verify that BMPs on your Project are maintained and continue to operate as designed. To make this possible, the Copermittee will require that you include in Appendix 9 of this Project-Specific WQMP:

1. A means to finance and implement maintenance of BMPs in perpetuity, including replacement cost.

2. Acceptance of responsibility for maintenance from the time the BMPs are constructed until responsibility for operation and maintenance is legally transferred. A warranty covering a period following construction may also be required.

3. An outline of general maintenance requirements for the Stormwater BMPs you have selected.

4. Figures delineating and designating pervious and impervious areas, location, and type of Stormwater BMP, and tables of pervious and impervious areas served by each facility. Geolocating the BMPs using a coordinate system of latitude and longitude is recommended to help facilitate a future statewide database system.

5. A separate list and location of self-retaining areas or areas addressed by LID Principles that do not require specialized Operations and Maintenance or inspections but will require typical landscape maintenance as noted in Chapter 5, in the SMR WQMP. Include a brief description of typical landscape maintenance for these areas.

The Copermittee with jurisdiction over the Project site will also require that you prepare and submit a detailed BMP Operation and Maintenance Plan that sets forth a maintenance schedule for each of the BMPs built on your site. An agreement assigning responsibility for maintenance and providing for inspections and certification may also be required.

Details of these requirements and instructions for preparing a BMP Operation and Maintenance Plan are in Chapter 5 of the SMR WQMP.

Maintenance Mechanism: Owner to reference educational materials provided within this report for maintenance recommendations and procedures.

Will the proposed BMPs be maintained by a Homeowners’ Association (HOA) or Property Owners Association (POA)?
Y N
Include your Operation and Maintenance Plan and Maintenance Mechanism in Appendix 9, see Appendix 9 for additional instructions. Additionally, include all pertinent forms of educational materials for those personnel that will be maintaining the proposed BMPs within this Project-Specific WQMP in Appendix 10.

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42 Section K: Acronyms, Abbreviations and Definitions
Regional MS4 Permit Order No. R9-2013-0001 as amended by Order No. R9-2015-0001 and Order No. R9-2015-0100 an NPDES Permit issued by the San Diego Regional Water Quality Control Board.

Applicant Public or private entity seeking the discretionary approval of new or replaced improvements from the Copermittee with jurisdiction over the project site. The Applicant has overall responsibility for the implementation and the approval of a Priority Development Project. The WQMP uses consistently the term “user” to refer to the applicant such as developer or project proponent.

The WQMP employs also the designation “user” to identify the Registered Professional Civil Engineer responsible for submitting the Project-Specific WQMP, and designing the required BMPs.

Best Management
Practice (BMP)
Defined in 40 CFR 122.2 as schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to prevent or reduce the pollution of waters of the United States. BMPs also include treatment requirements, operating procedures and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw material storage. In the case of municipal storm water permits, BMPs are typically used in place of numeric effluent limits.

BMP Fact Sheets BMP Fact Sheets are available in the LID BMP Design Handbook.

Individual BMP Fact Sheets include sitting considerations, and design and sizing guidelines for seven types of structural BMPs (infiltration basin, infiltration trench, permeable pavement, harvest-and-use, bioretention, extended detention basin, and sand filter).

California
Stormwater Quality
Association (CASQA)
Publisher of the California Stormwater Best Management Practices Handbooks, available at
www.cabmphandbooks.com.

Conventional
Treatment Control
BMP
A type of BMP that provides treatment of stormwater runoff.

Conventional treatment control BMPs, while designed to treat particular Pollutants, typically do not provide the same level of volume reduction as LID BMPs, and commonly require more specialized maintenance than LID BMPs. As such, the Regional MS4 Permit and this WQMP require the use of LID BMPs wherever feasible, before Conventional Treatment BMPs can be considered or implemented.

Copermittees The Regional MS4 Permit identifies the Cities of Murrieta, Temecula, and Wildomar, the County, and the District, as Copermittees for the SMR.

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43 County The abbreviation refers to the County of Riverside in this document.

CEQA California Environmental Quality Act - a statute that requires state and local agencies to identify the significant environmental impacts of their actions and to avoid or mitigate those impacts, if feasible.

CIMIS California Irrigation Management Information System - an integrated network of 118 automated active weather stations all over California managed by the California Department of Water Resources.

CWA Clean Water Act - is the primary federal law governing water pollution. Passed in 1972, the CWA established the goals of eliminating releases of high amounts of toxic substances into water, eliminating additional water pollution by 1985, and ensuring that surface waters would meet standards necessary for human sports and recreation by 1983.

CWA Section 402(p) is the federal statute requiring NPDES permits for discharges from MS4s.

CWA Section 303(d)
Waterbody
Impaired water in which water quality does not meet applicable water quality standards and/or is not expected to meet water quality standards, even after the application of technology based pollution controls required by the CWA. The discharge of urban runoff to these water bodies by the Copermittees is significant because these discharges can cause or contribute to violations of applicable water quality standards.

Design Storm The Regional MS4 Permit has established the 85th percentile, 24- hour storm event as the "Design Storm". The applicant may refer to Exhibit A to identify the applicable Design Storm Depth (D85) to the project.

DCV Design Capture Volume (DCV) is the volume of runoff produced from the Design Storm to be mitigated through LID Retention BMPs, Other LID BMPs and Volume Based Conventional
Treatment BMPs, as appropriate.

Design Flow Rate The design flow rate represents the minimum flow rate capacity that flow-based conventional treatment control BMPs should treat to the MEP, when considered.

DCIA Directly Connected Impervious Areas - those impervious areas that are hydraulically connected to the MS4 (i.e. street curbs, catch basins, storm drains, etc.) and thence to the structural BMP without flowing over pervious areas.

Discretionary
Approval
A decision in which a Copermittee uses its judgment in deciding whether and how to carry out or approve a project.

District Riverside County Flood Control and Water Conservation District.

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44 DMA A Drainage Management Area - a delineated portion of a project site that is hydraulically connected to a common structural BMP or conveyance point. The Applicant may refer to Section 3.3 for further guidelines on how to delineate DMAs.

Drawdown Time Refers to the amount of time the design volume takes to pass through the BMP. The specified or incorporated drawdown times are to ensure that adequate contact or detention time has occurred for treatment, while not creating vector or other nuisance issues. It is important to abide by the drawdown time requirements stated in the fact sheet for each specific BMP.

Effective Area Area which 1) is suitable for a BMP (for example, if infiltration is potentially feasible for the site based on infeasibility criteria, infiltration must be allowed over this area) and 2) receives runoff from impervious areas.

ESA An Environmental Sensitive Area (ESA) designates an area "in which plants or animals life or their habitats are either rare or especially valuable because of their special nature or role in an ecosystem and which would be easily disturbed or degraded by human activities and developments". (Reference: California Public Resources Code § 30107.5).

ET Evapotranspiration (ET) is the loss of water to the atmosphere by the combined processes of evaporation (from soil and plant surfaces) and transpiration (from plant tissues). It is also an indicator of how much water crops, lawn, garden, and trees need for healthy growth and productivity
FAR The Floor Area Ratio (FAR) is the total square feet of a building divided by the total square feet of the lot the building is located on.

Flow-Based BMP Flow-based BMPs are conventional treatment control BMPs that are sized to treat the design flow rate.

FPPP Facility Pollution Prevention Plan
HCOC Hydrologic Condition of Concern - Exists when the alteration of a site’s hydrologic regime caused by development would cause significant impacts on downstream channels and aquatic habitats, alone or in conjunction with impacts of other projects.

HMP Hydromodification Management Plan – Plan defining Performance Standards for PDPs to manage increases in runoff discharge rates and durations.

Hydrologic Control
BMP
BMP to mitigate the increases in runoff discharge rates and durations and meet the Performance Standards set forth in the HMP.

HSG Hydrologic Soil Groups – soil classification to indicate the minimum rate of infiltration obtained for bare soil after prolonged wetting. The HSGs are A (very low runoff potential/high infiltration rate), B, C, and D (high runoff potential/very low infiltration rate)
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45 Hydromodification The Regional MS4 Permit identifies that increased volume, velocity, frequency and discharge duration of storm water runoff from developed areas has the potential to greatly accelerate downstream erosion, impair stream habitat in natural drainages, and negatively impact beneficial uses.

JRMP A separate Jurisdictional Runoff Management Plan (JRMP) has been developed by each Copermittee and identifies the local programs and activities that the Copermittee is implementing to meet the Regional MS4 Permit requirements.

LID Low Impact Development (LID) is a site design strategy with a goal of maintaining or replicating the pre-development hydrologic regime through the use of design techniques. LID site design BMPs help preserve and restore the natural hydrologic cycle of the site, allowing for filtration and infiltration which can greatly reduce the volume, peak flow rate, velocity, and pollutant loads of storm water runoff.

LID BMP A type of stormwater BMP that is based upon Low Impact Development concepts. LID BMPs not only provide highly effective treatment of stormwater runoff, but also yield potentially significant reductions in runoff volume – helping to mimic the preproject hydrologic regime, and also require less ongoing maintenance than Treatment Control BMPs. The applicant may refer to Chapter 2.

LID BMP Design
Handbook
The LID BMP Design Handbook was developed by the
Copermittees to provide guidance for the planning, design and maintenance of LID BMPs which may be used to mitigate the water quality impacts of PDPs within the County.

LID Bioretention BMP LID Bioretention BMPs are bioretention areas are vegetated (i.e., landscaped) shallow depressions that provide storage, infiltration, and evapotranspiration, and provide for pollutant removal (e.g., filtration, adsorption, nutrient uptake) by filtering stormwater through the vegetation and soils. In bioretention areas, pore spaces and organic material in the soils help to retain water in the form of soil moisture and to promote the adsorption of pollutants (e.g., dissolved metals and petroleum hydrocarbons) into the soil matrix.

Plants use soil moisture and promote the drying of the soil through transpiration.

The Regional MS4 Permit defines “retain” as to keep or hold in a particular place, condition, or position without discharge to surface waters.

LID Biofiltration BMP BMPs that reduce stormwater pollutant discharges by intercepting rainfall on vegetative canopy, and through incidental infiltration and/or evapotranspiration, and filtration, and other biological and chemical processes. As stormwater passes down through the planting soil, pollutants are filtered, adsorbed, biodegraded, and sequestered by the soil and plants, and collected through an underdrain.

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46 LID Harvest and
Reuse BMP
BMPs used to facilitate capturing Stormwater Runoff for later use without negatively impacting downstream water rights or other Beneficial Uses.

LID Infiltration BMP BMPs to reduce stormwater runoff by capturing and infiltrating the runoff into in-situ soils or amended onsite soils. Typical LID Infiltration BMPs include infiltration basins, infiltration trenches and pervious pavements.

LID Retention BMP BMPs to ensure full onsite retention without runoff of the DCV such as infiltration basins, bioretention, chambers, trenches, permeable pavement and pavers, harvest and reuse.

LID Principles Site design concepts that prevent or minimize the causes (or drivers) of post-construction impacts, and help mimic the predevelopment hydrologic regime.

MEP Maximum Extent Practicable - standard established by the 1987 amendments to the CWA for the reduction of Pollutant discharges from MS4s. Refer to Attachment C of the Regional MS4 Permit for a complete definition of MEP.

MF Multi-family – zoning classification for parcels having 2 or more living residential units.

MS4 Municipal Separate Storm Sewer System (MS4) is a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains): (i) Owned or operated by a State, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, storm water, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or designated and approved management agency under section 208 of the CWA that discharges to waters of the United States; (ii) Designated or used for collecting or conveying storm water; (iii) Which is not a combined sewer; (iv) Which is not part of the Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.26.

New Development
Project
Defined by the Regional MS4 Permit as 'Priority Development Projects' if the project, or a component of the project meets the categories and thresholds described in Section 1.1.1.

NPDES National Pollution Discharge Elimination System - Federal program for issuing, modifying, revoking and reissuing, terminating, monitoring and enforcing permits, and imposing and enforcing pretreatment requirements, under Sections 307, 318, 402, and 405 of the CWA.

NRCS Natural Resources Conservation Service
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47 PDP Priority Development Project - Includes New Development and Redevelopment project categories listed in Provision E.3.b of the Regional MS4 Permit.

Priority Pollutants of
Concern
Pollutants expected to be present on the project site and for which a downstream water body is also listed as Impaired under the CWA Section 303(d) list or by a TMDL.

Project-Specific
WQMP
A plan specifying and documenting permanent LID Principles and Stormwater BMPs to control post-construction Pollutants and stormwater runoff for the life of the PDP, and the plans for operation and maintenance of those BMPs for the life of the project.

Receiving Waters Waters of the United States.

Redevelopment
Project
The creation, addition, and or replacement of impervious surface on an already developed site. Examples include the expansion of a building footprint, road widening, the addition to or replacement of a structure, and creation or addition of impervious surfaces.

Replacement of impervious surfaces includes any activity that is not part of a routine maintenance activity where impervious material(s) are removed, exposing underlying soil during construction. Redevelopment does not include trenching and resurfacing associated with utility work; resurfacing existing roadways; new sidewalk construction, pedestrian ramps, or bike lane on existing roads; and routine replacement of damaged pavement, such as pothole repair.

Project that meets the criteria described in Section 1.

Runoff Fund Runoff Funds have not been established by the Copermittees and are not available to the Applicant.

If established, a Runoff Fund will develop regional mitigation projects where PDPs will be able to buy mitigation credits if it is determined that implementing onsite controls is infeasible.

San Diego Regional
Board
San Diego Regional Water Quality Control Board - The term "Regional Board", as defined in Water Code section 13050(b), is intended to refer to the California Regional Water Quality Control Board for the San Diego Region as specified in Water Code Section 13200. State agency responsible for managing and regulating water quality in the SMR.

SCCWRP Southern California Coastal Water Research Project Site Design BMP Site design BMPs prevent or minimize the causes (or drivers) of post-construction impacts, and help mimic the pre-development hydrologic regime.

SF Parcels with a zoning classification for a single residential unit.

SMC Southern California Stormwater Monitoring Coalition SMR The Santa Margarita Region (SMR) represents the portion of the Santa Margarita Watershed that is included within the County of Riverside.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
48 Source Control BMP Source Control BMPs land use or site planning practices, or structural or nonstructural measures that aim to prevent runoff pollution by reducing the potential for contamination at the source of pollution. Source control BMPs minimize the contact between Pollutants and runoff.

Structural BMP Structures designed to remove pollutants from stormwater runoff and mitigate hydromodification impacts.

SWPPP Storm Water Pollution Prevention Plan
Tentative Tract Map Tentative Tract Maps are required for all subdivision creating five (5) or more parcels, five (5) or more condominiums as defined in Section 783 of the California Civil Code, a community apartment project containing five (5) or more parcels, or for the conversion of a dwelling to a stock cooperative containing five (5) or more dwelling units.

TMDL Total Maximum Daily Load - the maximum amount of a Pollutant that can be discharged into a waterbody from all sources (point and non-point) and still maintain Water Quality Standards. Under CWA Section 303(d), TMDLs must be developed for all
waterbodies that do not meet Water Quality Standards after application of technology-based controls.

USEPA United States Environmental Protection Agency
Volume-Based BMP Volume-Based BMPs applies to BMPs where the primary mode of pollutant removal depends upon the volumetric capacity such as detention, retention, and infiltration systems.

WQMP Water Quality Management Plan
Wet Season The Regional MS4 Permit defines the wet season from October 1 through April 30.

Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
49 Appendix 1: Maps and Site
Plans
Location Map, WQMP Site Plan and Receiving Waters Map
Complete the checklist below to verify all exhibits and components are included in the ProjectSpecific WQMP. Refer Section 4 of the SMR WQMP and Section D of this Template.

Map and Site Plan Checklist
Indicate all Maps and Site Plans are included in your Project-Specific WQMP by checking the boxes below.

Vicinity and Location Map
Existing Site Map (unless exiting conditions are included in WQMP Site Plan) WQMP Site Plan
Parcel Boundary and Project Footprint
Existing and Proposed Topography & Drainage Management Areas (DMAs) Proposed Structural Best Management Practices (BMPs), with cross sections Drainage Paths
Drainage infrastructure, inlets, overflows
Source Control & Site Design BMPs (notes can be used for BMPs that can’t be depicted) Buildings, Roof Lines, Downspouts
Impervious Surfaces
Pervious Surfaces (i.e. Landscaping)
Standardized Labeling
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
50 Appendix 2: Construction
Plans
The latest set of Grading, Drainage Plans, and Street Improvement plans shall be included

VICINITY MAP
CARMAX #1824

MURRIETA, CALIFORNIA

EXHIBIT
N.T.S
STORE NO.: #### 1626 COLE BLVD | SUITE 125 | LAKEWOOD, CO | 80401 NOT FOR CONSTRUCTION Know what's below.

Call before you dig. R
CALL 811 FORTY-EIGHT HOURS

PRIOR TO DIGGING, GRADING OR

EXCAVATING FOR THE MARKING

OF UNDERGROUND MEMBER

UTILITIES

BAR IS ONE INCH ON ORIGINAL DRAWING -

IF NOT ONE INCH ON THIS SHEET ADJUST SCALES

ACCORDINGLY

THE IDEAS & DESIGN INCORPORATED HEREON, AS

AN INSTRUMENT OF PROFESSIONAL SERVICE, IS

THE PROPERTY OF CENTERPOINT ENGINEERING &

IS NOT TO BE USED FOR ANY OTHER PROJECT

WITHOUT WRITTEN AUTHORIZATION OF
CENTERPOINT ENGINEERING.

REV. NO DATE DESCRIPTION BY

REUSE OF DOCUMENT

SCALE VERIFICATION
PROJECT #
DATE

SHEET TITLE
SITE PLAN #
SHEET #
REV. NO DATE DESCRIPTION BY REVISIONS 1824 25560 Madison Ave MURRIETA, CA 1824
2024.08.29

WQMP SITE PLAN
1 OF 1
LEGEND: DRAINAGE NOTES: S S D D D S S D D D E S D D S S S S S S D S MH D MH MH MH MH MH Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
51 Appendix 3: Soils Information
Geotechnical Study, Other Infiltration Testing Data, and/or Other Documentation Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/29/2023

3712130 3712170 3712210 3712250 3712290 3712330 3712370 3712410 3712450 3712130 3712170 3712210 3712250 3712290 3712330 3712370 3712410 3712450 482070 482110 482150 482190 482230 482270 482310
482070 482110 482150 482190 482230 482270 482310
33° 33' 5'' N
117° 11' 35'' W
33° 33' 5'' N
117° 11' 25'' W
33° 32' 54'' N
117° 11' 35'' W
33° 32' 54'' N
117° 11' 25'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 50 100 200 300
Feet
0 20 40 80 120
Meters
Map Scale: 1:1,640 if printed on A portrait (8.5" x 11") sheet.

Soil Map may not be valid at this scale.

MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Rating Polygons
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Lines
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Points
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:15,800.

Warning: Soil Map may not be valid at this scale.

Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale.

Please rely on the bar scale on each map sheet for map
measurements.

Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:

Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required.

This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.

Soil Survey Area: Western Riverside Area, California
Survey Area Data: Version 15, Sep 6, 2022
Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.

Date(s) aerial images were photographed: Mar 14, 2022—Mar 17, 2022
The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident.

Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/29/2023

Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI AtD2 Arlington and Greenfield
fine sandy loams, 8 to
15 percent slopes,
eroded
C 0.0 0.7%
HcC Hanford coarse sandy
loam, 2 to 8 percent
slopes
A 0.6 13.9%
MmC2 Monserate sandy loam,
5 to 8 percent slopes,
eroded
C 2.4 57.6%
MmD2 Monserate sandy loam,
8 to 15 percent
slopes, eroded
C 1.2 27.8%
Totals for Area of Interest 4.2 100.0%
Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/29/2023

Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms.

The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows:

Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission.

Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture.

These soils have a moderate rate of water transmission.

Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission.

Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission.

If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes.

Rating Options
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Hydrologic Soil Group—Western Riverside Area, California Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/29/2023

GEOTECHNICAL EXPLORATION

CARMAX EXPANSION
25560 MADISON AVENUE

MURRIETA, CALIFORNIA
Prepared For CENTERPOINT INTEGRATED SOLUTIONS
1626 COLE BOULEVARD, SUITE 125
LAKEWOOD COLORADO 80401
Prepared By LEIGHTON CONSULTING, INC.
41715 ENTERPRISE CIRCLE N, STE 103
TEMECULA, CA 92590
Project Number 10791.006
April 25, 2023
April 25, 2023
Project No. 10791.006
Centerpoint Integrated Solutions
1626 Cole Boulevard, Suite 125
Lakewood Colorado 80401
Attention: Mr. Scott Caswell
Subject: Geotechnical Exploration
CarMax Expansion
25560 Madison Avenue, Murrieta, California
In accordance with your request, we are pleased to provide this report summarizing our geotechnical findings, conclusions and recommendations regarding the design and construction of the proposed improvements. Based on the results of our evaluation, it is our opinion that the site is suitable for the intended use provided the recommendations included herein are implemented during design and construction phases of development.

If you have any questions regarding this report, please do not hesitate to contact the undersigned. We appreciate this opportunity to be of service on this project.

Respectfully submitted,
LEIGHTON CONSULTING, INC.

Simon I. Saiid, GE
Senior Principal Engineer
Ext 8013, [email protected]
Brent Adam, CEG
Project Geologist
Ext 8923, [email protected]
Distribution: (1) Addressee (PDF copy via email)
Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 i

TABLE OF CONTENTS
Section Page

1.0 INTRODUCTION .................................................................................................... 1

1.1 Purpose and Scope.............................................................................................1

1.2 Site and Project Description................................................................................1

2.0 FIELD EXPLORATION AND LABORATORY TESTING....................................... 3

2.1 Field Exploration..................................................................................................3

2.2 Laboratory Testing ..............................................................................................3

3.0 GEOTECHNICAL AND GEOLOGIC FINDINGS.................................................... 4

3.1 Regional Geology................................................................................................4

3.2 Site Specific Geology ..........................................................................................4

3.3 Groundwater and Surface Water ........................................................................5

3.4 Landslides/Debris Flow and Rockfall..................................................................5

3.5 Regional Faulting and Fault Activity....................................................................5

3.6 Seismicity ............................................................................................................5

3.7 Secondary Seismic Hazards...............................................................................6

3.7.1 Dynamic Settlement (Liquefaction and Dry Settlement)..................................... 6

3.7.2 Seiche and Tsunami............................................................................................7

3.7.3 Expansive Soils....................................................................................................7

3.7.4 Ground Rupture ...................................................................................................7

4.0 CONCLUSIONS AND RECOMMENDATIONS...................................................... 8

4.1 General................................................................................................................8

4.2 Earthwork ............................................................................................................8

4.2.1 Site Preparation and Remedial Grading ............................................................. 8

4.2.2 Structural Fills ......................................................................................................9

4.2.3 Import Soils ..........................................................................................................9

4.2.4 Utility Trenches ....................................................................................................9

4.2.5 Shrinkage...........................................................................................................10

4.2.6 Drainage ............................................................................................................10

4.3 Foundation Design ............................................................................................10

4.3.1 Design Parameters – Spread/Continuous Shallow Footings............................10

4.3.2 Design Parameters – Light Poles......................................................................11

4.4 Retaining Walls ................................................................................................. 11

4.5 Sulfate Attack ....................................................................................................12

4.6 Preliminary Pavement Design...........................................................................12

5.0 GEOTECHNICAL CONSTRUCTION SERVICES ................................................ 15

6.0 LIMITATIONS....................................................................................................... 16 REFERENCES.............................................................................................................. 17 Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 ii
Accompanying Tables, Figures, Plates and Appendices
Tables
Table 1. 2022 CBC Seismic Coefficients per USGS General Procedure ....................... 6 Table 2. Retaining Wall Design Earth Pressures (Static, Drained)............................... 12 Table 3. Asphalt Pavement Sections............................................................................ 13 Figures
Figure 1 – Site Location Map End of Text
Figure 2 – Regional Geology Map End of Text
Figure 3 – Fault Zone Map End of Text
Figure 4 – Boring Location Map End of Text
Appendices
Appendix A – Logs of Exploratory Borings
Appendix B – Results of Geotechnical Laboratory Testing Appendix C – Earthwork and Grading Specifications
Appendix D – GBA - Important Information About This Geotechnical-Engineering Report Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 1 1.0 INTRODUCTION

1.1 Purpose and Scope
This geotechnical exploration is for the proposed expansion of the existing CarMax facility located at 25560 Madison Avenue, in the City of Murrieta, California (see Figure 1). Our scope of services for this exploration included the following:
 Review of available site-specific geologic information, including our previous report prepared for the overall CarMax site (Leighton, 2014).
 A site reconnaissance and excavation, logging, and sampling of seven (7) exploratory borings. Approximate locations of these 7 borings and previous 4 borings are depicted on Figure 4. The logs of exploratory borings are presented in Appendix A.  Geotechnical laboratory testing of selected soil samples collected during this evaluation. Test results are presented in Appendix B.
 Geotechnical engineering analyses performed or as directed by a California registered Geotechnical Engineer (GE) and reviewed by a California Certified Engineering Geologist (CEG).
 Preparation of this report, which presents our geotechnical conclusions and recommendations regarding the proposed structures.

This report is not intended to be used as an environmental assessment (Phase I or other), or foundation plan review.

1.2 Site and Project Description
As depicted in Figure 1, the site of the proposed expansion is generally located between Madison Avenue and the existing CarMax automotive dealership, just south of Wal-Mart, in the City of Murrieta, California. The site consists of three (3) individual parcels designated as Assessor Parcel Numbers (APNs): 910-490-013, -001, and -002. APN 910-490-013 (Site 1) is approximately 0.92 acre and constitutes the northern site. APNs 910-490-001, and -002 are adjoining parcels and constitute the southern site (site 2), which is approximately 3.58 acres in size. These two sites are separated by Parcel 910- 490-015 (Not a Part of this study).

The above three parcels are currently vacant land with the exception of the two detention basins located in the northern and southern parcels. The overall site topography gently slopes in a southerly direction toward Madison Avenue. Site vegetation generally consists of annual weeds and grasses.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 2 We understand that the proposed site improvements will consist of expanding the existing staging lot area into the middle and northern parcels. The carrier parking area will be extended into the southern parcel. This expansion will generally involve minor and fill grading (±5 feet) to achieve finish grades for the new pavement associated with the proposed driveways and parking areas.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 3 2.0 FIELD EXPLORATION AND LABORATORY TESTING

2.1 Field Exploration
Our field exploration for this study consisted of the excavation of an additional seven (7) new hollow stem auger borings in the planned new parking areas. During exploration, disturbed/bulk and relatively undisturbed samples were collected for further laboratory testing and evaluation. Approximate locations of these borings along with previous borings are depicted on the Boring Location Plan (see Figure 4). Sampling and logging were conducted by a geologist from our firm. After logging and sampling, the excavations were loosely backfilled with spoils generated during excavation. The exploration logs from this and previous explorations are provided in Appendix A.

2.2 Laboratory Testing
Laboratory tests were performed on representative bulk samples to provide a basis for development of earthwork control and foundation design. The laboratory testing program included maximum density and moisture content relationship, expansion index, collapse potential, corrosion suite, R-value and sieve analysis. The results of our laboratory testing from this and previous explorations are presented in Appendix B.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 4 3.0 GEOTECHNICAL AND GEOLOGIC FINDINGS

3.1 Regional Geology
The site is located within a prominent natural geomorphic province in southwestern California known as the Peninsular Ranges. This province is characterized by steep, elongated ranges and valleys that trend northwestward. More specifically, the site is located within the southwestern portion of the relatively stable Perris Block, adjacent to the Elsinore Trough (Kennedy, 1977).

The Perris Block, approximately 20 miles by 50 miles in extent, is bounded by the San Jacinto Fault Zone to the northwest, the Elsinore Fault Zone to the southwest, the Cucamonga Fault Zone to the northwest, and the Temecula Basin to the southeast. The Perris Block has had a complex tectonic history, apparently undergoing relative vertical land-movements of several thousand feet in response to movement on the Elsinore and San Jacinto Fault Zones. Thin sedimentary and volcanic materials locally mantle crystalline bedrock. Alluvial fan deposits fill the lower valley areas, as mapped regionally on Figure 2, Regional Geology Map.

3.2 Site Specific Geology

3.2.1 Earth Materials
Our field exploration, observations, and review of the pertinent literature indicate that the site is underlain by a Pleistocene-age coarse-grained formation (locally known as Pauba Formation). Formational materials were overlain on-site by artificial fill, likely associated with construction of the existing CarMax facility. These units are further discussed in the following sections and a more detailed description of each unit is provided on the logs of borings in Appendix A.
 Artificial Fill: Artificial fill soils were encountered in our exploratory borings to depths ranging from 8 to 10 feet BGS and generally consisted of medium dense to dense clayey sand (SC). This fill is likely derived from onsite sources and assumed to have been placed during grading of the existing CarMax facility.

Documentation of the placement and compaction of this artificial fill was not available at the time of this report preparation. However, based on the results of our field and laboratory testing, these materials possess adequate relative density and very low expansion potential (EI<21).
 Pauba Formation: The Pauba Formation bedrock materials were encountered in all of our borings below the artificial fill. These materials generally consist of medium-dense to very dense, silty sands (SM) and clayey sands (SC). Based on the results of our laboratory testing, these materials appear to have a very slight collapse potential (<1%) and generally possess adequate relative density.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 5 3.3 Groundwater and Surface Water
Groundwater was not encountered during this exploration to the total depth of 21.5 feet BGS, however groundwater was encountered during the previous exploration at a depth of approximately 48.3 feet BGS in boring LB-13 (EL.~1045). This boring was located within a local drainage swale in the central portion of the overall CarMax site. The Department of Water Resource data for two local wells (Well 07S03W21K002S & 07S03W15N002S) indicate a groundwater elevation to be approximately elevation 1035, or on the order of 50 to 80 feet below site ground elevations. However, it should be noted that local perched water conditions may occur in the future, and may fluctuate seasonally, depending on rainfall conditions. Seasonal surface water should be expected within the onsite drainage culvert/channel.

3.4 Landslides/Debris Flow and Rockfall
No evidence of on-site landslides/debris flow or rock fall was observed during our field investigation. Due to lack of exposed rock and relatively low topographic relief of surrounding properties, the potential for rock fall due to either erosion or seismic ground shaking is considered negligible.

3.5 Regional Faulting and Fault Activity
The subject site, like the rest of Southern California, is located within a seismically active region as a result of being located near the active margin between the North American and Pacific tectonic plates. The principal source of seismic activity is movement along the northwest-trending regional fault systems such as the San Andreas, San Jacinto, and Elsinore Fault Zones. Based on published geologic hazard maps, the proposed expansion is not located within a currently designated Alquist-Priolo (AP) Earthquake Fault Zone. However, a County of Riverside Fault Zone is located along the northwest corner of Site 1, which should not impact the proposed parking expansion.

3.6 Seismicity
As is common for virtually all of Southern California, strong ground shaking can be expected at the site during moderate to severe earthquakes in this general region.

Intensity of ground shaking at a given location depends primarily upon earthquake magnitude, site distance from the source, and site response (soil type) characteristics.

