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Home My WebLink Abouthecate_ortega_bess_substation_geotech_rpt_rev_122321 Proposed Hecate Ortega BESS and Substation Geotechnical Investigation Report ® Stantec Prepared for: Hecate Grid ILC 621 W. Randolph Street Chicago, IL60661 Prepared by: Stantec Consulting Serviceslnc. 735 EastCamegie Drive, Suite 280 San Bernardino, CA 92408 Project No. 185805133 April 29,2021 Stantec Consulting Serviceslnc. 735 East Carnegie Drive, Suite 280 Stantec San Bernardino, California 92408 Ap A 29, 2021 Mr. Gabriel Wapner He c ate Grid LLC 621 Randolph Street Chicago, Illinois 60661 RE: G EO'IEC HNIC AL INVESTIG A'IIO N REPORT Ortega Battery Energy Storage System Project Lake Elsinore, Riverside County, California DearMr. Wapner: This letter transmits Stantec Consulting Services Inc.'s (Stantec's) geotechnical investigation report for the 1.79 (+/-) acre site for a proposed battery energy storage system (BESS) development located in Lake Elsinore, Riverside County, California. The purpose of this report is to evaluate the subsurface conditions and provide geotechnical recommendations for design and construction ofthe proposed development. We appreciate the opportunityto workwith you on thisproject. Ifyou have any questions,please callusatthe numbersbelow. Respectfully submitted, STAN'IEC C O NSUL'IING SERVICES INC. q 3EESslONg4 • ��o P�� FISm C 80383 � Ja re t Ftsc e r, * EXP.3131/23 * Eva n Hsia o, GE PrincipalEngine r S'� CIVIC Principal, SeniorGeote7calEngineer Phone: (909) 335-6116 ext. 8 TFOFCAJ Phone: (949) 923-6000 Jaret.Fischer@stantec.com Evan.Hsiao@stantec.com PRO PO SID HEC ATE O RIEG A BESS AND SUBSTATIO N G EO TEC HNIC AL INVESUG ADO N REPO RT Table of Contents 1. INTRODUCTION ............................................................................................................. I 1.1 PRO POSED DEVELO PMENT.......................................................................................... 1 1.2 PURPOSEAND SCOPE OF WORK................................................................................ 1 1.2.1 Purp o se .........................................................................................................1 1.2.2 Scope ofWork..............................................................................................1 2. FIELD INVESTIGATION.................................................................................................... 2 2.1 PRE-DRUJ ING PROCEDURES......................................................................................... 2 2.2 DRILLING OPERATIONS................................................................................................. 2 2.3 SAMPLING ..................................................................................................................... 2 3. LABO RATO RY TESTING .................................................................................................. 4 4. G EO LO G IC SETTING AND SITE C O NDTIIO NS............................................................... 5 4.1 REGI0NALGEOLOGY.................................................................................................. 5 4.2 SURFAC E C 0 NDMO NS................................................................................................. 5 4.3 SUBSURFAC E C O NDIIIO NS........................................................................................... 5 5. G EO LO G IC HAZARDS................................................................................................... 7 5.1 FAULTING AND SURFACE FAULTRUPTURE.................................................................... 7 5.2 C ALIFO RNIA BUILDING C O DE SEISMIC C RMIZIA........................................................ 7 5.3 LIQUEFACTION AND DYNAMIC SETTLEMENT............................................................... 8 5.4 LIQ UEFAC TIO N-INDUC ED LATERAL SPREADING.......................................................... 9 5.5 FLO O DING, TSUNAMIS AND SEIC HES........................................................................... 9 5.6 EXPANSIVE SO ILS........................................................................................................... 9 6. CONCLUSIONS............................................................................................................ 10 7. RECOMMENDATIONS.................................................................................................. 12 7.1 EARTHWORK................................................................................................................12 7.1.1 Site Preparation..........................................................................................12 7.1.2 RemedialGrading .....................................................................................12 7.1.3 Fill Placement and Compaction ..............................................................13 7.1.4 Yielding Subgrade Conditions..................................................................13 7.1.5 Dewatering.................................................................................................14 7.1.6 Expansive Soil.............................................................................................14 7.1.7 Imported Material......................................................................................14 7.1.8 Site Excavation Characteristics ................................................................14 7.1.9 O ve rsize d Ma to ria 1.....................................................................................14 7.1.10 Temporary Exc avations.............................................................................14 7.1.11 Pipelines......................................................................................................15 7.1.12 Surface Drainage.......................................................................................15 7.1.13 Grading Plan Review.................................................................................16 7.2 FOUNDATIONS.............................................................................................................16 7.2.1 Shallow Foundations..................................................................................16 ® Stantec PRO PO SID HEC ATE O RIEG A BESS AND SUBSTATIO N G EO TEC HNIC AL INVESUG ADO N REPO RT 7.2.2 Drilled Pier Foundations.............................................................................17 7.2.3 Foundation Settlement..............................................................................17 7.2.4 La te ra I Re sista nc e ......................................................................................17 7.2.5 Foundation Plan Review ...........................................................................17 7.2.6 Foundation Excavation Observations......................................................17 7.3 C O RRO SIO N PO'IEN IIAL..............................................................................................18 7.4 PRELIMINARY PAVEMENT DESIGN...............................................................................18 7.5 PO STINVESTIG ATIO N SERVIC ES..................................................................................20 8. C LO SURE...................................................................................................................... 21 9. REFERENCES................................................................................................................. 22 LIST OF TABLES Table 1. Summary ofLaboratory Tests.................................................................................... 4 Ta b le 2. Faults in Site Vicinity................................................................................................... 7 Table 3. 2019 CBC Seismic Parameters and Peak Ground Acceleration........................... 7 Table 4. Flexible Pavement Sections.....................................................................................19 Table 5. Concrete Pavement Parameters............................................................................19 Table 6. Recommended Concrete Pavement Sections.....................................................20 LIST OF FIGURES Fig ure 1 — Site Lo c a do n Ma p Figure 2 — Site Vic inity Map Fig ure 3 — Sub surfa c e Exp to ra do n Ma p Figure 4 —Geologic Map LIST OF APPENDIC ES APPENDIX A BORING LOGS...........................................................................................A.I APPENDIX B LABORATORYTESTRESULTS....................................................................... B.1 ® Stantec PROPOSED IIEC A'IE O R'IEG A BESS AND SUBSTA'HO N G EO'IEC HNIC AL INVES'IIG A'HO N REPO RT Introduction Ap H 29,2021 1 . IN'TRO DUC HO N 'Ihis report presents the results of Stantec's geotechnical investigation for the proposed 1.79 (+/-) acre Ortega Battery Energy Storage System (BESS) development in Lake Elsinore, Riverside County, California (the Site). 'Ihe project location is shown on the Site Location Map, Figure I and the approximate area of the proposed development is shown on the Site Vicinity Map, Fig a re 2. 1.1 PRO PO SID DEVELO PMENT Based on similarprojects, the development is expected to consist of shallow mat foundations to support the heavy equipment and shallow pad or spread footings to support light weight equipment. Preliminary development plans forthe proposed project were not available at the time of this report. If actual foundation conditions differ from those indicated above, the recommendations of this report willneed to be re-evaluated and are subjectto change. Given that there are no grading plans available, we have assumed that the final surface elevationswillnotvary significantly from existing site grades. The site grading and foundationplans should be provided to the Project Geotechnical Engineer for review. 'Ilse recommendations in thisreport are subject to change based upon review ofthe site grading and foundation plans. 