The seismic coefficients were calculated utilizing an interactive program on current United States Geological Survey (USGS) website using ASCE 7-16 procedures, as well as USGS Unified Hazard Maps. Based on our exploration and review, the site will be Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 6 underlain by relatively alluvial materials. As such, the site is classified as a Class D site, and the site-specific seismic coefficients are as listed in the following table:

Table 1. 2022 CBC Seismic Coefficients per USGS General Procedure Site Seismic Coefficients / Coordinates Value
Latitude 33.5525
Longitude -117.1897
Mapped Spectra (OSHPD)
Spectral Response – Class D (short), SS 1.61
Spectral Response – Class D (1 sec), S1 0.60
Site Modified Peak Ground Acceleration, PGAM 0.79
Max. Considered Earthquake Spectral Response Acceleration (short), SMS 1.61 Max. Considered Earthquake Spectral Response Acceleration – (1 sec), SM1 1.03* 5% Damped Design Spectral Response Acceleration (short), SDS 1.07 5% Damped Design Spectral Response Acceleration (1 sec), SD1 0.69* Peak Ground Acceleration, PGA 0.72
g = Gravity acceleration
*Per Exception 2 in Section 11.4.8 of ASCE 7-16, seismic response coefficient CS to be determined by Eq. 12.8-2 for values of T < 1.5Ts and taken as equal to 1.5 times the value computed in accordance with either Eq. 12.8-3 for TL > T > 1.5Ts or Eq. 12.8-4 for T > TL g = Gravity acceleration
The project structural engineer should confirm if the above exception applies to the proposed improvements, else a site–specific ground motion analysis may be required.

3.7 Secondary Seismic Hazards
Ground shaking can induce “secondary” seismic hazards such as liquefaction, dynamic densification, lateral spreading, flooding, seiche/tsunami, collapsible soils, and ground rupture, as discussed in the following subsections:

3.7.1 Dynamic Settlement (Liquefaction and Dry Settlement) A portion of the site contains a Riverside County Liquefaction Hazard zone primarily in a previous drainage alignment. Liquefaction is the loss of soil strength or stiffness due to a buildup of pore-water pressure during severe ground shaking. Liquefaction is associated primarily with loose (low density), saturated, fine- to medium-grained, cohesionless soils. Due to proposed remedial grading of alluvium in natural drainages, the lack of shallow groundwater and relatively dense nature of underlying materials (dense Pauba formation), the potential for liquefaction/dynamic-induced settlement is considered very low or less than 0.5 inch. If occurred, this settlement is expected to be generally global and over a large area. As such, the differential seismic settlement is expected to be less than 0.25-inch in a 30-foot horizontal distance within this site.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 7 3.7.2 Seiche and Tsunami
Due to the site location and lack of nearby open bodies of water, the possibility of the affects due to seiches or tsunami is considered nil.

3.7.3 Expansive Soils
Based on the sandy nature of the encountered soils onsite, we anticipate the alluvial soils generally possess a very low expansion potential (EI<21).

3.7.4 Ground Rupture
Since this site is not located within a mapped Fault Zone and there are no known faults within or trending into the property, the possibility of ground surface-faultrupture is very low at this site.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 8 4.0 CONCLUSIONS AND RECOMMENDATIONS

4.1 General
Based on the results of this exploration, it is our opinion that the site is suitable for the proposed development from a geotechnical viewpoint. Grading of the site should be in accordance with our recommendations included in this report and future recommendations and evaluations made during construction by the geotechnical consultant.

4.2 Earthwork
Earthwork should be performed in accordance with the General Earthwork and Grading Specifications in Appendix C as well as the following recommendations. The recommendations contained in Appendix C are general grading specifications provided for typical grading projects and some of the recommendations may not be strictly applicable to this project. The specific recommendations contained in the text of this report supersede the general recommendations in Appendix C.

The contract between the developer and earthwork contractor should be worded such that it is the responsibility of the contractor to place fill properly in accordance with the recommendations of this report, the specifications in Appendix C, applicable Grading Ordinances, notwithstanding the testing and observation of the geotechnical consultant during construction.

4.2.1 Site Preparation and Remedial Grading
Prior to grading, the proposed structural improvement areas (i.e. all-structural fill areas, pavement areas, etc.) should be cleared of stock piled soils, debris, vegetation, surface and subsurface pipelines and obstructions. Heavy vegetation, roots and debris should be disposed of offsite. Voids created by removal of buried/unsuitable materials should be backfilled with properly compacted soil in general accordance with the recommendations of this report.  Structural Improvements/Settlement-Sensitive Structures (i.e. Retaining walls, etc.): Whether in a fill or cut condition, the depth of removal should extend a minimum of 3 feet below existing grades or 2 feet below footings, whichever is deeper. Deeper removal may be required in localized areas based on prevailing subgrade conditions during grading. Subgrade soils should consist of compacted very low expansive soils (EI<21). Overexcavation should encompass the entire foundation or extend laterally beyond the foundation limits a horizontal distance equal to the depth of overexcavation.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 9  Vehicular Pavement/Hardscape: The upper 2 feet of existing soils or 12 inches below bottom of pavement, whichever is deeper, should be removed and re-compacted.

After completion of the recommended removal and prior to placing additional fill, the approved bottom of removal should be scarified a minimum of 8 inches, moisture conditioned and compacted to a minimum 90 percent of the maximum dry density in accordance with ASTM D1557.

4.2.2 Structural Fills
The onsite soils are generally suitable for re-use as compacted fill, provided they are free of debris and organic matter. If encountered, expansive clayey/silty soil (EI>51) should be removed or placed at a depth greater than 3 feet below finished grades.

In addition, these soils may require some dry back to near optimum moisture content prior to placement as compacted fill.

Placement and compaction of fill should be performed in accordance with the City of Murrieta Grading Ordinance under the observation and testing of the geotechnical consultant. The optimum lift thickness to produce a uniformly compacted fill will depend on the type and size of compaction equipment used. In general, fill should be placed in uniform lifts not exceeding 8 inches in thickness.

4.2.3 Import Soils
Import soils and/or borrow sites, if needed, should be evaluated by us prior to import.

Import soils should be uncontaminated, granular in nature, free of organic material (loss on ignition less-than 2 percent), have very low expansion potential (E<21) and have a low corrosion impact to the proposed improvements.

4.2.4 Utility Trenches
Utility trenches should be backfilled with compacted fill in accordance with the Standard Specifications for Public Works Construction, (“Greenbook”), 2021 Edition.

Fill material above the pipe zone should be placed in lifts not exceeding 8 inches in uncompacted thickness and should be compacted to at least 90 percent relative compaction (ASTM D 1557) by mechanical means only. Site soils may generally be suitable as trench backfill provided these soils are screened of rocks over 1½ inches in diameter and organic matter. If imported sand is used as backfill, the upper 3 feet in building and pavement areas should be compacted to 95 percent. The upper 6 inches of backfill in all pavement areas should be compacted to at least 95 percent relative compaction.

Excavation of utility trenches should be performed in accordance with the project plans, specifications, and the California Construction Safety Orders (latest Edition).

The contractor should be responsible for providing a "competent person" as defined in Article 6 of the California Construction Safety Orders. Contractors should be advised that sandy soils (such as fills generated from the onsite alluvium) could Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 10 make excavations particularly unsafe if all safety precautions are not properly implemented. In addition, excavations at or near the toe of slopes and/or parallel to slopes may be highly unstable due to the increased driving force and load on the trench wall. Spoil piles from the excavation(s) and construction equipment should be kept away from the sides of the trenches. Leighton Consulting, Inc. does not consult in the area of safety engineering.

4.2.5 Shrinkage
The volume change of excavated onsite soils upon recompaction is expected to vary with materials, density, insitu moisture content, and location and compaction effort.

The in-place and compacted densities of soil materials vary, and accurate overall determination of shrinkage and bulking cannot be made. Therefore, we recommend site grading include, if possible, a balance area or ability to adjust grades slightly to accommodate some variation. Based on our test results, we expect recompaction shrinkage (when recompacted to an average 92 percent of ASTM D1557) to vary between 10% and 15%, where the shrinkage decreases with depth.

4.2.6 Drainage
All drainage should be directed away from structures and pavements by means of approved permanent/temporary drainage devices. Adequate storm drainage of any proposed pad should be provided to avoid wetting of foundation soils. Irrigation adjacent to buildings should be avoided when possible. As an option, sealed-bottom planter boxes and/or drought resistant vegetation should be used within 5-feet of buildings.

4.3 Foundation Design

4.3.1 Design Parameters – Spread/Continuous Shallow Footings Footings should be embedded at least 12-inches below lowest adjacent grade for the proposed structure. Footing embedment should be measured from lowest adjacent finished grade, considered as the top of interior slabs-on-grade or the finished exterior grade, excluding landscape topsoil, whichever is lower. Footings located adjacent to utility trenches or vaults should be embedded below an imaginary 1:1 (horizontal:vertical) plane projected upward and outward from the bottom edge of the trench or vault, up towards the footing.  Bearing Capacity: For footings on newly placed, properly compacted fill soil, an allowable vertical bearing capacity of 2,000 pounds-per-square-foot (psf) should be used. These footings should have a minimum base width of 18 inches for continuous wall footings and a minimum bearing area of 3 square feet (1.75-ft by 1.75-ft) for pad foundations. Additionally, these bearing values may be increased by one-third when considering short-term seismic or wind loads. A modulus of subgrade reaction, K of 150 PCI may be used to onsite soil compacted to minimum 90% relative compaction.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 11  Lateral loads: Lateral loads may be resisted by friction between the footings and the supporting subgrade. A maximum allowable frictional resistance of

0.35 may be used for design. In addition, lateral resistance may be provided by passive pressures acting against foundations poured neat against properly compacted granular fill. We recommend that an allowable passive pressure based on an equivalent fluid pressure of 350 pounds-per-cubic-foot (pcf) be used in design. These friction and passive values have already been reduced by a factor-of-safety of 1.5.

4.3.2 Design Parameters – Light Poles
For light poles or any other similar structure founded on 24- or 30-inch drilled piers extending to a minimum of 5 feet below proposed finish grade, the following geotechnical parameters should be considered for design:
 An allowable end bearing pressure of 2,500 psf may be used if the pier is embedded a minimum of 5 feet into compacted fill or competent Pauba formation bedrock. An increase of 250 psf may be applied for every foot of depth thereafter, to a maximum pressure of 4,000 psf. A one-third increase in allowable pressure may be used for short duration loads as wind or seismic.  Uplift resistance should be limited to the weight of the pier plus 800 psf of skin friction for the portion of pier below 3 feet. Resistance to lateral loads will be provided by the passive earth pressure against the sides of the pier. The passive earth pressure may be computed as an equivalent fluid having a density of 300 psf per foot of depth, to a maximum earth pressure of 3,500 psf.

4.4 Retaining Walls
Retaining wall earth pressures are a function of the amount of wall yielding horizontally under load. If the wall can yield enough to mobilize full shear strength of backfill soils, then the wall can be designed for "active" pressure. If the wall cannot yield under the applied load, the shear strength of the soil cannot be mobilized, and the earth pressure will be higher. Such walls should be designed for "at rest" conditions. If a structure moves toward the soils, the resulting resistance developed by the soil is the "passive" resistance.

Retaining walls backfilled with non-expansive soils can be designed using the following equivalent fluid pressures:

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 12 Table 2. Retaining Wall Design Earth Pressures (Static, Drained) Loading
Conditions
Equivalent Fluid Density (pcf)
Level Backfill 2:1 Backfill
Active 33 52
At-Rest 55 75
Passive* 300 150 (2:1, sloping down)
* This assumes level condition in front of the wall will remain for the duration of the project, not to exceed 3,500 psf at depth.

Unrestrained (yielding) cantilever walls should be designed for the active equivalent-fluid weight value provided above for very low expansive soils that are free draining. In the design of walls restrained from movement at the top (non-yielding) such as basement or elevator pit/utility vaults, the at-rest equivalent fluid weight value should be used. Total depth of retained earth for design of cantilever walls should be measured as the vertical distance below the ground surface measured at the wall face for stem design or measured at the heel of the footing for overturning and sliding calculations. Should a sloping backfill other than a 2:1 (horizontal: vertical) be constructed above the wall (or a backfill is loaded by an adjacent surcharge load), the equivalent fluid weight values provided above should be re-evaluated on an individual case basis by us. Non-standard wall designs should also be reviewed by us prior to construction to check that the proper soil parameters have been incorporated into the wall design.

All retaining walls should be provided with appropriate drainage. The outlet pipe should be sloped to drain to a suitable outlet. Wall backfill should be non-expansive (EI ≤ 21) sands compacted by mechanical methods to a minimum of 90 percent relative compaction (ASTM D 1557). Clayey site soils should not be used as wall backfill. Walls should not be backfilled until wall concrete attains the 28-day compressive strength and/or as determined by the Structural Engineer that the wall is structurally capable of supporting backfill. Lightweight compaction equipment should be used, unless otherwise approved by the Structural Engineer.

4.5 Sulfate Attack
Based on laboratory testing, the onsite soils are expected to possess negligible sulfate content (<1,000 ppm). Type II cement or equivalent may be used. Further testing should be performed at the completion of site grading to confirm such conditions.

4.6 Preliminary Pavement Design
The preliminary pavement design provided below is based on the locally accepted Caltrans Highway Design Manual and an average R-value of 17 based on our laboratory Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 13 testing. For planning and estimating purposes, the pavement sections are calculated based on Traffic Indexes (TI) indicated in Table below and provided by CarMax.

Table 3. Asphalt Pavement Sections
General Traffic
Condition
Traffic
Index (TI)
Hot Mix Asphalt
HMA (inches)
Aggregate Base*
AB (inches)
Automobile Parking
Stalls 4.5 4.0 4.0
Light Duty Automobile
Drive Lane/Parking 5.5 4.0 8.0
Heavy Duty Drive &
Truck Access 6.5 4.0 11.0
Location of applicable Traffic Index (TI) should be designated by the project civil engineer. Actual R-value of the subgrade soils should be verified after completion of site grading to finalize the pavement design. Per CarMax requirement, the HMA layer should be a minimum of 4 inches in thickness and placed in two layers.

Based on local practices, the surface course should be a minimum of 1.5 inches thick and consist of Type C2 PG70-10 per Section 203-6 of the “Standard Specifications for Public Works Construction” (Greenbook), current edition. The base course should be a minimum of 2.5 inches thick and consist of Type B PG70-

10. Other HMA grades or mixes may be specified by Client and/or Architect pending approval by City and conforming to applicable Greenbook requirements.

Where applicable, we recommend that a minimum of 6 inches of PCC pavement be used, in high impact load areas or if to be subjected to truck traffic. The PCC pavement should be placed on a minimum 6-inch aggregate base. The PCC pavement may be placed directly on a compacted subgrade with an R-Value of 40 or higher. The PCC pavement should have a minimum of 28-day flexural strength of 550 psi. Design and placement of concrete materials should be follow applicable ACI and City standards.

The upper 8 inches of pavement area subgrade soils should be moistureconditioned to near optimum moisture content, compacted to at least 95 percent relative compaction (ASTM D1557) and kept in this condition until the pavement section is constructed. Minimum relative compaction requirements for aggregate base should be 95 percent of the maximum laboratory density as determined by ASTM D1557. If applicable, aggregate base should conform to Greenbook or Caltrans Class 2 aggregate base.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 14 If pavement areas are adjacent to heavily watered landscape areas, some deterioration of the subgrade load bearing capacity may result. Moisture control measures such as deepened curbs or other moisture barrier materials may be used to prevent the subgrade soils from becoming saturated. The use of concrete cutoff or edge barriers should be considered when pavement is planned adjacent to either open (unfinished) or irrigated landscaped areas.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 15 5.0 GEOTECHNICAL CONSTRUCTION SERVICES
Geotechnical review is of paramount importance in engineering practice. Poor performances of many foundation and earthwork projects have been attributed to inadequate construction review. We recommend that Leighton Consulting, Inc. be provided the opportunity to review the grading plan and foundation plan(s) prior to bid.

Reasonably-continuous construction observation and review during site grading and foundation installation allows for evaluation of the actual soil conditions and the ability to provide appropriate revisions where required during construction. Geotechnical conclusions and preliminary recommendations should be reviewed and verified by Leighton Consulting, Inc. during construction, and revised accordingly if geotechnical conditions encountered vary from our findings and interpretations. Geotechnical observation and testing should be provided:
 After completion of site demolition and clearing,
 During over-excavation of compressible soil,
 During compaction of all fill materials,
 After excavation of all footings and prior to placement of concrete,  During utility trench backfilling and compaction, and  When any unusual conditions are encountered.

Additional geotechnical exploration and analysis may be required based on final development plans, for reasons such as significant changes in proposed structure locations/footprints. We should review grading (civil) and foundation (structural) plans, and comment further on geotechnical aspects of this project.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 16 6.0 LIMITATIONS
This report was based in part on data obtained from a limited number of observations, site visits, soil excavations, samples, and tests. Such information is, by necessity, incomplete. The nature of many sites is such that differing soil or geologic conditions can be present within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur over time. Therefore, our findings, conclusions and recommendations presented in this report are based on the assumption that we (Leighton Consulting, Inc.) will provide geotechnical observation and testing during construction as the Geotechnical Engineer of Record for this project. Please refer to Appendix D, GBA’s Important Information About This Geotechnical-Engineering Report, prepared by the Geoprofessional Business Association (GBA) presenting additional information and limitations regarding geotechnical engineering studies and reports.

This report was prepared for the sole use of Client and their design team, for application to design of the proposed maintenance building, in accordance with generally accepted geotechnical engineering practices at this time in California. Any unauthorized use of or reliance on this report constitutes an agreement to defend and indemnify Leighton Consulting, Inc. from and against any liability, which may arise as a result of such use or reliance, regardless of any fault, negligence, or strict liability of Leighton Consulting, Inc.

Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023 17 REFERENCES
Army Corps of Engineers, Evaluation of Settlement for Dynamic and Transient Loads, Technical Engineering and Design Guides as Adapted from the US Army Corps of Engineers, No. 9, American Society of Civil Engineers Press.

American Society of Civil Engineers, 2016, Minimum Design Loads for Buildings and Other Structures, ASCE/SEI 7-16 Publication.

Bryant, W. A. and Hart, E.W., 2007, Fault-Rupture Hazard Zones in California, AlquistPriolo Earthquake Fault Zoning with Index to Earthquake Zones Maps: Department of Conservation, Division of Mines and Geology, Special Publication 42. Interim Revision 2007.

California Building Code (CBC), 2022, California Code of Regulations Title 24, Part 2, Volume 2 of 2.

California Department of Water Resources, 2023, Water Data Library, viewed April 18, 2023, www.water.ca.gov/waterdatalibrary.

California Geologic Survey (CGS), 2003. The Revised 2002 California Probabilistic Seismic Hazard Maps, June 2003. By Tianquing Cao, William A. Bryant, Badie Rowshandel, David Branum and Christopher J. Wills.

California Geological Survey, (CGS), 2006, Geologic Map of the San Bernardino and Santa Ana 30’ X 60’ Quadrangle, Southern California, Version 1.0, Compiled by Douglas M. Morton and Fred K. Miller, Open File Report 06-1217.

Morton, D.M., and Miller, F.K., Geologic Map of the San Bernardino and Santa Ana 30’x 60’ Quadrangles, California, USGS Open File Report 2006-1217, Dated 2006.

OSHPD, 2023, Seismic Design Maps, an interactive computer program on OSHPD website to calculate Seismic Response and Design Parameters based on ASCE 7-16 seismic procedures, https://seismicmaps.org/
Public Works Standard, Inc., 2021, Greenbook, Standard Specifications for Public Works Construction: 2021 Edition, BNI Building News, Anaheim, California.

Riverside County, 2023, County of Riverside General Plan, Riverside County Integrated Project Website.
³ 0 2,000 4,000
Feet
Scale:1 " = 2,000 '
Project: 10791.006 Eng/Geol: BAA
Map Saved as V:\Drafting\10791\006\Maps\10791-006_F01_SLM_2023-04-21.mxd on 4/21/2023 3:22:28 PM Author: KVM (mmurphy) Date: April 2023

SITE LOCATION MAP
Carmax Expansion
25560 Madison Avenue
Murrieta, California
FIGURE 1
Reference: © 2023 Microsoft Corporation ©
2023 Maxar ©CNES (2023) Distribution Airbus
Approximate
Site Locations
!"a$
%&h(
Qya
Qya
Qya
Qyf
QTws
QTws
Qps
Qps
Qps
Qps
Qps
Qyv
Qyv
Qpf
Qpf
QTws
Qyls
Qyls
Qya
Qya
Qyv
Kgb
QTws
Trmu
Qps
Qya
Qyf
Qpf
California Oaks Rd
Alta Murrieta Dr
Jefferson Ave
Murrieta Hot Springs Rd
Kalmia St
Jackson Ave
Ivy St
Whitewood Rd
Los Alamos Rd
Washington Ave

REGIONAL GEOLOGY MAP
Approximate
Site Locations
³ 0 2,000 4,000
Feet
Legend
Qyls - Young landslide
Qyf - Young alluvial-fan
!
! !
!! !
! !
!
!
!
! !! ! !
! ! ! !
! !
Qya - Young axial-channel
Qyv - Young alluvial-valley
Kgb - Gabbro, undifferentiated
QTws - Sandstone and conglomerate
of Wildomar area
Qpf - Pauba Formation
Qps - Pauba Formation
Reference: USGS, 2006 Geologic map of the San
Bermardino and Santa Ana 30'x60 quadrangle,
California Version 1,0 Open File Report 2006-1217.

Scale:1 " = 2,000 '
Project: 10791.006 Eng/Geol: BAA
Map Saved as V:\Drafting\10791\006\Maps\10791-006_F02_RGM_2023-04-21.mxd on 4/21/2023 3:39:21 PM Author: Leighton Geomatics (mmurphy) Date: April 2023
FIGURE 2
Carmax Expansion
25560 Madison Avenue
Murrieta, California
Scale:1 " = 2,000 feet
Project: 10791.006 Eng/Geol: BAA
Map Saved as V:\Drafting\10791\006\Maps\10791-006_F03_FHM_2023-04-21.mxd on 4/21/2023 4:04:00 PM Author: (mmurphy)
Date: April 2023

FAULT HAZARD MAP
Approximate
Site Locations
FIGURE 3
Legend
Faults
Alquist-Priolo
Riverside County
Fault Zones
Alquist-Priolo
Riverside County
Reference: Riverside County Mapping Portal,
9/9/2019.© 2023 Microsoft Corporation
Carmax Expansion
25560 Madison Avenue
Murrieta, California
³ 0 2,000 4,000
Feet
³
080160
Feet
MapSavedasV:\Drafting\10791\006\Maps\10791-006_F02_BLM_2023-04-21.mxdon4/21/20233:14:46PM

BORINGLOCATIONMAP
CarmaxExpansion
25560MadisonAvenue
Murrieta,California
Scale:

BaseMap:As-BuiltSitePlanbyCarMax
BingMaps,2023
1"=80'
Project:10791.006
Eng/Geol:BAA
Author:LeightonGeomatics(mmurphy)
Date:April2023
FIGURE4
Legend
&<
ApproximateLocationofBoring
(ThisStudy)
&(
ApproximateLocationofBoring
(Leighton,2014)
ApproximateSiteBoundary
LB-10
LB-40
Geotechnical Exploration 10791.006
25560 Madison Avenue, Murrieta, California April 25, 2023

APPENDIX A

LOGS OF EXPLORATORY BORINGS
Encountered earth materials were logged and sampled in the field by our representative and described in accordance with the Unified Soil Classification System (ASTM D 2488).

Representative soil samples were transported to our in-house Temecula laboratory for geotechnical testing. After logging and sampling, our borings were backfilled with spoils generated during drilling.

The attached subsurface exploration logs and related information depict subsurface conditions only at the locations indicated and at the particular date designated on these logs. Subsurface conditions at other locations may differ from conditions occurring at these logged locations. Passage of time may result in altered subsurface conditions due to environmental changes. In addition, any stratification lines on these logs represent an approximate boundary between sampling intervals and soil types; and transitions may be gradual.
10 18
29 15
21 27
10 15
16 10
18 20
12 13
16 119
119
SC
SC
R1
R2
S3
R4
S5
7 9
Artificial Fill (Afu)
CLAYEY SAND, dense, yellowish brown, moist, fine to coarse sand
Pauba Formation (Qps)
CLAYEY SAND, dense, light reddish brown to olive, moist, fine to medium sand
olive to yellowish brown
yellowish brown
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-10
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
11 19
20 14
19 20
8 5
12 15
18 20
12 14
15 120
115
SC
SC
B1
R2
R3
S4
R5
S6
11 7
Artificial Fill (Afu)
CLAYEY SAND, loose, brown, moist, fine to coarse sand
dense, brown to reddish yellow
Pauba Formation (Qps)
CLAYEY SAND, medium dense, yellowish red to olive, fine to medium sand
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23
MD, RV
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-2
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
10 11
4 10
18 21
10 11
12 12
14 16
14 15
18 109
117
113
SC
SC
B1
R2
R3
S4
R5
S6
11 9
10 Artificial Fill (Afu)
CLAYEY SAND, loose, brown to reddish brown, slightly moist Pauba Formation (Qps)
CLAYEY SAND, dense, yellowish red to light brown, moist, fine to coarse sand
medium dense, olive, banded iron oxide staining
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23
CO, EI
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-4
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
15 24
34 5
11 25
10 14
16 10
14 28
10 14
16 115
107
SC
SC
R1
R2
S3
R4
S5
7 8
Artificial Fill (Afu)
CLAYEY SAND, very dense, brown, moist, fine to coarse sand Pauba Formation (Qps)
CLAYEY SAND, loose to medium dense, olive brown to brown, moist, fine to medium sand
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-5
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
15 18
27 16
19 27
10 12
21 18
21 27
13 16
17 124
123
SC
SM
SC
B1
R2
R3
S4
R5
S6
10 8
Artificial Fill (Afu)
CLAYEY SAND, very dense, yellowish brown to brown, moist, fine to coarse sand, trace gravel
SA: 2% Gravel, 33% Fines
Pauba Formation (Qps)
SILTY SAND, dense, yellowish brown, moist, fine to coarse sand
CLAYEY SAND, dense, yellowish brown, moist, fine to coarse sand
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23
MD, SA
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-6
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
9 12
14 13
27 24
14 15
17 14
16 17
12 15
19 107
125
SC
SC
B1
R2
R3
S4
R5
S6
14 6
Artificial Fill (Afu)
CLAYEY SAND, medium dense, brown, moist, fine to coarse sand
dense, yellowish red
Pauba Formation (Qps)
CLAYEY SAND, dense, yellowish brown, moist, fine to coarse sand
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23

AL, CR,
EI
CO
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-7
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
20 25
29 16
24 25
15 15
17 15
24 29
10 15
20 131
120
107
SC
SM
SC
R1
R2
S3
R4
S5
9 6
11 Artificial Fill (Afu), dense, brown, moist, fine to coarse sand Pauba Formation (Qps)
SILTY SAND, dense, yellowish brown, moist, fine to medium sand
CLAYEY SAND, dense, yellowish brown to olive, moist, fine to coarse sand
Total Depth = 21.5'
Groundwater not encountered during drilling
Backfilled with on-site soils on 3/27/23
Hole Diameter Moisture
Ground Elevation
Depth Blows Elevation Per 6 Inches

1095'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
ARB
Hollow Stem Auger - 140lb - Autohammer - 8" Drop Soil Class. 3-27-23

SOIL DESCRIPTION
Sampled By
Drilling Co.Drilling Co.

Project
Project No.

See Geotechnical Mp
CarMax
10791.006
Drilling Method
8" Sample No. Feet Attitudes
SAMPLE TYPES:

Veteran Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-8
Logged By
Date Drilled
ARB Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC
1095
1090
1085
1080
1075
1070
1065
0 5
10 15
20 25
30 SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE

STRENGTH
SM
R-1
R-2
R-3
Pauba Formation (Qps); SILTY SAND with GRAVEL, grayish
brown, dry to moist, fine to coarse grained sand with fine gravel SILTY SAND, pale brown, moist, fine to medium grained sand SILTY SAND, dense, olive brown, moist, fine to medium grained sand
SILTY SAND, olive brown, moist, fine to medium grained sand SILTY SAND, dense, dark grayish brown, moist, fine grained sand SILTY SAND, medium dense, dark grayish brown, moist, fine to medium grained sand Total Depth = 16.5' bgs, no groundwater encountered, backfilled with cuttings on 08/13/14 15 42
50/4"
23 50
8 19
26 ~1099'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
JTD
Hollow Stem Auger - 140lb - Autohammer - 30" Drop Soil Class. 8-13-14

SOIL DESCRIPTION
Sampled By
Drilling Co.

Project
Project No.

See Plate 1
Proposed CarMax, Murrieta
10791.002
Drilling Method
8" Sample No. Feet
Hole Diameter Moisture
Ground Elevation
Depth
0 5
10 15
20 25
30 Blows Elevation Per 6 Inches

SAMPLE TYPES:

Martini Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-34
Logged By
Date Drilled
JTD Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
SM
SM
SC-SM
SC
SM
SW-SM
CO
B-1
R-1
R-2
R-3
R-4
Quaternary Alluvium (Qal); SILTY SAND, light gray, dry to moist, fine to medium grained sand Pauba Formation (Qps); SILTY SAND, dense, dark yellowish brown, moist, fine to coarse grained sand
SILTY, CLAYEY SAND, medium dense, olive brown, moist, fine to medium grained sand
CLAYEY SAND, dark yellowish brown, moist, fine to medium grained sand
SILTY SAND, medium dense, olive brown, moist, fine grained sand, iron oxide staining
Well-graded SAND with SILT, medium dense, olive brown to dark grayish brown, moist to wet, fine to coarse grained sand Drilled to 16.5' Sampled to 16.5' Groundwater not encountered Backfilled with Cuttings 26 28
33 7
7 12
5 7
11 14
19 13
~1080'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
JTD
Hollow Stem Auger - 140lb - Autohammer - 30" Drop Soil Class. 8-15-14

SOIL DESCRIPTION
Sampled By
Drilling Co.

Project
Project No.

See Plate 1
Proposed CarMax, Murrieta
10791.002
Drilling Method
8" Sample No. Feet
Hole Diameter Moisture
Ground Elevation
Depth
0 5
10 15
20 25
30 Blows Elevation Per 6 Inches

SAMPLE TYPES:

CalPac Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-38
Logged By
Date Drilled
JTD Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
SW-SM
SC-SM
SW-SM
SM
SC-SM
CO
R-1
R-2
R-3
R-4
Quaternary Alluvium (Qal); SILTY SAND, grayish brown, dry to moist, fine to coarse grained sand Pauba Formation (Qps); Well-graded SAND with SILT, olive brown and dark grayish brown, moist, fine to coarse grained sand SILTY, CLAYEY SAND, medium dense, dark yellowish brown, moist, fine to medium grained sand Well-graded SAND with SILT, dark grayish brown, moist, fine to coarse grained sand
SILTY SAND, medium dense, dark yellowish brown, moist, fine to coarse grained sand
SILTY SAND, medium dense, dark yellowish brown, moist, fine to coarse grained sand
SILTY, CLAYEY SAND, medium dense, dark yellowish brown, moist, fine to medium grained sand Total Depth = 21.5' bgs, no groundwater encountered, backfilled with cuttings on 08/15/14 6 12
13 6
8 13
10 13
25 5
12 24
~1081'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
JTD
Hollow Stem Auger - 140lb - Autohammer - 30" Drop Soil Class. 8-15-14

SOIL DESCRIPTION
Sampled By
Drilling Co.

Project
Project No.

See Plate 1
Proposed CarMax, Murrieta
10791.002
Drilling Method
8" Sample No. Feet
Hole Diameter Moisture
Ground Elevation
Depth
0 5
10 15
20 25
30 Blows Elevation Per 6 Inches

SAMPLE TYPES:

CalPac Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-39
Logged By
Date Drilled
JTD Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH
SM
R-1
R-2
R-3
Pauba Formation (Qps); SILTY SAND with GRAVEL, pale brown, dry to moist, fine to coarse grained sand SILTY SAND, yellowish brown, moist, fine to medium grained sand
SILTY SAND, dense, light brown, dry to moist, fine to medium grained sand, few caliche
SILTY SAND, olive brown, moist, fine to medium grained sand SILTY SAND, dense, reddish brown, moist, fine to coarse grained sand
SILTY SAND, dense, olive brown, moist, fine grained sand Total Depth = 21.5' bgs, no groundwater encountered, backfilled with cuttings on 08/15/14 14 20
37 19
23 46
15 29
34 ~1112'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
JTD
Hollow Stem Auger - 140lb - Autohammer - 30" Drop Soil Class. 8-15-14

SOIL DESCRIPTION
Sampled By
Drilling Co.