1 .2 PURPO SE AND SC O PE O F WO RK 1.2.1 Purp o se 'Ihe purpose of this report is to evaluate the subsurface conditions at the Site and provide geotechnicalrecommendations for design and construction ofthe proposed project. This report hasbeen prepared in general accordance with accepted geotechnical engineering principles and in genera lconformance with the approved proposal. 1.2.2 Scope ofWork Ourscope ofworkconsisted ofthe following: • Perform a site reconnaissance to evaluate genera lgeotechnicaIand site conditions, • Pe rfo rm a field subsurface e xp to ra don program consisting of drilling 4 hollow stem augerborings, • Perform geotechnica I laboratory tests on selected samples, • Perform geotechnicalengineering analyses, and • Preparation of this geotechnicalinvestigation report forthe proposed project. ® Stantec fjv:\1858\active\185805133\05_report_daliv\deliverable\reports\hecato_ortega_bass_substation geotoch_rpt_20210429.docx 1 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G EO TEC HNIC AL INVES'IIG ADO N REPO RT Field Investigation Ap ri129,2021 2. FIELD INVESUG AMO N 2.1 PRE-DRILLING PROCEDURES Dig Alert (Underground Service Alert of Southern California) was notified before commencing subsurface exploration activities to identify underground utilities that could conflict with the proposed borings. In addition, a private utility locatorwas retained, and the upperfive feet were hand augered to clearthe boring locations forpotentialconflictswith underground utilities. 2.2 DRIIiING O PERA'IIO NS Fourtest borings (B1 through B4) were drilled using a CME 85 drillrig equipped with hollow-stem augers(HSA) on Apri19, 2021 by ABC Liovin Drilling (ABC). Soilboringswere advanced to depths ranging from approximately21.5 (HSAboringsB2 through B4)to 51 (HSAboring BI) feetbelow the existing ground surface (bgs), and their approximate locations are shown on the Subsurface Exploration Map, Figure 3. The borings were logged by a Stantec field geologist, who also collected samplesofthe materials encountered forexamination and laboratory testing. 2.3 SAMPLING Relatively undisturbed samples were obtained from the HSA borings using a modified California (CAL) sampler, which is a ring-lined split tube samplerwith a 3-inch outerdiameter and 2'h-inch inner diameter. CAL sampling followed ASTM D3550 (Standard Practice for Ring-Lined Barrel Sampling of Soils)procedures.Disturbed sampleswere obtained using a Standard Penetration Test (SPI) sampler, which is a split tube sampler with a 2-inch outer diameter and 1%-inch inner diameter. SPTs were performed in genera laccordance with AS'IM D1586 (Standard Test Method for Penetration Test and Split-Barrel Sampling of Soils), and D6066 (Standard Practice for Determining the Normalized Penetration Resistance of Sands for Evaluation of Liquefaction Potential). Disturbed bulk samples were also obtained from the drill cuttings and hand auger boring. The CALand SPTsamplerswere driven with a 140-pound weight dropping 30 inches. The number of blows per 6-inch increment is noted on the boring logs. ABC provided a report (Earthspectives, 2020) which indicates the average hammerenergy efficiency on the drillrig used at the project was 64%. Samples were c la ssifie d in the field using the Unified Soil C la ssific a tion System (USC S), in accordance with ASTIV D2488 (Standard Practice forDescription and Identification of Soils[Visual- ManualMethod])procedures. The laboratory testing confirmed ormodified field classifications as necessary for presentation on the boring logs. Soil samples were removed from the samplers, placed in appropriate containers, and transported in accordance with AS'IM D4220 (Standard Practice for Preserving and Transporting Soil Samples). Upon completion, boringswere backfilled ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 2 PRO PO SID HEC AIE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES'IIG ADO N REPO RT Field Investigation April 29,2021 with grout. The boring to g s a rc in c lu d c d in Ap p c n d ix A. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 3 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES'IIG ADO N REPO RT Laboratory Testing Ap ri129,2021 3. IABO RATIO RY TES RNG The following laboratory tests were performed in general accordance with ASIM and California Te st procedures: Table 1. Summary ofLaboratory Tests Type ofTest AS'IMDesignation Number Performed 7 Sieve Analysis ASTVI D422 and ASW C 136 Dire c t Shear AS'IM D3080 2 Maximum Dry Density and Optimum Moisture Content AS'IMD1557 1 (Modified Proctor) ChemicalTests for Corrosion CA DOTte st methods 2 Po to ntia 1 The complete laboratory report is presented in AppendixB. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 4 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT Geologic Setting and Site Conditions April 29,2021 4. G EO LO G IC SETTING AND SITE C O NDMO NS 4.1 REGI0NALGEOLOGY The site islocated in the Peninsular Ranges geologic province which consistsofa series ofranges separated by northwest trending valleys, subparaIlel to faults branching from the San Andreas Fault. 'Ilse Peninsular Ranges extend into lower California and are bound on the east by the Colorado Desert. The Site residesin the portion ofthe Province drained bysurface runofftoward Lake Elsinore located approximately 1.1 milessouthwest ofthe site. Geologic mapping presented in the Geologic Map ofthe Elsinore 7.5' Quadrangle (USGS, 2003) indicates the Site is underlain by Quaternary Young Alluvial Fan (Qyf) deposits and Mesozoic Phyllite (Mzp) deposits. literature from the United States Geologic Survey indicates the alluvialfan depositsinclude unconsolidated deposits consisting ofgravel, sand, and silt. The Phyllite deposits are a type ofinetamorphic rockprimarily composed ofquartzwith white mica and chlorite (USGS, 2003). 4.2 SURFACE CONDMONS The project Site is approximately 1.79 acres in size and isvacant land. The project Site isbound by Cam DelNorte followed byvacantland and Interstate 15to the westand southwest,vacant land and a warehouse building to the north, and vacant land to the east. The Site isgenerally flat with a slope in the southern portion ofthe site thatextendsdown from east to west. Generally, the site slopes downward from northeast to southwest. Based on Google Earth®,the ground surface ofthe Site isatan approximate elevation of1,295to 1,320feet(WGS84 Da turn). 4.3 SUBSURFACE C O NDMO N S The materials encountered in ourborings consist of Quaternary Young AlluvialFan (Qyf) deposits and Mesozoic Phyllite (Mzp) deposits. Abrief description ofthe subsurface conditions is provided in this section. Detailed descriptions of the subsurface conditions are provided in the boring logs included in Appendix A. Adescription ofthe mapped soil units is provided below. Quaternary Young Alluvial Fan (Oyfl Deposits — Holocene age young alluvial fan deposits were encountered in the upper 7 to 13 feet in the northwestern (Boring B2) and southern (Boring B4) portions ofthe site and primarily consist ofsand with variable amounts ofsilt and gravel(SM USCS soiltype) and silt (MLUSCS soiltype) to the maximum depth of exploration. 'Ilse sandy deposits encountered were medium to verydense and generallydry. 'Ilse silty deposits encountered were very stiffto hard and generally dry. ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 5 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G E:O'IEC HNIC AL INVES'IIG ADO N REPO RT Geologic Setting and Site Conditions April 29,2021 Cretaceous Phyllite (Mzj) (Mesozoic) Deposits — Cretaceous age phyllite deposits were encountered throughout most of the site and primarily consist of metamorphic rock known as phyllite, which is primarily composed of quartz, mica, and chlorite. 'Ilse bedrock deposits were medium hard to hard, highly fractured, and highly weathered. Groundwater - Groundwater was encountered at a depth of approximately 35 feet bgs during this investigation. Based on available well data from a groundwater production well approximately 2.4 miles southeast ofthe site,the depth to groundwateratthe site isapproximately 95 feet below the ground surface (bgs) (DWR, 2020). Groundwaterin the site vicinity appears to flow to the southwest toward Lake Elsinore. Groundwater levels may fluctuate in the future due to rainfall, irrigation,broken pipes, orchangesin site drainage. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 6 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES1IG ADO N REPO RT Geologic Hazards Ap r1129,2021 5. G EO LO G IC HAZARDS 5.1 FAULTING AND SURFAC E FAULT RUPTURE Asin most parts of California,the Site islocated in seismically active area. The estimated closest distance from the Site to majornearby mapped active faults is presented in the table below. The estimated distance ofthe Site to the nearest expected surface expression of an active fault is presented in the table below. The distance measurement was taken from a location in the middle ofthe substation, which has a latitude of33.922762°, and a longitude of-116.873552°. Table 2. Faults in Site Vicinity Distance Maximum Moment Fault miles (1) Magnitude (1) Elsin o re 1.4 7.9 Chino 16.8 6.7 San Jacinto 19.0 7.9 San Joaquin Hills 20.8 7.1 Newport—In lewood offshore 28.4 7.0 Newport—In lewood connected 28.4 7.5 San Andreas 31.9 8.2 ]Measured from 2008 National Seismic Hazard Maps—Source Parameters Web site -USGS(USGS,2008). The Site isnotlocated within a currentlymapped Alquist-Priolo Special Studies Fault Zone (CDMG, 2002b). Asnoted above,the nearestactive fauhisthe San Andreas fault, located approximately 1.4 miles southwest ofthe Site. No active faults are known to underlie orproject toward the site. 1herefore,the probabihtyofsurface faultrupture atthe site from a known active fauhisconsidered low. 5.2 C AIIFO RNIA BUILDING CODE SEISMIC CRITERIA Ageologic hazard lhcelyto affectthe project isground-shaking asa result of movement along an active fault zone in the vicinity ofthe Site. 'Ilse seismic parameters in accordance with the 2019 California Building Code (CBC) are presented below: Table 3. 