Project
Project No.

See Plate 1
Proposed CarMax, Murrieta
10791.002
Drilling Method
8" Sample No. Feet
Hole Diameter Moisture
Ground Elevation
Depth
0 5
10 15
20 25
30 Blows Elevation Per 6 Inches

SAMPLE TYPES:

CalPac Drilling
* * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Content, % GEOTECHNICAL BORING LOG LB-40
Logged By
Date Drilled
JTD Feet
S (U.S.C.S.)
Log
Type of Tests
Graphic
pcf
Location
Dry Density
N
This Soil Description applies only to a location of the exploration at the time of sampling. Subsurface conditions may differ at other locations and may change with time. The description is a simplification of the actual conditions encountered. Transitions between soil types may be gradual.

TYPE OF TESTS:
-200
AL
CN
CO
CR
CU
% FINES PASSING

ATTERBERG LIMITS

CONSOLIDATION

COLLAPSE

CORROSION

UNDRAINED TRIAXIAL
DS
EI
H
MD
PP
RV

DIRECT SHEAR

EXPANSION INDEX

HYDROMETER

MAXIMUM DENSITY

POCKET PENETROMETER

R VALUE
SA
SE
SG
UC

SIEVE ANALYSIS

SAND EQUIVALENT

SPECIFIC GRAVITY

UNCONFINED COMPRESSIVE STRENGTH

APPENDIX B

RESULTS OF GEOTECHNICAL LABORATORY TESTING
Project Name: Tested By: F. Mina Date: 04/11/23
Project No. : Input By: M. Vinet Date: 04/12/23
Boring No.: Checked By: M. Vinet
Sample No.: Depth (ft.) 0 - 5.0
Soil Identification:
1 2 1 2 3 4
15 23 35

23.70 23.82 19.30 21.69 20.03

22.66 22.81 18.14 20.02 18.75

13.80 13.68 13.85 13.66 13.62

11.74 11.06 27.04 26.26 24.95
26 11
15 CL
PI at "A" - Line = 0.73(LL-20) 4.38
One - Point Liquid Limit Calculation
LL =Wn(N/25)

PROCEDURES USED
Wet Preparation
Multipoint - Wet
X Dry Preparation
Multipoint - Dry
X Procedure A
Multipoint Test
Procedure B
One-point Test
Clayey Sand (SC), Yellowish Brown.

ATTERBERG LIMITS
ASTM D 4318
10791.006
LB-7
B-1
CarMax Murrieta Expansion
Dry Wt. of Soil + Cont. (g)
Wt. of Container (g)
Moisture Content (%) [Wn]
TEST
NO.

Liquid Limit
Plastic Limit
Plasticity Index
Classification
Number of Blows [N]
Wet Wt. of Soil + Cont. (g)

PLASTIC LIMIT LIQUID LIMIT
0 10
20 30
40 50
60 0 10 20 30 40 50 60 70 80 90 100
Plasticity Index (PI)
Liquid Limit (LL)

0.121
CL or OL
ML or OL
MH or OH
For classification of finegrained soils and finegrained fraction of coarsegrained soils "A" Line
7 4
CH or OH
CL- ML
22 23
24 25
26 27
28 29
10 100
Moisture Content (%)
Number of Blows
20 25 30 40 50 60 70 80 90
Project Name: Tested By: F. Mina Date: 4/10/23
Project No.: Checked By: M. Vinet Date: 4/12/23
Boring No.: LB-4 Sample Type: IN SITU
Sample No.: R-2 Depth (ft.) 2.5
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 111.0 Final Dry Density (pcf): 113.3 Initial Moisture (%): 11.0 Final Moisture (%) : 15.0
Initial Height (in.): 1.0000 Initial Void ratio: 0.5183 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 57.3

0.375 0.9916 0.00 -0.84 -0.84

0.750 0.9863 0.00 -1.37 -1.37
H2O 0.9800 0.00 -2.00 -2.00
Rev. 01-10
Potential of Cohesive Soils

0.0200 0.4879
Clayey Sand (SC), Dark Yellowish Brown.
10791.006

0.0137
Final Reading
(in)
Load
Compliance
(%)
Percent Swell / Settlement After Inundation = -0.64
(ASTM D 4546) -- Method 'B'
Swell (+)
Settlement (-)
% of Sample
Thickness
One-Dimensional Swell or Settlement
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.5055

0.4975
Apparent
Thickness
(in)
Void Ratio
CarMax Murrieta Expansion

0.0084
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Project Name: Tested By: F. Mina Date: 4/10/23
Project No.: Checked By: M. Vinet Date: 4/12/23
Boring No.: LB-7 Sample Type: IN SITU
Sample No.: R-2 Depth (ft.) 2.5
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 111.5 Final Dry Density (pcf): 113.6 Initial Moisture (%): 13.9 Final Moisture (%) : 15.5
Initial Height (in.): 1.0000 Initial Void ratio: 0.5115 Initial Dial Reading (in): 0.0000 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.416 Initial Degree of Saturation (%): 73.6

0.375 0.9867 0.00 -1.33 -1.33

0.750 0.9769 0.00 -2.31 -2.31
H2O 0.9814 0.00 -1.86 -1.86
Rev. 01-10
Potential of Cohesive Soils

0.0186 0.4834
Clayey Sand (SC), Dark Yellowish Brown.
10791.006

0.0231
Final Reading
(in)
Load
Compliance
(%)
Percent Swell / Settlement After Inundation = 0.46
(ASTM D 4546) -- Method 'B'
Swell (+)
Settlement (-)
% of Sample
Thickness
One-Dimensional Swell or Settlement
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.4914

0.4766
Apparent
Thickness
(in)
Void Ratio
CarMax Murrieta Expansion

0.0133
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
Tested By: F. Mina Date: 03/31/23
Input By: M. Vinet Date: 04/12/23
LB-2 Depth (ft.): 0 - 5.0
X Moist Mechanical Ram
Dry Manual Ram
Mold Volume (ft³) 0.03340 Ram Weight = 10 lb.; Drop = 18 in. 1 2 3 4 5 6
5585 5663 5663 5581
3523 3523 3523 3523
2062 2140 2140 2058
1320.2 1410.3 1410.5 1329.7
1259.4 1325.0 1305.9 1215.4
280.2 278.9 277.7 279.5

6.2 8.2 10.2 12.2
136.1 141.3 141.3 135.8
128.1 130.6 128.2 121.1
130.6 8.2

PROCEDURE USED
X Procedure A
Soil Passing No. 4 (4.75 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers : 5 (Five)
Blows per layer : 25 (twenty-five)
May be used if +#4 is 20% or less
Procedure B
Soil Passing 3/8 in. (9.5 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers : 5 (Five)
Blows per layer : 25 (twenty-five)
Use if +#4 is >20% and +3/8 in. is
20% or less
Procedure C
Soil Passing 3/4 in. (19.0 mm) Sieve
Mold : 6 in. (152.4 mm) diameter
Layers : 5 (Five)
Blows per layer : 56 (fifty-six)
Use if +3/8 in. is >20% and +¾ in.
is <30%
Particle-Size Distribution:

GR:SA:FI
Atterberg Limits:

LL,PL,PI

MODIFIED PROCTOR COMPACTION TEST
ASTM D 1557
Project No.:

Boring No.:

Project Name: CarMax Murrieta Expansion
Weight of Container (g)
Weight of Mold (g)
Preparation Method:

Wt. Compacted Soil + Mold (g)
B-1
10791.006
TEST NO.

Soil Identification:

Sample No.:

Clayey Sand (SC), Dark Yellowish Brown.

Maximum Dry Density (pcf) Optimum Moisture Content (%)
Net Weight of Soil (g)
Wet Density (pcf)
Dry Density (pcf)
Moisture Content (%)
Wet Weight of Soil + Cont. (g)
Dry Weight of Soil + Cont. (g)
115.0
120.0
125.0
130.0
135.0

0.0 5.0 10.0 15.0 20.

Dry Density (pcf)
Moisture Content (%)
SP. GR. = 2.65
SP. GR. = 2.70
SP. GR. = 2.75
XX
Compaction; LB-2, B-1 (03-27-23)
Tested By: F. Mina Date: 03/31/23
Input By: M. Vinet Date: 04/12/23
LB-6 Depth (ft.): 0 - 5.0
X Moist Mechanical Ram
Dry Manual Ram
Mold Volume (ft³) 0.03340 Ram Weight = 10 lb.; Drop = 18 in. 1 2 3 4 5 6
5585 5670 5678 5610
3523 3523 3523 3523
2062 2147 2155 2087
1230.2 1305.2 1311.2 1280.2
1176.2 1229.4 1217.5 1172.5
277.6 278.2 280.4 277.6

6.0 8.0 10.0 12.0
136.1 141.7 142.2 137.8
128.4 131.3 129.3 123.0
131.3 8.0

PROCEDURE USED
X Procedure A
Soil Passing No. 4 (4.75 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers : 5 (Five)
Blows per layer : 25 (twenty-five)
May be used if +#4 is 20% or less
Procedure B
Soil Passing 3/8 in. (9.5 mm) Sieve
Mold : 4 in. (101.6 mm) diameter
Layers : 5 (Five)
Blows per layer : 25 (twenty-five)
Use if +#4 is >20% and +3/8 in. is
20% or less
Procedure C
Soil Passing 3/4 in. (19.0 mm) Sieve
Mold : 6 in. (152.4 mm) diameter
Layers : 5 (Five)
Blows per layer : 56 (fifty-six)
Use if +3/8 in. is >20% and +¾ in.
is <30%
Particle-Size Distribution:
2:65:33
GR:SA:FI
Atterberg Limits:

LL,PL,PI

MODIFIED PROCTOR COMPACTION TEST
ASTM D 1557
Project No.:

Boring No.:

Project Name: CarMax Murrieta Expansion
Weight of Container (g)
Weight of Mold (g)
Preparation Method:

Wt. Compacted Soil + Mold (g)
B-1
10791.006
TEST NO.

Soil Identification:

Sample No.:

Clayey Sand (SC), Yellowish Brown.

Maximum Dry Density (pcf) Optimum Moisture Content (%)
Net Weight of Soil (g)
Wet Density (pcf)
Dry Density (pcf)
Moisture Content (%)
Wet Weight of Soil + Cont. (g)
Dry Weight of Soil + Cont. (g)
115.0
120.0
125.0
130.0
135.0

0.0 5.0 10.0 15.0 20.

Dry Density (pcf)
Moisture Content (%)
SP. GR. = 2.65
SP. GR. = 2.70
SP. GR. = 2.75
XX
Compaction; LB-6, B-1 (03-27-23)
Project Name: CarMax Murrieta Expansion Tested By : F. Mina Date: 04/12/23 Project No. : 10791.006 Data Input By: M. Vinet Date: 04/12/23 Boring No. LB-7
Sample No. B-1
Sample Depth (ft) 0 - 5.0
100.00
100.00

0.00 0.00
100.00
1 1
850
Timer
45 25.0400

25.0362

0.0038
156.37
156
ml of Extract For Titration (B) 30
ml of AgNO3 Soln. Used in Titration (C) 0.6
PPM of Chloride (C -0.2) * 100 * 30 / B 40
PPM of Chloride, Dry Wt. Basis 40

7.40 21.0
CHLORIDE CONTENT, DOT California Test 422
Wt. of Crucible (g)
PPM of Sulfate, Dry Weight Basis
PPM of Sulfate (A) x 41150
Wet Weight of Soil + Container (g)
Wt. of Residue (g) (A)
Moisture Content (%)
Beaker No.

Crucible No.

Furnace Temperature (°C)
Time In / Time Out
Weight of Soaked Soil (g)
Clayey Sand
(SC)
Wt. of Crucible + Residue (g)
Dry Weight of Soil + Container (g)
Weight of Container (g)
Duration of Combustion (min)
Temperature °C
pH Value
pH TEST, DOT California Test 643
TESTS for SULFATE CONTENT
CHLORIDE CONTENT and pH of SOILS
SULFATE CONTENT, DOT California Test 417, Part II
Soil Identification:

Project Name: Tested By : F. Mina Date:

Project No. : Data Input By: M. Vinet Date:

Boring No.: Depth (ft.) :

Sample No. : B-1
Container No.

Initial Soil Wt. (g) (Wt)
Box Constant
Clayey Sand (SC)
Resistance
Reading
(ohm)

16.60 Soil
Resistivity
(ohm-cm)
CarMax Murrieta Expansion 04/12/23
04/12/23
0 - 5.0
10791.006
LB-7

SOIL RESISTIVITY TEST
DOT CA TEST 643
pH Temp. (°C)
Soil pH
3000
3100
100.00

0.00 MC =(((1+Mci/100)x(Wa/Wt+1))-1)x100
2950 18.5 156 40 7.40 21.0
4 83
116
A
3 23.20 3100 500.00
3000
Min. Resistivity
DOT CA Test 417 Part II DOT CA Test 422 DOT CA Test 643 (%) (ppm) (ppm)
DOT CA Test 643

1.000
Chloride Content
(ohm-cm)
Moisture Content Sulfate Content
5 1
2 Water
Added (ml)
(Wa)
50 Adjusted
Moisture
Content
(MC) Dry Wt. of Soil + Cont. (g)
4000
Soil Identification:*
*California Test 643 requires soil specimens to consist only of portions of samples passing through the No. 8 US Standard Sieve before resistivity testing. Therefore, this test method may not be representative for coarser materials.

10.00 4000 Wt. of Container (g)

0.00 100.00
Moisture Content (%) (MCi)
Wet Wt. of Soil + Cont. (g)
Specimen
No.
0 500
1000
1500
2000
2500
3000
3500
4000
4500

0.0 5.0 10.0 15.0 20.0 25.0
Soil Resistivity (ohm-cm)
Moisture Content (%)
Minimum resistivity
read here
Project Name: Tested By: F. Mina Date: 4/10/23
Project No. : Checked By: M. Vinet Date: 4/12/23
Boring No.: Depth: 0 - 5.0
Sample No. : Location:

Sample Description:

Dry Wt. of Soil + Cont. (gm.)
Wt. of Container No. (gm.)
Dry Wt. of Soil (gm.)
Weight Soil Retained on #4 Sieve
Percent Passing # 4
in distilled water for the period of 24 h or expansion rate < 0.0002 in./h.

Rev. 03-08

SPECIMEN INUNDATION

65.1 Dry Wt. of Soil + Cont. (gm.)

8.5 351.0
327.5

0.459

51.0 180.8
622.6
131.7
Elapsed Time
(min.)
Dial Readings
(in.)

50.0 86.9
Pressure
(psi)
Total Porosity 0.314

2.70 383.1
180.8

15.3 0.322

67.5 EXPANSION INDEX of SOILS
Clayey Sand (SC), Dark Yellowish Brown.

MOLDED SPECIMEN

4.01 1.0000
Container No. 11
Specimen Diameter (in.)
Wt. Comp. Soil + Mold (gm.)
180.8
N/A
CarMax Murrieta Expansion
10791.006
LB-4
B-1
ASTM D 4829

98.9 4.01

2.70 2439.5

0.0 596.5
2439.5

27.2 1.0116
622.6
Before Test After Test
Wet Wt. of Soil + Cont. (gm.)
11 0.476
Dry Density (pcf)
Wet Density (pcf)
Specific Gravity (Assumed)
Specimen Height (in.)
Wt. of Mold (gm.)
4/10/23
115.6
Moisture Content (%)
Date
10:30
Void Ratio
Pore Volume (cc)
Degree of Saturation (%) [ S meas]
125.4
Time
4/11/23 9:00

1.0 1.0
4/10/23 10:40 1.0

1.0 Expansion Index ( Report ) = Nearest Whole Number or Zero (0) if Initial Height is > than Final Height 12 Add Distilled Water to the Specimen
Wt. of Container (gm.)
114.2

0.5000
10 0.5000
4/11/23 0.5116
0 1280
Expansion Index (EI meas) = ((Final Rdg - Initial Rdg) / Initial Thick.) x 1000 8:00
1340 0.5116

11.6 Project Name: Tested By: F. Mina Date: 4/10/23
Project No. : Checked By: M. Vinet Date: 4/12/23
Boring No.: Depth: 0 - 5.0
Sample No. : Location:

Sample Description:

Dry Wt. of Soil + Cont. (gm.)
Wt. of Container No. (gm.)
Dry Wt. of Soil (gm.)
Weight Soil Retained on #4 Sieve
Percent Passing # 4
in distilled water for the period of 24 h or expansion rate < 0.0002 in./h.

Rev. 03-08

SPECIMEN INUNDATION

68.8 Dry Wt. of Soil + Cont. (gm.)

9.0 349.9
325.1

0.498

49.9 190.5
625.4
129.1
Elapsed Time
(min.)
Dial Readings
(in.)

48.8 85.5
Pressure
(psi)
Total Porosity 0.332

2.70 373.2
190.5

16.5 0.343

72.2 EXPANSION INDEX of SOILS
Clayey Sand (SC), Dark Yellowish Brown.

MOLDED SPECIMEN

4.01 1.0000
Container No. 12
Specimen Diameter (in.)
Wt. Comp. Soil + Mold (gm.)
190.5
N/A
CarMax Murrieta Expansion
10791.006
LB-7
B-1
ASTM D 4829

98.5 4.01

2.70 2291.2

0.0 597.3
2291.2

34.8 1.0165
625.4
Before Test After Test
Wet Wt. of Soil + Cont. (gm.)
12 0.522
Dry Density (pcf)
Wet Density (pcf)
Specific Gravity (Assumed)
Specimen Height (in.)
Wt. of Mold (gm.)
4/10/23
112.6
Moisture Content (%)
Date
11:00
Void Ratio
Pore Volume (cc)
Degree of Saturation (%) [ S meas]
122.7
Time
4/11/23 9:00

1.0 1.0
4/10/23 11:10 1.0

0.0 Expansion Index ( Report ) = Nearest Whole Number or Zero (0) if Initial Height is > than Final Height 17 Add Distilled Water to the Specimen
Wt. of Container (gm.)
110.8

0.5000
10 0.5000
4/11/23 0.5165
0 1250
Expansion Index (EI meas) = ((Final Rdg - Initial Rdg) / Initial Thick.) x 1000 8:00
1310 0.5165

16.5 Project Name: Date: 4/6/23
Project Number: 10791.006 Technician: F. Mina
Boring Number: LB-2 Depth (ft.): 0 - 5.0
Sample Number: B-1
Sample Description:

TEST SPECIMEN A B C
MOISTURE AT COMPACTION % 9.1 10.2 11.6
HEIGHT OF SAMPLE, Inches 2.50 2.50 2.51
DRY DENSITY, pcf 118.0 118.0 116.1
COMPACTOR AIR PRESSURE, psi 200 175 145
EXUDATION PRESSURE, psi 579 411 277
EXPANSION, Inches x 10exp-4 46 28 12
STABILITY Ph 2,000 lbs (160 psi) 44 84 125
TURNS DISPLACEMENT 4.00 4.25 4.60
R-VALUE UNCORRECTED 62 35 13
R-VALUE CORRECTED 62 35 13
DESIGN CALCULATION DATA a b c
GRAVEL EQUIVALENT FACTOR 1.0 1.0 1.0
TRAFFIC INDEX 5.0 5.0 5.0
STABILOMETER THICKNESS, ft. 0.60 1.04 1.39
EXPANSION PRESSURE THICKNESS, ft. 1.74 1.06 0.45

EXPANSION PRESSURE CHART EXUDATION PRESSURE CHART
R-VALUE BY EXPANSION: 34
R-VALUE BY EXUDATION: 17
EQUILIBRIUM R-VALUE: 17

R-VALUE TEST RESULTS
ASTM D 2844
CarMax Murrieta Expansion
Clayey Sand (SC), Dark Yellowish Brown. Sample Location: N/A

0.00 0.50

1.00 1.50

2.00 2.50

3.00 3.50

4.00 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00
COVER THICKNESS BY EXPANSION in
feet
COVER THICKNESS BY STABILOMETER in
feet
0 10
20 30
40 50
60 70
80 90
800 700 600 500 400 300 200 100 0

R-VALUE
EXUDATION PRESSURE (psi)
Project Name: Tested By: FLM Date: 04/10/23
Project No.: 10791.006 Checked By: MRV Date: 04/12/23
Boring No.: LB-6 Depth (feet): 0 - 5.0
Sample No.: B-1
Soil Identification: Clayey Sand (SC), Yellowish Brown.

Whole Sample Sample Passing
#4 Whole Sample Sample passing #4
P P Wt. of Air-Dry Soil + Cont.(g) 1277.3 1034.5
1277.3 1034.5 Wt. of Dry Soil + Cont. (g) 1226.4 1034.5 716.2 716.2 Wt. of Container No._____(g) 716.2 716.2
510.1 318.3 Moisture Content (%) 10.0 0.0
P
931.0
716.2
214.8
(mm.)
1 1/2"
1"
3/4"
1/2"
3/8"
#4
#8
#16
#30
#50
#100
#200
GRAVEL: 2 %
SAND: 65 %
FINES: 33 %
GROUP SYMBOL: SC N/A
N/A
Remarks:
210.5

43.3 76.9
117.1
165.2

0.075
PAN

0.0 2.1

4.750 7.5

2.360

1.180

0.600

0.300

0.150
Passing #4 Material After Wet Sieve

37.500
U. S. Sieve Size

25.000

19.000

12.500

9.500
Whole Sample

99.6 100.0

98.5 93.8

33.4 100.0

62.3 47.4
Wt. Air-Dried Soil + Cont.(g)
100.0
Cumulative Weight of Dry Soil Retained (g)
Sample Passing #4

PARTICLE-SIZE DISTRIBUTION (GRADATION)
ASTM D 6913
Container No.:

CarMax Murrieta Expansion
Moisture Contents Calculation of Dry Weights
of SOILS USING SIEVE ANALYSIS
Dry Wt. of Soil (g)
Wt. of Container (g)
Container No.
100.0

85.1 74.7
Percent Passing
(%)
Wt. of Dry Soil + Container (g)
Wt. of Container (g)
Dry Wt. of Soil Retained on # 200 Sieve (g)

15.3 Cu = D60/D10 =
Cc = (D30)²/(D60*D10) =
2 : 65 : 33
B-1
Apr-23
Boring No.:

Depth (feet): 0 - 5.0 Soil Type :

Project Name:

PARTICLE - SIZE

DISTRIBUTION
ASTM D 6913
Soil Identification: Clayey Sand (SC), Yellowish Brown.

SC
GR:SA:FI : (%)
CarMax Murrieta Expansion
Project No.:

LB-6 Sample No.:
10791.006
SAND

FINE SILT

HYDROMETER

3.0" 1 1/2" 3/4" 3/8" #4 #8 #16 #30 #50 #100 #200
U.S. STANDARD SIEVE OPENING U.S. STANDARD SIEVE NUMBER

GRAVEL FINES

COARSE FINE COARSE MEDIUM CLAY
0 10
20 30
40 50
60 70
80 90
100
100.000 10.000 1.000 0.100 0.010 0.001

PERCENT FINER BY WEIGHT
PARTICLE - SIZE (mm)
"
Sieve; LB-6, B-1 (03-27-23)
One-Dimensional Swell or Settlement
Potential of Cohesive Soils
(ASTM D 4546) -- Method 'B'
Project Name: Tested By: MRV Date: 9/3/14
Project No.: Checked By: JHW Date: 9/8/14
Boring No.: LB-38 Sample Type: IN SITU
Sample No.: R-3 Depth (ft.) 15.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 105.0 Final Dry Density (pcf): 107.6 Initial Moisture (%): 10.4 Final Moisture (%) : 16.7
Initial Height (in.): 0.9960 Initial Void ratio: 0.6056 Initial Dial Reading (in): 0.0500 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.429 Initial Degree of Saturation (%): 46.2

1.050 0.9854 0.00 -1.06 -1.06

2.013 0.9781 0.00 -1.80 -1.80
H2O 0.9695 0.00 -2.66 -2.66
-0.88
Rev. 01-10
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.5886

0.5768
Final Reading
(in) Void Ratio
Carmax Geo

0.5629

0.0646

0.0719

0.0805
Silty Sand (SM), brown.
10791.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water
One-Dimensional Swell or Settlement
Potential of Cohesive Soils
(ASTM D 4546) -- Method 'B'
Project Name: Tested By: MRV Date: 9/3/14
Project No.: Checked By: JHW Date: 9/8/14
Boring No.: LB-39 Sample Type: IN SITU
Sample No.: R-2 Depth (ft.) 10.0
Sample Description:

Source and Type of Water Used for Inundation: Arrowhead ( Distilled ) ** Note: Loading After Wetting (Inundation) not Performed Using this Test Method.

Initial Dry Density (pcf): 112.0 Final Dry Density (pcf): 116.5 Initial Moisture (%): 14.6 Final Moisture (%) : 15.9
Initial Height (in.): 0.9930 Initial Void ratio: 0.5055 Initial Dial Reading (in): 0.0500 Specific Gravity (assumed): 2.70 Inside Diameter of Ring (in): 2.421 Initial Degree of Saturation (%): 77.8

1.050 0.9775 0.00 -1.56 -1.56

2.013 0.9694 0.00 -2.38 -2.38
H2O 0.9640 0.00 -2.92 -2.92
-0.56
Rev. 01-10
Percent Swell / Settlement After Inundation =
Corrected
Deformation
(%)
Pressure (p)
(ksf)

0.4820

0.4698
Final Reading
(in) Void Ratio
Carmax Geo

0.4616

0.0725

0.0806

0.0860
Silty Sand (SM), brown.
10791.002
Swell (+)
Settlement (-)
% of Sample
Thickness
Load
Compliance
(%)
Apparent
Thickness
(in)
-5.00
-4.00
-3.00
-2.00
-1.00

0.00 1.00

2.00 3.00

4.00 5.00

0.010 0.100 1.000 10.000
Deformation %
Log Pressure (ksf)
Deformation % - Log Pressure Curve
Inundate With
Distilled Water

APPENDIX C

EARTHWORK AND GRADING SPECIFICATIONS

APPENDIX D
LEIGHTON CONSULTING, INC.

EARTHWORK AND GRADING GUIDE SPECIFICATIONS

TABLE OF CONTENTS
Section Appendix D Page
D-1.0 GENERAL ........................................................................................................... 1 D-1.1 Intent ............................................................................................................. 1 D-1.2 Role of Leighton Consulting, Inc. ................................................................... 1 D-1.3 The Earthwork Contractor ............................................................................. 1 D-2.0 PREPARATION OF AREAS TO BE FILLED ..................................................... 2 D-2.1 Clearing and Grubbing .................................................................................. 2 D-2.2 Processing ..................................................................................................... 3 D-2.3 Overexcavation ............................................................................................. 3 D-2.4 Benching ....................................................................................................... 3 D-2.5 Evaluation/Acceptance of Fill Areas .............................................................. 3 D-3.0 FILL MATERIAL ................................................................................................. 4 D-3.1 Fill Quality ...................................................................................................... 4 D-3.2 Oversize ........................................................................................................ 4 D-3.3 Import ............................................................................................................ 4 D-4.0 FILL PLACEMENT AND COMPACTION ........................................................... 4 D-4.1 Fill Layers ...................................................................................................... 4 D-4.2 Fill Moisture Conditioning .............................................................................. 5 D-4.3 Compaction of Fill .......................................................................................... 5 D-4.4 Compaction of Fill Slopes .............................................................................. 5 D-4.5 Compaction Testing ...................................................................................... 5 D-4.6 Compaction Test Locations ........................................................................... 5 D-5.0 EXCAVATION ..................................................................................................... 6 D-6.0 TRENCH BACKFILLS ........................................................................................ 6 D-6.1 Safety ............................................................................................................ 6 D-6.2 Bedding and Backfill ...................................................................................... 6 D-6.3 Lift Thickness ................................................................................................ 7 Standard Detail
Retaining Wall Rear of Text
D-1
D-1.0 GENERAL
D-1.1 Intent
These Earthwork and Grading Guide Specifications are for grading and earthwork shown on the current, approved grading plan(s) and/or indicated in the Leighton Consulting, Inc. geotechnical report(s). These Guide Specifications are a part of the recommendations contained in the geotechnical report(s). In case of conflict, the project-specific recommendations in the geotechnical report shall supersede these Guide Specifications. Leighton Consulting, Inc. shall provide geotechnical observation and testing during earthwork and grading. Based on these observations and tests, Leighton Consulting, Inc. may provide new or revised recommendations that could supersede these specifications or the recommendations in the geotechnical report(s).

D-1.2 Role of Leighton Consulting, Inc.

Prior to commencement of earthwork and grading, Leighton Consulting, Inc. shall meet with the earthwork contractor to review the earthwork contractor’s work plan, to schedule sufficient personnel to perform the appropriate level of observation, mapping and compaction testing. During earthwork and grading, Leighton Consulting, Inc. shall observe, map, and document subsurface exposures to verify geotechnical design assumptions. If observed conditions are found to be significantly different than the interpreted assumptions during the design phase, Leighton Consulting, Inc. shall inform the owner, recommend appropriate changes in design to accommodate these observed conditions, and notify the review agency where required. Subsurface areas to be geotechnically observed, mapped, elevations recorded, and/or tested include (1) natural ground after clearing to receiving fill but before fill is placed, (2) bottoms of all "remedial removal" areas, (3) all key bottoms, and (4) benches made on sloping ground to receive fill.

Leighton Consulting, Inc. shall observe moisture-conditioning and processing of the subgrade and fill materials, and perform relative compaction testing of fill to determine the attained relative compaction. Leighton Consulting, Inc. shall provide Daily Field Reports to the owner and the Contractor on a routine and frequent basis.

D-1.3 The Earthwork Contractor
The earthwork contractor (Contractor) shall be qualified, experienced and knowledgeable in earthwork logistics, preparation and processing of ground to receive fill, moisture-conditioning and processing of fill, and compacting fill. The Contractor shall review and accept the plans, geotechnical report(s), and these Guide Leighton Consulting, Inc. Earthwork and Grading Guide Specifications D-2
Specifications prior to commencement of grading. The Contractor shall be solely responsible for performing grading and backfilling in accordance with the current, approved plans and specifications.

The Contractor shall inform the owner and Leighton Consulting, Inc. of changes in work schedules at least one working day in advance of such changes so that appropriate observations and tests can be planned and accomplished. The Contractor shall not assume that Leighton Consulting, Inc. is aware of all grading operations.

The Contractor shall have the sole responsibility to provide adequate equipment and methods to accomplish earthwork and grading in accordance with the applicable grading codes and agency ordinances, these Guide Specifications, and recommendations in the approved geotechnical report(s) and grading plan(s). If, in the opinion of Leighton Consulting, Inc., unsatisfactory conditions, such as unsuitable soil, improper moisture condition, inadequate compaction, adverse weather, etc., are resulting in a quality of work less than required in these specifications, Leighton Consulting, Inc. shall reject the work and may recommend to the owner that earthwork and grading be stopped until unsatisfactory condition(s) are rectified.

D-2.0 PREPARATION OF AREAS TO BE FILLED
D-2.1 Clearing and Grubbing
Vegetation, such as brush, grass, roots and other deleterious material shall be sufficiently removed and properly disposed of in a method acceptable to the owner, governing agencies and Leighton Consulting, Inc.. Care should be taken not to encroach upon or otherwise damage native and/or historic trees designated by the Owner or appropriate agencies to remain. Pavements, flatwork or other construction should not extend under the “drip line” of designated trees to remain.

Leighton Consulting, Inc. shall evaluate the extent of these removals depending on specific site conditions. Earth fill material shall not contain more than 3 percent of organic materials (by dry weight: ASTM D 2974). Nesting of the organic materials shall not be allowed.

If potentially hazardous materials are encountered, the Contractor shall stop work in the affected area, and a hazardous material specialist shall be informed immediately for proper evaluation and handling of these materials prior to continuing to work in that area. As presently defined by the State of California, most refined petroleum products (gasoline, diesel fuel, motor oil, grease, coolant, etc.) have chemical constituents that Leighton Consulting, Inc. Earthwork and Grading Guide Specifications D-3
are considered to be hazardous waste. As such, the indiscriminate dumping or spillage of these fluids onto the ground may constitute a misdemeanor, punishable by fines and/or imprisonment, and shall not be allowed.

D-2.2 Processing
Existing ground that has been declared satisfactory for support of fill, by Leighton Consulting, Inc., shall be scarified to a minimum depth of 6 inches (15 cm). Existing ground that is not satisfactory shall be over-excavated as specified in the following Section D-2.3. Scarification shall continue until soils are broken down and free of large clay lumps or clods and the working surface is reasonably uniform, flat, and free of uneven features that would inhibit uniform compaction.

D-2.3 Overexcavation
In addition to removals and over-excavations recommended in the approved geotechnical report(s) and the grading plan, soft, loose, dry, saturated, spongy, organicrich, highly fractured or otherwise unsuitable ground shall be over-excavated to competent ground as evaluated by Leighton Consulting, Inc. during grading. All undocumented fill soils under proposed structure footprints should be excavated D-2.4 Benching
Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical units), (>20 percent grade) the ground shall be stepped or benched. The lowest bench or key shall be a minimum of 15 feet (4.5 m) wide and at least 2 feet (0.6 m) deep, into competent material as evaluated by Leighton Consulting, Inc.. Other benches shall be excavated a minimum height of 4 feet (1.2 m) into competent material or as otherwise recommended by Leighton Consulting, Inc.. Fill placed on ground sloping flatter than 5:1 (horizontal to vertical units), (<20 percent grade) shall also be benched or otherwise over-excavated to provide a flat subgrade for the fill.

D-2.5 Evaluation/Acceptance of Fill Areas
All areas to receive fill, including removal and processed areas, key bottoms, and benches, shall be observed, mapped, elevations recorded, and/or tested prior to being accepted by Leighton Consulting, Inc. as suitable to receive fill. The Contractor shall obtain a written acceptance (Daily Field Report) from Leighton Consulting, Inc. prior to fill placement. A licensed surveyor shall provide the survey control for determining elevations of processed areas, keys and benches.

Leighton Consulting, Inc. Earthwork and Grading Guide Specifications D-4
D-3.0 FILL MATERIAL
D-3.1 Fill Quality
Material to be used as fill shall be essentially free of organic matter and other deleterious substances evaluated and accepted by Leighton Consulting, Inc. prior to placement. Soils of poor quality, such as those with unacceptable gradation, high expansion potential, or low strength shall be placed in areas acceptable to Leighton Consulting, Inc. or mixed with other soils to achieve satisfactory fill material.

D-3.2 Oversize
Oversize material defined as rock, or other irreducible material with a maximum dimension greater than 6 inches (15 cm), shall not be buried or placed in fill unless location, materials and placement methods are specifically accepted by Leighton Consulting, Inc.. Placement operations shall be such that nesting of oversized material does not occur and such that oversize material is completely surrounded by compacted or densified fill. Oversize material shall not be placed within 10 feet (3 m) measured vertically from finish grade, or within 2 feet (0.61 m) of future utilities or underground construction.

D-3.3 Import
If importing of fill material is required for grading, proposed import material shall meet the requirements of Section D-3.1, and be free of hazardous materials (“contaminants”) and rock larger than 3-inches (8 cm) in largest dimension. All import soils shall have an Expansion Index (EI) of 20 or less and a sulfate content no greater than () 500 partsper-million (ppm). A representative sample of a potential import source shall be given to Leighton Consulting, Inc. at least four full working days before importing begins, so that suitability of this import material can be determined and appropriate tests performed.

D-4.0 FILL PLACEMENT AND COMPACTION
D-4.1 Fill Layers
Approved fill material shall be placed in areas prepared to receive fill, as described in Section D-2.0, above, in near-horizontal layers not exceeding 8 inches (20 cm) in loose thickness. Leighton Consulting, Inc. may accept thicker layers if testing indicates the grading procedures can adequately compact the thicker layers, and only if the building officials with the appropriate jurisdiction approve. Each layer shall be spread evenly and mixed thoroughly to attain relative uniformity of material and moisture throughout.

Leighton Consulting, Inc. Earthwork and Grading Guide Specifications D-5
D-4.2 Fill Moisture Conditioning
Fill soils shall be watered, dried back, blended and/or mixed, as necessary to attain a relatively uniform moisture content at or slightly over optimum. Maximum density and optimum soil moisture content tests shall be performed in accordance with the American Society of Testing and Materials (ASTM) Test Method D 1557.

D-4.3 Compaction of Fill
After each layer has been moisture-conditioned, mixed, and evenly spread, each layer shall be uniformly compacted to not-less-than (≥) 90 percent of the maximum dry density as determined by ASTM Test Method D 1557. In some cases, structural fill may be specified (see project-specific geotechnical report) to be uniformly compacted to atleast (≥) 95 percent of the ASTM D 1557 modified Proctor laboratory maximum dry density. For fills thicker than (>) 15 feet (4.5 m), the portion of fill deeper than 15 feet below proposed finish grade shall be compacted to 95 percent of the ASTM D 1557 laboratory maximum density. Compaction equipment shall be adequately sized and be either specifically designed for soil compaction or of proven reliability to efficiently achieve the specified level of compaction with uniformity.

D-4.4 Compaction of Fill Slopes
In addition to normal compaction procedures specified above, compaction of slopes shall be accomplished by back rolling of slopes with sheepsfoot rollers at increments of 3 to 4 feet (1 to 1.2 m) in fill elevation, or by other methods producing satisfactory results acceptable to Leighton Consulting, Inc.. Upon completion of grading, relative compaction of the fill, out to the slope face, shall be at least 90 percent of the ASTM D 1557 laboratory maximum density.

D-4.5 Compaction Testing
Field-tests for moisture content and relative compaction of the fill soils shall be performed by Leighton Consulting, Inc.. Location and frequency of tests shall be at our field representative(s) discretion based on field conditions encountered. Compaction test locations will not necessarily be selected on a random basis. Test locations shall be selected to verify adequacy of compaction levels in areas that are judged to be prone to inadequate compaction (such as close to slope faces and at the fill/bedrock benches).

D-4.6 Compaction Test Locations
Leighton Consulting, Inc. shall document the approximate elevation and horizontal coordinates of each density test location. The Contractor shall coordinate with the project surveyor to assure that sufficient grade stakes are established so that Leighton Leighton Consulting, Inc. Earthwork and Grading Guide Specifications D-6
Consulting, Inc. can determine the test locations with sufficient accuracy. Adequate grade stakes shall be provided.

D-5.0 EXCAVATION
Excavations, as well as over-excavation for remedial purposes, shall be evaluated by Leighton Consulting, Inc. during grading. Remedial removal depths shown on geotechnical plans are estimates only. The actual extent of removal shall be determined by Leighton Consulting, Inc. based on the field evaluation of exposed conditions during grading. Where fill-over-cut slopes are to be graded, the cut portion of the slope shall be made, then observed and reviewed by Leighton Consulting, Inc. prior to placement of materials for construction of the fill portion of the slope, unless otherwise recommended by Leighton Consulting, Inc..

D-6.0 TRENCH BACKFILLS
D-6.1 Safety
The Contractor shall follow all OSHA and Cal/OSHA requirements for safety of trench excavations. Work should be performed in accordance with Article 6 of the California Construction Safety Orders, 2009 Edition or more current (see also:
http://www.dir.ca.gov/title8/sb4a6.html ).

D-6.2 Bedding and Backfill
All utility trench bedding and backfill shall be performed in accordance with applicable provisions of the 2015 Edition of the Standard Specifications for Public Works Construction (Green Book). Bedding material shall have a Sand Equivalent greater than 30 (SE>30). Bedding shall be placed to 1-foot (0.3 m) over the top of the conduit, and densified by jetting in areas of granular soils, if allowed by the permitting agency.

Otherwise, the pipe-bedding zone should be backfilled with Controlled Low Strength Material (CLSM) consisting of at least one sack of Portland cement per cubic-yard of sand, and conforming to Section 201-6 of the 2015 Edition of the Standard Specifications for Public Works Construction (Green Book). Backfill over the bedding zone shall be placed and densified mechanically to a minimum of 90 percent of relative compaction (ASTM D 1557) from 1 foot (0.3 m) above the top of the conduit to the surface. Backfill above the pipe zone shall not be jetted. Jetting of the bedding around the conduits shall be observed by Leighton Consulting, Inc. and backfill above the pipe zone (bedding) shall be observed and tested by Leighton Consulting, Inc..

Leighton Consulting, Inc. Earthwork and Grading Guide Specifications D-7
D-6.3 Lift Thickness
Lift thickness of trench backfill shall not exceed those allowed in the Standard Specifications of Public Works Construction unless the Contractor can demonstrate to Leighton Consulting, Inc. that the fill lift can be compacted to the minimum relative compaction by his alternative equipment and method, and only if the building officials with the appropriate jurisdiction approve.

RETAINING WALL BACKFILL AND SUBDRAIN DETAIL

WITH PROPER

SURFACE DRAINAGE
SLOPE

OR LEVEL
CLASS 2 PERMEABLE

WEEP HOLE

WATERPROOFING
(SEE GENERAL NOTES)

LEVEL OR
SLOPE
12"

FILTER MATERIAL
NATIVE
¼ TO 1½ INCH SIZE GRAVEL WRAPPED IN FILTER FABRIC

LEVEL OR
SLOPE

WEEP HOLE
SLOPE

OR LEVEL
12"

WITH PROPER

SURFACE DRAINAGE
4 INCH DIAMETER

PERFORATED PIPE
(SEE NOTE 3)

FILTER FABRIC
OPTION 1: PIPE SURROUNDED WITH
CLASS 2 PERMEABLE MATERIAL OPTION 2: GRAVEL WRAPPED

IN FILTER FABRIC
SUBDRAIN OPTIONS AND BACKFILL WHEN NATIVE MATERIAL HAS EXPANSION INDEX OF <50 Sieve Size
1"
3/4"
3/8"
No. 4
No. 8
No. 30
No. 50
No. 200
Percent Passing
100
90-100
40-100
25-40
18-33
5-15
0-7
0-3
Class 2 Filter Permeable Material Gradation
Per Caltrans Specifications
(SEE NOTE 5)
12" MINIMUM
(SEE GRADATION)

WATERPROOFING
(SEE GENERAL NOTES)
(SEE NOTE 4)
12" MINIMUM
NATIVE
FOR WALLS 6 FEET OR LESS IN HEIGHT
(SEE NOTE 5)
WHEN NATIVE MATERIAL HAS EXPANSION INDEX OF <50
GENERAL NOTES:
* Waterproofing should be provided where moisture nuisance problem through the wall is undesirable. * Water proofing of the walls is not under purview of the geotechnical engineer * All drains should have a gradient of 1 percent minimum *Outlet portion of the subdrain should have a 4-inch diameter solid pipe discharged into a suitable disposal area designed by the project engineer. The subdrain pipe should be accessible for maintenance (rodding) *Other subdrain backfill options are subject to the review by the geotechnical engineer and modification of design parameters.

Notes:
1) Sand should have a sand equivalent of 30 or greater and may be densified by water jetting. 2) 1 Cu. ft. per ft. of 1/4- to 1 1/2-inch size gravel wrapped in filter fabric 3) Pipe type should be ASTM D1527 Acrylonitrile Butadiene Styrene (ABS) SDR35 or ASTM D1785 Polyvinyl Chloride plastic (PVC), Schedule 40, Armco A2000 PVC, or approved equivalent. Pipe should be installed with perforations down. Perforations should be 3/8 inch in diameter placed at the ends of a 120-degree arc in two rows at 3-inch on center (staggered) 4) Filter fabric should be Mirafi 140NC or approved equivalent. 5) Weephole should be 3-inch minimum diameter and provided at 10-foot maximum intervals. If exposure is permitted, weepholes should be located 12 inches above finished grade. If exposure is not permitted such as for a wall adjacent to a sidewalk/curb, a pipe under the sidewalk to be discharged through the curb face or equivalent should be provided. For a basement-type wall, a proper subdrain outlet system should be provided.
6) Retaining wall plans should be reviewed and approved by the geotechnical engineer. 7) Walls over six feet in height are subject to a special review by the geotechnical engineer and modifications to the above requirements.

V:\DRAFTING\TEMPLATES\STANDARD-FIGURES\ALL-STANDARD-FIGURES.DWG (08-02-21 9:07:35AM) Plotted by: btran

APPENDIX D
GBA - IMPORTANT INFORMATION ABOUT THIS GEOTECHNICALENGINEERING REPORT Geotechnical-Engineering Report
Important Information about This
Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes.

While you cannot eliminate all such risks, you can manage them. The following information is provided to help.

The Geoprofessional Business Association (GBA)
has prepared this advisory to help you – assumedly
a client representative – interpret and apply this
geotechnical-engineering report as effectively as
possible. In that way, you can benefit from a lowered
exposure to problems associated with subsurface
conditions at project sites and development of
them that, for decades, have been a principal cause
of construction delays, cost overruns, claims,
and disputes. If you have questions or want more
information about any of the issues discussed herein,
contact your GBA-member geotechnical engineer.

Active engagement in GBA exposes geotechnical
engineers to a wide array of risk-confrontation
techniques that can be of genuine benefit for
everyone involved with a construction project.

Understand the Geotechnical-Engineering Services
Provided for this Report
Geotechnical-engineering services typically include the planning, collection, interpretation, and analysis of exploratory data from widely spaced borings and/or test pits. Field data are combined with results from laboratory tests of soil and rock samples obtained from field exploration (if applicable), observations made during site reconnaissance, and historical information to form one or more models of the expected subsurface conditions beneath the site. Local geology and alterations of the site surface and subsurface by previous and proposed construction are also important considerations. Geotechnical engineers apply their engineering training, experience, and judgment to adapt the requirements of the prospective project to the subsurface model(s). Estimates are made of the subsurface conditions that will likely be exposed during construction as well as the expected performance of foundations and other structures being planned and/or affected by construction activities.

The culmination of these geotechnical-engineering services is typically a geotechnical-engineering report providing the data obtained, a discussion of the subsurface model(s), the engineering and geologic engineering assessments and analyses made, and the recommendations developed to satisfy the given requirements of the project. These reports may be titled investigations, explorations, studies, assessments, or evaluations.

Regardless of the title used, the geotechnical-engineering report is an engineering interpretation of the subsurface conditions within the context of the project and does not represent a close examination, systematic inquiry, or thorough investigation of all site and subsurface conditions.

Geotechnical-Engineering Services are Performed
for Specific Purposes, Persons, and Projects,
and At Specific Times
Geotechnical engineers structure their services to meet the specific needs, goals, and risk management preferences of their clients. A geotechnical-engineering study conducted for a given civil engineer will not likely meet the needs of a civil-works constructor or even a different civil engineer. Because each geotechnical-engineering study is unique, each geotechnical-engineering report is unique, prepared solely for the client.

Likewise, geotechnical-engineering services are performed for a specific project and purpose. For example, it is unlikely that a geotechnicalengineering study for a refrigerated warehouse will be the same as one prepared for a parking garage; and a few borings drilled during a preliminary study to evaluate site feasibility will not be adequate to develop geotechnical design recommendations for the project.

Do not rely on this report if your geotechnical engineer prepared it:
• for a different client;
• for a different project or purpose;
• for a different site (that may or may not include all or a portion of the original site); or
• before important events occurred at the site or adjacent to it; e.g., man-made events like construction or environmental remediation, or natural events like floods, droughts, earthquakes, or groundwater fluctuations.

Note, too, the reliability of a geotechnical-engineering report can be affected by the passage of time, because of factors like changed subsurface conditions; new or modified codes, standards, or regulations; or new techniques or tools. If you are the least bit uncertain about the continued reliability of this report, contact your geotechnical engineer before applying the recommendations in it. A minor amount of additional testing or analysis after the passage of time – if any is required at all – could prevent major problems.

Read this Report in Full
Costly problems have occurred because those relying on a geotechnicalengineering report did not read the report in its entirety. Do not rely on an executive summary. Do not read selective elements only. Read and refer to the report in full.

You Need to Inform Your Geotechnical Engineer
About Change
Your geotechnical engineer considered unique, project-specific factors when developing the scope of study behind this report and developing the confirmation-dependent recommendations the report conveys.

Typical changes that could erode the reliability of this report include those that affect:
• the site’s size or shape;
• the elevation, configuration, location, orientation,
function or weight of the proposed structure and
the desired performance criteria;
• the composition of the design team; or
• project ownership.

As a general rule, always inform your geotechnical engineer of project or site changes – even minor ones – and request an assessment of their impact. The geotechnical engineer who prepared this report cannot accept responsibility or liability for problems that arise because the geotechnical engineer was not informed about developments the engineer otherwise would have considered.

Most of the “Findings” Related in This Report
Are Professional Opinions
Before construction begins, geotechnical engineers explore a site’s subsurface using various sampling and testing procedures. Geotechnical engineers can observe actual subsurface conditions only at those specific locations where sampling and testing is performed. The data derived from that sampling and testing were reviewed by your geotechnical engineer, who then applied professional judgement to form opinions about subsurface conditions throughout the site. Actual sitewide-subsurface conditions may differ – maybe significantly – from those indicated in this report. Confront that risk by retaining your geotechnical engineer to serve on the design team through project completion to obtain informed guidance quickly, whenever needed.

This Report’s Recommendations Are
Confirmation-Dependent
The recommendations included in this report – including any options or alternatives – are confirmation-dependent. In other words, they are not final, because the geotechnical engineer who developed them relied heavily on judgement and opinion to do so. Your geotechnical engineer can finalize the recommendations only after observing actual subsurface conditions exposed during construction. If through observation your geotechnical engineer confirms that the conditions assumed to exist actually do exist, the recommendations can be relied upon, assuming no other changes have occurred. The geotechnical engineer who prepared this report cannot assume responsibility or liability for confirmation-dependent recommendations if you fail to retain that engineer to perform construction observation.

This Report Could Be Misinterpreted
Other design professionals’ misinterpretation of geotechnicalengineering reports has resulted in costly problems. Confront that risk by having your geotechnical engineer serve as a continuing member of the design team, to:
• confer with other design-team members;
• help develop specifications;
• review pertinent elements of other design professionals’ plans and specifications; and
• be available whenever geotechnical-engineering guidance is needed.

You should also confront the risk of constructors misinterpreting this report. Do so by retaining your geotechnical engineer to participate in prebid and preconstruction conferences and to perform constructionphase observations.

Give Constructors a Complete Report and Guidance
Some owners and design professionals mistakenly believe they can shift unanticipated-subsurface-conditions liability to constructors by limiting the information they provide for bid preparation. To help prevent the costly, contentious problems this practice has caused, include the complete geotechnical-engineering report, along with any attachments or appendices, with your contract documents, but be certain to note conspicuously that you’ve included the material for information purposes only. To avoid misunderstanding, you may also want to note that “informational purposes” means constructors have no right to rely on the interpretations, opinions, conclusions, or recommendations in the report. Be certain that constructors know they may learn about specific project requirements, including options selected from the report, only from the design drawings and specifications. Remind constructors that they may perform their own studies if they want to, and be sure to allow enough time to permit them to do so. Only then might you be in a position to give constructors the information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. Conducting prebid and preconstruction conferences can also be valuable in this respect.

Read Responsibility Provisions Closely
Some client representatives, design professionals, and constructors do not realize that geotechnical engineering is far less exact than other engineering disciplines. This happens in part because soil and rock on project sites are typically heterogeneous and not manufactured materials with well-defined engineering properties like steel and concrete. That lack of understanding has nurtured unrealistic expectations that have resulted in disappointments, delays, cost overruns, claims, and disputes.

To confront that risk, geotechnical engineers commonly include explanatory provisions in their reports. Sometimes labeled “limitations,” many of these provisions indicate where geotechnical engineers’ responsibilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions.

Your geotechnical engineer should respond fully and frankly.

Geoenvironmental Concerns Are Not Covered
The personnel, equipment, and techniques used to perform an environmental study – e.g., a “phase-one” or “phase-two” environmental site assessment – differ significantly from those used to perform a geotechnical-engineering study. For that reason, a geotechnical-engineering report does not usually provide environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated subsurface environmental problems have led to project failures. If you have not obtained your own environmental information about the project site, ask your geotechnical consultant for a recommendation on how to find environmental risk-management guidance.

Obtain Professional Assistance to Deal with
Moisture Infiltration and Mold
While your geotechnical engineer may have addressed groundwater, water infiltration, or similar issues in this report, the engineer’s services were not designed, conducted, or intended to prevent migration of moisture – including water vapor – from the soil through building slabs and walls and into the building interior, where it can cause mold growth and material-performance deficiencies.

Accordingly, proper implementation of the geotechnical engineer’s recommendations will not of itself be sufficient to prevent moisture infiltration. Confront the risk of moisture infiltration by including building-envelope or mold specialists on the design team.

Geotechnical engineers are not building-envelope or mold specialists.

Copyright 2019 by Geoprofessional Business Association (GBA). Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA’s specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes of scholarly research or book review. Only members of GBA may use this document or its wording as a complement to or as an element of a report of any kind.

Any other firm, individual, or other entity that so uses this document without being a GBA member could be committing negligent or intentional (fraudulent) misrepresentation.

Telephone: 301/565-2733
e-mail: [email protected] www.geoprofessional.org 60 8 °
10:47:00
11:17:00
11:18:00
11:48:00
11:48:00
12:18:00
12:18:00
12:48:00
Tested by: DM Date Tested 6/30/2023
Soil Unit: SM Depth of Test Hole (in.)
Test Hole Number: P-1 Project CarMax Murrieta
Date Excavated: 6/27/2023 Project Number 10791.007
inches/hour* minute/inch

30.00 12.13 16.38 4.25 0.36 7
USCS Soil Type: Silty SAND (SM) Diameter (in.) Sunny ~75 Time Δt (min) Initial Water Depth
(inches)
Final Water Depth
(inches)
Change In Water Level
(inches)
Infiltration/Percolation
Rate

30.00 11.50 15.00 3.50 0.29 9

30.00 11.88 15.25 3.37 0.28 9

30.00 11.88 15.25 3.37 0.28 9
Date: Jun-23
* Based on Prochet Method
Percolation Project Number: 10791.007
Test Data
Project Name: CarMax Murrieta
P-1

0.00 0.05

0.10 0.15

0.20 0.25

0.30 0.35

0.40 0 10 20 30 40 50 60 70 80 90 100
Infiltration Rate
(in./hr)
Time (min)
120
8 °
14:11:00
14:41:00
14:43:00
15:13:00
15:13:00
15:43:00
15:43:00
16:10:00
Tested by: DM Date Tested 6/30/2023
Soil Unit: SM Depth of Test Hole (in.)
Test Hole Number: P-2 Project CarMax Murrieta
Date Excavated: 6/27/2023 Project Number 10791.007
inches/hour* minute/inch

30.00 102.36 104.52 2.16 0.47 14
USCS Soil Type: Silty SAND Diameter (in.) Sunny ~75
Time Δt (min) Initial Water Depth
(inches)
Final Water Depth
(inches)
Change In Water Level
(inches)
Infiltration/Percolation
Rate

30.00 93.60 96.00 2.40 0.35 13

30.00 94.80 97.20 2.40 0.37 13

30.00 92.40 94.80 2.40 0.34 13
Date: Jun-23
* Based on Prochet Method
Percolation Project Number: 10791.007
Test Data
Project Name: CarMax Murrieta
P-2

0.00 0.05

0.10 0.15

0.20 0.25

0.30 0.35

0.40 0.45

0.50 0 10 20 30 40 50 60 70 80 90 100
Infiltration Rate
(in./hr)
Time (min)
120
8 °
14:16:00
14:46:00
14:50:00
15:20:00
15:20:00
15:50:00
15:50:00
16:20:00
Tested by: JGS Date Tested 6/30/2023
Soil Unit: DM Depth of Test Hole (in.)
Test Hole Number: P-3 Project CarMax Murrieta
Date Excavated: 6/27/2023 Project Number 10791.007
inches/hour* minute/inch

30.00 91.32 94.20 2.88 0.39 10
USCS Soil Type: Silty SAND Diameter (in.) Sunny ~75
Time Δt (min) Initial Water Depth
(inches)
Final Water Depth
(inches)
Change In Water Level
(inches)
Infiltration/Percolation
Rate

30.00 90.00 92.04 2.04 0.26 15

30.00 89.16 91.20 2.04 0.26 15

30.00 87.60 89.64 2.04 0.24 15
Date: Jun-23
* Based on Prochet Method
Percolation Project Number: 10791.007
Test Data
Project Name: CarMax Murrieta
P-3

0.00 0.05

0.10 0.15

0.20 0.25

0.30 0.35

0.40 0.45
0 10 20 30 40 50 60 70 80 90 100
Infiltration Rate
(in./hr)
Time (min)
60 8 °
10:34:00
11:04:00
11:04:00
11:34:00
11:38:00
12:08:00
12:08:00
12:38:00
12:39:00
13:09:00
13:10:00
13:40:00
13:40:00
14:10:00
Tested by: DM Date Tested 6/30/2023
Soil Unit: SC-SM Depth of Test Hole (in.)
Test Hole Number: P-4 Project CarMax Murrieta
Date Excavated: 6/27/2023 Project Number 10791.007
inches/hour* minute/inch

30.00 10.25 10.63 0.38 0.03 79
USCS Soil Type: Silty Clayey SAND Diameter (in.) Sunny ~75 Time Δt (min) Initial Water Depth
(inches)
Final Water Depth
(inches)
Change In Water Level
(inches)
Infiltration/Percolation
Rate

30.00 10.25 11.00 0.75 0.06 40

30.00 10.63 11.63 1.00 0.08 30

30.00 10.25 10.38 0.13 0.01 231

30.00 10.13 10.50 0.37 0.03 81

30.00 10.25 10.38 0.13 0.01 231

30.00 10.25 10.38 0.13 0.01 231
Date: Jun-23
* Based on Prochet Method
Percolation Project Number: 10791.007
Test Data
Project Name: CarMax Murrieta
P-4

0.00 0.01

0.02 0.03

0.04 0.05

0.06 0.07

0.08 0.09
0 50 100 150 200 250
Infiltration Rate
(in./hr)
Time (min)
120
8 °
14:04:00
14:34:00
14:35:00
15:05:00
15:05:00
15:35:00
15:36:00
16:06:00
Tested by: JGS Date Tested 6/30/2023
Soil Unit: SM Depth of Test Hole (in.)
Test Hole Number: P-5 Project CarMax Murrieta
Date Excavated: 6/27/2023 Project Number 10791.007
inches/hour* minute/inch

30.00 85.20 97.20 12.00 1.56 3
USCS Soil Type: Silty SAND Diameter (in.) Sunny ~75
Time Δt (min) Initial Water Depth
(inches)
Final Water Depth
(inches)
Change In Water Level
(inches)
Infiltration/Percolation
Rate

30.00 88.80 97.56 8.76 1.22 3

30.00 90.84 99.48 8.64 1.29 3

30.00 90.00 99.00 9.00 1.31 3
Date: Jun-23
* Based on Prochet Method
Percolation Project Number: 10791.007
Test Data
Project Name: CarMax Murrieta
P-5

0.00 0.20

0.40 0.60

0.80 1.00

1.20 1.40

1.60 1.80
0 10 20 30 40 50 60 70 80 90 100
Infiltration Rate
(in./hr)
Time (min)
60 8 °
10:22:00
10:52:00
10:53:00
11:23:00
11:24:00
11:54:00
11:55:00
12:25:00
12:25:00
12:55:00
Tested by: DM Date Tested 6/30/2023
Soil Unit: SM Depth of Test Hole (in.)
Test Hole Number: P-6 Project CarMax Murrieta
Date Excavated: 6/27/2023 Project Number 10791.007
inches/hour* minute/inch

30.00 10.75 12.50 1.75 0.14 17
USCS Soil Type: Silty SAND Diameter (in.) Sunny ~75
Time Δt (min) Initial Water Depth
(inches)
Final Water Depth
(inches)
Change In Water Level
(inches)
Infiltration/Percolation
Rate

30.00 10.13 11.25 1.12 0.09 27

30.00 10.75 12.38 1.63 0.13 18

30.00 10.13 11.25 1.12 0.09 27

30.00 10.13 11.25 1.12 0.09 27
Date: Jun-23
* Based on Prochet Method
Percolation Project Number: 10791.007
Test Data
Project Name: CarMax Murrieta
P-6

0.00 0.02

0.04 0.06

0.08 0.10

0.12 0.14

0.16 0 20 40 60 80 100 120 140 160 180
Infiltration Rate
(in./hr)
Time (min)
Water Quality Management Plan (WQMP)
CarMax Murrieta #1824
52 Appendix 4: Historical Site
Conditions
Phase I Environmental Site Assessment or Other Information on Past Site Use Project Specific Water Quality Management Plan
A Template for preparing Project Specific WQMPs for Priority Development Projects located within the Santa Margarita Region of Riverside County
Project Title: CarMax Automotive Dealership ‐ Murrieta
Development No: N/A
Design Review/Case No: N/A
Original Date Prepared: Sept 2014
Revision Date(s):

Prepared for Compliance with
Regional Board Order No. R9‐2010‐0016
Contact Information:

Prepared for:

Centerpoint Integrated Solutions, LLC
1240 Bergen kwy, Ste A‐250
Evergreen, CO 80439
Prepared by:

Hall & Foreman, Inc.
17782 17th St, Ste 200
Tustin, CA 92780
Preliminary
Final
A Brief Introduction
The Municipal Separate Stormwater Sewer System (MS4) Permit1 for the Santa Margarita Region (SMR) requires preparation of a Project‐Specific Water Quality Management Plan (WQMP) for all Development Projects as defined in section F.1.d.(1) of the Permit.   This Project‐Specific WQMP Template for Development Projects in the Santa Margarita Region has been prepared to help document compliance and prepare a WQMP submittal. Below is a flowchart for the layout of this Template that will provide the steps required to document compliance.

1 Order No. R9‐2010‐0016, NPDES No. CAS0108766, Waste Discharge Requirements for Discharges from the MS4 Draining the County of Riverside, the Incorporated Cities of Riverside County, and the Riverside County Flood Control and Water Conservation District within the San Diego Region, California Regional Water Quality Control Board,  November 10, 2010.

Section A
•Project and Site Information
•Identification of LID and
Hydromodification
requirements, if any
Section B
•Optimize Site Utilization
Section C
•Delineate Drainage
Management Areas (DMAs)
Section D
•Technical Feasibility
•Implement LID BMPs
Section E
•Technical Feasibility
•Implement
Hydromodification BMPs
Section F
•Alternative Compliance (LID
Waiver Program &
Hydromodification)
Section G
•Source Control BMPs
Section H
•Operation, Maintenance,
and Funding
Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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OWNER’S CERTIFICATION
This Project‐Specific WQMP has been prepared for Centerpoint Integrated Solutions, LLC by Hall & Foreman for the CarMax Automotive Dealership project.