2019 CBC Seismic Parameters and Peak Ground Acceleration Parameter Value Site Coordinates Latitude : 33.6830250 Longitude : -117.328189° Mapped Spectra lAc c eleration Value at Short Period: SS 1.988 Mapped Spectra lAc c elera tion Value at 1-Second Period: S1 0.716 Se ism is Site C la ssific a do n C Short Period Site Coefficient: Fa 1.2 1-Second Period Site Coefficient: Fv 1.4 ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 7 PROPOSED HEC A'IE O R'IEG A BESS AND SUBSTATION G E:O'IEC HNIC AL INVES1IG A1IO N REPO RT Geologic Hazards April 29,2021 Table 3. 2019 CBC Seismic Parameters and Peak Ground Acceleration Parameter Value Site ClassAd'usted Acceleration Value at Short Period: SMs 2.386 Site ClassAd' sted Acceleration Value at 1-Second Period: SMi 1.002 De sig n Sp e c tra I Re sp onse Acceleration at Short Periods: SDs 1.591 Design Spec tru lRe s onse Acceleration at 1-Second Period: SD1 0.668 Peak Ground Acceleration adjusted for Site Class Effects:PGAM 0.849g ASCE7-16—Report generated through ASCE7 Hazards Report web site (ASCE,2019)—accessed 4/29/21. 5.3 UQ UEFAC TIO N AND DYNAMIC SFrREMENT Liquefaction is the transformation of deposit of soil from a solid state to a liquefied state as a consequence of increased pore pressure and reduced effective stress. Often, this transformation resultsfrom the cyclic loading of an earthquake and the soila c quire s"mob ility"sufficient to permit both horizontaland verticalmovements. Soils that are most susceptible to liquefaction are clean, loose, saturated (below groundwater), and uniformly graded sands. 'Ilse vast majority of liquefaction hazards are associated with sandy soils and silty soils of low plasticity. Cohesive soils with a plasticity index (PI) greater than 7 are generally not considered susceptible to soil liquefaction, although they can be subject to cyclic softening if they are soft enough, and if the seismic demand is relatively high. The Site is not located in a California G e o to g is a 1 Survey Iiq u e fa c do n Ha za rd Zone. This zone is defined as areas where historical occurrence of liquefaction, or localgeological, geotechnical and groundwaterconditions indicate a potentialforpermanent ground displacements such that mitigation would be required. The liquefaction potential and dynamic settlement were evaluated with the LigSVs computer program (Geologismiki, 2018) using the SPTdata. Liquefaction triggering methods developed by Idrissand Boulanger(2014) were used in our liquefaction evaluation. Our evaluation was based on the site class adjusted peak ground acceleration of 0.93g, as presented in Table 2, and an earthquake magnitude of 6.25, the modal earthquake magnitude from the 2014 USGS deaggregation website. The in-situ groundwater level of 35 feet bgs was used to evaluate the cyclic resistance ratio of the on-site soil, and the historical high groundwater depth of approximately 30 feet wasused to evaluate the cyclic stressratio forthe design earthquake. Medium dense to very dense granular soil followed by medium hard to hard bedrock soil is generallypresent from the ground surface to a depth ofat least 51.5 feet atthe site. Based on the depth of groundwater table, most of this granular soil in the top 50 feet is not considered susceptible to liquefaction. However, some ofthe unsaturated, medium dense sand in the upper 50feetmaydensifyasa result of earthquake shaking,causing ground surface settlement. Ground surface tota I settlements due to compression in the unsaturated zone are estimated to be on the orderof0.l inches. Differentia lsettlementovera span ofapproximately 30 feet isestimated to be approximately 0.05 inches. ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 8 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT Geologic Hazards April 29,2021 5.4 LIQUEFACTION-INDUC ID LATERAL SPREADING liquefaction induced lateral spreading can occurin areas of sloping ground, ortowardsa free face. Given the relatively flat topography, distance to a free face, and depth to groundwater, the potentialforliquefaction-induced lateralspreading isconsidered low. 5.5 FLO O DING, TSUNAMIS AND SEIC HES The Site islocated within a FEMAFlood Zone Xwhich isan area ofminimalflood hazard (FEMA,2008). Therefore, damage due to flooding is considered low. The Site is not located within a Tsunami Inundation Area; therefore, damage due to tsunamis is considered low. 5.6 EXPANSIVE SOILS The near-surface soils (upper approximate 10 feet) have a low expansion potential Our soil classificationsand laboratoryte stre sults show that the nearsurface (upper 10 feet)sampleste sted are granularwith low-plasticity fines. Accordingly, mitigation forexpansive soils is not considered necessaryforonsite soilsatthisSite. Ifimported soilsare used forearthwork, Stantec recommends that the proposed soilsbe tested for expansion potential prior to import. hnported soils should be approved by the Geotechnical Engineerbefore being imported. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 9 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G E:O'IEC HNIC AL INVES1IG ADO N REPO RT C o n c lesions April 29,2021 6. CONCLUSIONS Based on ourfield exploration, laboratory testing and engineering and geologic analyses, it is our opinion that the Site is suitable fore onstruction ofthe proposed BESSand substation improvements from a geotechnicalengineering and engineering geology viewpoint;however,there are existing geotechnical conditions associated with the Site that warrant mitigation and/or consideration during the planning stages. Me main geotechnical conclusions forthe project are presented in the following paragraphs. • Holocene age young alluvialfan depositswere encountered in the upper? to 13 feet in the northwestern (Boring B2) and southern (Boring B4) portions of the site and primarily consist of sand with variable amounts of silt and gravel (SM USCS soil type) and silt (MLUSCS soiltype) to the maximum depth of exploration. The sandy deposits encountered were medium to very dense and generally dry. 'Ilse silty deposits encountered were verystiffto hard and generally dry. • Bedrock consisting ofcretaceousage phyllite depositswere encountered throughout most ofthe site and primarily consist ofinetamorphic rockknown asphyllite, which is primarily composed of quartz,mica,and chlorite. The bedrock deposits were medium hard to hard, highly fractured, and highly weathered. This material may have an impact on site grading. • Groundwaterwas not encountered during this investigation to a maximum depth of approximately 51 feet. Based on available welldata from a groundwater production wellapproximately2.4 miles southeast of the site,the depth to groundwateratthe site is approximately 95 feet below the ground surface (bgs) (DWR, 2020). Groundwaterin the site vicinity appears to flow to the southwest toward Lake Elsinore. Groundwater levelsmay fluctuate in the future due to rainfall, irrigation, broken pipes, orchanges in site d ra in a g e. • Some sandy layersbetween the ground surface and a depth of approximately 30 feet are potentia fly susceptible to seismically induced settlement.1he potentialtota Ise ismic settlement ofthese layersresulting from a significant seismic event is estimated to be on the orderof0.1 inches. Differential settlements of0.05 inches can be anticipated. 'Ilse estimated totaland differential seismically induced settlements does not exceed typicalfoundation tolerances and therefore willnotrequire mitigation. • A key seismic hazard for the project is ground shaking caused by regionally active faults during a seismic event. 'Ilse structures are likely to experience ground shaking during the irdesign life. GeotechnicaIrecommendationspresented in this report are intended to reduce the seismic risk to an "acceptable level", which means a levelof mitigation tha t p rovid e s re a sona b le protection ofthe public sa fe ty,though Adoesnot ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 10 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT C o n c lesions April 29,2021 necessarily ensure continued structural integrity and functionality of the project (14 C C R 3721 (a)). • No active faults are known to underlie or project toward the site. Therefore, the probability of surface fault rupture occurring at the site from a known active fault is considered low. • 71he Site islocated within a FEMAFIood Zone Nwhich isan area with minimalflood risk (FEMA, 2008). Therefore, damage due to flooding is considered low. ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 11 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT Recommendations Ap ri129,2021 7. REC O MMENDAMO NS 7.1 EAR ITWO RK The following recommendations are provided regarding specific aspects of the proposed earthwork construction. these recommendations should be considered subjectto revision based on Site layout, foundation loads, and additional geotechnical evaluation of the conditions observed by the Ge otec hnic a lEngine er during grading operations. 7.1.1 Site Pre p a ra do n Site preparation should begin with the removal of existing buried slabs and foundations, vegetation, highly organic soil, leach lines, septic tanks, and any other unsuitable materials, if found during grading. Existing underground utilitie s within the proposed construction areas, if any, should be completely removed and/or rerouted. Grading should conform to the guidelines presented in the 2019 Cahfomia Building Code (CBC, 2019), as wellas the pertinent requirements ofthe City oflake Elsinore and Riverside County. 