This WQMP is intended to comply with the requirements of The City of Murrieta for State Board Order No. 2009‐ 0009‐DWQ (NPDES No. CAS000002) which includes the requirement for the preparation and implementation of a Project‐Specific WQMP.

The undersigned, while owning the property/project described in the preceding paragraph, shall be responsible for the implementation and funding of this WQMP and will ensure that this WQMP is amended as appropriate to reflect up‐to‐date conditions on the site.   In addition, the property owner accepts responsibility for interim operation and maintenance of Stormwater Best Management Practices until such time as this responsibility is formally transferred to a subsequent owner. This WQMP will be reviewed with the facility operator, facility supervisors, employees, tenants, maintenance and service contractors, or any other party (or parties) having responsibility for implementing portions of this WQMP.  At least one copy of this WQMP will be maintained at the project site or project office in perpetuity. The undersigned is authorized to certify and to approve implementation of this WQMP.   The undersigned is aware that implementation of this WQMP is enforceable under The City of Murrieta Water Quality Ordinance (Municipal Code Section 2010‐0016). "I, the undersigned, certify under penalty of law that the provisions of this WQMP have been reviewed and accepted and that the WQMP will be transferred to future successors in interest."

Owner’s Signature           Date

Owner’s Printed Name             Owner’s Title/Position PREPARER’S CERTIFICATION
“The selection, sizing and design of stormwater treatment and other stormwater quality and quantity control Best Management Practices in this plan meet the requirements of Regional Water Quality Control Board Order No. R9‐ 2010‐0016 and any subsequent amendments thereto.”

02/18/2015
Preparer’s Signature           Date

Glenn M. Chung   Principal, P.E.

Preparer’s Printed Name             Preparer’s Title/Position

Preparer’s Licensure:    PE #62794
Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Table of Contents
Section A: Project and Site Information........................................................................................................ 6 A.1 Maps and Site Plans............................................................................................................................ 6 A.2 Identify Receiving Waters................................................................................................................... 7 A.3 Drainage System Susceptibility to Hydromodification ....................................................................... 7 A.4 Additional Permits/Approvals required for the Project: .................................................................... 8 Section B: Optimize Site Utilization (LID Principles) ..................................................................................... 9 Section C: Delineate Drainage Management Areas (DMAs)....................................................................... 10 Section D: Implement LID BMPs................................................................................................................. 13 D.1 Infiltration Applicability .................................................................................................................... 13 D.2 Harvest and Use Assessment............................................................................................................ 15 D.3 Bioretention and Biotreatment Assessment.................................................................................... 17 D.4 Other Limiting Geotechnical Conditions........................................................................................... 18 D.5 Feasibility Assessment Summaries................................................................................................... 18 D.6 LID BMP Sizing ..................................................................................................................................19 Section E: Implement Hydrologic Control BMPs and Sediment Supply BMPs ........................................... 20 E.1 Onsite Feasibility of Hydrologic Control BMPs.................................................................................. 20 E.2 Meeting the HMP Performance Standard for Small Project Sites.................................................... 21 E.3 Hydrologic Control BMP Selection .................................................................................................... 21 E.4 Hydrologic Control BMP Sizing.......................................................................................................... 22 E.5 Implement Sediment Supply BMPs................................................................................................... 23 Section F: Alternative Compliance.............................................................................................................. 26 F.1 Identify Pollutants of Concern........................................................................................................... 28 F.2 Stormwater Credits........................................................................................................................... 29 F.3 Sizing Criteria.....................................................................................................................................29 F.4 Treatment Control BMP Selection .................................................................................................... 30 F.5 Hydrologic Performance Standard – Alternative Compliance Approach.......................................... 30 F.6 Sediment Supply Performance Standard ‐ Alternative Compliance ................................................. 31 Section G: Source Control BMPs................................................................................................................. 32 Section H: Construction Plan Checklist....................................................................................................... 33 Section I: Operation, Maintenance and Funding........................................................................................ 34 Acronyms, Abbreviations and Definitions .................................................................................................. 35

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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List of Tables
Table A.1 Identification of Receiving Waters................................................................................................ 7 Table A.2 Identification of Susceptibility to Hydromodification................................................................... 7 Table A.3 Other Applicable Permits.............................................................................................................. 8 Table C.1 DMA Classifications..................................................................................................................... 10 Table C.2 Type ‘A’, Self‐Treating Areas....................................................................................................... 10 Table C.3 Type ‘B’, Self‐Retaining Areas ..................................................................................................... 11 Table C.4 Type ‘C’, Areas that Drain to Self‐Retaining Areas...................................................................... 11 Table C.5 Type ‘D’, Areas Draining to BMPs ............................................................................................... 12 Table D.1 Infiltration Feasibility .................................................................................................................. 13 Table D.2 Geotechnical Concerns for Onsite Retention Table ................................................................... 18 Table D.3 LID Prioritization Summary Matrix ............................................................................................. 18 Table D.4 DCV Calculations for LID BMPs................................................................................................... 19 Table D.5 LID BMP Sizing............................................................................................................................. 20 Table E.1 LID & Hydromodification BMP Location...................................................................................... 22 Table E.2 Hydrologic Control BMP Sizing.................................................................................................... 22 Table F.1 Potential Pollutants by Land Use Type........................................................................................ 28 Table F.2 Stormwater Credits ..................................................................................................................... 29 Table F.3 Treatment Control BMP Sizing .................................................................................................... 29 Table F.4 Treatment Control BMP Selection............................................................................................... 30 Table F.5 Offsite Hydrologic Control BMP Sizing ........................................................................................ 31 Table G.1 Structural and Operational Source Control BMP........................................................................ 32 Table H.1 Construction Plan Cross‐reference ............................................................................................. 33 List of Appendices
Appendix 1: Maps and Site Plans................................................................................................................ 42 Appendix 2: Construction Plans.................................................................................................................. 43 Appendix 3: Soils Information..................................................................................................................... 44 Appendix 4: Historical Site Conditions........................................................................................................ 45 Appendix 5: LID Infeasibility........................................................................................................................ 46 Appendix 6: BMP Design Details................................................................................................................. 47 Appendix 7: Hydromodification.................................................................................................................. 48 Appendix 8: Source Control ........................................................................................................................ 49 Appendix 9: O&M .......................................................................................................................................50 Appendix 10: Educational Materials........................................................................................................... 43 Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Section A: Project and Site Information

PROJECT INFORMATION
Type of Project: Commercial
Planning Area: N/A
Community Name: N/A
Development Name: CarMax Automotive Dealership

PROJECT LOCATION
Latitude & Longitude (DMS): Lat  33°33'3.27"N, Long 117°11'28.45"W Project Watershed and Sub‐Watershed: San Diego Region ‐ Santa Margarita Region Watershed APN(s): 910‐140‐074‐1,2,3
Map Book and Page No.: 910‐140

PROJECT CHARACTERISTICS
Proposed or potential land use(s) New and used car
dealers; automotive
repair, services, and
parking; parking lot
Proposed or Potential SIC Code(s) 551; 7514; 7515; 7521; 7532; 7538; 7539; 7542;
7549
Area of Impervious Project Footprint (SF) 1,694,745
Total area of proposed Impervious Surfaces within the Project Limits (SF)/or Replacement 1,328,232 Total Project Area (ac) 38.88 ac
Does the project consist of offsite road improvements? Y N Does the project propose to construct unpaved roads? Y N Is the project part of a larger common plan of development (phased project)? Y N Is the project exempt from HMP Performance Standards? Y N

EXISTING SITE CHARACTERISTICS
Total area of existing Impervious Surfaces within the project limits (SF) 16,900 Is the project located within any Multi‐Species Habitat Conservation Plan (MSHCP Criteria Cell?
Y N
If so, identify the Cell number: N/A
Are there any natural hydrologic features on the project site? Y N Is a Geotechnical Report attached? Y N
If no Geotech. Report, list the Natural Resources Conservation Service (NRCS) soils type(s) present on the site (A, B, C and/or D)
N/A
What is the Water Quality Design Storm Depth for the project? 0.8 in/hr A.1 Maps and Site Plans
When completing your Project‐Specific WQMP, include a map of the Project vicinity and existing site. In addition, include all grading, drainage, landscape/plant palette and other pertinent construction plans in Appendix 2. At a minimum, your WQMP Site Plan should include the following:

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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 Drainage Management Areas (DMAs)
 Proposed Structural Best Management
Practices (BMPs)
 Drainage Path
 Drainage infrastructure, inlets, overflows
 Source Control BMPs
 Buildings, Roof Lines, Downspouts
 Impervious Surfaces
 Standard Labeling
Use your discretion on whether or not you may need to create multiple sheets or can appropriately accommodate these features on one or two sheets. Keep in mind that the Copermittee plan reviewer must be able to easily analyze your Project utilizing this template and its associated site plans and maps.

A.2 Identify Receiving Waters
Using Table A.1 below, list, in order of upstream to downstream, the Receiving Waters that the Project site is tributary to. Continue to fill each row with the Receiving Water’s 303(d) listed impairments (if any), designated Beneficial Uses, and proximity, if any, to a RARE Beneficial Use. Include a map of the Receiving Waters in Appendix 1. (http://www.waterboards.ca.gov/sandiego/water_issues/programs/basin_plan/) Table A.1 Identification of Receiving Waters
Receiving
Waters
USEPA Approved 303(d) List
Impairments
Designated
Beneficial Uses
Proximity to RARE
Beneficial Use
Murrieta Creek Phosphorus; chlorpyrifos; copper;
iron; manganese; nitrogen; toxicity
Warm freshwater habitat; water contact
recreation; municipal & domestic supply; municipal
& domestic supply
None
Santa Margarita
River (Upper) Phosphorus; toxicity Warm freshwater habitat None Santa Margarita
River (Lower)
Enterococcus; fecal coliform;
phosphorus; nitrogen
Municipal & domestic supply; water contact
recreation; warm freshswater habitat None
A.3 Drainage System Susceptibility to Hydromodification Using Table A.2 below, list in order of the point of discharge at the project site down to the Santa Margarita River, each drainage system or receiving water that the project site is tributary to. Continue to fill each row with the material of the drainage system, the storm drain susceptibility using the SWCT2 (Stormwater & Water Conservation Tracking Tool  ‐  http://rivco.permitrack.com/) or Map 2 of the Hydromodification Susceptibility Documentation Report and Mapping: Santa Margarita Region (Appendix D of the SMR HMP), and the condition for exempting the drainage system, if applicable. If the exemption includes receiving waters that were not evaluated in Appendix D, provide supporting documentation in Appendix 7 to demonstrate that they classify as Engineered, Fully Hardened and Maintained (EFHM) channels, consistent with the definition provided in Appendix D. Include a map exhibiting each drainage system and the associated susceptibility in Appendix 1.

Table A.2 Identification of Susceptibility to Hydromodification Drainage System Drainage System Material Susceptibility of Drainage System
Hydromodification
Exemption
Underground storm
drain pipe network Cast in place concrete pipe Potentially   Potentially Not Exempt Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Drainage System Drainage System Material Susceptibility of Drainage System
Hydromodification
Exemption
Above Ground
Discharge
Compavted soils with check dams and
natural cover Potentially Potentially Not Exempt
Murrieta Creek Compacted Soils and Gravel Portentially Potentially A.4 Additional Permits/Approvals required for the Project:

Table A.3 Other Applicable Permits
Agency Permit Required
State Department of Fish and Game, 1602 Streambed Alteration Agreement Y N State Water Resources Control Board, Clean Water Act Section 401 Water Quality Certification Y N
US Army Corps of Engineers, Clean Water Act Section 404 Permit Y N US Fish and Wildlife, Endangered Species Act Section 7 Biological Opinion Y N Statewide Construction General Permit Coverage Y N
Statewide Industrial General Permit Coverage Y N
Western Riverside MSHCP Consistency Approval (e.g., JPR, DBESP) Y N Other (please list in the space below as required)

N/A Y N
If yes is answered to any of the questions above, the Copermittee may require proof of approval/coverage from those agencies as applicable including documentation of any associated requirements that may affect this Project‐Specific WQMP.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Section B: Optimize Site Utilization (LID Principles)
Review of the information collected in Section ‘A’ will aid in identifying the principal constraints on site design and selection of LID BMPs as well as opportunities to reduce imperviousness and incorporate LID Principles into the site and landscape design.   For example, constraints might include impermeable soils, high groundwater, groundwater pollution or contaminated soils, steep slopes, geotechnical instability, high‐intensity land use, heavy pedestrian or vehicular traffic, utility locations or safety concerns.  Opportunities might include existing natural areas, low areas, oddly configured or otherwise unbuildable parcels, easements and landscape amenities including open space and buffers (which can double as locations for LID Bioretention BMPs), and differences in elevation (which can provide hydraulic head).  Prepare a brief narrative for each of the site optimization strategies described below.

This narrative will help you as you proceed with your Low Impact Development (LID) design and explain your design decisions to others.

The 2010 SMR MS4 Permit further requires that LID Retention BMPs (Infiltration Only or Harvest and Use) be used unless it can be shown that those BMPs are infeasible.  Therefore, it is important that your narrative identify and justify if there are any constraints that would prevent the use of those categories of LID BMPs.  Similarly, you should also note opportunities that exist which will be utilized during project design.  Upon completion of identifying Constraints and Opportunities, include these on your WQMP Site plan in Appendix 1.

Site Optimization
The following questions are based upon Section 3.2 of the WQMP Guidance Document. Review of the WQMP Guidance Document will help you determine how best to optimize your site and subsequently identify opportunities and/or constraints, and document compliance.

Did you identify and preserve existing drainage patterns? If so, how?  If not, why? Yes, existing site runoff will discharge to either the existing channel located onsite or the existing 108" CIP storm drain line.

Did you identify and protect existing vegetation? If so, how? If not, why? No, existing vegetation will be removed as part of the project site development. New landscaping will be installed throughout the site.

Did you identify and preserve natural infiltration capacity? If so, how? If not, why? Yes, the existing site utilized an engineered channel for infiltration which will be protected in place in development. Infiltration basins will also be constructed onsite to allow for natural infiltration.

Did you identify and minimize impervious area? If so, how? If not, why? No.  The site is an automotive storange and maintenance facility requiring paved areas for automotive transportation.

Did you identify and disperse runoff to adjacent pervious areas? If so, how? If not, why? Yes, paved areas will be drained towards a treatment control BMP and/or a detention basin.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Section C: Delineate Drainage Management Areas
(DMAs)
Utilizing the procedure in Section 3.3 of the WQMP Guidance Document which discusses the methods of delineating and mapping your project site into individual DMAs, complete Table C.1 below to appropriately categorize the types of classification (e.g., Type A, Type B, etc.) per DMA for your Project site. Upon completion of this table, this information will then be used to populate and tabulate the corresponding tables for their respective DMA classifications.

Table C.1 DMA Classifications
DMA Name or Identification Surface Type(s)1 Area (Sq. Ft.) DMA Type 1 Ornamental
Landscaping, Roofs,
Driveway, Sidewalks,
Parking
280,962 “C”
1a Landscaping/Vegetation 29,185 “B”
2 Ornamental
Landscaping, Roofs,
Driveway, Sidewalks,
Parking
192,535 “D”
3 Ornamental
Landscaping, Roofs,
Driveway, Sidewalks,
Parking
109,336 “C”
3a Landscaping/Vegetation 40,947 “B”
4 Ornamental
Landscaping, Roofs,
Driveway, Sidewalks,
Parking
434,730 “D”
5 Ornamental
Landscaping, Roofs,
Driveway, Sidewalks,
Parking
453,460 “C”
5a Landscaping/Vegetation 62,726 “B”
6 Ornamental
Landscaping, Roofs,
Driveway, Sidewalks,
Parking
90,170 “D”
1 Reference Table 2‐1 in the WQMP Guidance Document to populate this column Table C.2 Type ‘A’, Self‐Treating Areas
DMA Name or Identification Area (Sq. Ft.) Stabilization Type Irrigation Type (if any) N/A

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Table C.3 Type ‘B’, Self‐Retaining Areas
Self‐Retaining Area Type ‘C’ DMAs that are draining to the Self‐Retaining Area
DMA
Name/ ID
Post‐project
surface type
Area
(square
feet)
Storm
Depth
(inches)
DMA Name / ID
[C] from Table
C.4 =
Required Retention Depth
(inches)
[A] [B] [C] [D]
1a Vegetated Basin 29,185 0.80 1 238,817 7.35
3a Vegetated Basin 40,947 0.80 3 92,936 2.61
5a Vegetated Basin 62,726 0.80 5 317,422 4.85
ሾܦሿ ൌ ሾܤሿ ൅ ሾܤሿ ∙ ሾܥሿ
ሾܣሿ
Table C.4 Type ‘C’, Areas that Drain to Self‐Retaining Areas DMA Receiving Self‐Retaining DMA
DMA Name/ ID
Area
(square feet)
Post‐project
surface type
Runoff
factor
Product
DMA name /ID
Area (square
feet) Ratio
[A] [B] [C] = [A] x [B] [D] [C]/[D]
1 280,962 Roofs,
Driveway,
Sidewalks,
Parking,
Ornamental
Landscaping

0.85 238,817 1a
29,185

8.18 3 109,336 Roofs,
Driveway,
Sidewalks,
Parking,
Ornamental
Landscaping

0.85 92,936 3a
40,947

2.26 5 453,460 Roofs,
Driveway,
Sidewalks,
Parking,
Ornamental
Landscaping

0.70 317,422 5a
62,727

5.06 Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Note: (See Section 3.3 of WQMP Guidance Document) Ensure that partially pervious areas draining to a Self‐Retaining area do not exceed the following ratio:
൬ ૛
૚∶൰࢔࢕࢏࢚ࢉࢇ࢘ࡲ ࢙࢛࢕࢏࢜࢘ࢋ࢖࢓ࡵ
(Tributary Area: Self‐Retaining Area)
Table C.5 Type ‘D’, Areas Draining to BMPs
DMA Name or ID BMP Name or ID
2 Underground infiltration chambers
4 Flow thru planter
6 Flow thru planter

Note: More than one DMA may drain to a single LID BMP; however, one DMA may not drain to more than one BMP.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Section D: Implement LID BMPs
D.1 Infiltration Applicability
An assessment of the feasibility of utilizing Infiltration BMPs is required for all projects, except in the following case:
 Harvest and Use BMPs will be implemented to address the Design Capture Volume (see the Harvest and Use Assessment below) for all Drainage Management Areas AND the project is exempt from HMP Performance Standards (Proceed to Section D.2 and Section E).

If the above box remains unchecked, perform a site‐specific evaluation of the feasibility of Infiltration BMPs using each of the applicable criteria identified in Chapter 3.4.1 of the WQMP Guidance Document and complete the remainder of Section D.1.

Is there an infiltration concern (see discussion in Chapter 2.3.4 of the WQMP Guidance Document for further details)?   Y N
If yes has been checked, both Infiltration BMPs and Hydrologic Control BMPs that include an infiltration functionalities may not be feasible for the site. It is recommended that you contact your Copermittee to verify whether or not infiltration within the Project is infeasible.

Geotechnical Report
A Geotechnical Report or Phase I Environmental Site Assessment may be required by the Copermittee to confirm present and past site characteristics that may affect the use of Infiltration BMPs. In addition, the Copermittee, at their discretion, may not require a geotechnical report for small projects as described in Chapter 2 of the WQMP Guidance Document. If a geotechnical report has been prepared, include it in Appendix 3. In addition, if a Phase I Environmental Site Assessment has been prepared, include it in Appendix 4.

Is this project classified as a small project consistent with the requirements of Chapter 2 of the WQMP Guidance Document? Y N
Infiltration Feasibility
Table D.1 below is meant to provide a simple means of assessing which DMAs on your site support Infiltration BMPs and is discussed in the WQMP Guidance Document in Chapter 2.3.4. Check the appropriate box for each question and then list affected DMAs as applicable. If additional space is needed, add a row below the corresponding answer.

Table D.1 Infiltration Feasibility
Does the project site… YES NO
…have any DMAs with a seasonal high groundwater mark shallower than 10 feet?   X If Yes, list affected DMAs:
…have any DMAs located within 100 feet of a water supply well?   X If Yes, list affected DMAs:
…have any areas identified by the geotechnical report as posing a public safety risk where infiltration of stormwater could have a negative impact?
X
If Yes, list affected DMAs:
…have measured in‐situ infiltration rates of less than 1.6 inches / hour? X If Yes, list affected DMAs: Entire site is less than 1.6 in/hr Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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…have significant cut and/or fill conditions that would preclude in‐situ testing of infiltration rates at the final infiltration surface?
X
If Yes, list affected DMAs:
…have any contaminated groundwater plume in the vicinity of the site?   X If Yes, list affected DMAs:
…geotechnical report identifies other site‐specific factors that would preclude effective and safe infiltration?   X Describe here:

If you answered “Yes” to any of the questions above for any DMA, Infiltration BMPs should not be used for those DMAs and you should proceed to the assessment for Harvest and Use below.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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D.2 Harvest and Use Assessment
Please check what applies:
☒ Reclaimed water will be used for the non‐potable water demands for the Project. ☐Downstream water rights may be impacted by Harvest and Use as approved by the Regional Board (verify with the Copermittee).
☒The Design Capture Volume (DCV) will be addressed using Infiltration Only BMPs. In such a case, Harvest and Use BMPs are still encouraged, but it would not be required if the DCV will be infiltrated or evapotranspired.

If any of the above boxes have been checked, Harvest and Use BMPs need not be assessed for the site. If neither of the above criteria applies, follow the steps below to assess the feasibility of irrigation use, toilet use and other non‐potable uses (e.g., industrial use).

Irrigation Use Feasibility
Complete the following steps to determine the feasibility of harvesting stormwater runoff for Irrigation Use BMPs on your site:

Step 1: Identify the total area of irrigated landscape on the site, and the type of landscaping used.

Total Area of Irrigated Landscape: Area (Acres)
Type of Landscaping (Conservation Design or Active Turf): Conservation Design or Active Turf Step 2: Identify the planned total of all impervious areas on the proposed project from which runoff might be feasibly captured and stored for irrigation use. Depending on the configuration of buildings and other impervious areas on the site, you may consider the site as a whole, or parts of the site, to evaluate reasonable scenarios for capturing and storing runoff and directing the stored runoff to the potential use(s) identified in Step 1 above.

Total Area of Impervious Surfaces: Area (Acres)
Step 3: Cross reference the Design Storm depth for the project site (see Exhibit A of the WQMP Guidance Document) with the left column of Table 2‐4 in Chapter 2 to determine the minimum area of Effective Irrigated Area per Tributary Impervious Area (EIATIA).

Enter your EIATIA factor: EIATIA Factor
Step 4: Multiply the unit value obtained from Step 3 by the total of impervious areas from Step 2 to develop the minimum irrigated area that would be required.

Minimum required irrigated area: Acres
Step 5: Determine if harvesting stormwater runoff for irrigation use is feasible for the project by comparing the total area of irrigated landscape (Step 1) to the minimum required irrigated area (Step 4).

Minimum required irrigated area (Step 4) Available Irrigated Landscape (Step 1) (Acres) (Acres)
Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Toilet Use Feasibility
Complete the following steps to determine the feasibility of harvesting stormwater runoff for toilet flushing uses on your site:

Step 1: Identify the projected total number of daily toilet users during the wet season, and account for any periodic shut downs or other lapses in occupancy:

Projected Number of Daily Toilet Users: Total
Project Type: Commercial
Step 2: Identify the planned total of all impervious areas on the proposed Project from which runoff might be feasibly captured and stored for toilet use.   Depending on the configuration of buildings and other impervious areas on the site, you may consider the Project site as a whole, or parts of the site, to evaluate reasonable scenarios for capturing and storing runoff and directing the stored runoff to the potential use(s) identified in Step 1 above.

Total Area of Impervious Surfaces: 0 (Acres)
Step 3: Enter the Design Storm depth for the project site (see Exhibit A) into the left column of Table 2‐3 in Chapter 2 to determine the minimum number or toilet users per tributary impervious acre (TUTIA).

Enter your TUTIA factor: TUTIA Factor
Step 4: Multiply the unit value obtained from Step 3 by the total of impervious areas from Step 2 to develop the minimum number of toilet users that would be required.

Minimum number of toilet users: 0
Step 5: Determine if harvesting stormwater runoff for toilet flushing use is feasible for the Project by comparing the Number of Daily Toilet Users (Step 1) to the minimum required number of toilet users (Step 4).

Minimum required Toilet Users (Step 4) Projected number of toilet users (Step 1) 0 (Acres) Number
Other Non‐Potable Use Feasibility
Are there other non‐potable uses for stormwater runoff on the site (e.g. industrial use)? See Chapter 2 of the Guidance for further information.  If yes, describe below. If no, write N/A.

N/A
Step 1: Identify the projected average daily non‐potable demand, in gallons per day, during the Wet Season and accounting for any periodic shut downs or other lapses in occupancy or operation.

Average Daily Demand: Projected Average Daily Use (gpd) Step 2: Identify the planned total of all impervious areas on the proposed Project from which runoff might be feasibly captured and stored for the identified non‐potable use. Depending on the configuration of buildings and other impervious areas on the site, you may consider the Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Project site as a whole, or parts of the site, to evaluate reasonable scenarios for capturing and storing runoff and directing the stored runoff to the potential use(s) identified in Step 1 above.

Total Area of Impervious Surfaces: Insert Area (Acres)
Step 3: Enter the Design Storm Depth for the Project site (see Exhibit A) into the left column of Table 2‐5 in Chapter 2  to determine the minimum demand for non‐potable uses of stormwater runoff per tributary impervious acre.

Enter the factor from Table 2‐3: Enter Value
Step 4: Multiply the unit value obtained from Step 4 by the total of impervious areas from Step 3 to develop the minimum gpd of non‐potable use that would be required.

Minimum required use: Minimum use required (gpd)
Step 5: Determine if harvesting stormwater runoff for other non‐potable use is feasible for the Project by comparing the Number of Daily Toilet Users (Step 1) to the minimum required number of toilet users (Step 4).

Minimum required non‐potable use (Step 4) Projected average daily use (Step 1) Minimum use required (gpd) Projected Average Daily Use (gpd) If Irrigation, Toilet and Other Use feasibility anticipated demands are less than the applicable minimum values, Harvest and Use BMPs are not required and you should proceed to utilize LID Bioretention and Biotreatment BMPs, unless a site‐specific analysis has been completed that demonstrates technical infeasibility as noted in D.3 below.

D.3 Bioretention and Biotreatment Assessment
Other LID Bioretention and Biotreatment BMPs as described in Chapter 2.3 of the WQMP Guidance Document are feasible on nearly all development sites with sufficient advance planning.

Select one of the following:
☒ LID Bioretention/Biotreatment BMPs will be used for some or all DMAs of the Project as noted below in Section D.4
☐ A site‐specific analysis demonstrating the technical infeasibility of all LID BMPs has been performed and is included in Appendix 5. If you plan to submit an analysis demonstrating the technical infeasibility of LID BMPs, request a pre‐submittal meeting with the Copermittee with jurisdiction over the Project site to discuss this option.  Proceed to Section E to document your alternative compliance measures.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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D.4 Other Limiting Geotechnical Conditions
Onsite retention may not be feasible due to specific geotechnical concerns identified in the Geotechnical Report. If any, describe below. If no, write N/A:

N/A.

Table D.2 Geotechnical Concerns for Onsite Retention Table Type of Geotechnical Concern DMAs Feasible (By Name or ID) DMAs Infeasible (By Name or ID) Collapsible Soil
Expansive Soil
Slopes
Liquefaction
Other
D.5 Feasibility Assessment Summaries
From the Infiltration, Harvest and Use, Bioretention and Biotreatment Sections above, complete Table D.3 below to summarize which LID BMPs are technically feasible, and which are not, based upon the established hierarchy.

Table D.3 LID Prioritization Summary Matrix
DMA
Name/ID
LID BMP Hierarchy No LID
(Alternative

1. Infiltration 2. Harvest and use 3. Bioretention 4. Biotreatment Compliance) 1 1a
2 3
3a
4 5
5a
6 Water Quality Management Plan (WQMP)
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For those DMAs where LID BMPs are not feasible, provide a brief narrative below summarizing why they are not feasible, include your technical infeasibility criteria in Appendix 5, and proceed to Section E below to document Alternative Compliance measures for those DMAs. Recall that each proposed DMA must pass through the LID BMP hierarchy before alternative compliance measures may be considered.

Insert narrative description here.

D.6 LID BMP Sizing
Each LID BMP must be designed to ensure that the DCV will be addressed by the selected BMPs. First, calculate the DCV for each LID BMP using the VBMP worksheet in Appendix F of the LID BMP Design Handbook. Second, design the LID BMP to meet the required VBMP using a method approved by the Copermittee with jurisdiction over the Project site. Utilize the worksheets found in the LID BMP Design Handbook or consult with the Copermittee to assist you in correctly sizing your LID BMPs. Complete Table D.4 below to document the DCV and the Proposed Volume for each LID BMP. Provide the completed design procedure sheets for each LID BMP in Appendix 6. You may add additional rows to the table below as needed.

Table D.4 DCV Calculations for LID BMPs
DMA
Type/ID
DMA
(square
feet)
Post‐
Project
Surface
Type
Effective
Impervious
Fraction, If
DMA
Runoff
Factor
DMA
Areas x
Runoff
Factor
Enter BMP Name / Identifier Here
[A] [B] [C] [A] x [C]
1 280,962  Impervious  1 0.89 250,056
Design
Storm
Depth
(in)

DCV, VBMP
(cubic feet)
Proposed
Volume
on Plans
(cubic
feet)
1a 29,185 Basin 0.15 0.14 4,085
2 192,535  Impervious  1 0.89  171,356
3 109,336  Impervious  1 0.89  97,310
3a 40,947 Basin 0.15 0.14 5,733
4 434,730  Impervious  1 0.89  386,910
5 453,460  Impervious  1 0.89  403,580
5a 62,726 Basin 0.15 0.14 8,782
6 90,170    Impervious  1 0.89  80,251
AT =
Σ[A]
1,561,193
Σ= [D]
1,408,063
[E]

0.80 ሾFሿ ൌ ሾDሿxሾEሿ
12 93,870
[G]
196,020
[B], [C] is obtained as described in Section 2.5 of the WQMP Guidance Document [E] is obtained from Exhibit A in the WQMP Guidance Document [G] is obtained from a design procedure sheet, such as in LID BMP Design Handbook and placed in Appendix 6 Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Each LID BMP must be designed to ensure that the Design Capture Volume (DCV) will be addressed by the selected BMPs. First, calculate the Design Capture Volume for each LID BMP using the ‘VBMP’ worksheet in Appendix F of the LID BMP Design Handbook. Second, design the LID BMP to meet the required VBMP using a method approved by the Copermittee. Utilize the worksheets found in the LID BMP Design Handbook or consult with your Copermittee. Complete Table D.5 below to document the Design Capture Volume and the Proposed Volume for each LID BMP. You can add rows to the table as needed. Alternatively, the Santa Margarita Hydrology Model (SMRHM) can be used to size LID BMPs to address the DCV and, if applicable, to size Hydrologic Control BMPs to meet the Hydrologic Performance Standard of the SMR HMP, as identified in Section E.

Table D.5 LID BMP Sizing
BMP Name /
ID
DMA No. BMP Type / Description Design Capture
Volume (ft3)
Proposed Volume
(ft3)
BMP 1 2 Underground
Infiltration/Detention
11,423 20,000
BMP 2 4 Flow Thru Planter 25,794 29,445
BMP 3 6 Flow Thru Planter 5,350 14,663
Section E: Implement Hydrologic Control BMPs and
Sediment Supply BMPs
If a completed Table A.2 demonstrates that the project is exempt from HMP Performance Standards, specify N/A of proceed to Section F, if applicable, and Section G.