7.1.2 Remedial Grading Shallow Foundation Areas: Existing soils should be excavated to a minimum depth o f 3 feet be low the bottom ofthe footings. The surface exposed by excavation should be scarified to a depth of 8 inches, moisture conditioned to within 3 percentage points ofthe optimum moisture content and compacted to 90 percent relative compaction based on the ASWD1557procedure. Allreferencesto optimum moisture content and relative compaction are based on this test method. Removal and replacement with compacted fillshould extend at least three feet beyond the outside edge of the foundations. The removed soils can be placed backin the excavation as compacted fill. The materialshould be replaced in 8-inch thick loose lifts, moisture conditioned to within 3 percentage points of optimum, and compacted to 90% relative compaction. Excavation, replacement, and compaction beneath shallow foundations should extend horizontally at least two feetbeyond the outside edge ofthe footing areasunless constrained bypropertylines. Concrete Pavement and Hardscape: Remedialgrading forpavementand hardscape areasshould include removalofthe existing soils to a depth of at least 12 inches below the existing ground surface or subgrade elevation, whicheveris deeper. Subgrade elevation is defined asthe top of soilelevation provided in the grading plan. The soilexposed atthe base ofthe excavation should be scarified to a depth of8 inches,and moisture conditioned to within 3 percentage pointsofthe optimum moisture content. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 12 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS1IG ADO N REPO RT Recommendations Ap ri129,2021 Hardscape subgrade should be compacted to at least 90% relative compaction. Pavement subgrade should be compacted to at least 90%relative compaction. Field Observations: The Geotechnical Engineer should checkthe bottom of excavations. Ifsoft, loose, orotherwise unsuitable soilsare encountered, the depth ofremovalmayneed to be extended. 7.1.3 Fill Placement and Compaction Excavated materials determined by the GeotechnicalEngineerto be satisfactory can be reused ascompacted fill. We anticipate thatthe majorityofthe excavated materials can be re-used as compacted fill soils. The Geotechnical Engineer should approve the fill material before placement. Where large compaction equipment is used, such as sheep's foot or smooth drum compactors, fill should be placed in 6- to 8-inch thick loose, horizontal lifts, moisture conditioned to within 3 percentage points of the optimum moisture content and compacted to at least 90% relative compaction. Thinner lifts willbe required for smaller compaction equipment. The maximum dry density and optimum moisture content for the evaluation of relative compaction should be determined in accordance with ASTN4 D1557. 7.1.4 Yielding Subgrade Conditions The soilencountered at the bottom ofthe remedialgrading excavations can exhibit "pumping" oryielding if they become saturated in response to periods of significant precipitation, such as during the winter rainy season. If this occurs, corrective measures should be performed with oversight from the GeotechnicalEngineer. In orderto help stabilize the yielding subgrade soils within the bottom of the removal areas, the contractorcan considerthe placement of stabilization fabric orgeo-grid overthe yielding areas, depending on the relative severity ofthe yielding. Mirafi 60OX (or approved equivalent) stabilization fabric may be used for areas with low to moderate yielding conditions. Geo-grid such asTensarlXS maybe used forareaswith moderate to severe yielding conditions. Uniform sized, 3/4-to 2-inch crushed rockshould be placed overthe stabilization fabric or geo-grid. A 6- to 12-inch thick section of crushed rock will typically be necessary to stabilize yielding ground. If significant voids are present in the crushed gravel, a filter fabric should be placed over the crushed gravelto prevent migration of fines into the graveland thus potential settlement of the overlying fill. Fill soils, which should be placed and compacted in accordance with the recommendations presented herein, should then be placed over the fabric or geo-grid until ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 13 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES'IIG ADO N REPO RT Recommendations Ap ri129,2021 design grades are reached. The crushed graveland stabilization fabric orgco-grid should extend at least 5 feet laterally beyond the limits of the yielding areas. 7.1 .5 De w a to ring Groundwater was encountered at a depth of approximately 35 feet during our investigation. Based on the anticipated foundation and remedialgrading depths, we do not anticipate that groundwaterwillbe a significant consideration forthisproject. 7.1.6 Fxpansive Soil The near-surface soils (approximately upper 10 feet) have a low expansion potential. Our soil classificationsand laboratory te stre sults show that the nearsurface (upperl0feet) samplestested are granularwith low-plasticity fines. Accordingly, mitigation forexpansive soils is not considered necessary at this Site. 'Ilse grading and foundation recommendations presented in this report reflect a low expansion potential. 7.1.7 Imported Material Imported materials, if used for fill, should be predominately granular, contain no rocks or lumps greater than 3 inches in maximum dimension, and have an Expansion Index lessthan 20, and a Plasticity Index less than 15. Imported materials should be reviewed and approved by the Ge otechnic a lEngine erbe fore being brought to the Site. 7.1.8 Site Fxc a va do n Characteristics During the recent geotechnical investigation, the soil boreholes were drilled using a truck- mounted, hollow stem auger drill rig. As the drilling was completed with moderate effort, conventional earth moving equipment should be capable of performing the excavations required forsite development. 7.1.9 Oversized Ma to ria 1 Excavations may generate oversized material. Oversized materia lis defined asrocksorcemented clastsgreaterthan 3 inchesin largest dimension. Oversized materialshould be broken down to no greaterthan 3 inches in largest dimension foruse in fillorbe removed from the Site. 7.1.10 Temporary Fxcavations The existing native soils can be considered Type Bforexcavation in accordance with OSHA and Cal-OSHA requirements. Temporary excavations should be shored orexcavated with a slope not steeperthan 1:1 (horizontalto vertical) in accordance with OSHAand CalOSHArequirements. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 14 PRO PO SID HEC ATE O RIEG A BESS AND SUBSTATION G EO lEC HNIC AL INVFSIIG A71O N REPO RT Recommendations Ap ri129,2021 The excavations should be inspected daily by the contractor's Competent Person before personnelare allowed to enterthe excavation. Any zones of potential instability, sloughing or raveling should be brought to the attention ofthe GeotechnicalEngineer and corrective action implemented before personnelbegin working in the excavation. Excavated soils should not be stockpiled behind temporary excavationswithin a distance equalto the depth ofthe excavation. The project geotechnicalengineershould be notified if other surcharge loads are anticipated so that lateralload criteria can be developed forthe specific situation. If temporary slopes are to be maintained during the rainy season, berms are recommended near the tops of slopes to prevent runoffwaterfrom entering the excavation and eroding the slope faces. 7.1.11 Pipelines Typicalpipe bedding as specified in the Standard Specifications for Public Works Construction (GREENBOOI) may be used. As a minimum, it is recommended that pipe be supported on at least 4 inches of granularbedding material, such as 3/4-inch rock orclean coarse sand with less than 5 percent fines and a sand equivalent of40 ormore as evaluated by ASW D2419. The bedding should extend from the bottom ofthe trench to at least 1 foot above the top ofthe pipe. Sand bedding should be mechanically compacted to at least 90 percent relative compaction. Jetting of sand bedding should not be permitted. Onsite material, imported select material, or2-sackcement/sand slurry maybe used asbackfillin trenches above the pipe bedding. 'Ilse material selected should match the engineering characteristics ofthe soils adjacent to the trench. Utility trench backfillbeneath structures and hardscape should be compacted to at least90%relative compaction. 'Ilse modulus ofsoilreaction (E') is used to characterize the stiffness of soilbackfillplaced along the sides of buried flexible pipelines. For the purpose of evaluating deflection due to the load associated with trench backfilloverthe pipe, a value of 1,500 pounds per square inch (lbs/in2) is recommended for the general site conditions assuming granular bedding material (sand or gravel) is placed around the pipe. 7.1.12 Surface Dra ina g e Final surface grades around structures should be designed to collect and direct surface water away from the structure and toward appropriate drainage facilities. The ground around the structure should be graded so that surface water flows rapidly away from the structure without ponding. In general, we recommend that the ground adjacent to the structure slope away at a gradient of at least 2%. Densely vegetated areas where runoffcan be impaired should have a minimum gradient of at least 5% within the first 5 feet from the structure. Roof gutters with downspouts that discharge directly into a closed drainage system are recommended on structures. Drainage patterns established at the time of fine grading should be maintained ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 15 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT Recommendations Ap ri129,2021 throughout the life of the proposed structures. Site irrigation should be limited to the minimum necessary to sustain landscape growth. Should excessive irrigation, impaired drainage, or unusually high rainfall occur, saturated zones of perched groundwater can develop. Saturated soilzonesmay result in increased maintenance and could impact structure stability. 7.1.13 Grading Plan Re vie w Stantec should review the grading plans and earthwork specifications to ascertain whetherthe intent of the recommendations contained in this report have been implemented, and that no revised recommendations are needed due to changesin the development scheme. 7.2 FOUNDA'HONS 7.2.1 Shallow Foundations An allowable bearing pressure of2,500poundspersquare foot (psf)maybe used forconventional square or rectangular shallow foundations founded in properly compacted fill prepared in accordance withthe recommendations ofthisreport. The bearing capacitycanbe increased by one third for transient loading conditionssuch asearthquake and wind. Additiona 1parameters for sha flow foundationsare provided below. Minimum Footing Width: 18 inches for c ontinuous footings 24 inches for square/rectangular footings Minimum Footing Depth: 18 inchesbelow lowest adjacent soilgrade Minimum Reinforcement: Two No. 5 bars at both top and bottom in continuous footings. Fa rigid mat foundation is required, the mat slab should extend at least 12 inches below the adjacentground surface. The mat thickness should be determined bythe structuralengineer. The mat can be designed assuming an allowable bearing pressure of2,500 pounds persquare foot for dead plus live loads, with a one-third increase for all loads including wind or se ism is. This allowable bearing pressure is a net value;therefore, the weight ofthe mat can be neglected for design purposes. 'Ilse mat should be integrally connected to allportions of the structure, so the entire foundation system movesasa unit. The mat should be reinforced with top and bottom steel in both directionsto allow the foundation to span loc alirregularities that mayresult from potential differentia lsettlement. As a minimum, we recommend that the mat be reinforced with sufficient top and bottom steelto span as a simple beam an unsupported distance of at least 10 feet. The mat can be designed using a modulus ofsubgrade reaction, Kvl, of250 poundspercubic inch. 'Ilse actualmodulus ofsubgrade reaction would need to be adjusted forthe plan dimensions of the mat. ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 16 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES'IIG ADO N REPO RT Recommendations Ap ri129,2021 7.2.2 Drilled Pie r Fo u n d a do n s Drilled piercolumn footingsconsistofreinforced concrete drilled piershaving a minimum diameter orwidth of2.0 feet and embedded a minimum depth of7 feetbgs. Based on these assumptions and the anticipated subsurface conditions, an allowable bearing pressure of4,000psfmay be used in the design. Forresistance to transient lateral loads, such as earthquake and wind loads, the aforementioned allowable bearing capacitymaybe increased byone-third. 7.2.3 Foundation Settlement The following static and seismic foundation settlements are estimated. Static and Seismic Settlement: Lessthan 1-inch totalsettlement 1/2 inch differentia lsettlement over30 feet 7.2.4 IateraIResistance Lateralloadswillbe resisted by friction between the bottoms of footings and passive pressure on the faces of footings and other structural elements below grade. An allowable coefficient of friction of0.35 can be used. Passive pressure can be computed using an equivalent fluid pressure of375 Ibs/ft3 forlevelground conditions. Active pressure can be computed using an equivalent fluid pressure of35 lbs/ft3 for levelground conditions. Reductions for sloping ground should be made. The upper 1 foot of soil should notbe relied on foractive orpassive support unless the ground iscovered with pavements o r sla b s. These pressures are based on levelground conditions in front and behind the foundation with no surcharge loadswithin 10feet. The earth pressuresindicated above do notinclude a safetyfactor; therefore, the design should include an appropriate safety factorforthe overallperformance of the system. 7.2.5 Foundation Plan Review Stantec should review the foundation plans to ascertain that the intent ofthe recommendations in this report has been implemented and that revised recommendations are not necessary as a result of changes afterthis report was completed. 7.2.6 Foundation Excavation Observations Arepresentative working under direct supervision of the Geotechnical Engineer should observe the foundation excavationspriorto forming orplacing reinforcing steel. ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 17 PRO PO SID HEC AIE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT Recommendations Ap ri129,2021 7.3 CORROSION PO UNTIAL Two samples of the onsite soils were tested to provide a preliminary indication of the corrosion potentialof the onsite soils. The test results are presented in Appendix B. A brief discussion of the corrosion test results isprovided in the following text. • The samples tested had a soluble sulfate concentration ranging from 40 to 345 parts permillion (ppm), which indicates the samples have a low sulfate corrosion potential relative to concrete. It should be noted that soluble sulfate in the irrigation water supply, and/orthe use offertilizermay cause the sulfate content in the surficial soils to increase with time. 71his may result in a highersulfate exposure than that indicated by the test resultsreported herein. Studieshave shown that the use ofimproved cements in the concrete, and a low water-cement ratio will improve the resistance of the concrete to sulfate exposure. • The samples tested had a chloride concentration ranging from 23 ppm to 35 ppm, which indicates the sample has a negligible chloride corrosion potential relative to metal. • The samples tested had a saturated resistivity ranging from 1,378 to 2,408 ohm-cm, which indicatesthe samplesare severely corrosive. • lie sample tested had a pHranging from 7.6to 7.7, which indicates the samples are slig htly a lka line. Caltrans currently considers a site to be corrosive to foundation elements if one or more of the following conditions exist: Chloride concentration is greater than or equal to 500 ppm, sulfate concentration is greaterthan orequalto 1,500 ppm, orthe pHis 5.5 orless(Caltrans, 2012). Proposed import fillmaterials should be tested to evaluate theircorrosion potentialpriorto being imported to the site. 7.4 PRELIMINARY PAVEMENTDESIGN 7.4.1 Asphalt Concrete Pavement Tentative driveway structural sections were developed based on the visual onsite soil classifications and an estimate of the anticipated traffic loading. 'Ihe design below applies to driveway sections supported by the existing onsite soils. An Rvalue of30 hasbeen assumed forpreliminary design of pavement sections based on one laboratory test ofthe on-site materialin the uppers feet. The actuaIRvalue ofthe subgrade soils should be determined aftergrading to provide finalpavement design.Flexible pavement sections have been calculated in generalconformance with Caltrans guide fines.The project civilengineer ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 18 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES'IIG ADO N REPO RT Recommendations Ap ri129,2021 and owner should review the pavement designations to determine appropriate locations for pavement thickness. Based on an assumed Rvalue of 30, the following pavement structural sections have been calculated. Table 4. Flexible Pavement Sections Asphalt Concrete Aggregate Base* Traffic Type Traffic Index (inches) (inches) Automobile Parking 5.0 3 5.5 Automobile Drive Lanes 5.5 3 7 Medium Truck Tra ffic 6.0 4 6 Heavy Truck Tra ffic 7.0 4.5 8 *Aggregate Base should conform to Class2 Aggregate Base in accordance with the Caltrans Standard Specifications or Crushed Miscellaneous Base in accordance with the Standard Specifications for Public Works Construction. Prior to placing base materials, the upper 12 inches of the subgrade soil should be scarified, moisture conditioned to slightlyabove the optimum moisture content, and recompacted to a dry densityofat least 95%ofthe laboratory maximum. The base materialshould also be compacted to slightlyabove the optimum moisture contentand a dry density of at least95%ofthe laboratory maximum. Asphalt concrete should be compacted to at least 95% of the laboratory Hveem densityinaccordance withASTMD2726. Rigid concrete pavement (described below) should be placed in driveway entrance apronsand trash bin loading/storage areas. Concrete pavement design isprovided in the following section. 7.4.2 Concrete Pavement Concrete pavements have been calculated in general conformance with the procedure recommended bythe American Concrete Institute (ACI33OR08)using the parameterspresented in Table 5. The following design parameters were used in ouranalyses. Table 5. Concrete Pavement Parameters Design Parameter Value ow Modulus ofSubgrade Reaction (k) 50pci Modulus of Concrete Rupture (MR) 550 psi Concrete Compressive Strength 3,700psi Traffic Categories(IC) Aand C Ave ra g e Da fly Truc k Tra ffic (ADTI) 10 and 100 ® Stantec £v:\1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_sub station geotech_rpt_20210429.docx 19 PRO PO SID HEC ATE O RIEG A BESS AND SUBSTATION G EO TEC HNIC AL INVFSTIG ATIO N REPO RT Recommendations Ap ri129,2021 Based on the parameters above, we recommend the following minimum concrete pavement thic kne ss. Table 6. Recommended Concrete Pavement Sections Traffic Type Pavement'Ihickness (inches) Aggregate Base (inches) Automobile Parking and Driveways 6 6 TC =A Heavy Truck Traffic and Fire Ia n e 8 6 Are a s(TC = C) 'Ilse project civil engineer should confirm whether the assumed ADTT is appropriate for the anticipated traffic level. Concrete compressive strength forpavement should be at least 3,700 psi Minimum reinforcement should consist of #3 bars on 24-inch centers. Crack control joints should be placed in accordance with the American Concrete Institute (ACI) guidelines. Priorto placing concrete, the upper 12 inches of the subgrade soilshould be scarified, moisture conditioned to slightly above the optimum moisture content, and recompacted to a dry density ofat least 95%ofthe laboratory maximum. 7.5 PO ST INVESTIIG ATIIO N SERVICES Post investigation services are an important and necessary continuation of this investigation, and it is recommended that Stantec be retained as the Geotechnical Engineer to perform such services. Finalproject grading and foundation plans,foundation detailsand specifications should be reviewed by Stantec priorto construction to ascertain thatthe intent ofthe recommendations presented herein have been applied to the design. Following review ofplansand specifications, observation during construction should be performed to correlate the findings ofthis exploration with the actualsubsurface conditions exposed. ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 20 PRO PO SID HEC A'IE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVES1IG ADO N REPO RT C to sure Ap ri129,2021 8. C LO SURE Our conclusions, recommendations, and discussions presented herein are based upon an evaluation and interpretation of the findings from the field and laboratory programs, with interpolation and extrapolation of subsurface conditions between and beyond the exploration locations. This report contains information that is valid as of the report's date and to the extent directly known to Stantec. However, conditions can change with the passage of time or construction subsequent to this report's preparation that may invalidate, eitherpartiallyorwholly, the conclusionsand recommendations presented herein. Inherent in most projects performed in the heterogeneous subsurface environment, continuing subsurface explorations and analyses may reveal conditions that are different than those described in this report. The findings and recommendations contained in this report were developed in accordance with generally accepted, current professionalprinciples and practice ordinarily exercised, under similar circumstances, by geotechnical engineers and engineering geologists practicing inthislocality.No otherwarranty, express orimplied, is made. ® Stantec £vA1858\active\185805133\05_report_deliv\deliverable\reports\hecate_ortega_bess_substation geotech_rpt_20210429.docx 21 PROPOSED HEC AIE O RIEG A BESS AND SUBSTATION G EO'IEC HNIC AL INVFS'IIG ADO N REPO RT References Ap ri129,2021 9. REFERENC ES American Society fo r Te sting and Ma to ria is(ASTIA), 2008,Annua 1 Bo o k o f ASTVI Standards,Vo lum e 04.08, Construction: Soil and Rock(I), Standards 420 -D 5876. American Society of Civil Engineers (ASCE), 2016, Minimum Design Dads for Buildings and Other Struc ture s, ASC E Do c um e nt ASC F/SEI 7-16. ASCEHazard ToolWebsite,ASCE7HazardsReport,https://a see 7hazardtool.onhne,accessed April 28, 2021. California Building Code, 2019, Chapters 16 and 18. California Geologic aISurvey (CGS), 2008,http://www.consrv.ca.gov/cas. California Department of Conservation, Division of Mines and Geology (CDMG), 2003, Digital hnagesofOfficialMapsofAlquist-Priolo Earthquake FaultZanesofCalifomia. California Division of Mines and Geology (CDMG), 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special Publication 117, adopted March 13, 1997, revised and re-adopted September 11, 2008. California Department of Water Resources (DWR), September 22, 2020, Groundwater Level Report, Station 336555N1173035W002. California Department of Transportation (Caltrans), March 7, 2014, Highway Design Manual, Chapters 630 and 850. Caltrans,November2012, Corrosion Guidelines,Version 2.0. Caltrans, 2010, Memo to Designers 10-5, Protection of Reinforcement against Corrosion Due to Chlorides,Acids and Sulfates. California Office of Emergency Services,http://myhazards.caloes.ca.gov/ accessed April28, 2021. EarthSpectives,December28, 2020, SPTHammerEnergy Measurement, Drill Rigs R-1 (CME-85), R 5 (CME-85), a nd R 9 (CME-75), ES Project No. 190806-365. Federal Emergency Management Act, August 28, 2008, FEMA Flood Map Service Center, Map No. 06065C2037G, https://msc.fema.gov/portal, accessed April29, 2021. Google Earth®, 2018,Version 7.3.2.5776 Martin, G., Lew, M., Arulmoli, K, Baez, J., Blake, T., Earnest, J., Gharib, F., Goldhammer, J., Hsu, D., Kupferman, S., O'Tousa, J., Real, C., Reeder, W., Simantob, A., & Youd, T. (1999). Recommended Procedures for Implementation of DMG Special Publication 117 ® Stantec fjv:\1858\active\185805133\05_report_daliv\deliverable\reports\hecato_ortega_bass_substation geotoch_rpt_20210429.docx 22 PROPOSED HEC A'IE O RIEG A BESS AND SUBSTATION G E:O'IEC HNIC AL INVES'IIG ADO N REPO RT References April 29,2021 Guidelines for Analyzing and Mitigating Liquefaction Ha za rd in Ca lifo rn is. Los An g e le s, USA: 'Ihe Southern California Earthquake Center. Southern California Earthquake Center (SCEC) (1999), Recommended Procedures for Implementation ofDMG SpecialPublication 117, Guidelines for Analyzing and Mitigating Iiq u e fa c do n Ha za rd s in C a lifo rn is, Un ive rsity o f Southern C a lifo m is,p. 60. United States Geological Survey(USGS), 2008 NationalSeismic Hazard Maps—Source Parameters Website - https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query main.cftn, accessed Ap ri129, 2021. USGS, 2003, Preliminary Geologic Map ofthe Elsinore 7.5' Quadrangle, Scale 1:24,000 USGS, 1997, Iake Elsinore, California Quadrangle, 7.5 Minute Series(topographic), scale 1:24,000. ® Stantec fjv:\1858\active\185805133\05_report_daliv\deliverable\reports\hecato_ortega_bass_substation geotoch_rpt_20210429.docx 23 FIGURES ® Stantec fjv:\1858\active\185805133\05_mport_deliv\deliverable\reports\hecato_ortega_bass_substation geotoch_rpt_20210429.docx 24 X4 30 v JI/ 117 7 IV. r—D V; 36 46 !e If % Me& I z!' w: P ftSITE )1v 6 21, L A K E E L 3 1 N 0 R E 0 S T A T E R E C R E A T 1 0 N A R E A L A K E E L S I N 0 R E Z ON 2 1 0 2 II SCALE IN MILE CALIFORNIA 2000 0 2000 4000 6000 8000 10000 12000 14000 SCALE IN FEET REFERENCE: USGS 7 5 X 15 MINUTE L UADRANGLE LAKE ELSINORE,CA 1997 FOR: FIGURE: ORTEGA BATTERY ENERGY SITE LOCATION MAP stantec STORAGE SYSTEM PROJECT NEAR SEC CAM DEL NORTE&O'HANA CIR LAKE ELSINORE,CALIFORNIA 735 E CARNEGIE DRIVE,SUITE 280 SAN BERNARDINO,CA 92408 JOB NUMBER: DRAWN BY: CHECKED BY: APPROVED BY: DATE: PHONE:(909)335-6116 FAX:(909)335-6120 185805133 JEF JEF JEF 4/27/2021 FILEPATH:V:\1858\active\185805133\ub-repon aenv\arawings aesign\caa ng\necate onega igures MM.awg moamea Dyjtiscner on Apr 7,2021 at 779 •'f • ' �.. ��` ;_ �,'� • •�• 1. • r�•1 `:r° �y � , 'tSt it y~ '•• '. �• - �£ •1 �;�! � •`� i�� 'y� ,.� ; 1 -- _�s��'-`�:ate. \ . ' - •:,�� — _ All _/7 NN ty '' ... �'Vlry` i \ ` , C, sf•• .��. '; / 1,� w1Pl�'y� I Ss .r. I ` -(� ^�`ti � �.�' � `��, i.�` •� _ • 'y •t +.S �, 1,y~,� • . 5 �'L•i � �� ram.;+ t Td.. � - •. .y •J.�i N ® FOR: FIGURE: Stantec ORTEGA BATTERY ENERGY SITE VICINITY MAP EXPLANATION 2 0 200 400 STORAGE SYSTEM PROJECT NEAR SEC CAM DEL NORTE&O'HANA CIR APPROXIMATE PROJECT BOUNDARY LAKE ELSINORE,CALIFORNIA 735 E CARNEGIE DRIVE,SUITE 280 APPROXIMATE SCALE (FEET) SAN BERNARDINO,CA 92408 JOB NUMBER: DRAWN BY: CHECKED BY: APPROVED BY: DATE: PHONE:(909)335-6116 FAX:(909)335-6120 185805133 JEF JEF JEF 4/27/2021 FILEPATH:V:\1858\active\185805133\05_report_deliv\drawings_design\cad_fig\hecate_ortega_figures_042721.dwg modified by jfischer on Apr 27,2021 at 13:00 EXPLANATION APPROXIMATE PROJECT BOUNDARY B4 APPROXIMATE GEOTECHNICAL SOIL BORING LOCATIONS V % '7C.C/ 1 BRIDGE CROSSING � SCE EQUIPM- RESERVE �q. ZZ 'oQ AUX SERVICE _ SWITCH GEAR C - - \ I \ T 40' \\ 2G2 202 - - - - - o� k, \} v � v �i 0�� SCE�POLE 22254755E I L i B4 N ® FOR: FIGURE: ORTEGA BATTERY ENERGY SUBSURFACE EXPLORATION MAP Stantec STORAGE SYSTEM PROJECT 3 0 60 120 NEAR SEC CAM DEL NORTE&O'HANA CIR LAKE ELSINORE,CALIFORNIA 735 E CARNEGIE DRIVE,SUITE 280 SAN BERNARDINO,CA 92408 JOB NUMBER: DRAWN BY: CHECKED BY: APPROVED BY: DATE. APPROXIMATE SCALE(FEET) PHONE:(909)335-6116 FAX:(909)335-6120 185805133 JEF JEF JEF 4/27/2021 FILEPATH:V:\1858\active\185805133\05_report_deliv\drawings_design\cad_fig\hecate_ortega_figures_042721.dwg modified by JFischer on Dec 23,2021 at 11:50 v. ;!�' f ��. 4 \ fir_) ► _ ': - • //19• • r �� /.. Q f7r•�' •�' .. � /f - �'.��• 11 Ir�1� \' •�' ` •• ff - •• r �� ``l�(!- 5 -� ice_ BM 1275 21 �Lj X o i xj ,;' Cam~ -_ �:= { _r �_. 'h•',�,�'�Wd&E;. .lSj7��•3�,' •.�`�.:. . ,, � _�� — `�. 1� ( ,l,r/ (�ti � /� �._ CJ �0�� ti �.. - _ [ V `--`- •SCE -- l � � - ,..� � �� ` r II/ _J `® ■ � / I '( I 1 � f a ..;,, `�tcpO �� ' � r,� iT/C-�M � � �_ •� � �` r • i- y �� . are �I. , �I l Ilk ■ G l j' / rGull f • 7 � , • ■ . ' 4V 907 N ® FOR: FIGURE: EXPLANATION 0 1000 2000 ® Stantec ORTEGA BATTERY ENERGY GEOLOGIC MAP STORAGE SYSTEM PROJECT 2 NEAR SEC CAM DEL NORTE&O'HANA CIR APPROXIMATE PROJECT BOUNDARY �= ® LAKE ELSINORE,CALIFORNIA 735 E CARNEGIE DRIVE,SUITE 280 APPROXIMATE SCALE(FEET) SAN BERNARDINO,CA 92408 JOB NUMBER: DRAWN BY: CHECKED BY: APPROVED BY: DATE: PHONE:(909)335-6116 FAX:(909)335-6120 185805133 JEF JEF JEF 4/27/2021 FILEPATH:V:\1858\active\185805133\05_report_deliv\drawings_design\cad_fig\hecate_ortega_figures_042721.dwg modified by JFischer on May 04,2021 at 11:07 APPENDIX A BORING LOGS UNIFIED SOIL CLASSIFICATION (ASTM D-2487) MATERIAL CRITERIA FOR ASSIGNING SOIL GROUP NAMES GROUP SOIL GROUP NAMES&LEGEND TYPES SYMBOL GRAVELS *CLEAN Cu>4AND 1<Cc<3 GW WELL-GRADED GRAVEL GRAVELS<5% J >50%OF COARSE FINES Cu>4 AND 1>Cc>3 GP POORLY-GRADED GRAVEL O z FRACTION RETAINED U)O LU ON NO4.SIEVE *GRAVELS WITH FINES CLASSIFY ASMLORCL GM SILTY GRAVEL w z LU FINES>12%FINES GC CLAYEY GRAVEL z z LU FINES CLASSIFY AS CL OR CH LU O Cu>6AND 1<Cc<3 SW WELL-GRADED SAND W N SANDS *CLEAN SANDS UJ Z <5%FINES Cu>6AND 1>Cc>3 SP POORLY-GRADED SAND a0 A >50%OF COARSE U FRACTION PASSES FINES CLASSIFYAS ML OR CL SM SILTY SAND ON NO 4.SIEVE *SANDS AND FINES>12%FINES FINES CLASSIFYASCLORCH Sc CLAYEY SAND SILTS AND CLAYS PI>7AND PLOTS>"A"LINE CL LEAN CLAY U) INORGANIC O U)w LIQUID LIMIT<50 PI>4AND PLOTS<"A"LINE ML SILT U)Lu> Lu U)w ORGANIC LL(oven dried)/LL(not dried)<0.75 OL ORGANIC CLAY OR SILT Z_Q U)a0 o N SILTS AND CLAYS PI PLOTS>"A"LINE CH FAT CLAY C7 O INORGANIC A z z LIQUID LIMIT>50 PI PLOTS<"A"LINE MH ELASTIC SILT z LL ORGANIC LL(oven dried)/LL(not dried)<0.75 OH ORGANIC CLAY OR SILT HIGHLY 0 RGANIC SOILS PRIMARILY ORGANIC MATTER,DARK IN COLOR,AND ORGANIC ODOR PT PEAT Dual symbols required for fines content between 5%and 12% SAMPLER TYPES PLASTICITY CHART ® SPT , Shelby Tube 80 70 B Modified California(2.5"I.D.) No Recovery 60 Rock Core ® Grab Sample CH Z 50 ADDITIONAL TESTS 40 COR - CHEMICAL ANALYSIS(CORROSIVITY) PI - PLASTICITY INDEX O CD - CONSOLIDATED DRAINED TRIAXIAL EI - EXPANSION INDEX g 30 CN CONSOLIDATION TC CYCLIC TRIAXIAL o_ CL � OH&MH CU - CONSOLIDATED UNDRAINED TRIAXIAL TV - TORVANE SHEAR 20 .P DS - DIRECTSHEAR UC - UNCONFINED COMPRESSION PP - POCKET PENETROMETER(TSF) (1.5) - (WITH SHEAR STRENGTH 