E.1 Onsite Feasibility of Hydrologic Control BMPs
An assessment of the feasibility of implementing onsite Hydrologic Control BMPs is required for all projects.

Select one of the following:
 Yes – The implementation of Hydrologic Control BMPs is feasible onsite. (Proceed to Step E.3 and Step E.4)
- Or     ‐
☒No – The project site is larger than one acre and the implementation of Hydrologic Control BMPs is not feasible onsite. (Proceed to Step E.5 and Step F for Alternative Compliance upon approval of the Technical Feasibility Assessment by the Copermittee)  No – The project site is smaller than one acre and the implementation of Hydrologic Control BMPs is not feasible onsite. (Proceed to Step E.2)
If the reasons for infeasibility are different from those listed in Section D.1, describe the technical or spatial reasons that preclude the implementation of onsite Hydrologic Control BMPs. If none, write N/A:

Insert narrative description here.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Approval of the condition for infeasibility, if any, is required by the Copermittee.  Has the condition for infeasibility been approved by the Copermittee?

Y N N/A
E.2 Meeting the HMP Performance Standard for Small Project Sites Select one of the following:
 Yes – The project site is equal to or larger than one acre. (Proceed to Step E.3, Step E.4, and Step E.5)
- Or     ‐
 No – The project site is less than one acre. (Follow the remainder of Step E.2) Only a Simplified Technical Feasibility Study is required from the applicant.   Complete the Simplified Technical Feasibility Study in Appendix 7, which must include, at a minimum, the soil conditions at the PDP, a demonstration of the lack of available space for onsite Hydrologic Control BMPs, an explanation of prohibitive costs to implement Hydrologic Control BMPs, and a written opinion from a Registered Geotechnical Engineer identifying the infeasibility due to geotechnical concerns.

Select one of the following:
 Yes – Onsite Hydrologic Control BMPs are feasible. (Proceed to Step E., Step E.4, and Step E.5) - Or     ‐
 No – Onsite Hydrologic Control BMPs are not feasible per the Simplified Technical Feasibility Study.   (Proceed to Section E.5 for Sediment Supply Performance Standard and Section F for Alternative Compliance)
E.3 Hydrologic Control BMP Selection
Capture of the DCV and achievement of the Hydrologic Performance Standard may be met by combined and/or separate structural BMPs. Similarly, compliance with the two identified requirements may be fully or partially achieved onsite.

For each DMA, identify in Table E.1 if the DCV is fully or partially captured onsite, if the Hydrologic Performance Standard is fully or partially met onsite (by using the SMRHM identified in Step E.4), and if structural BMPs for compliance with the LID requirement and the Hydrologic Performance Standard are combined.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Table E.1 LID & Hydromodification BMP Location
DMA LID BMP Hydrologic Control
BMP
Combined
BMP BMP type and ID
Onsite
Partially Onsite
Offsite
None Required

Onsite
Partially Onsite
Offsite
None Required
Yes
No
Identify the ID and type of Hydrologic Control BMP to
mitigate 1st DMA
Onsite
Partially Onsite
Offsite
None Required
Onsite
Partially Onsite
Offsite
None Required
Yes
No
Identify the ID and type of Hydrologic Control BMP to
mitigate 2nd DMA
Onsite
Partially Onsite
Offsite
None Required
Onsite
Partially Onsite
Offsite
None Required
Yes
No
Identify the ID and type of Hydrologic Control BMP to
mitigate 3rd DMA
For each DMA provide a narrative describing if the DCV and the Hydrologic Performance Standard are to be fully managed onsite. If not, the narrative should detail how and where offsite structural BMPs will achieve management of the DCV and the Hydrologic Performance Standard.

DMA #1 ‐ Insert narrative description here
DMA #2 ‐ Insert narrative description here
DMA #3 ‐ Insert narrative description here
E.4 Hydrologic Control BMP Sizing
Each Hydrologic Control BMP must be designed to ensure that the flow duration curve of the post‐ development DMA will not exceed that of the pre‐existing, naturally occurring, DMA by more than ten percent over a one‐year period. Using SMRHM, the applicant shall demonstrate that the performance of each designed Hydrologic Control BMP complies with the Hydrologic Performance Standard. Complete Table E.2 below and identify, for each DMA, the type of Hydrologic Control BMP, if the SMRHM model confirmed the management (Identified as “passed” in SMRHM), the total volume capacity of the Hydrologic Control BMP, the Hydrologic Control BMP footprint at top floor elevation, and the drawdown time of the Hydrologic Control BMP. SMRHM summary reports should be documented in Appendix 7.

Refer to the SMRHM Guidance Document for additional information on SMRHM. You can add rows to the table as needed.

Table E.2 Hydrologic Control BMP Sizing
BMP
Name / ID
DMA
No.

BMP Type / Description SMRHM
Passed
BMP Volume
(ac‐ft)
BMP
Footprint (ac)
Drawdown
time (hr)

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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E.5 Implement Sediment Supply BMPs
The applicant may refer to Section 2.3 of the SMR HMP for a comprehensive description of the methodology to meet the Sediment Supply Performance Standard. Complete the following steps to determine compliance with the Sediment Supply Performance Standard:

Step 1: Identify if the site is a Significant Source of Bed Sediment Supply to the receiving channel  Step 1.A – Is the Bed Sediment of onsite streams similar to that of receiving streams? Rate the similarity: High
Medium
Low
Results from the geotechnical and sieve analysis to be performed both onsite and in the receiving channel should be documented in Appendix 7. Of particular interest, the results of the sieve analysis, the soil erodibility factor, a description of the topographic relief of the project area, and the lithology of onsite soils should be reported in Appendix 7.  Step 1.B – Are onsite streams capable of delivering Bed Sediment Supply from the site, if any, to the receiving channel?
Rate the potential: High
Medium
Low
Results from the analyses of the sediment delivery potential to the receiving channel should be documented in Appendix 7 and identify, at a minimum, the Sediment Source, the distance to the receiving channel, the onsite channel density, the project watershed area, the slope, length, land use, and rainfall intensity.
 Step 1.C – Will the receiving channel adversely respond to a change in Bed Sediment Load? Rate the need for bed sediment supply:

High
Medium
Low
Results from the in‐stream analysis to be performed both onsite should be documented in Appendix 7.

The analysis should, at a minimum, quantify the bank stability and the degree of incision, provide a Water Quality Management Plan (WQMP)
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gradation of the Bed Sediment within the receiving channel, and identify if the channel is sediment supply‐limited.
 Step 1.D – Summary of Step 1
Summarize in Table E.3 the findings of Step 1 and associate a score (in parenthesis) to each step. The sum of the three individual scores determines if a stream is a significant contributor to the receiving stream.
 Sum is equal to or greater than eight  ‐  Site is a significant source of sediment bed material – all on‐site streams must be preserved or by‐passed within the site plan. The applicant shall proceed to Step 2 for all onsite streams.  Sum is greater than five but lower than eight. Site is a source of sediment bed material – some of the on‐site streams must be preserved (with identified streams noted). The applicant shall proceed to Step 2 for the identified streams only.  Sum is equal to or lower than five. Site is not a significant source of sediment bed material. The applicant may advance to Section F.

Table E.3 Triad Assessment Summary
Step Rating Total Score

1.A High (3) Medium (2) Low (1) 1

1.B High (3) Medium (2) Low (1) 1

1.C High (3) Medium (2) Low (1) 1
Significant Source Rating of Bed Sediment to the receiving channel(s) 3 Step 2: Preservation of Identified Onsite Channels
Onsite streams identified as a Significant Source of Bed Sediment should be avoided in the site design.

Check one of the following:

The site design does avoid all onsite channels identified as a Significant Source of Bed Sediment (The applicant may disregard subsequent steps of Section E.5 and directly advance directly to Section F.) - Or     ‐
The site design does NOT avoid all onsite channels identified as a Significant Source of Bed Sediment (The applicant may proceed with the subsequent steps of Section E.5).

Provide in Appendix 7 a site map that identifies all onsite channels and highlights those onsite channels that were identified as a Significant Source of Bed Sediment. The site map shall demonstrate, if feasible, that the site design avoids those onsite channels identified as a Significant Source of Bed Sediment. In addition, the applicant shall describe the characteristics of each onsite channel identified as a Significant Source of Bed Sediment. If the design plan cannot avoid the onsite channels, please provide a rationale for each channel individually.

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CarMax Automotive Dealership ‐ Murrieta
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Identified Channel #1 ‐ Insert narrative description here Identified Channel #2 ‐ Insert narrative description here Identified Channel #3 ‐ Insert narrative description here Step 3: By‐Pass of Upstream Drainage(s) to Preserve the discharge of Bed Sediment Supply to the receiving channel(s)
Onsite channels identified as a Significant Source of Bed Sediment Supply should be by‐passed the discharge of Bed Sediment Supply to the receiving channel(s).

Check one of the following:

The site design does avoid and/or bypass all onsite channels identified as a source of Bed Sediment Supply (The applicant may directly advance to Section F.) - Or     ‐
The site design does NOT avoid or by‐pass all onsite channels identified as a source of Bed Sediment Supply (The applicant may proceed to an Alternative Approach, as defined in Section F).

Provide in Appendix 7 a site map that identifies all onsite channels and highlights those onsite channels that were identified as a Significant Source of Bed Sediment Supply. The site map shall demonstrate, if feasible, that the site design avoids or by‐passes those onsite channels of significant Bed Sediment Supply to the receiving channel(s). In addition, the applicant shall describe the characteristics of each onsite channel identified as a Significant Source of Bed Sediment Supply. If the design plan cannot avoid or by‐pass the onsite channels, please provide a rationale for each channel individually.

Identified Channel #1 ‐ Insert narrative description here Identified Channel #2 ‐ Insert narrative description here Identified Channel #3 ‐ Insert narrative description here Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Section F: Alternative Compliance
LID BMPs and Hydrologic Control BMPs are expected to be feasible on virtually all projects. Where LID BMPs and/or Hydrologic Control BMPs have been demonstrated to be infeasible as documented in Section D and/or Section E, respectively, other Treatment Control BMPs or alternative compliance approaches must be used (subject LID waiver and/or HMP alternative compliance approval by the Copermittee).

In addition, if supporting documentation demonstrates the infeasibility to implement Sediment Supply BMPs onsite (See Section E.5), the applicant may refer to Section F.5.

Check one of the following boxes:
☒LID Principles, LID BMPs, Hydrologic Control BMPs, and Sediment Supply BMPs have been incorporated into the site design to fully address all Drainage Management Areas. No alternative compliance measures are required for this project and thus this Section is not required to be completed.
- Or    ‐
 LID Principles and LID BMPs have NOT been incorporated into the site design to fully address the LID requirements for all Drainage Management Areas AND HMP Performance Standards are not fully addressed in the following Drainage Management Areas. o The following Drainage Management Areas are unable to be addressed using LID BMPs.

A site specific analysis demonstrating technical infeasibility of LID BMPs has been approved by the Copermittee and included in Appendix 5. The following alternative compliance measures on the following pages are being implemented to ensure that any pollutant loads expected to be discharged by not incorporating LID BMPs, are fully mitigated. The applicant should complete Section F.1, Section F.2, and Section F.3, as applicable.
o A site specific analysis demonstrating technical infeasibility of Hydrologic Control BMPs and Sediment Supply BMPs has been approved by the Copermittee and included in Appendix 7.  Projects less than one acre have completed the Simplified Technical Feasibility Study. The applicant should complete Section F.5 and/or Section F.6, as applicable.

List DMAs Here.
- Or    ‐
 LID Principles and LID BMPs have been incorporated into the site design to fully address the DCV for all Drainage Management Areas. However, HMP Performance Standards are not fully addressed in the following Drainage Management Areas. A site specific analysis demonstrating technical infeasibility of Hydrologic Control BMPs and Sediment Supply BMPs has been approved by the Copermittee and included in Appendix 7.  Projects less than one acre have Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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completed the Simplified Technical Feasibility. The applicant should complete Section F.5 and/or Section F.6, as applicable.

List DMAs Here.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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F.1 Identify Pollutants of Concern
Utilizing Table A.1 from Section A above which noted your project’s Receiving Waters and their associated USEPA approved 303(d) listed impairments, cross reference this information with that of your selected Priority Development Project Category in Table F.1 below. If the identified General Pollutant Categories are the same as those listed for your Receiving Waters, then these will be your Pollutants of Concern and the appropriate box or boxes will be checked on the last row.  The purpose of this is to document compliance and to help you appropriately plan for mitigating your Pollutants of Concern in lieu of implementing LID BMPs.

Table F.1 Potential Pollutants by Land Use Type
Priority Development
Project Categories and/or
Project Features (check those
that apply)
General Pollutant Categories
Bacterial
Indicators Metals Nutrients Pesticides
Toxic
Organic
Compounds
Sediments Trash &
Debris
Oil &
Grease
Detached Residential
Development P N P P N P P P
Attached Residential
Development P N P P N P P P(2)
Commercial/Industrial
Development P(3) P P(1) P(1) P(5) P(1) P P
Automotive Repair
Shops N P N N P(4, 5) N P P
Restaurants
(>5,000 ft2
) P N N N N N P P
Hillside Development
(>5,000 ft2) P N P P N P P P
Parking Lots
(>5,000 ft2
) P(6) P P(1) P(1) P(4) P(1) P P
Retail Gasoline Outlets N P N N P N P P
Project Priority Pollutant(s)
of Concern
P = Potential
N = Not Potential
(1) A potential Pollutant if non-native landscaping exists or is proposed onsite; otherwise not expected (2) A potential Pollutant if the project includes uncovered parking areas; otherwise not expected (3) A potential Pollutant is land use involving animal waste (4) Specifically petroleum hydrocarbons
(5) Specifically solvents
(6) Bacterial indicators are routinely detected in pavement runoff

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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F.2 Stormwater Credits
Projects that cannot implement LID BMPs but nevertheless implement Smart Growth Principles are potentially eligible for Stormwater Credits. Utilize Table 3‐7 within the WQMP Guidance Document to identify your Project Category and its associated Water Quality Credit. If not applicable, write N/A.

Table F.2 Stormwater Credits
Qualifying Project Categories Credit Percentage2

N/A N/A

Total Credit Percentage1
1 Cannot Exceed 50% 2
Obtain corresponding data from Table 3‐7 in the WQMP Guidance  Document F.3 Sizing Criteria
After you appropriately considered Stormwater Credits for your Project, utilize Table F.3 below to appropriately size them to the DCV, or Design Flow Rate, as applicable. Please reference Chapter 3.5.5 of the WQMP Guidance Document for further information.

Table F.3 Treatment Control BMP Sizing
DMA
Type/ID
DMA
(square
feet)
Post‐
Project
Surface
Type
Effective
Impervious
Fraction, If
DMA
Runoff
Factor
DMA x
Runoff
Factor
Enter BMP Name / Identifier Here
[A] [B] [C] [A] x [C]
1 Design
Storm
Depth
(in)
Minimum DCV
or Design Flow
Rate (cubic
feet or cfs)
Total Storm
Water
Credit %
Reduction
Proposed
Volume
or Flow
on Plans
(cubic
feet or
cfs)
2 3
4 5
6 AT =
Σ[A] Σ= [D] [E] ሾFሿ ൌ ሾDሿxሾEሿ
ሾGሿ [F] X (1‐[H]) [I]
[B], [C] is obtained as described in Section 2.5 from the WQMP Guidance Document [E] is obtained from Exhibit A in the WQMP Guidance Document [G] is for Flow‐Based Treatment Control BMPs [G] = 43,560, for Volume‐Based Control Treatment BMPs, [G] = 12 [H] is from the Total Stormwater Credit Percentage as Calculated from Table E.2 above [I] as obtained from a design procedure sheet from the BMP manufacturer and should be included in Appendix 6

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F.4 Treatment Control BMP Selection
Treatment Control BMPs typically provide proprietary treatment mechanisms to treat potential Pollutants in runoff, but do not sustain significant biological processes. Treatment Control BMPs must have a removal efficiency of a medium or high effectiveness as quantified below:
 High: equal to or greater than 80% removal efficiency  Medium: between 40% and 80% removal efficiency
Such removal efficiency documentation (e.g., studies, reports, etc.) as further discussed in Chapter 3.5.2 of the WQMP Guidance Document, must be included in Appendix 6. In addition, ensure that proposed Treatment Control BMPs are properly identified on the WQMP Site Plan in Appendix 1.

Table F.4 Treatment Control BMP Selection
Selected Treatment Control BMP
Name or ID1
Priority Pollutant(s) of
Concern to Mitigate2
Removal Efficiency
Percentage3

1 Treatment Control BMPs must not be constructed within Receiving Waters. In addition, a proposed Treatment Control BMP may be listed more than once if they possess more than one qualifying pollutant removal efficiency. 2 Cross Reference Table E.1 above to populate this column. 3 As documented in a Copermittee Approved Study and provided in Appendix 6.

F.5 Hydrologic Performance Standard – Alternative Compliance Approach
Alternative compliance options are only available if the governing Copermittee has acknowledged the infeasibility of onsite Hydrologic Control BMPs and approved an alternative compliance approach.

Attach to Appendix 7 the Technical Feasibility Study (Projects equal or greater than one acre) or Simplified Technical Feasibility Study (Projects less than one acre) along with a written approval from the Copermittee. The applicant may refer to Section 2.2.iv of the SMR HMP for extensive guidelines on the alternative compliance approach.

Select the pursued alternative and describe the specifics of the alternative:
 Offsite Hydrologic Control Management within the same channel system Insert narrative description here
 In‐Stream Restoration Project
Insert narrative description here
For Offsite Hydrologic Control BMP Option
Each Hydrologic Control BMP must be designed to ensure that the flow duration curve of the post‐ development DMA will not exceed that of the pre‐existing, naturally occurring, DMA by more than ten percent over a one‐year period. Using SMRHM, the applicant shall demonstrate that the performance of Water Quality Management Plan (WQMP)
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each designed Hydrologic Control BMP is equivalent with the Hydrologic Performance Standard for onsite conditions. Complete Table F.4 below and identify, for each Hydrologic Control BMP, the equivalent DMA the Hydrologic Control BMP mitigates, that the SMRHM model passed, the total volume capacity of the BMP, the BMP footprint at top floor elevation, and the drawdown time of the BMP.

SMRHM summary reports for the alternative approach should be documented in Appendix 7. Refer to the SMRHM Guidance Document for additional information on SMRHM. You can add rows to the table as needed.

Table F.5 Offsite Hydrologic Control BMP Sizing
BMP Name / Type Equivalent
DMA (ac)
SMRHM
Passed
BMP Volume
(ac‐ft)
BMP
Footprint (ac)
Drawdown
time (hr)

For Instream Restoration Option
Attach to Appendix 7 the technical report detailing the condition of the receiving channel subject to the proposed hydrologic and sediment regimes. Provide the full design plans for the in‐stream restoration project that have been approved by the Copermittee.

F.6 Sediment Supply Performance Standard ‐ Alternative Compliance The alternative compliance option to the Sediment Supply Performance Standard is only available if the governing Copermittee has approved the investigation of alternative Bed Sediment Supply options.

Attach to Appendix 7 the Technical Feasibility Study, along with the modeling analysis, the long‐term monitoring program, and the potential corrective actions, that demonstrate the performance of the overall alternative compliance program. The applicant may refer to Section 2.3.ii of the SMR HMP for extensive guidelines on the alternative compliance approach.

Provide a narrative describing the alternative Bed Sediment Supply approach, including the long‐term monitoring program and the findings of the numerical modeling.

Insert narrative description here

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Section G: Source Control BMPs
Source Control BMPs include permanent, structural features that may be required in your Project plans — such as roofs over and berms around trash and recycling areas — and Operational BMPs, such as regular sweeping and “housekeeping”, that must be implemented by the site’s occupant or user. The Maximum Extent Practicable (MEP) standard typically requires both types of BMPs.   In general, Operational BMPs cannot be substituted for a feasible and effective structural BMP. Using the Pollutant Sources/Source Control Checklist in Appendix 8, review the following procedure to specify Source Control BMPs for your site:

1. Identify Pollutant Sources: Review Column 1 in the Pollutant Sources/Source Control Checklist.

Check off the potential sources of Pollutants that apply to your site.

2. Note Locations on Project‐Specific WQMP Exhibit: Note the corresponding requirements listed in Column 2 of the Pollutant Sources/Source Control Checklist. Show the location of each Pollutant source and each permanent Source Control BMP in your Project‐Specific WQMP Exhibit located in Appendix 1.

3. Prepare a Table and Narrative: Check off the corresponding requirements listed in Column 3 in the Pollutant Sources/Source Control Checklist. In the left column of Table G.1 below, list each potential source of Pollutants on your site (from those that you checked in the Pollutant Sources/Source Control Checklist). In the middle column, list the corresponding permanent, Structural Source Control BMPs (from Columns 2 and 3 of the Pollutant Sources/Source Control Checklist) used to prevent Pollutants from entering runoff. Add additional narrative in this column that explains any special features, materials or methods of construction that will be used to implement these permanent, Structural Source Control BMPs.

4. Identify Operational Source Control BMPs: To complete your table, refer once again to the Pollutant Sources/Source Control Checklist. List in the right column of your table the Operational BMPs that should be implemented as long as the anticipated activities continue at the site. Copermittee stormwater ordinances require that applicable Source Control BMPs be implemented; the same BMPs may also be required as a condition of a use permit or other revocable Discretionary Approval for use of the site.

Table G.1 Structural and Operational Source Control BMP Potential Sources of Runoff
Pollutants Structural Source Control BMPs
Operational Source Control BMPs
Onsite storm drain inlets Marked “Only Rain Down the
Storm Drain” on all inlet
locations
Maintain periodically, provide
SWPPP, include maintenance
requirements in site owner’s
agreement.

Landscape/Outdoor Pesticide
Use
Preserve existing vegetation,
design landscaping to minimize
irrigation and runoff, use soil
saturation tolerant plans in
retention basin area, use pest
Maintain landscaping using
minimum to no pesticides.

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resistant plants
Plazas, Sidewalks, and Parking
Lots
Sweep plazas, sidewalks, and
parking lots regularly to prevent
accumulation of sediment and
litter.

Section H: Construction Plan Checklist
Populate Table H.1 below to assist the plan checker in an expeditious review of your project. The first two columns will contain information that was prepared in previous steps, while the last column will be populated with the corresponding plan sheets. This table is to be completed with the submittal of your final Project‐Specific WQMP.

Table H.1 Construction Plan Cross‐reference
BMP No. or ID BMP Identifier and Description Corresponding Plan Sheet(s) BMP 1 Underground Infiltration Chambers Storm Drain Plan – Sheet X BMP 2 Flow thru planter Storm Drain Plan – Sheet X
BMP 3 Flow thru planter Storm Drain Plan – Sheet X

Note that the updated table — or Construction Plan WQMP Checklist — is only a reference tool to facilitate an easy comparison of the construction plans to your Project‐Specific WQMP.  The Copermittee with jurisdiction over the Project site can advise you regarding the process required to propose changes to the approved Project‐Specific WQMP.

Water Quality Management Plan (WQMP)
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Section I: Operation, Maintenance and Funding
The Copermittee with jurisdiction over the Project site will periodically verify that BMPs on your Project are maintained and continue to operate as designed. To make this possible, the Copermittee will require that you include in Appendix 9 of this Project‐Specific WQMP:

1. A means to finance and implement maintenance of BMPs in perpetuity, including replacement cost.

2. Acceptance of responsibility for maintenance from the time the BMPs are constructed until responsibility for operation and maintenance is legally transferred. A warranty covering a period following construction may also be required.

3. An outline of general maintenance requirements for the Stormwater BMPs you have selected.

4. Figures delineating and designating pervious and impervious areas, location, and type of Stormwater BMP, and tables of pervious and impervious areas served by each facility. Geo‐ locating the BMPs using a coordinate system of latitude and longitude is recommended to help facilitate a future statewide database system.

5. A separate list and location of self‐retaining areas or areas addressed by LID Principles that do not require specialized Operations and Maintenance or inspections but will require typical landscape maintenance as noted in Chapter 5, in the WQMP Guidance. Include a brief description of typical landscape maintenance for these areas.

The Copermittee with jurisdiction over the Project site will also require that you prepare and submit a detailed BMP Operation and Maintenance Plan that sets forth a maintenance schedule for each of the BMPs built on your site. An agreement assigning responsibility for maintenance and providing for inspections and certification may also be required.

Details of these requirements and instructions for preparing a BMP Operation and Maintenance Plan are in Chapter 5 of the WQMP Guidance Document.

Maintenance Mechanism: Insert text here.

Will the proposed BMPs be maintained by a Homeowners’ Association (HOA) or Property Owners Association (POA)?
Y N
Include your Operation and Maintenance Plan and Maintenance Mechanism in Appendix 9. Additionally, include all pertinent forms of educational materials for those personnel that will be maintaining the proposed BMPs within this Project‐Specific WQMP in Appendix 10.

Water Quality Management Plan (WQMP)
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Acronyms, Abbreviations and Definitions
2010 SMR MS4
Permit
Order No. R9-2010-0016, an NPDES Permit issued by the San Diego Regional Water Quality Control Board.

Applicant Public or private entity seeking the discretionary approval of new or replaced improvements from the Copermittee with jurisdiction over the project site. The Applicant has overall responsibility for the implementation and the approval of a Priority Development Project. The WQMP uses consistently the term “user” to refer to the applicant such as developer or project proponent.

The WQMP employs also the designation “user” to identify the Registered Professional Civil Engineer responsible for submitting the Project-Specific WQMP, and designing the required BMPs.

Best Management
Practice (BMP)
Defined in 40 CFR 122.2 as schedules of activities, prohibitions of practices, maintenance procedures, and other management practices to prevent or reduce the pollution of waters of the United States. BMPs also include treatment requirements, operating procedures and practices to control plant site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw material storage. In the case of municipal storm water permits, BMPs are typically used in place of numeric effluent limits.

BMP Fact Sheets BMP Fact Sheets are available in the LID BMP Design Handbook.

Individual BMP Fact Sheets include sitting considerations, and design and sizing guidelines for seven types of structural BMPs (infiltration basin, infiltration trench, permeable pavement, harvestand-use, bioretention, extended detention basin, and sand filter).

California
Stormwater Quality
Association (CASQA)
Publisher of the California Stormwater Best Management Practices Handbooks, available at
www.cabmphandbooks.com.

Conventional
Treatment Control
BMP
A type of BMP that provides treatment of stormwater runoff.

Conventional treatment control BMPs, while designed to treat particular Pollutants, typically do not provide the same level of volume reduction as LID BMPs, and commonly require more specialized maintenance than LID BMPs. As such, the 2010 SMR MS4 Permit and this WQMP require the use of LID BMPs wherever feasible, before Conventional Treatment BMPs can be considered or implemented.

Copermittees The 2010 SMR MS4 Permit identifies the Cities of Murrieta, Temecula, and Wildomar, the County, and the District, as Copermittees for the SMR.

County The abbreviation refers to the County of Riverside in this document.

CEQA California Environmental Quality Act - a statute that requires state and local agencies to identify the significant environmental impacts of their actions and to avoid or mitigate those impacts, if feasible.

Water Quality Management Plan (WQMP)
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CIMIS California Irrigation Management Information System - an integrated network of 118 automated active weather stations all over California managed by the California Department of Water Resources.

CWA Clean Water Act - is the primary federal law governing water pollution. Passed in 1972, the CWA established the goals of eliminating releases of high amounts of toxic substances into water, eliminating additional water pollution by 1985, and ensuring that surface waters would meet standards necessary for human sports and recreation by 1983.

CWA Section 402(p) is the federal statute requiring NPDES permits for discharges from MS4s.

CWA Section 303(d)
Waterbody
Impaired water in which water quality does not meet applicable water quality standards and/or is not expected to meet water quality standards, even after the application of technology based pollution controls required by the CWA. The discharge of urban runoff to these water bodies by the Copermittees is significant because these discharges can cause or contribute to violations of applicable water quality standards.

Design Storm The 2010 SMR MS4 Permit has established the 85th percentile, 24- hour storm event as the "Design Storm". The applicant may refer to Exhibit A to identify the applicable Design Storm Depth (D85) to the project.

DCV Design Capture Volume (DCV) is the volume of runoff produced from the Design Storm to be mitigated through LID Retention BMPs, Other LID BMPs and Volume Based Conventional
Treatment BMPs, as appropriate.

Design Flow Rate The design flow rate represents the minimum flow rate capacity that flow-based conventional treatment control BMPs should treat to the MEP, when considered.

DCIA Directly Connected Impervious Areas - those impervious areas that are hydraulically connected to the MS4 (i.e. street curbs, catch basins, storm drains, etc.) and thence to the structural BMP without flowing over pervious areas.

Discretionary
Approval
A decision in which a Copermittee uses its judgment in deciding whether and how to carry out or approve a project.

District Riverside County Flood Control and Water Conservation District.

DMA A Drainage Management Area - a delineated portion of a project site that is hydraulically connected to a common structural BMP or conveyance point. The Applicant may refer to Section 3.3 for further guidelines on how to delineate DMAs.

Water Quality Management Plan (WQMP)
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Drawdown Time Refers to the amount of time the design volume takes to pass through the BMP. The specified or incorporated drawdown times are to ensure that adequate contact or detention time has occurred for treatment, while not creating vector or other nuisance issues. It is important to abide by the drawdown time requirements stated in the fact sheet for each specific BMP.

Effective Area Area which 1) is suitable for a BMP (for example, if infiltration is potentially feasible for the site based on infeasibility criteria, infiltration must be allowed over this area) and 2) receives runoff from impervious areas.

ESA An Environmental Sensitive Area (ESA) designates an area "in which plants or animals life or their habitats are either rare or especially valuable because of their special nature or role in an ecosystem and which would be easily disturbed or degraded by human activities and developments". (Reference: California Public Resources Code § 30107.5).

ET Evapotranspiration (ET) is the loss of water to the atmosphere by the combined processes of evaporation (from soil and plant surfaces) and transpiration (from plant tissues). It is also an indicator of how much water crops, lawn, garden, and trees need for healthy growth and productivity
FAR The Floor Area Ratio (FAR) is the total square feet of a building divided by the total square feet of the lot the building is located on.

Flow-Based BMP Flow-based BMPs are conventional treatment control BMPs that are sized to treat the design flow rate.

FPPP Facility Pollution Prevention Plan
HCOC Hydrologic Condition of Concern - Exists when the alteration of a site’s hydrologic regime caused by development would cause significant impacts on downstream channels and aquatic habitats, alone or in conjunction with impacts of other projects.

HMP Hydromodification Management Plan – Plan defining Performance Standards for PDPs to manage increases in runoff discharge rates and durations.

Hydrologic Control
BMP
BMP to mitigate the increases in runoff discharge rates and durations and meet the Performance Standards set forth in the HMP.

HSG Hydrologic Soil Groups – soil classification to indicate the minimum rate of infiltration obtained for bare soil after prolonged wetting. The HSGs are A (very low runoff potential/high infiltration rate), B, C, and D (high runoff potential/very low infiltration rate)
Hydromodification The 2010 SMR MS4 Permit identifies that increased volume, velocity, frequency and discharge duration of storm water runoff from developed areas has the potential to greatly accelerate downstream erosion, impair stream habitat in natural drainages, and negatively impact beneficial uses.

Water Quality Management Plan (WQMP)
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JRMP A separate Jurisdictional Runoff Management Plan (JRMP) has been developed by each Copermittee and identifies the local programs and activities that the Copermittee is implementing to meet the 2010 SMR MS4 Permit requirements.

LID Low Impact Development (LID) is a site design strategy with a goal of maintaining or replicating the pre-development hydrologic regime through the use of design techniques. LID site design BMPs help preserve and restore the natural hydrologic cycle of the site, allowing for filtration and infiltration which can greatly reduce the volume, peak flow rate, velocity, and pollutant loads of storm water runoff.