10 #200 - Percent Passing#200 SIEVE IN KSF) - RV - R-VALUE UU - UNCONSOLIDATED 0 UNDRAINED TRIAXIAL 0 10 20 30 40 50 60 70 80 90 100 110 120 SA - SIEVE ANALYSIS:%PASSING LIQUID LIMIT(%) WATER_ LEVEL NUMBER OF BLOWS OF 140 LB HAMMER FALLING 30 INCHES TO DRIVE A2 INCH O.D. PENETRATION RESISTANCE(RECORDEDAS BLOWS/FOOT) (1-3/8 INCH I.D.)SPLIT-BARREL SAMPLER THE LAST 12 INCHES OFAN 18-INCH DRIVE (ASTM-1586 STANDARD PENETRATION TEST). SAND&GRAVEL SILT&CLAY *UNDRAINED SHEAR STRENGTH IN KIPS/SQ.FT.AS DETERMINED BY LABORATORY RELATIVE DENSITY BLOWS/FOOT* CONSISTENCY BLOWS/FOOT* STRENGTH"(KSF) TESTING OR APPROXIMATED BY THE STANDARD PENETRATION TEST,POCKET PENETROMETER,TORVANE,OR VISUAL OBSERVATION. VERYLOOSE 0-4 VERY SOFT 0-2 0-0.25 LOOSE 4-10 SOFT 2-4 0.25-0.5 MEDIUM DENSE 10-30 MEDIUM STIFF 4-8 0.5-1.0 DENSE 30-50 STIFF 8-15 1.0-2.0 VERY DENSE OVER 50 VERY STIFF 15-30 2.0-4.0 HARD OVER 30 OVER 4.0 LEGEND TO BORING LOGS AND SOIL DESCRIPTIONS ® Stantec PROJECT:Hecate Ortega Bllzbs WELL/PROBEHOLE/BOREHOLE NO: LOCATION:Cam Del Norte, Lake Elsinore, California Stantec PROJECT NUMBER:185805133 B-1 PAGE 1 OF 3 DRILLING/INSTALLATION: NORTHING(ft): EASTING(ft): STARTED 4/9/21 COMPLETED: 4/9/21 LAT:330 41' 1.36" LONG:1170 19'39.77" DRILLING COMPANY:ABC Liovin GROUND ELEV(ft):1304 TOC ELEV(ft): INITIAL DTW(ft):35.0 WELL DEPTH(ft): DRILLING EQUIPMENT:CME-85 STATIC DTW(ft):35.0 BOREHOLE DEPTH(ft):51.5 DRILLING METHOD:Hollow Stem Auger WELL CASING DIA. (in):--- BOREHOLE DIA. (in):8 SAMPLING EQUIPMENT:Split Spoon LOGGED BY:K. Grasso CHECKED BY: od U N U °' °' o U Description Time N m 0 3 N o.w Q m E 0�' m cn p co Sample ID °' m Cj m a 3 2 CRETACEOUS PHYLLITE(MESOZOIC)(MzP)DEPOSITS Metamophic rock, phyllite,gray, hard, highly fractured and weathered, 7:49 SA dry d v B-1-2' 5 5 7:55 IDS 25 B 1-5' 50-5" 15 25 B 1 7' 30 is 10 Medium hard below 10 feet 8.10 35 10 N B-1-10' 50-3" a N m =' N l O O W l Q J d l' LU W �• H O K z F15 Hard below 15 feet 25 15 z 35 N 8:20 50-5" B-1-15' 0 0 J J l' Q LU W 0LU = 20 35 20 8:38 50-3" M l � B-1-20' O w O w O PROJECT:Hecate Ortega BlIz5b WELL/PROBEHOLE/BOREHOLE NO: LOCATION:Cam Del Norte, Lake Elsinore, California Stantec PROJECT NUMBER:185805133 B-1 PAGE 2 OF 3 DRILLING/INSTALLATION: NORTHING(ft): EASTING(ft): STARTED 4/9/21 COMPLETED: 4/9/21 LAT:330 41' 1.36" LONG:1170 19'39.77" DRILLING COMPANY:ABC Liovin GROUND ELEV(ft):1304 TOC ELEV(ft): INITIAL DTW(ft):35.0 WELL DEPTH(ft): DRILLING EQUIPMENT:CME-85 STATIC DTW(ft):35.0 BOREHOLE DEPTH(ft):51.5 DRILLING METHOD:Hollow Stem Auger WELL CASING DIA. (in):--- BOREHOLE DIA. (in):8 SAMPLING EQUIPMENT:Split Spoon LOGGED BY:K. Grasso CHECKED BY: od U °' °' o U Description Time N m 0 3 N o.w Q m E �' m cn p co Sample ID °' m Cj m a 3 2 i 25 25 40 8:50 50-6" B-1-25' 30 30 30 9:03 50 3" B-1-30' 7 l N m =' N l O O LU Q 35 Wet below 35 feet B91�35' 50-4" - 35 LU w H 0 z w U w l' Z Q N ui 0 0 J J Qi 40 9:40 50 6" 40 W B-1-40' of : LU Q _ U ' w l 2 o M l l LL 0 w l PROJECT:Hecate Ortega BLbb WELL/PROBEHOLE/BOREHOLE NO: LOCATION:Cam Del Norte, Lake Elsinore, California Stantec PROJECT NUMBER:185805133 B-1 PAGE 3 OF 3 DRILLING/INSTALLATION: NORTHING(ft): EASTING(ft): STARTED 4/9/21 COMPLETED: 4/9/21 LAT:330 41' 1.36" LONG:1170 19'39.77" DRILLING COMPANY:ABC Liovin GROUND ELEV(ft):1304 TOC ELEV(ft): INITIAL DTW(ft):35.0 WELL DEPTH(ft): DRILLING EQUIPMENT:CME-85 STATIC DTW(ft):35.0 BOREHOLE DEPTH(ft):51.5 DRILLING METHOD:Hollow Stem Auger WELL CASING DIA. (in):--- BOREHOLE DIA. (in):8 SAMPLING EQUIPMENT:Split Spoon LOGGED BY:K. Grasso CHECKED BY: od U °' °' o U Description Time N m 0 3 N o.w Q m E �' m cn p co Sample ID °' m Cj m o 3 2 45 9:56 50 3" 45 B-1-45' 50 50 10:11 B-1-50' Borehole terminated at 51.5 feet. N a 55 55 LU 0 m N O O H J 2 LU 0 z W U F Z H N 60 60 'a ui 0 0 J 0 0 LU 01 LU 0 U LU 0 M 0 65 65 0 W PROJECT:Hecate Ortega ElLbs WELL/PROBEHOLE/BOREHOLE NO: LOCATION:Cam Del Norte, Lake Elsinore, California StanteC PROJECT NUMBER:185805133 B-2 PAGE 1 OF 1 DRILLING/INSTALLATION: NORTHING(ft): EASTING(ft): STARTED 4/9/21 COMPLETED: 4/9/21 LAT:330 41' 1.23" LONG:1170 19'43.02" DRILLING COMPANY:ABC Liovin GROUND ELEV(ft):1302 TOC ELEV(ft): DRILLING EQUIPMENT:CME-85 INITIAL DTW(ft):Not Encountered WELL DEPTH(ft): STATIC DTW(ft):Not Encountered BOREHOLE DEPTH(ft):21.5 DRILLING METHOD:Hollow Stem Auger WELL CASING DIA. (in):--- BOREHOLE DIA. (in):8 SAMPLING EQUIPMENT:Split Spoon LOGGED BY:K. Grasso CHECKED BY: od U o U Description Time N �, 0 3 N o Is Q mE (Dw m cn p co Sample ID °' aoj 2 QUATERNARY VERY YOUNG ALLUVIAL FAN(Qfl DEPOSITS �n MDD, CORR SM SILTY SAND;SM; 10YR 5/3 brown;8%fine gravel;54%fine to 11:00 SA coarse grained sand;38%fines;dry; no petroleum hydrocarbon odor B-2-2' (PHCO);no staining. — —————————————————————————————— 5 SM SILTY SAND WITH GRAVEL;SM; 10YR 5/2 grayish brown; 17%fine 5 gravel;52%fine to coarse grained sand;31%fines;dry;dense;no 17 PHCO;no staining. SA 20 11:05 25 B-2-5' 10YR 6/4 light yellowish brown; 18%fine gravel;46%fine to coarse grained sand;36%fines;very dense below 7 feet 40 SA 38 11:19 45 B-2-7' 10 10YR 4/3 brown;80%fine gravel; 10%fine to coarse grained sand; 10% 10 fines; moist;dense below 10 feet 10 N 12 N 11:28 12 0 B-2-10' c� m 0 N O O W ----------------------------------- Q d W CRETACEOUS PHYLLITE(MESOZOIC)(MzP)DEPOSITS z F15 Metamophic rock, phyllite,gray, hard, highly fractured and weathered, 44 15 Q dry 11:37 50-6„ B-2-15' ui 0 O Qi a w _ K O w Q �. U = 20 20 25 M 11:47 50-6" B-2-20' o ° Borehole terminated at 21.5 feet. LU PROJECT:Hecate Ortega ElLbs WELL/PROBEHOLE/BOREHOLE NO: LOCATION:Cam Del Norte, Lake Elsinore, California Stantec PROJECT NUMBER:185805133 B- PAGE 1 OF 1 DRILLING/INSTALLATION: NORTHING(ft): EASTING(ft): STARTED 4/9/21 COMPLETED: 4/9/21 LAT:330 40' 58.89" LONG:1170 19'41.48" DRILLING COMPANY:ABC Liovin GROUND ELEV(ft):1298 TOC ELEV(ft): DRILLING EQUIPMENT:CME-85 INITIAL DTW(ft):Not Encountered WELL DEPTH(ft): STATIC DTW(ft):Not Encountered BOREHOLE DEPTH(ft):21.5 DRILLING METHOD:Hollow Stem Auger WELL CASING DIA. (in):--- BOREHOLE DIA. (in):8 SAMPLING EQUIPMENT:Split Spoon LOGGED BY:K. Grasso CHECKED BY: od U N U °' °' o U Description Time N m 0 3 N o.w Q m E 0�' m cn p co Sample ID °' m Cj m a 3 2 CRETACEOUS PHYLLITE(MESOZOIC)(MzP)DEPOSITS Metamophic rock, phyllite,gray, hard, highly fractured and weathered, 12:50 SA dry B-3-2' 5 5 40 40 13:00 35 B-3-5' Medium hard below 7 feet 7 g 13:05 9 B-3-7' is 10 10 10 7 N 13:10 10 B-3-10' c� m N l O O W l Q J d l' Uj W �• H O K z LU W 15 Hard below 15 feet 15 z 10 N 17 13:14 20 B-3-15' 0 0 J J l' Q Uj W 01Uj U ' = 20 20 M l_ 22 25 0 13:23 40 B-3-20' ° Borehole terminated at 21.5 feet. 0 PROJECT:Hecate Ortega ElLbs WELL/PROBEHOLE/BOREHOLE NO: LOCATION:Cam Del Norte, Lake Elsinore, California A Stantec PROJECT NUMBER:185805133 B-4 PAGE 1 OF 1 DRILLING/INSTALLATION: NORTHING(ft): EASTING(ft): STARTED 4/9/21 COMPLETED: 4/9/21 LAT:330 40' 56.89" LONG:1170 19'39.48" DRILLING COMPANY:ABC Liovin GROUND ELEV(ft):1305 TOC ELEV(ft): DRILLING EQUIPMENT:CME-85 INITIAL DTW(ft):Not Encountered WELL DEPTH(ft): STATIC DTW(ft):Not Encountered BOREHOLE DEPTH(ft):21.5 DRILLING METHOD:Hollow Stem Auger WELL CASING DIA. (in):--- BOREHOLE DIA. (in):8 SAMPLING EQUIPMENT:Split Spoon LOGGED BY:K. Grasso CHECKED BY: od U o U Description Time N �, 0 3 N o Is Q mE (Dw m cn p co Sample ID °' aoj 2 QUATERNARY VERY YOUNG ALLUVIAL FAN(Qfl DEPOSITS �n CORR SM SILTY SAND;SM; 10YR 4/3 brown; 13%fine gravel;66%fine to 13:45 SA coarse grained sand;21%fines;dry; no petroleum hydrocarbon odor B-4-2' (PHCO);no staining. 5 5%fine gravel;53%fine to coarse grained sand;42%fines;dry; 5 medium dense below 5 feet. 11 SA 13 13:47 15 CRETACEOUS PHYLLITE(MESOZOIC)(MzP)DEPOSITS Metamophic rock, phyllite, brown,hard, highly fractured and weathered, dry 12 IDS 15 13:50 26 B-4-7' 10 Medium hard below 10 feet 10 7 N � 8 N 13:55 9 B-4-10' ta N O l O l W H Q l J d W l H K z Z LU W 15 Hard below 15 feet 15 z z 15 18 14:04 25 B-4-15' 0 o o Qi W of w a U = 20 20 13 22 0 14:15 35 B-4-20' ° Borehole terminated at 21.5 feet. APPENDIX B IABO RATO RY TEST RESULTS Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source Grab Lab ID B1-2' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 416.10 Analysis based on total sample. Moisture Content (%) 3.5 Grams % % % Gravel 48.7 Sieve Size Retained Retained Passing % Sand 27.9 % Fines 23.4 Fines Classification ML D10 (mm) N/A 2" 142.80 34.3 65.7 D30 (mm) N/A 3/4" 18.20 4.4 61.3 D60 (mm) N/A 1/2" 0.00 0.0 61.3 3/8" 11.90 2.9 58.4 Cu N/A No. 4 1 29.60 7.1 51.3 Cc N/A No. 8 37.10 8.9 42.4 No. 16 25.30 6.1 36.3 Classification No. 30 18.90 4.5 31.8 Silty Gravel (GM)with Sand No. 50 16.30 3.9 27.9 No. 100 10.90 2.6 25.3 Classification determined by ASTM D 2487. -200 No. 200 7.60 1.8 23.4 material classification determined by visual assessment, ASTM D 2488. Pan 97.50 23.4 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B1-2.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source Grab Lab ID B2-2' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 232.80 Analysis based on total sample. Moisture Content (%) 5.5 Grams % % % Gravel 7.7 Sieve Size Retained Retained Passing % Sand 54.2 % Fines 38.1 Fines Classification ML D10 (mm) N/A D30 (mm) N/A D60 (mm) N/A Cu N/A No. 4 1 17.90 7.7 92.3 Cc N/A No. 8 23.10 9.9 82.4 No. 16 26.50 11.4 71.0 Classification No. 30 23.90 10.3 60.7 Silty Sand (SM) No. 50 21.00 9.0 51.7 No. 100 16.90 7.3 44.5 Classification determined by ASTM D 2487. -200 No. 200 14.70 6.3 38.1 material classification determined by visual assessment, ASTM D 2488. Pan 88.80 38.1 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B2-2.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source SPT Lab ID B2-5' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 216.00 Analysis based on total sample. Moisture Content (%) 8.8 Grams % % % Gravel 17.1 Sieve Size Retained Retained Passing % Sand 52.2 % Fines 30.7 Fines Classification ML D10 (mm) N/A D30 (mm) N/A D60 (mm) N/A 1/2" 12.50 5.8 94.2 3/8" 7.70 3.6 90.6 Cu N/A No. 4 1 16.70 7.7 82.9 Cc N/A No. 8 25.10 11.6 71.3 No. 16 25.70 11.9 59.4 Classification No. 30 20.40 9.4 50.0 Silty Sand (SM)with Gravel No. 50 17.50 8.1 41.9 NO. 100 13.40 6.2 35.6 Classification determined by ASTM D 2487. -200 No. 200 10.60 4.9 30.7 material classification determined by visual assessment, ASTM D 2488. Pan 66.40 30.7 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B2-5.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source CalMod Lab ID B2-7' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 234.90 Analysis based on total sample. Moisture Content (%) 7.0 Grams % % % Gravel 18.0 Sieve Size Retained Retained Passing % Sand 45.8 % Fines 36.3 Fines Classification ML D10 (mm) N/A D30 (mm) N/A D60 (mm) N/A 3/8" 24.20 10.3 89.7 Cu N/A No. 4 1 18.00 7.7 82.0 Cc N/A No. 8 19.00 8.1 73.9 No. 16 23.30 9.9 64.0 Classification No. 30 18.60 7.9 56.1 Silty Sand (SM)with Gravel No. 50 16.60 7.1 49.0 NO. 100 15.30 6.5 42.5 Classification determined by ASTM D 2487. -200 No. 200 14.70 6.3 36.3 material classification determined by visual assessment, ASTM D 2488. Pan 85.20 36.3 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B2-7.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source Grab Lab ID B3-2' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 239.00 Analysis based on total sample. Moisture Content (%) 6.9 Grams % % % Gravel 7.3 Sieve Size Retained Retained Passing % Sand 55.9 % Fines 36.7 Fines Classification ML D10 (mm) N/A D30 (mm) N/A D60 (mm) N/A Cu N/A No. 4 1 17.50 7.3 92.7 Cc N/A No. 8 26.00 10.9 81.8 No. 16 28.90 12.1 69.7 Classification No. 30 23.30 9.7 60.0 Silty Sand (SM) No. 50 21.40 9.0 51.0 No. 100 17.50 7.3 43.7 Classification determined by ASTM D 2487. -200 No. 200 16.60 6.9 36.7 material classification determined by visual assessment, ASTM D 2488. Pan 87.80 36.7 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 0)40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B3-2.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source Grab Lab ID B4-2' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 235.00 Analysis based on total sample. Moisture Content (%) 7.5 Grams % % % Gravel 13.3 Sieve Size Retained Retained Passing % Sand 65.5 % Fines 21.1 Fines Classification ML D10 (mm) N/A D30 (mm) N/A D60 (mm) N/A Cu N/A No. 4 1 31.30 13.3 86.7 Cc N/A No. 8 35.20 15.0 71.7 No. 16 31.90 13.6 58.1 Classification No. 30 24.70 10.5 47.6 Silty Sand (SM) No. 50 22.30 9.5 38.1 No. 100 20.40 8.7 29.4 Classification determined by ASTM D 2487. -200 No. 200 19.50 8.3 21.1 material classification determined by visual assessment, ASTM D 2488. Pan 49.70 21.1 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 0 40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B4-2.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK Stantec Gradation Analysis ASTM D 422 Project Name Hecate Ortega BESS Project Number 185805133 Source SPT Lab ID B4-5' Date Received 04-22-2021 Preparation Method ASTM D 1140 Method A Preparation Date 04-26-2021 Particle Shape Test Date 04-27-2021 Particle Hardness Sample Dry Mass (g) 288.50 Analysis based on total sample. Moisture Content (%) 8.9 Grams % % % Gravel 5.4 Sieve Size Retained Retained Passing % Sand 52.5 % Fines 42.1 Fines Classification ML D10 (mm) N/A D30 (mm) N/A D60 (mm) N/A Cu N/A No. 4 1 15.70 5.4 94.6 Cc N/A No. 8 24.20 8.4 86.2 No. 16 31.30 10.8 75.3 Classification No. 30 28.00 9.7 65.6 Silty Sand (SM) No. 50 26.00 9.0 56.6 No. 100 22.00 7.6 49.0 Classification determined by ASTM D 2487. -200 No. 200 19.90 6.9 42.1 material classification determined by visual assessment, ASTM D 2488. Pan 121.40 42.1 --- Particle Size Distribution Sieve Size in inches Sieve Size in sieve numbers 100.00 6 3 2 1 3/4 3/8 4 10 16 30 40 100 200 90.00 80.00 70.00 c y 60.00 N a 50.00 c a� 0 40.00 a 30.00 20.00 10.00 0.00 1000 100 10 1 0.1 0.01 0.001 Diameter(mm) Comments Reviewed By File:Hecate_Ortega_BESS_Sieve_B4-5.xlsm Sheet:Report Laboratory Document Preparation Date:1-2008 Prepared By:JW Revision Date:4-2008 Stantec Consulting Services Inc. Approved By:TLK JD & S Testing Direct Shear Moisture Content & Density Project Name: Hecate Ortega BESS Project Number: 185805133 Sampled By: CLIENT Sample Date: 4/9/2021 Lab#: 131-5 Source/Location: B1@5 Tested By: M.P. Description: SW-SM Test Date: 4/29/2021 Shearing Rate(in./min.) 0.040 Normal Pressure(psf) 1000 2000 4000 [A] Initial Weight of Wet Soil+Ring(o.1g) 180.4 187.8 179.5 [B] Weight of Ring(0.1g) 45.6 46.4 46.5 [C]_[A]-[B] Initial Weight of Wet Soil (o.1g) 134.8 141.4 133.0 [D] Initial Reading 0.0000 0.0000 0.0000 [E] Final Reading 0.0184 0.0058 0.0032 [F]_[E]-[D] Height Change 0.0184 0.0058 0.0032 [G]=1-[F] Final Height 0.9816 0.9942 0.9968 Shear Strength(psf) 924 1824 3360 [H] Final Weight of Wet Soil (0.1g) 144.1 152.1 141.0 [J] Weight of Dry Soil(o.1g) 126.3 133.4 124.8 [K] Specific Gravity [L] Average Maximum Dry Density(o.lpcf) 106.6 [M] Initial Volume(0.01 cubic inch) [P]_([C]-[J])/[J] Initial Moisture Content(o.1%) 6.7% 6.0% 6.6% [Q]_[C]/[M]*3.81 Initial Wet Density(o.ipcf) 111.6 117.1 110.2 [R]_[Q]/(1+[P]) Initial Dry Density(o.ipcf) 104.6 110.5 103.4 [S]=[P]x[K]x[R]/([K]x62.3)-[R] Initial Saturation(0.m 31.9% 32.9% 30.1% [T]_[R]/[L] Initial Relative Compaction(o.i%) 98.1% 1 103.7% 1 97.0% [U]_[M]X[G] Final Volume(0.01 cubic inch) 4.52 4.57 4.59 [V]_([H]-[J])/[J] Final Moisture Content(0.1%) 14.1% 14.0% 13.0% [w]_[H]/[U]*3.81 Final Wet Density(o.ipcf) 121.6 126.7 117.2 [x]_[w]/(1+[VH Final Dry Density(o.ipcf) 106.6 111.1 103.7 [Y]=[V]x[K]x[X]/([K]x62.3)-[X] Final Saturation(o.1%) 65.8% 73.7% 56.3% [2]_[x]/[L] Final Relative Compaction(o.1%) 100.0% 104.3% 97.3% 4000 a 3500 • Cohesion 160 = 3000 (psf) 0 2500 z 200o Friction Angle 39 0•'' (degrees) cn 1500 a 1000 r ' w N 500 0 0 500 1000 1500 2000 2500 3000 3500 4000 4500 SURCHARGE PRESSURE, psf Remarks: Reviewed by: JD & S Testing Direct Shear Moisture Content & Density Project Name: Hecate Ortega BESS Project Number: 185805133 Sampled By: CLIENT Sample Date: 4/9/2021 Lab#: 134-7 Source/Location: B4@7 Tested By: M.P. Description: ML Test Date: 4/29/2021 Shearing Rate(in./min.) 0.040 Normal Pressure(psf) 1000 2000 4000 [A] Initial Weight of Wet Soil+Ring(o.1g) 194.7 201.8 202.4 [B] Weight of Ring(0.1g) 46.3 45.8 46.4 [C]_[A]-[B] Initial Weight of Wet Soil (o.1g) 148.4 156.0 156.0 [D] Initial Reading 0.0000 0.0000 0.0000 [E] Final Reading 0.0099 0.0135 0.0062 [F]_[E]-[D] Height Change 0.0099 0.0135 0.0062 [G]=1-[F] Final Height 0.9901 0.9865 0.9938 Shear Strength(psf) 756 1740 2844 [H] Final Weight of Wet Soil (0.1g) 153.9 161.6 161.7 [J] Weight of Dry Soil(o.1g) 132.5 140.8 140.7 [K] Specific Gravity [L] Average Maximum Dry Density(o.lpcf) 114.8 [M] Initial Volume(0.01 cubic inch) [P]_([C]-[J])/[J] Initial Moisture Content(o.1%) 12.0% 10.8% 10.9% [Q]_[C]/[M]*3.81 Initial Wet Density(o.ipcf) 122.9 129.2 129.2 [R]_[Q]/(1+[P]) Initial Dry Density(o.ipcf) 109.7 116.6 116.5 [S]=[P]x[K]x[R]/([K]x62.3)-[R] Initial Saturation(0.m 68.1% 73.0% 73.4% [T]_[R]/[L] Initial Relative Compaction(o.i%) 95.6% 1 101.6% 1 101.5% [U]_[M]X[G] Final Volume(0.01 cubic inch) 4.55 4.54 4.57 [V]_([H]-[J])/[J] Final Moisture Content(0.1%) 16.2% 14.8% 14.9% [w]_[H]/[U]*3.81 Final Wet Density(o.ipcf) 128.7 135.7 134.8 [x]_[w]/(1+[VH Final Dry Density(o.ipcf) 110.8 118.2 117.3 [Y]=[V]x[K]x[X]/([K]x62.3)-[X] Final Saturation(o.1%) 84.3% 94.3% 92.8% [z]_[x]/[L] Final Relative Compaction(o.1%) 96.6% 103.0% 102.2% 3500 Q 3000 Cohesion f 2500 210 (psf) z 2000 Friction Angle 34 W v7 1500 (degrees) a 1000 w i = 500 V) 0 0 500 1000 1500 2000 2500 3000 3500 4000 4500 SURCHARGE PRESSURE, psf Remarks: Reviewed by: AP Engineering and Testing, Inc. DBE I MBE ISBE ^- 2607 Pomona Boulevard I Pomona,CA 91768 t.909.869.6316 1 f.909.869.6318 1 www.aplaboratory.com COMPACTION TEST Client: Stantec Consulting, Inc. AP Number: 21-0427 Project Name: Hecate Ortega BESS Tested By: NG Date: 04/20/21 Project No. : 185805133 Calculated By: NR Date: 04/21/21 Boring No.: B2 Checked By: AP Date: 04/21/21 Sample Type: Bulk Sample Date: 04/09/21 Visual Sample Description: Clayey Sand w/gravel Compaction Method X ASTM D1557 ASTM D698 METHOD A Preparation Method Moist MOLD VOLUME (CU.FT) 0.0333 X Dry Wt. Comp. Soil + Mold (gm.) 3901 4029 4033 3969 Wt. of Mold (gm.) 1860 1860 1860 1860 Net Wt. of Soil gm. 20411 21691 21731 2109 Container No. Wt. of Container (gm.) 142.21 149.70 147.95 152.36 Wet Wt. of Soil + Cont. (gm.) 599.55 547.58 595.73 577.13 Dry Wt. of Soil + Cont. (gm.) 575.26 517.051 553.17 529.40 Moisture Content (%) 5.61 8.31 10.50 12.66 Wet Density(pcf) 134.99 143.45 143.72 139.48 Dry Density(pcf) 1 127.82 132.45 130.06 123.81 Maximum Dry Density(pcf) Optimum Moisture Content (%)Maximum Dry Density w/Rock Correction (pcf)I�H Optimum Moisture Content w/Rock Correction (%)1�8 140 . 100%Saturation @ S.G.=2.6 PROCEDURE USED % ----100%Saturation @S.G.=2.7 - X❑ METHOD A:Percent of Oversize: 18.2% 100%Saturation @ S.G.=2.8 Soil Passing No.4(4.75 mm) Sieve Mold: 4 in.(101.6 mm) diameter 130 Layers: 5 (Five) Blows per layer: 25 (twenty-five) ^ U Q '5 METHOD 8:Percent of Oversize: N/A .N 120 c \ Soil Passing 3/8 in. (9.5 mm) Sieve o Mold: 4 in.(101.6 mm) diameter o \ Layers: 5 (Five) Blows per layer: 25 (twenty-five) 110 \ METHOD C:Percent of Oversize: N/A Soil Passing 3/4 in.(19.0 mm) Sieve \ Mold: 6 in.(152.4 mm) diameter \ Layers: 5 (Five) 100 0 10 20 30 40 Blows per layer: 56 (fifty-six) Moisture(%) AP Engineering and Testing, Inc. DBE I MBE I SBE /,— 2607 Pomona Boulevard I Pomona, CA 91768 t.909.869.6316 1 f.909.869.6318 1 www.aplaboratory.com CORROSION TEST RESULTS Client Name: Stantec Consulting, Inc. AP Job No.: 21-0427 Project Name: Hecate Ortega BESS Date: 04/16/21 Project No.: 185805133 Boring Sample Sample Soil Minimum pH Sulfate Content Chloride Content No. Type Date Description Resistivity (ppm) (ppm) ohm-cm B2 Bulk 04/09/21 Clayey Sand 1,378 7.6 345 35 w/ ravel B4 Bulk 04/09/21 Clayey Sand 2,408 7.7 40 23 NOTES: Resistivity Test and pH: California Test Method 643 Sulfate Content California Test Method 417 Chloride Content : California Test Method 422 ND = Not Detectable NA = Not Sufficient Sample NR = Not Requested