LID BMP A type of stormwater BMP that is based upon Low Impact Development concepts. LID BMPs not only provide highly effective treatment of stormwater runoff, but also yield potentially significant reductions in runoff volume – helping to mimic the preproject hydrologic regime, and also require less ongoing maintenance than Treatment Control BMPs. The applicant may refer to Chapter 2.

LID BMP Design
Handbook
The LID BMP Design Handbook was developed by the
Copermittees to provide guidance for the planning, design and maintenance of LID BMPs which may be used to mitigate the water quality impacts of PDPs within the County.

LID Bioretention BMP LID Bioretention BMPs are bioretention areas are vegetated (i.e., landscaped) shallow depressions that provide storage, infiltration, and evapotranspiration, and provide for pollutant removal (e.g., filtration, adsorption, nutrient uptake) by filtering stormwater through the vegetation and soils. In bioretention areas, pore spaces and organic material in the soils help to retain water in the form of soil moisture and to promote the adsorption of pollutants (e.g., dissolved metals and petroleum hydrocarbons) into the soil matrix.

Plants use soil moisture and promote the drying of the soil through transpiration.

The 2010 SMR MS4 Permit defines “retain” as to keep or hold in a particular place, condition, or position without discharge to surface waters.

LID Biotreatment
BMP
BMPs that reduce stormwater pollutant discharges by intercepting rainfall on vegetative canopy, and through incidental infiltration and/or evapotranspiration, and filtration, and other biological and chemical processes. As stormwater passes down through the planting soil, pollutants are filtered, adsorbed, biodegraded, and sequestered by the soil and plants, and collected through an underdrain.

LID Harvest and
Reuse BMP
BMPs used to facilitate capturing Stormwater Runoff for later use without negatively impacting downstream water rights or other Beneficial Uses.

Water Quality Management Plan (WQMP)
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LID Infiltration BMP BMPs to reduce stormwater runoff by capturing and infiltrating the runoff into in-situ soils or amended onsite soils. Typical LID Infiltration BMPs include infiltration basins, infiltration trenches and pervious pavements.

LID Retention BMP BMPs to ensure full onsite retention without runoff of the DCV such as infiltration basins, bioretention, chambers, trenches, permeable pavement and pavers, harvest and reuse.

LID Principles Site design concepts that prevent or minimize the causes (or drivers) of post-construction impacts, and help mimic the predevelopment hydrologic regime.

MEP Maximum Extent Practicable - standard established by the 1987 amendments to the CWA for the reduction of Pollutant discharges from MS4s. Refer to Attachment C of the 2010 SMR MS4 Permit for a complete definition of MEP.

MF Multi-family – zoning classification for parcels having 2 or more living residential units.

MS4 Municipal Separate Storm Sewer System (MS4) is a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains): (i) Owned or operated by a State, city, town, borough, county, parish, district, association, or other public body (created by or pursuant to State law) having jurisdiction over disposal of sewage, industrial wastes, storm water, or other wastes, including special districts under State law such as a sewer district, flood control district or drainage district, or similar entity, or an Indian tribe or an authorized Indian tribal organization, or designated and approved management agency under section 208 of the CWA that discharges to waters of the United States; (ii) Designated or used for collecting or conveying storm water; (iii) Which is not a combined sewer; (iv) Which is not part of the Publicly Owned Treatment Works (POTW) as defined at 40 CFR 122.26.

New Development
Project
Defined by the 2010 MS4 permit as 'Priority Development Projects' if the project, or a component of the project meets the categories and thresholds described in Section 1.1.1.

NPDES National Pollution Discharge Elimination System - Federal program for issuing, modifying, revoking and reissuing, terminating, monitoring and enforcing permits, and imposing and enforcing pretreatment requirements, under Sections 307, 318, 402, and 405 of the CWA.

NRCS Natural Resources Conservation Service
PDP Priority Development Project - Includes New Development and Redevelopment project categories listed in Section F.1.d(2) of Order No. R9-2009-0002.

Water Quality Management Plan (WQMP)
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Priority Pollutants of
Concern
Pollutants expected to be present on the project site and for which a downstream water body is also listed as Impaired under the CWA Section 303(d) list or by a TMDL.

Project-Specific
WQMP
A plan specifying and documenting permanent LID Principles and Stormwater BMPs to control post-construction Pollutants and stormwater runoff for the life of the PDP, and the plans for operation and maintenance of those BMPs for the life of the project.

Receiving Waters Waters of the United States.

Redevelopment
Project
The creation, addition, and or replacement of impervious surface on an already developed site. Examples include the expansion of a building footprint, road widening, the addition to or replacement of a structure, and creation or addition of impervious surfaces.

Replacement of impervious surfaces includes any activity that is not part of a routine maintenance activity where impervious material(s) are removed, exposing underlying soil during construction. Redevelopment does not include trenching and resurfacing associated with utility work; resurfacing existing roadways; new sidewalk construction, pedestrian ramps, or bike lane on existing roads; and routine replacement of damaged pavement, such as pothole repair.

Project that meets the criteria described in Section 1.

Runoff Fund Runoff Funds have not been established by the Copermittees and are not available to the Applicant.

If established, a Runoff Fund will develop regional mitigation projects where PDPs will be able to buy mitigation credits if it is determined that implementing onsite controls is infeasible.

San Diego Regional
Board
San Diego Regional Water Quality Control Board - The term "Regional Board", as defined in Water Code section 13050(b), is intended to refer to the California Regional Water Quality Control Board for the San Diego Region as specified in Water Code Section 13200. State agency responsible for managing and regulating water quality in the SMR.

SCCWRP Southern California Coastal Water Research Project Site Design BMP Site design BMPs prevent or minimize the causes (or drivers) of post-construction impacts, and help mimic the pre-development hydrologic regime.

SF Parcels with a zoning classification for a single residential unit.

SMC Southern California Stormwater Monitoring Coalition SMR The Santa Margarita Region (SMR) represents the portion of the Santa Margarita Watershed that is included within the County of Riverside.

Water Quality Management Plan (WQMP)
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Source Control BMP Source Control BMPs land use or site planning practices, or structural or nonstructural measures that aim to prevent runoff pollution by reducing the potential for contamination at the source of pollution. Source control BMPs minimize the contact between Pollutants and runoff.

Stormwater Credit Stormwater Credit can be claimed by an Applicant if certain development practices that provide broad-scale environmental benefits to communities are incorporated into the project design.

Refer to Section 3.5.4 for additional information on Stormwater Credits.

Structural BMP Structures designed to remove pollutants from stormwater runoff and mitigate hydromodification impacts.

SWPPP Storm Water Pollution Prevention Plan
Tentative Tract Map Tentative Tract Maps are required for all subdivision creating five (5) or more parcels, five (5) or more condominiums as defined in Section 783 of the California Civil Code, a community apartment project containing five (5) or more parcels, or for the conversion of a dwelling to a stock cooperative containing five (5) or more dwelling units.

TMDL Total Maximum Daily Load - the maximum amount of a Pollutant that can be discharged into a waterbody from all sources (point and non-point) and still maintain Water Quality Standards. Under CWA Section 303(d), TMDLs must be developed for all
waterbodies that do not meet Water Quality Standards after application of technology-based controls.

USEPA United States Environmental Protection Agency
Volume-Based BMP Volume-Based BMPs applies to BMPs where the primary mode of pollutant removal depends upon the volumetric capacity such as detention, retention, and infiltration systems.

WQMP Water Quality Management Plan
Wet Season The 2010 SMR MS4 Permit defines the wet season from October 1 through April 30.

Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Appendix 1: Maps and Site Plans
Location Map, WQMP Site Plan and Receiving Waters Map
1 VICINITY MAP
Drawing Name: S:\150015\Eng\150015-0000\Hm\Hydrology Report\Appendix A - Vicinity Map\Figure 1.dwg Last Opened: Jan 27, 2015 - 9:49am by: SRazon

EXHIBIT
CARMAX #6002

MURRIETA, CALIFORNIA NOT TO SCALE

CITY OF MURRIETA

DEVELOPED CONDITIONS

WQMP EXHIBIT
AREA D
CARWASH 936 SF
"S" SERVICE
6,150 SF
S(2) SALES
10,564 SF

PRESENTATION
2,118 SF

CUSTOMER/

EMPLOYEE

PARKING

6.50 ACRES
715 SPACES
SALES

3.10 ACRES
504 SPACES
FUTURE

CARWASH
936 SF
OUTLOT 1

1.06 ACRES
OUTLOT 3

2.19 ACRES
OUTLOT 4

2.19 ACRES
OUTLOT 5

1.62 ACRES
OUTLOT 2

1.06 ACRES
DMA 1
DMA 2
DMA 4
DMA 3
DMA 6
DMA 5
DMA 1a
DMA 3a
DMA 5a
1 | 3
Site Map of Impaired Water:

PROJECT SITE
2 | 3

PROJECT SITE
3 | 3

PROJECT SITE
Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Appendix 2:  Construction Plans
Grading and Drainage Plans

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

CENTERPOINT INTEGRATED SOLUTIONS
PROPOSED CARMAX AUTOMOTIVE DEALERSHIP (STORE #6002)

MURRIETA, CALIFORNIA

TITLE SHEET

VICINITY MAP

PROJECT
SITE
10 14
9 23 13
52 52
50 5
38 33
17 22
28 12
34 63
61 29
9 33
98 12
53 100

CARWASH
936 SF
17 "S" SERVICE
6,150 SF S(2) SALES
10,564 SF

PRESENTATION
2,118 SF
42 38

CUSTOMER/ EMPLOYEE

PARKING

6.50 ACRES
721 SPACES
SALES

3.10 ACRES
504 SPACES
42 42
42 42
42 42

FUTURE CARWASH
936 SF
SALEABLE LOT 1

1.06 ACRES
SALEABLE LOT 2

2.19 ACRES
SALEABLE LOT 3

2.19 ACRES
SALEABLE LOT 4

1.62 ACRES

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

SITE PLAN

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

PRELIMINARY SITE GRADING

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

PRELIMINARY SITE GRADING

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

PRELIMINARY SITE GRADING

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

PRELIMINARY SITE GRADING

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

PRECISE GRADING - PAVING PLAN

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

DETAIL SHEET

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

CROSS SECTIONS AND DETAILS

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

PRELIMINARY STORM DRAIN PLAN

CENTERPOINT INTEGRATED SOLUTIONS

CARMAX AUTO SUPERSTORE - MURRIETA

COMPOSITE UTILITY PLAN
Water Quality Management Plan (WQMP)
CarMax Automotive Dealership ‐ Murrieta
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Appendix 3:  Soils Information
Geotechnical Study and Other Infiltration Testing Data

T R A N S M I T T A L
To: CenterPoint Integrated Solutions, LLC October 3, 2014 1240 Bergen Parkway, Suite A-250
Evergreen, Colorado 80439 Project No: 10791.002
Attention: Mr. Heath Kennedy
Transmitted: The Following: For:

X Mail/Overnight X Draft Report X Your Use
Courier Final Report As Requested
Pick Up Extra Report
Proposal
Other
Subject: Geotechnical Exploration Report, Proposed CarMax Automotive Dealership, Murrieta, California
LEIGHTON CONSULTING, INC.

By: Robert F. Riha / Simon I. Saiid
Distribution: (1) Addressee (plus one PDF copy on CD)

GEOTECHNICAL EXPLORATION REPORT

PROPOSED CARMAX AUTOMOTIVE DEALERSHIP

MURRIETA, CALIFORNIA
Prepared for

CENTERPOINT INTEGRATED SOLUTIONS, LLC
1240 Bergen Parkway, Suite A-250
Evergreen, Colorado 80439
Project No. 10791.002
October 3, 2014
October 3, 2014
Project No. 10791.002
CenterPoint Integrated Solutions, LLC
1240 Bergen Parkway, Suite A-250
Evergreen, Colorado 80439
Attention: Mr. Heath Kennedy
Subject: Geotechnical Exploration Report
Proposed CarMax Automotive Dealership
NWC of Madison Avenue and Guava Street
Murrieta, California
In accordance with your request, we have performed a geotechnical exploration for the subject site northwest of the intersection of Madison Avenue and Guava Street (south of existing Wal-Mart) in the City of Murrieta, California (see Figure 1). This report summarizes our geotechnical findings and provides our preliminary recommendations for the design and construction of the proposed improvements. Based on the results of our exploration, it is our opinion that the site is suitable for the intended use provided the recommendations included in this report are implemented during design and construction phases of development.

If you have any questions regarding this report, please do not hesitate to contact the undersigned. We appreciate this opportunity to be of service on this project.

Respectfully submitted,
LEIGHTON CONSULTING, INC.

Simon I. Saiid
GE 2641 (Exp. 09/30/15)
Principal Engineer
Robert F. Riha
CEG 1921 (Exp. 02/29/16)
Senior Principal Geologist
Distribution: (1) Addressee (plus one PDF copy on CD)
Geotechnical Exploration Report 10791.002
Proposed CarMax Automotive Dealership October 3, 2014
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T A B L E O F C O N T E N T S
Section Page

1.0 I N T R O D U C T I O N ............................................................................................. 1

1.1 Purpose and Scope .............................................................................................1

1.2 Site Description ...................................................................................................1

1.3 Project Description ..............................................................................................2

2.0 F I E L D E X P L O R A T I O N AN D L A B O R A T O R Y T E S T I N G ............... 3

2.1 Field Exploration ..................................................................................................3

2.2 Laboratory Testing ..............................................................................................3

3.0 G E O T E C H N I C AL AN D G E O L O G I C F I N D I N G S ................................ 4

3.1 Regional Geology ................................................................................................4

3.2 Site Specific Geology ..........................................................................................4

3.2.1 Earth Materials ...................................................................................................4

3.3 Groundwater and Surface Water ........................................................................5

3.4 Regional Faulting and Fault Activity ....................................................................5

3.5 Ground Shaking and Seismic Coefficients Per 2013 CBC ................................. 6

3.6 Secondary Seismic Hazards ...............................................................................7

3.6.1 Dynamic Settlement (Liquefaction and/or Dry Settlement) .................................7

3.6.2 Ground Rupture ..................................................................................................7

3.6.3 Rock Falls ...........................................................................................................7

3.6.4 Seiches, Tsunamis, Inundation Due to Large Water Storage Facilities .............7

3.6.5 Slope Stability and Landslides ............................................................................7

3.6.6 Subsidence .........................................................................................................8

3.7 Preliminary Percolation/Infiltration Rates ............................................................8

4.0 C O N C L U S I O N S A N D R E C O M M E N D AT I O N S .................................... 9

4.1 General ................................................................................................................9

4.2 Earthwork ............................................................................................................9

4.2.1 Remedial Grading ..............................................................................................9

4.2.2 Cut/Fill Transition Building Pads .......................................................................10

4.2.3 Structural Fills ...................................................................................................10

4.2.4 Slope Construction ...........................................................................................11

4.2.5 Import Soils .......................................................................................................11

4.2.6 Utility Trenches .................................................................................................12

4.2.7 Temporary Slope Stability ................................................................................13

4.2.8 Shrinkage .........................................................................................................13

4.2.9 Drainage ...........................................................................................................13

4.3 Foundation Design ............................................................................................13

4.3.1 Design Parameters – Spread/Continuous Shallow Footings............................13

4.3.2 Design Parameters – Light Poles .....................................................................14

4.3.3 Interior Slab Design ..........................................................................................15

4.3.4 Settlement Estimates ........................................................................................15 Geotechnical Exploration Report 10791.002
Proposed CarMax Automotive Dealership October 3, 2014
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4.4 Footing Setback ................................................................................................16

4.5 Retaining Walls ................................................................................................. 16

4.6 Sulfate Attack ....................................................................................................17

4.7 Preliminary Pavement Design ...........................................................................17

5.0 G E O T E C H N I C AL C O N S T R U C T I O N S E R V I C E S ............................ 20

6.0 L I M I T AT I O N S ................................................................................................ 21 R E F E R E N C E S ........................................................................................................ 22 Accompanying Tables, Figures, Plates and Appendices
List of Tables
TABLE 1. 2013 CBC SEISMIC COEFFICIENTS PER USGS GENERAL PROCEDURE .......... 6 TABLE 2. SUMMARY OF PERCOLATION/INFILTRATION TESTING ...................................... 8 TABLE 3. RETAINING WALL DESIGN EARTH PRESSURES (STATIC, DRAINED) ...............16 TABLE 4. ASPHALT PAVEMENT SECTIONS .........................................................................18 Figures and Plates (end of text)
Figure 1 – Site Location Map
Figure 2 – Regional Geology Map
Figure 3 – Liquefaction Hazard Map
Figure 4 – Fault Hazard Map
Plate 1 – Geotechnical and Boring Location Plan
Appendices
Appendix A – Logs of Geotechnical Borings
Appendix B – Geotechnical Laboratory Testing
Appendix C – 2013 CBC Seismic Parameters and Pavement Design Calculations Appendix D – Earthwork and Grading Specifications
Appendix E – ASFE - Important Information About Your Geotechnical Report Geotechnical Exploration Report 10791.002
Proposed CarMax Automotive Dealership October 3, 2014
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1.0 I N T R O D U C T I O N

1.1 Purpose and Scope
This geotechnical exploration is for the proposed CarMax automotive dealership located in the City of Murrieta, California (see Figure 1, Site Location Map). Our scope of services for this exploration included the following:
 Review of available site-specific geologic information and provided site plan.  A site reconnaissance and excavation of 40 exploratory borings.

Approximate locations of these borings are depicted on Plate 1. The logs of borings are presented in Appendix A.
 Geotechnical laboratory testing of selected soil samples collected during this exploration. Test results are presented in Appendix B.
 Percolation testing at four locations potentially proposed for water quality basin sites.
 Geotechnical engineering analyses performed or as directed by a California registered Geotechnical Engineer (GE) and reviewed by a California Certified Engineering Geologist (CEG).
 Preparation of this report which presents our geotechnical conclusions and recommendations regarding the grading and design of the proposed structures.

This report is not intended to be used as an environmental assessment (Phase I or other), or foundation/grading plan review.

1.2 Site Description
As depicted on Figure 1, the site of the proposed new CarMax automotive dealership is generally located between Madison Avenue and Interstate 15, and between the existing Wal-Mart and Guava Street, in the City of Murrieta, California.

The site is approximately 40 acres in size and predominantly undeveloped vacant land with the exception of an existing occupied mobile home, and a concrete foundation located on the southwestern corner of the site. An open storm water channel is located in the middle of the site and transects the property in east-west direction. This channel was constructed recently by the City if Murrieta as a part of the overall improvement plan for Line D and D-1 master drainage facility. A set of Geotechnical Exploration Report 10791.002
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southeasterly trending power lines are located on the site near the northeasterly boundary.

The overall site topography gently slopes in a southerly direction toward Madison Avenue. Site vegetation generally consists of annual weeds and grasses with various trees around and along the existing residence along the eastern boundary.

1.3 Project Description
We understand that the proposed site development will consist of the construction of 2 main buildings, 2 to 3 smaller auxiliary buildings, underground fuel storage and large parking lots. The proposed one-story buildings are expected to consist of masonry block or concrete tilt-up wall panels and metal roofing with typical structural loads. A masonry site wall is proposed to surround portions of the site and may be up to 6 feet in height. Site grading is expected to be minimal (cut/fill <20 feet) plus remedial grading, where applicable. Cut or fill slopes are expected to be constructed at 2:1 (horizontal to vertical) inclinations.

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2.0 F I E L D E X P L O R A T I O N AN D L A B O R A T O R Y T E S T I N G

2.1 Field Exploration
Our field exploration consisted of the excavation of forty (40) borings within the site at locations agreed to by the civil engineer/client. Some borings were strategically located to explore subsurface conditions at proposed buildings locations and parking areas to provide basis for grading recommendations as well as foundation and pavement design. During exploration, in-situ undisturbed (Cal Ring) and disturbed/bulk samples were collected from the borings for further laboratory testing and evaluation. Approximate locations of these exploratory borings are depicted on the Boring Location Plan (Plate 1). Sampling was conducted by a staff geologist from our firm. After logging and sampling, the excavations were loosely backfilled with spoils generated during excavation. The exploration logs from this exploration investigation are included in Appendix A.

2.2 Laboratory Testing
Laboratory tests were performed on representative bulk samples to provide a basis for development of remedial earthwork and geotechnical design parameters. The laboratory testing program included maximum dry density and optimum moisture curve, expansion index, in-situ moisture and density, R-value, direct shear and soluble sulfate content. The results of our laboratory testing from this exploration are presented in Appendix B.

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3.0 G E O T E C H N I C AL AN D G E O L O G I C F I N D I N G S

3.1 Regional Geology
The site is located within a prominent natural geomorphic province in southwestern California known as the Peninsular Ranges. This province is characterized by steep, elongated ranges and valleys that trend northwestward. More specifically, the site is located within the southwestern portion of the relatively stable Perris Block, adjacent to the Elsinore Trough (Kennedy, 1977).

The Perris Block, approximately 20 miles by 50 miles in extent, is bounded by the San Jacinto Fault Zone to the northwest, the Elsinore Fault Zone to the southwest, the Cucamonga Fault Zone to the northwest, and the Temecula Basin to the southeast. The Perris Block has had a complex tectonic history, apparently undergoing relative vertical land-movements of several thousand feet in response to movement on the Elsinore and San Jacinto Fault Zones. Thin sedimentary and volcanic materials locally mantle crystalline bedrock. Alluvial fan deposits fill the lower valley areas, as mapped regionally on Figure 2, Regional Geology Map.

3.2 Site Specific Geology

3.2.1 Earth Materials
Our field exploration, observations, and review of the pertinent literature indicate that the site is underlain by a Pleistocene-age coarse-grained formation (locally known as Pauba Formation). Shallow alluvial deposits were encountered in natural drainage courses. A relatively thin layer to artificial fill was noted in localized areas of the site. These units are discussed in the following sections in order of increasing age. A more detailed description of each unit is provided on the logs of borings in Appendix A.
 Artificial Fill (mapped as Afu): Artificial fill soils were locally observed within various areas of the site and generally expected to extend from

2.5 to 5 feet below ground surface (BGS). Most fill was encountered within the parcel in the easterly portion of the site. This parcel/existing residence required cut and fill grading to achieve existing pad. Localized artificial fill may also be encountered in the vicinity of other previously constructed residences, underground utilities and septic tank systems.

Artificial fill is also associated with the storm drain system crossing the property and was compacted during construction. However, documentation of the compaction of this buried pipeline backfill was not Geotechnical Exploration Report 10791.002
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available at the time of this report preparation. As encountered in our borings, artificial fill soils appear to be silty sand (SM) likely derived from onsite sources. Based on the results of our laboratory testing, these materials are expected to possess very low expansion potential (EI<21).  Young Alluvial Deposits (mapped as Qal): Young alluvial deposits were encountered in several borings in local drainages to depths ranging from 2.5 to 5 feet BGS and mantling the Pauba Formation bedrock. As encountered, younger alluvium generally appear to be loose (at the surface) to medium dense, silty sand (SM) with trace gravel. Based on the results of our laboratory testing, these materials are expected to possess very low expansion potential (0<EI<21).
 Pauba Formation (mapped as Qps or Qss): The Pauba Formation bedrock materials were encountered in all of our borings below the artificial fill and younger alluvial materials. These materials generally consist of medium-dense to very dense, silty sands (SM) with interbedded silt with sand (ML), clayey sand (SC) and poorly- to wellgraded sand (SP/SW) with some gravel. Sandy clay (CL) layers were locally encountered (LB-21). Based on the results of our laboratory testing, these materials appear to have a very slight collapse potential (<1%) and generally possess very low expansion potential (0<EI<21).

However, some interbedded silt and clay layers may possess medium to high expansion potential (51<EI<121).

3.3 Groundwater and Surface Water
Groundwater was locally encountered during this exploration at a depth of approximately 48.3 feet BGS in boring LB-13 (EL.~1045). This boring was located within a local drainage swale in the central portion of the site (see Plate 1). All other shallower borings did not encounter ground water. The Department of Water Resource data for two local wells (Well 07S03W21K002S & 07S03W15N002S) indicate a groundwater elevation to be approximately elevation 1035, or on the order of 50 to 80 feet below site ground elevations. However, it should be noted that local perched water conditions may occur in the future, and may fluctuate seasonally, depending on rainfall conditions. Seasonal surface water should be expected within the onsite drainage culvert/channel.

3.4 Regional Faulting and Fault Activity
The subject site, like the rest of Southern California, is located within a seismically active region as a result of being located near the active margin between the North Geotechnical Exploration Report 10791.002
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American and Pacific tectonic plates. The principal source of seismic activity is movement along the northwest-trending regional fault systems such as the San Andreas, San Jacinto, and Elsinore Fault Zones. Based on published geologic hazard maps, this proposed building is not located within a currently designated Alquist-Priolo (AP) Earthquake Fault Zone. However, a County of Riverside Fault Zone is located along the northwest property boundary, beyond the limits of any proposed building construction (see Figure 4).

3.5 Ground Shaking and Seismic Coefficients Per 2013 CBC Strong ground shaking can be expected at the site during moderate to severe earthquakes in this general region. This is common to virtually all of Southern California. Intensity of ground shaking at a given location depends primarily upon earthquake magnitude, site distance from the source, and site response (soil type) characteristics. The site-specific seismic coefficients provided in this section are based on an interactive tool/program currently available on USGS website. Based on ASCE 7-10 as the Design Code Reference Document and site Class D, the seismic coefficients for this site are as listed in the following table:

Table 1. 2013 CBC Seismic Coefficients per USGS General Procedure CBC Categorization/Coefficient Design Value (g)
Site Longitude (-117.18971) Site Latitude (33.55249)
Site Class Definition D
Mapped Spectral Response Acceleration at 0.2s Period, Ss 2.06 Mapped Spectral Response Acceleration at 1s Period, S1 0.84 Short Period Site Coefficient at 0.2s Period, Fa 1.00
Long Period Site Coefficient at 1s Period, Fv 1.50
Adjusted Spectral Response Acceleration at 0.2s Period, SMS 2.06 Adjusted Spectral Response Acceleration at 1s Period, SM1 1.26 Design Spectral Response Acceleration at 0.2s Period, SDS 1.37 Design Spectral Response Acceleration at 1s Period, SD1 0.84 * g- Gravity acceleration
The results of the analysis also indicate that the adjusted Peak Ground Acceleration (PGAM) for this site is 0.84g.

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3.6 Secondary Seismic Hazards
Ground shaking can induce “secondary” seismic hazards such as liquefaction, dynamic densification, and ground rupture, as discussed in the following subsections:

3.6.1 Dynamic Settlement (Liquefaction and/or Dry Settlement) A portion of the site contains a Riverside County Liquefaction Hazard zone primarily in a previous drainage alignment. Liquefaction is the loss of soil strength or stiffness due to a buildup of pore-water pressure during severe ground shaking. Liquefaction is associated primarily with loose (low density), saturated, fine- to medium-grained, cohesionless soils. Due to proposed remedial grading of alluvium in natural drainages, the lack of shallow groundwater and relatively dense nature of underlying materials (dense Pauba formation), the potential for liquefaction/dynamic-induced settlement is considered very low or less than 0.5 inch. If occurred, this settlement is expected to be generally global and over a large area. As such, the differential seismic settlement is expected to be less than 0.25- inch in a 30-foot horizontal distance within this site.

3.6.2 Ground Rupture
Since this site is not located within a mapped Alquist Priolo Fault Hazard Zone, the possibility of ground surface-fault-rupture is very low at this site.

However, due to a County Fault Hazard zone encroaching into the western portion of the property, we recommend that no buildings for human occupancy should be proposed in this area (See Figure 4).

In addition, we reviewed sequential pairs of historical aerial photographs and found no evidence of active faulting within the subject site. A listing of aerial photographs reviewed for this site is included with the references attached to this report. As-such, the potential for ground rupture to occur onsite is considered very low.

3.6.3 Rock Falls
The potential for rock fall due to either erosion or seismic ground shaking is considered non-existent in this area.

3.6.4 Seiches, Tsunamis, Inundation Due to Large Water Storage Facilities Due to the great distance to large bodies of water, the possibility of seiches and tsunamis impacting the site is considered remote.

3.6.5 Slope Stability and Landslides
Due to the relatively modest relief across the site and anticipated graded slope heights, the risk of deep-seated slope failure on this site or adjacent Geotechnical Exploration Report 10791.002
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sites is considered very low. The site is not considered susceptible to seismically induced landslides. The open graded channel crossing the site may experience surficial slumping and erosion if left in its current unprotected state

3.6.6 Subsidence
In accordance with County of Riverside Geologic Hazard Maps, the site is located within an area susceptible to subsidence. However, evidence of differential subsidence and associated ground fissuring was not observed during our field exploration or original site grading. As such, we consider the potential for differential subsidence and ground fissuring on this site to be very low.

3.7 Preliminary Percolation/Infiltration Rates
Percolation testing was performed to obtain preliminary percolation/infiltration rates for design of retention basins. The tests were performed in general accordance with the Riverside County Flood Control guidelines for BMP’s (County, 2011). Results reported below are the most conservative readings in minutes per inch drop. The infiltration rates were estimated using the Prochet Method.

Table 2. Summary of Percolation/Infiltration Testing
Test
#
Area Location
(see Plate 1)
Depth
BGS (ft)
Percolation
Rate (min/in)
Infiltration Rate
(in/hr) Soil Description
P-1 Northeast Property 4.0 7.5 0.76 Lt. Gray Brown Silty Sand/Alluvium
P-2 North Central Property 4.0 60 0.09 Silty Sand/Pauba Formation
P-3 South Central Property 4.0 60 0.09 Silty Sand/Pauba Formation
P-4 Southeast Property 4.0 30 0.19 Silty Sand/Pauba
Formation
As indicated above, the infiltration rates appear to be relatively low in the Pauba formation varying from 0.09 to 0.19 in/hr. Infiltration rates in the alluvium are expected to be higher based on test P-1 results (0.76 in/hr).

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4.0 C O N C L U S I O N S A N D R E C O M M E N D AT I O N S

4.1 General
The proposed site development appears feasible from a geotechnical viewpoint provided that the following recommendations are incorporated into the design and construction phases of development. The main geotechnical concern on this site is the potential for high expansive silty/clayey layers within the Pauba formation.

However, we believe that the recommended remedial earthwork provided below will properly address this concern.

4.2 Earthwork
Earthwork should be performed in accordance with the following recommendations and the Earthwork and Grading Specifications included in Appendix D of this report. In case of conflict, the following recommendations should supersede those in Appendix D. The contract between the Owner and the earthwork contractor should be worded such that it is the responsibility of the contractor to place fill properly and in accordance with recommendations presented in this report, including the guide specifications in Appendix D, notwithstanding the testing and observation of the geotechnical consultant.

Prior to grading, the proposed structural improvement areas (i.e. all-structural fill areas, pavement areas, buildings, etc.) should be cleared of surface debris and subsurface pipelines and obstructions (septic tanks/leach fields, foundations etc.).

Septic tanks, seepage pits, or wells, if encountered, should be abandoned in accordance with the City of Murrieta or County guidelines. Voids created by removal of below grade material should be backfilled with properly compacted soil in general accordance with the recommendations of this report. Heavy vegetation, roots and debris should be disposed of offsite.

4.2.1 Remedial Grading
The near surface soils composed of undocumented fill, alluvium and highly weathered Pauba formation are potentially compressible and should be removed and replaced with properly compacted fill for uniform support of structural fills, slopes, pavements and foundations. Acceptability of all removal bottoms should be reviewed by an engineering geologist or geotechnical engineer and documented in the as-graded geotechnical report.

The removal limit should be established by a 1:1 (horizontal:vertical) projection from the edge of fill soil limits downward and outward to competent Geotechnical Exploration Report 10791.002
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material identified by the geotechnical consultant. Removal will also include benching into competent material as the fills rise. The depth of removal should be as follows:
 Building Areas: whether in a fill or cut condition, the depth of removal should extend a minimum of 3 to 4 feet below existing or finish grades to remove any potentially compressible or expansive soils within upper 3 feet below foundations/slabs. Deeper removal may be required in localized areas based on prevailing subgrade conditions during grading. Subgrade soils should consist of compacted very low expansive soils (EI<21). Over-excavation should encompass the entire building pad or extend laterally beyond the building limits a horizontal distance equal to the depth of over-excavation.  Pavement Areas: whether in a fill or cut condition, the depth of removal should extend a minimum of 2 feet BGS (to competent material) or below pavement subgrade, whichever is deeper.

Subgrade should consist of compacted low expansive soils (EI<51).

After completion of the recommended removal and prior to placing additional fill, the approved bottom of removal should be scarified a minimum of 8 inches, moisture conditioned and compacted to a minimum 90 percent of the maximum dry density in accordance with ASTM D1557.

4.2.2 Cut/Fill Transition Building Pads
Where applicable and in order to mitigate the impact of underlying cut/fill transition conditions underlying building foundations, we recommend overexcavation of one-half of the maximum fill thickness on the building pad (not to exceed 5 feet). Overexcavation bottoms should be sloped as needed to the deepest fill contact area to reduce the accumulation of subsurface water.

The actual overexcavation limits and depths will be dependent on building locations and planned grading at those building locations.

4.2.3 Structural Fills
The onsite soils are generally suitable for reuse as compacted fill, provided they are free of organic materials, expansive soils, debris, and oversize materials (greater than 8 inches in greatest dimension). Topsoil and vegetation layers, root zones, and similar surface materials should be striped and stockpiled or removed from the site. The optimum lift thickness to produce a uniformly compacted fill will depend on the type and size of compaction equipment used. In general, fill should be placed in uniform lifts not exceeding 8 inches in thickness. Fill soils should be placed and compacted to a minimum 90 percent relative compaction (as determined by ASTM Test Method D1557) and at or above the optimum moisture content.

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Fills placed on slopes steeper than 5:1 (horizontal: vertical) should be benched into dense soils (see Appendix D for benching detail). Benching should be of sufficient depth to remove all loose material. A minimum bench height of 2 feet into approved material should be maintained at all times Placement and compaction of fill should be performed in accordance with the City of Murrieta Grading Ordinance and recommendations of Appendix D, under the full-time observation and testing of the geotechnical engineer. Fill materials with expansion index greater than 21 should not be used in upper 3 feet of subgrade soils below building pads. If cobbles and boulders larger than 6-inches in largest diameter are encountered or produced during grading, these oversized cobbles and boulders should be reduced to less than 6 inches or placed in structural fill as outlined in Appendix D.

4.2.4 Slope Construction
Fill slope keyways will be necessary at the toe of all fill slopes and at fill-overcut contacts. Keyway schematics, including dimensions and subdrain recommendations, are provided in Appendix D. All keyways should be excavated into dense Pauba formation as determined by the geotechnical engineer. The cut portions of all slope and keyway excavations should be geologically mapped and approved by a geologist prior to fill placement.

Compacted fill or cut slopes up to 20 feet in height at 2:1 (horizontal:vertical) are considered grossly stable for static and pseudostatic conditions. Higher or steeper slopes should be subject to further review and evaluation.

The outer portion of fill slopes should be either overbuilt by 2 feet (minimum) and trimmed back to the finished slope configuration or compacted in vertical increments of 5 feet (maximum) by a weighted sheepsfoot roller as the fill is placed. The slope face should then be track-walked by dozers of appropriate weight to achieve the final slope configuration and compaction of slope face.

Slope faces are inherently subject to erosion, particularly if exposed to rainfall and irrigation. Landscaping and slope maintenance should be conducted as soon as possible in order to increase long-term surficial stability. Berms and or v-ditch drainage devises should be provided at the top of all slopes.

Drainage should be directed such that surface runoff on the slope face is minimized.

4.2.5 Import Soils
Import soils and/or borrow sites, if needed, should be evaluated by us prior to import. Import soils should be uncontaminated, granular in nature, free of organic material (loss on ignition less-than 2 percent), have very low Geotechnical Exploration Report 10791.002
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expansion potential (E<21) and have a low corrosion impact to the proposed improvements.

4.2.6 Utility Trenches
Utility trenches should be backfilled with compacted fill in accordance with Sections 306-1.2 and 306-1.3 of the Standard Specifications for Public Works Construction, (“Greenbook”), 2012 Edition. Fill material above the pipe zone should be placed in lifts not exceeding 8 inches in uncompacted thickness and should be compacted to at least 90 percent relative compaction (ASTM D 1557) by mechanical means only. Site soils may generally be suitable as trench backfill provided these soils are screened of rocks over 1½ inches in diameter and organic matter. If imported sand is used as backfill, the upper 3 feet in building and pavement areas should be compacted to 95 percent. The upper 6 inches of backfill in all pavement areas should be compacted to at least 95 percent relative compaction.

Where granular backfill is used in utility trenches adjacent moisture sensitive subgrades and foundation soils, we recommend that a cut-off “plug” of impermeable material be placed in these trenches at the perimeter of buildings, and at pavement edges adjacent to irrigated landscaped areas. A “plug” can consist of a 5-foot long section of clayey soils with more than 35- percent passing the No. 200 sieve, or a Controlled Low Strength Material (CLSM) consisting of one sack of Portland-cement plus one sack of bentonite per cubic-yard of sand. CLSM should generally conform to requirements of the “Greenbook”. This is intended to reduce the likelihood of water permeating trenches from landscaped areas, then seeping along permeable trench backfill into the building and pavement subgrades, resulting in wetting of moisture sensitive subgrade earth materials under buildings and pavements.

Excavation of utility trenches should be performed in accordance with the project plans, specifications and the California Construction Safety Orders (latest Edition). The contractor should be responsible for providing a "competent person" as defined in Article 6 of the California Construction Safety Orders. Contractors should be advised that sandy soils (such as fills generated from the onsite alluvium) could make excavations particularly unsafe if all safety precautions are not properly implemented. In addition, excavations at or near the toe of slopes and/or parallel to slopes may be highly unstable due to the increased driving force and load on the trench wall.

Spoil piles from the excavation(s) and construction equipment should be kept away from the sides of the trenches. Leighton Consulting, Inc. does not consult in the area of safety engineering.

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4.2.7 Temporary Slope Stability
Existing site soils and or graded artificial fill should be considered as OSHA soil Type C. Therefore, unshored temporary cut slopes should be no steeper than 1½:1 (horizontal:vertical), for a height no-greater-than 20 feet (California Construction Safety Orders, Subchapter 4, Section 1541.1, Table B-1).

During construction, exposed earth material conditions should be regularly evaluated to verify that conditions are as anticipated. The contractor should be responsible for providing the "competent person" required by OSHA standards to evaluate soil conditions. Close coordination between the competent person and geotechnical consultant should be maintained to facilitate construction while providing safe excavations.

4.2.8 Shrinkage
The volume change of excavated onsite soils upon recompaction is expected to vary with materials, density, insitu moisture content, and location and compaction effort. The in-place and compacted densities of soil materials vary and accurate overall determination of shrinkage and bulking cannot be made. Therefore, we recommend site grading include, if possible, a balance area or ability to adjust grades slightly to accommodate some variation.

Based on our geotechnical laboratory test results, we expect recompaction shrinkage (when recompacted to an average 92 percent of ASTM D1557) of 5- to 10-percent by volume for the existing alluvium or Pauba formation materials.

4.2.9 Drainage
All drainage should be directed away from structures, slopes and pavements by means of approved permanent/temporary drainage devices. Adequate storm drainage of any proposed pad should be provided to avoid wetting of foundation soils. Irrigation adjacent to buildings should be avoided when possible. As an option, sealed-bottom planter boxes and/or drought resistant vegetation should be used within 5-feet of buildings.

4.3 Foundation Design
Shallow spread or continuous wall footings bearing on a newly placed properly compacted fill are anticipated for the proposed structures.

4.3.1 Design Parameters – Spread/Continuous Shallow Footings Footings should be embedded at least 12-inches below lowest adjacent grade for the proposed structure. Footing embedment should be measured from lowest adjacent finished grade, considered as the top of interior slabson-grade or the finished exterior grade, excluding landscape topsoil, whichever is lower. Footings located adjacent to utility trenches or vaults Geotechnical Exploration Report 10791.002
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should be embedded below an imaginary 1:1 (horizontal:vertical) plane projected upward and outward from the bottom edge of the trench or vault, up towards the footing.
 Bearing Capacity: For footings founded on newly placed, properly compacted fill soil, an allowable vertical bearing capacity of 2,000 pounds-per-square-foot (psf) should be used. . The bearing pressure value may be increased by 250 psf for each additional foot of embedment or each additional foot of width to a maximum vertical bearing value of 3,000 psf. These bearing values may be increased by one-third when considering short-term seismic or wind loads. All continuous perimeter or interior footings should be reinforced with at least one No. 5 bar placed both top and bottom.
 Lateral loads: Lateral loads may be resisted by friction between the footings and the supporting subgrade. A maximum allowable frictional resistance of 0.35 may be used for design. In addition, lateral resistance may be provided by passive pressures acting against foundations poured neat against properly compacted granular fill. We recommend that an allowable passive pressure based on an equivalent fluid pressure of 350 pounds-per-cubic-foot (pcf) be used in design. These friction and passive values have already been reduced by a factor-of-safety of 1.5.

4.3.2 Design Parameters – Light Poles
For light poles or any other similar structure founded on 24- or 30-inch drilled piers extending to a minimum of 5 feet below proposed finish grade, the following geotechnical parameters should be considered for design:
 An allowable end bearing pressure of 3,000 psf may be used if the pier is embedded a minimum of 7 feet into compacted fill or competent Pauba formation bedrock. An increase of 250 psf may be applied for every foot of depth thereafter, to a maximum pressure of 5,000 psf. A one-third increase in allowable pressure may be used for short duration loads as wind or seismic.
 Uplift resistance should be limited to the weight of the pier plus 800 psf of skin friction for the portion of pier below 3 feet. Resistance to lateral loads will be provided by the passive earth pressure against the sides of the pier. The passive earth pressure may be computed as an equivalent fluid having a density of 300 psf per foot of depth, to a maximum earth pressure of 4,500 psf.

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The above allowable pressures are based on soil characteristics only. The structural engineer should check the allowable pressures permitted by the selected caisson size and materials.

4.3.3 Interior Slab Design
Slab-on-grade floors utilized with conventional foundations should be designed with a minimum thickness as indicated by the project structural engineer consistent with a modulus of subgrade reaction of 200 poundsper-square-inch per inch (pci) and reinforced in accordance with the structural engineer’s recommendations.

A moisture retarder should be installed underneath all slabs where moisture condensation is undesirable. The vapor retarder should be sealed at all penetrations and laps and properly installed in accordance with the recommendations of the architect, concrete subcontractor, and the manufacturer’ recommendations. Moisture vapor retarders may retard but not eliminate moisture vapor movement from the underlying soils up through the slabs. Moisture vapor transmission may be additionally reduced by use of concrete additives. A slipsheet or equivalent should be utilized above the concrete slab if crack-sensitive floor coverings (such as ceramic tiles, etc.) are to be placed directly on the concrete slab It is been a standard of care to place a 10-mil Visqueen moisture retarder (or equivalent) underneath all moisture sensitive slabs. This moisture retarder is typically covered by a 2-inch layer of sand (SE of 30 or greater) to reduce curling. Visqueen sheets should overlap at least 6-inches. If storage of moisture sensitive records (files) or floor coverings (e.g. vinyl tile, etc.) are to be used, additional moisture mitigation measures may be employed within or beneath concrete slab-on-grade floors. Moisture retarders do not completely eliminate moisture vapor movement from the underlying soils up through the slabs or from the unbonded water in the concrete. To further reduce moisture vapor emissions that may result in delamination and other tile damage, we recommend that moisture retarder specialist be consulted.

4.3.4 Settlement Estimates
For settlement estimates, we assumed that column loads will be no larger than 120 kips, with bearing wall loads not exceeding 5.0 kips per foot of wall. If greater column or wall loads are required, we should re-evaluate our foundation recommendation, and re-calculate settlement estimates.

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Buildings located on properly compacted fill soils as required per Section

4.2.1 should be designed in anticipation of 1 inch of total settlement and 1/2-inch of differential settlement within a 40 foot horizontal run.

4.4 Footing Setback
We recommend a minimum horizontal setback distance from the face of slopes for all structural footings (retaining and decorative walls, building footings, etc.). This distance is measured from the outside bottom edge of the footing horizontally to the slope face (or to the face of a retaining wall) and should be a minimum of H/2, where H is the slope height (in feet). The setback should not be less than 7 feet and need not be greater than 20 feet for this project.

Note that the soils within the structural setback area possess poor lateral stability and improvements (such as retaining walls, sidewalks, fences, pavements, etc.) constructed within this setback area may be subject to lateral movement and/or differential settlement. Potential distress to such improvements may be mitigated by providing a deepened footing or a pier and grade-beam foundation system to support the improvement. The deepened footing should meet the setback as described above.

4.5 Retaining Walls
Retaining wall earth pressures are a function of the amount of wall yielding horizontally under load. If the wall can yield enough to mobilize full shear strength of backfill soils, then the wall can be designed for "active" pressure. If the wall cannot yield under the applied load, the shear strength of the soil cannot be mobilized and the earth pressure will be higher. Such walls should be designed for "at rest" conditions. If a structure moves toward the soils, the resulting resistance developed by the soil is the "passive" resistance. Retaining walls backfilled with non-expansive soils can be designed using the following equivalent fluid pressures:

Table 3. Retaining Wall Design Earth Pressures (Static, Drained) Loading
Conditions
Equivalent Fluid Density (pcf)
Level Backfill 2:1 Sloped Backfill
Active 37 55
At-Rest 55 75
Passive* 300 150 (2:1, sloping down)
* This assumes level condition in front of the wall will remain for the duration of the project, not to exceed 3,500 psf at depth.

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Unrestrained (yielding) cantilever walls should be designed for the active equivalent-fluid weight value provided above for very low to low expansive soils that are free draining (see Appendix D for typical drainage). In the design of walls restrained from movement at the top (non-yielding) such as basement or elevator pit/utility vaults, the at-rest equivalent fluid weight value should be used. Total depth of retained earth for design of cantilever walls should be measured as the vertical distance below the ground surface measured at the wall face for stem design, or measured at the heel of the footing for overturning and sliding calculations. Should a sloping backfill other than a 2:1 (horizontal:vertical) be constructed above the wall (or a backfill is loaded by an adjacent surcharge load), the equivalent fluid weight values provided above should be re-evaluated on an individual case basis by us. Non-standard wall designs should also be reviewed by us prior to construction to check that the proper soil parameters have been incorporated into the wall design.

All retaining walls should be provided with appropriate drainage. The outlet pipe should be sloped to drain to a suitable outlet. Wall backfill should be nonexpansive (EI  21) sands compacted by mechanical methods to a minimum of 90 percent relative compaction (ASTM D 1557). Walls should not be backfilled until wall concrete attains the 28-day compressive strength and/or as determined by the Structural Engineer that the wall is structurally capable of supporting backfill.

Lightweight compaction equipment should be used, unless otherwise approved by the Structural Engineer.

4.6 Sulfate Attack
The results of our laboratory testing on a representative sample are included in Appendix B (negligible exposure effect). Further testing should be performed at the completion of site grading to confirm soluble-sulfate content in onsite subgrade soils.

4.7 Preliminary Pavement Design
The preliminary pavement design provided below is based on the locally accepted Caltrans Highway Design Manual and an average R-value of 15 based on our laboratory testing. For planning and estimating purposes, the pavement sections are calculated based on Traffic Indexes (TI) indicated in Table below and provided Geotechnical Exploration Report 10791.002
Proposed CarMax Automotive Dealership October 3, 2014
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by CarMax. Pavement design calculations are included in Appendix C and reflect design criteria of 20 years life span.

Table 4. Asphalt Pavement Sections
General Traffic
Condition
Traffic
Index (TI)
Comparable
ESAL’s
Hot Mix Asphalt
HMA (inches)
Aggregate Base*
AB (inches)
Automobile Parking
Stalls 4.5 < 4,700 4.0 4.0
Light Duty Automobile
Drive Lane/Parking 5.0 4,700 to
10,900 4.0 6.0
Heavy Duty Drive &
Truck Access 6.5 47,300 to 89,800 4.0 11.5
*Design pavement calculations are included in Appendix C.

Location of applicable Traffic Index (TI) should be designated by the project civil engineer. Actual R-value of the subgrade soils should be verified after completion of site grading to finalize the pavement design. Per CarMax requirement, the HMA layer should be a minimum of 4 inches in thickness and placed in two layers.

Based on local practices, the surface course should be a minimum of 1.5 inches thick and consist of Type C2 PG70-10 per Section 203-6 of the “Standard Specifications for Public Works Construction” (Greenbook), current edition. The base course should be a minimum of 2.5 inches thick and consist of Type B PG70-

10. Other HMA grades or mixes may be specified by Client and/or Architect pending approval by City and conforming to applicable Greenbook requirements.

Where applicable, we recommend that a minimum of 6 inches of PCC pavement be used, in high impact load areas or if to be subjected to truck traffic. The PCC pavement should be placed on a minimum 6-inch aggregate base. The PCC pavement may be placed directly on a compacted subgrade with an R-Value of 40 or higher. The PCC pavement should have a minimum of 28-day flexural strength of 650 psi. Design and placement of concrete materials should be follow applicable ACI and City standards.

The upper 8 inches of pavement area subgrade soils should be moistureconditioned to near optimum moisture content, compacted to at least 95 percent relative compaction (ASTM D1557) and kept in this condition until the pavement section is constructed. Minimum relative compaction requirements for aggregate base should be 95 percent of the maximum laboratory density as determined by Geotechnical Exploration Report 10791.002
Proposed CarMax Automotive Dealership October 3, 2014
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ASTM D1557. If applicable, aggregate base should conform to Greenbook or Caltrans Class 2 aggregate base.

If pavement areas are adjacent to heavily watered landscape areas, some deterioration of the subgrade load bearing capacity may result. Moisture control measures such as deepened curbs or other moisture barrier materials may be used to prevent the subgrade soils from becoming saturated. The use of concrete cutoff or edge barriers should be considered when pavement is planned adjacent to either open (unfinished) or irrigated landscaped areas.

Geotechnical Exploration Report 10791.002
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5.0 G E O T E C H N I C AL C O N S T R U C T I O N S E R V I C E S Geotechnical review is of paramount importance in engineering practice. Poor performances of many foundation and earthwork projects have been attributed to inadequate construction review. We recommend that Leighton Consulting, Inc. be provided the opportunity to review the grading plan and foundation plan(s) prior to bid.

Reasonably-continuous construction observation and review during site grading and foundation installation allows for evaluation of the actual soil conditions and the ability to provide appropriate revisions where required during construction. Geotechnical conclusions and preliminary recommendations should be reviewed and verified by Leighton Consulting, Inc. during construction, and revised accordingly if geotechnical conditions encountered vary from our findings and interpretations. Geotechnical observation and testing should be provided:
 After completion of site demolition and clearing,
 During over-excavation of compressible soil,
 During compaction of all fill materials,
 After excavation of all footings and prior to placement of concrete,  During utility trench backfilling and compaction, and  When any unusual conditions are encountered.

Additional geotechnical exploration and analysis may be required based on final development plans, for reasons such as significant changes in proposed structure locations/footprints. We should review grading (civil) and foundation (structural) plans, and comment further on geotechnical aspects of this project.

Geotechnical Exploration Report 10791.002
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6.0 L I M I T AT I O N S
This report was based in part on data obtained from a limited number of observations, site visits, soil excavations, samples and tests. Such information is, by necessity, incomplete. The nature of many sites is such that differing soil or geologic conditions can be present within small distances and under varying climatic conditions. Changes in subsurface conditions can and do occur over time. Therefore, our findings, conclusions and recommendations presented in this report are based on the assumption that we (Leighton Consulting, Inc.) will provide geotechnical observation and testing during construction as the Geotechnical Engineer of Record for this project.

Please refer to Appendix E, ASFE’s Important Information About Your Geotechnical Report, prepared by the Associated Soil and Foundation Engineers (ASFE) presenting additional information and limitations regarding geotechnical engineering studies and reports.

This report was prepared for the sole use of Client and their design team, for application to design of the proposed maintenance building, in accordance with generally accepted geotechnical engineering practices at this time in California. Any unauthorized use of or reliance on this report constitutes an agreement to defend and indemnify Leighton Consulting, Inc. from and against any liability which may arise as a result of such use or reliance, regardless of any fault, negligence, or strict liability of Leighton Consulting, Inc.

Geotechnical Exploration Report 10791.002
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R E F E R E N C E S
Army Corps of Engineers, Evaluation of Settlement for Dynamic and Transient Loads, Technical Engineering and Design Guides as Adapted from the US Army Corps of Engineers, No. 9, American Society of Civil Engineers Press.

American Society of Civil Engineers, 2010, Minimum Design Loads for Buildings and Other Structures, ASCE/SEI 7-10 Publication.

Bryant, W. A. and Hart, E.W., 2007, Fault-Rupture Hazard Zones in California, AlquistPriolo Earthquake Fault Zoning with Index to Earthquake Zones Maps:

Department of Conservation, Division of Mines and Geology, Special Publication

42. Interim Revision 2007.

California Building Code, 2013, California Code of Regulations Title 24, Part 2, Volume 2 of 2.

California Department of Water Resources, 2014, Water Data Library, viewed August 27, 2014, www.water.ca.gov/waterdatalibrary.

California Geologic Survey (CGS), 2003. The Revised 2002 California Probabilistic Seismic Hazard Maps, June 2003. By Tianquing Cao, William A. Bryant, Badie Rowshandel, David Branum and Christopher J. Wills.

California Geological Survey, (CGS), 2006, Geologic Map of the San Bernardino and Santa Ana 30’ X 60’ Quadrangle, Southern California, Version 1.0, Compiled by Douglas M. Morton and Fred K. Miller, Open File Report 06-1217.

Kennedy, M.P., 1977, "Recency and Character of Faulting Along the Elsinore Fault Zone in Southern Riverside County, California", Special Report 131.

Public Works Standard, Inc., 2012, Greenbook, Standard Specifications for Public Works Construction: 2012 Edition, BNI Building News, Anaheim, California.

Riverside County, 2003, County of Riverside General Plan, Riverside County Integrated Project Website.

Riverside County, 2011, Design Handbook for Low Impact Development- BMP, prepared by RCFC&WCD
Tokimatsu, K., and Seed, H.B., 1987, Evaluation of Settlements in Sands Due to Earthquake Shaking, ASCE Journal of Geotechnical Engineering, Vol. 113, No. 8, dated August.

Geotechnical Exploration Report 10791.002
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USGS, 2014, A Web Based Computer Program Published by USGS to calculate Seismic Hazard Curves and Response and Design Parameters based on ASCE 7-10 seismic procedures.

Aerial Photographs Reviewed
Flight Date Flight Photograph No.
8-28-53 1952/3 AXM AXM-2K- 129/130
1-28-62 RCFC 62 1-57/18
6-25-68 R62568 2/3
12-8-83 RCFC 396/397
Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors, Source: Esri, DigitalGlobe, GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community ³ 0 2,000 4,000
Feet
Figure 1
Scale:

Leighton
Base Map: ESRI ArcGIS Online 2014
Thematic Information: Leighton
1 " = 2,000 '
Project: 10791.002 Eng/Geol:

Map Saved as V:\drafting\10791\002\Maps\10791-002_F01_SLM_20140902.mxd on 9/5/2014 9:42:53 AM Author: Leighton Geomatics (cgiovando)
Date: October 2014 SITE LOCATION MAP
Proposed CarMax
Murrieta, California
Approximate
Site Location
pKm
Qya
Qss Qss
Qya
Qya
Qss
Qyf
Qss
Tv
Qss
Qya Qya
Tv
Qoa
Qya
Qvoa
gr
gr
Qya
gr
Qyf
Qss
Qss
gr
Tv
Qls
Qyf
Copyright:© 2013 National Geographic Society, i-cubed, Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors
³ 0 4,000 8,000
Feet
Figure 2
Scale:

Leighton
Base Map: ESRI ArcGIS Online 2014
Thematic Information: Leighton
1 " = 4,000 '
Project: 10791.002 Eng/Geol:

Map Saved as V:\drafting\10791\002\Maps\10791-002_F02_RGM_20140903.mxd on 9/5/2014 9:40:03 AM Author: Leighton Geomatics (cgiovando)
Date: October 2014 REGIONAL GEOLOGIC MAP
Proposed CarMax
Murrieta, California
Approximate
Site Location
Legend
Qls - Landslide Deposits; may include debris flows and
older landslides
Qoa - Old Alluvial Valley
! Qss - Coarse-grained formations of Pleistocene age
and younger; primarily sandstone and conglomerate
Qvoa - Very Old Alluvial Valley
!!!
! !
! !! !
!
!
! !
!
Qya - Young Alluvial Valley
Qyf - Young Alluvial Fan
Tv - Tertiary age formations of volcanic origin
gr - Granitic and other intrusive crystalline rocks of all ages
pKm - Cretaceous and Pre-Cretaceous metamorphic
formations of sedimentary and volcanic origin
Copyright:© 2013 National Geographic Society, i-cubed, Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors
³ 0 4,000 8,000
Feet
Figure 3
Scale:

Leighton
Base Map: ESRI ArcGIS Online 2014
Thematic Information: Leighton
1 " = 4,000 '
Project: 10791.002 Eng/Geol:

Map Saved as V:\drafting\10791\002\Maps\10791-002_F03_LHM_20140903.mxd on 9/5/2014 10:02:18 AM Author: Leighton Geomatics (cgiovando)
Date: October 2014 LIQUEFACTION HAZARD MAP
Proposed CarMax
Murrieta, California
Approximate
Site Location
Legend
Liquefaction
Susceptibility
Very High
High
Moderate
Low
Very low
Willard Fault
S
Murrieta Hot
prings Fault
Unnamed fault in
Elsinore fault zone
Wildomar
Fault
Wildomar Fault
Murrieta Hot
Springs Fault

ELSINORE FAULTS

ELSINORE
FAULT
fault in
basement rocks

ELSINORE
FAULT
Unnamed fault in
Elsinore fault zone

ELSINORE
FAULT

ELSINORE
FAULT
Wildomar Fault
Source: Esri, DigitalGlobe, GeoEye, i-cubed, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community, Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors
³
0 2,000 4,000
Feet
Figure 4
Scale:

Leighton
Base Map: ESRI ArcGIS Online 2014
Thematic Information: Leighton
1 " = 2,000 '
Project: 10791.002 Eng/Geol:

Map Saved as V:\drafting\10791\002\Maps\10791-002_F04_CHFM_20140902.mxd on 9/15/2014 4:55:39 PM Author: Leighton Geomatics (mmurphy)
Date: October 2014 COUNTY FAULT HAZARD ZONE
Proposed CarMax
Murrieta, California
Approximate
Site Location
Legend
Holocene
Late Quaternary
Quaternary

COUNTY FAULT ZONE

ELSINORE FAULT ZONE
&<
&<
&< &<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&<
&(
&(
&(
&<
&(
LB-1
LB-2
LB-3 LB-4
LB-5
LB-6
LB-7
LB-8
LB-9
LB-10
LB-11
LB-12
LB-13
LB-14
LB-15
LB-16
LB-17
LB-18
LB-19
LB-20
LB-21
LB-22
LB-23
LB-24
LB-25
LB-26
LB-27
LB-28
LB-29
LB-30
LB-31
LB-32
LB-33
LB-34
LB-36
LB-37
LB-38
LB-39
LB-40
P-1
P-2
P-4
LB-35
P-3
Afu
Qal
Qps
Qps
Qps
Qps
Qps
Qps
Qps
Qps
Qps
Qps
Afu
Afu
Afu
Afu
Afu Qal
Qal
Qal
Qal
Qal
Qal
Qps
Qps
Qal
Afu
Esri, HERE, DeLorme, MapmyIndia, © OpenStreetMap contributors, Source: Esri, DigitalGlobe, GeoEye, i-cubed, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community Legend
&< Approximate Location of Exploratory Boring
&( Approximate Location of Infiltration Test
Afu undocumented Fill
Qal Alluvium
Qps Pauba formation
Approximate Geologic Contact
Proposed Improvements
Property Limits
³ 0 100 200
Feet
Project: 10791.002
Scale: Date: October 2014
Eng/Geol:
1 " = 100 feet
Base Map: ESRI ArcGIS Online 2014
Thematic Information: Leighton
Author: Leighton Geomatics (cgiovando)
Map Saved as V:\drafting\10791\002\Maps\10791-002_P01_GTM_20140902.mxd on 9/15/2014 4:52:12 PM

GEOTECHNICAL AND BORING LOCATION MAP
Proposed CarMax
Murrieta, California
Plate 1
Leighton
P-4
LB-40
Geotechnical Exploration Report 10791.002
Proposed CarMax Automotive Dealership October 3, 2014

APPENDIX A

LOGS OF EXPLORATORY BORINGS / FIELD EXPLORATION
Encountered earth materials were logged and sampled in the field by our representative and described in accordance with the Unified Soil Classification System (ASTM D 2488). During drilling, bulk and relatively undisturbed ring-lined split-barrel driven earth material samples were obtained from our borings for geotechnical laboratory testing and classification. Drive-samples were driven with a 140-pound auto-hammer falling 30- inches. Samples were transported to our in-house Temecula laboratory for geotechnical testing. After logging and sampling, our borings were backfilled with spoils generated during drilling.

The attached subsurface exploration logs and related information depict subsurface conditions only at the locations indicated and at the particular date designated on these logs. Subsurface conditions at other locations may differ from conditions occurring at these logged locations. Passage of time may result in altered subsurface conditions due to environmental changes. In addition, any stratification lines on these logs represent an approximate boundary between sampling intervals and soil types; and transitions may be gradual.

SM
ML
SW-SM
SM
B-1
R-1
R-2
R-3
R-4
Pauba Formation (Qps); SILTY SAND with GRAVEL, light brownish gray, dry to moist, fine to coarse grained sand with fine gravel SILTY SAND, light brownish gray, dry to moist, fine to medium grained sand
SILTY SAND, dense, light brown, dry to moist, fine to medium grained sand
SILT with SAND, light brownish gray, moist, fine to medium grained sand
Well-graded SAND with SILT and GRAVEL, dense, brown, moist, fine to coarse sand with fine gravel Well-graded SAND with SILT, dense, brown, moist, fine to coarse grained sand SILTY SAND, dense, olive gray, moist, fine to medium grained sand, iron oxide staining
Total Depth = 20.92' bgs, no groundwater encountered, backfilled with cuttings on 08/11/14 50 16
30 43
22 32
37 25
50/5"
~1112'

BULK SAMPLE

CORE SAMPLE

GRAB SAMPLE

RING SAMPLE

SPLIT SPOON SAMPLE

TUBE SAMPLE
B
C
G
R
S
T
JTD
H - 140lb - Autohammer - 30" Drop Soil Class.
8-11-14

SOIL DESCRIPTION
Sampled By
Drilling Co.

Project
Project No.

See Plate 1
Proposed CarMax, Murrieta
10791.001
Drilling Method
8" Sample No. Feet
Hole Diameter Moisture
Ground Elevation
Depth
0 5
10 15
20 25
30 Blows Elevation Per 6 Inches