GEOTECHNICAL EXPLORATION REPORT ROPOSED COMMERCIAL/RETAIL DEVELOPMENT 7967, & 8015 BEVERLY BOULEVARD

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1 ADDENDUM TO GEOTECHNICAL EXPLORATION REPORT PROPOSED COMMERCIAL/RETAIL DEVELOPMENT 7967, & 8015 BEVERLY BOULEVARD CITY OF LOS ANGELES, CALIFORNIA Prepared for: OPT Beverly, LLC 6400 South Fiddlers Green Circle, #1820 Greenwood Village, Colorado Project No November 22, 2016

2 November 22, 2016 Project No OPT Beverly, LLC 6400 South Fiddlers Green Circle, #1820 Greenwood Village, Colorado Attention: Subject: Reference: Mr. William Rothacker, Jr. Addendum to Geotechnical Exploration Report Proposed Commercial/Retail Development 7967, & 8015 Beverly Boulevard City of Los Angeles, California Leighton Consulting, Inc., 2016, Updated Geotechnical Exploration Report, Proposed Commercial/Retail Development, 7967, & 8015 Beverly Boulevard, City of Los Angeles, California, Project No , dated October 6, INTRODUCTION In accordance with your request and authorization, Leighton Consulting, Inc. (Leighton) is pleased to present this addendum to our referenced Updated Geotechnical Exploration Report for the project (Leighton, 2016) in response to the items included in the City of Los Angeles Geology and Soils Correction Letter dated November 2, It should be noted that it is our understanding that the proposed development of the western parcel ( & 8015 Beverly Boulevard) has been revised to include a total of three levels below grade, extending the bottom of the lowest basement level to approximately 48 feet below the existing ground surface (bgs). The proposed development for the eastern parcel (7967 Beverly Boulevard) remains the same with two levels planned below grade.

3 RESPONSES TO REVIEW COMMENTS A copy of the Geology and Soils Correction Letter prepared by the City of City of Los Angeles and dated November 2, 2016 is included in Appendix A. For convenience, the items included in the correction letter are presented below in italics before Leighton s responses. Comment No. 1 Provide a revised Geologic Map based on a licensed surveyors prepared topographic base map, clearly depicting the proposed project including retaining wall locations and the location of geologic cross sections. Include on the map any lithologic contacts, bedding attitudes, locations of slumps, landslides, or faults relative to the subject site, proposed topographic profiles, and proposed structures and required Code setbacks ( ). Response to Comment No. 1 Figure 1, Geotechnical Map, included with this addendum report depicts the project site boundaries and limits of excavation for subterranean construction on an ALTA/ACSM Land Title Survey base map. In addition, the Geotechnical Map also shows the locations of our subsurface explorations and geotechnical cross sections A-A through C-C (see Figures 2 and 3). It should be noted that we recently drilled and installed two monitoring wells and one pumping well at the project site for subsequent groundwater sampling for groundwater characterization and design of permanent dewatering system. Attached is the boring log for PW-1 drilled at the western parcel. Due to the proximity of the wells to previous borings, sampling was focused on depths previously unsampled, primarily deeper than 50 feet bgs in boring PW-1. Attached is the boring log for PW-1 drilled at the western parcel. Comment No. 2 Provide geological cross sections illustrating existing and proposed grades and structures. Clearly depict any surcharging buildings on the cross section(s). Response to Comment No. 2 Please see Figures 2 and 3, Geotechnical Cross Sections A-A through C-C, included with this report. 2

4 Comment No. 3 The Department does not accept liquefaction analysis solely based on CPT sounding data. Analysis must be based on SPT data. CPT sounding data may be utilized to more precisely establish boundaries between layers. Provide analysis based on SPT data. Response to Comment No. 3 To specifically enable CPT/SPT correlation, the boring PW-1 was performed immediately adjacent to CPT-1. However, because sampling was not performed in PW- 1 for depths shallower than 30 feet, the SPT and Modified California sampler data from the adjacent boring LB-1 was used for depths shallower than 30 feet. Fines content was estimated for each layer based on boring logs and CPT correlations. As shown in Appendix C, Liquefaction Analysis, there is good correlation between the CPT- and SPT-based cyclic resistance ratios (CRRs). However, more liquefiable layers are identified in the CPT analysis. This is as expected because thin, discrete sandy layers cannot be identified by SPTs performed at 5-foot intervals. Based on the above discussion, liquefaction susceptibility and seismic settlement was evaluated using CPT data. All layers were included in the seismic settlement calculation. No layers were omitted based on factor of safety. Results of our analysis indicate the potential for liquefaction at the site is low. The results of the liquefaction analysis are provided in Appendix C. Comment No. 4 Provide design calculations to substantiate the recommendations for temporary excavations and permanent walls for a minimum factor of safety of 1.25 and 1.5, respectively. Response to Comment No. 4 The requested slope stability analysis results are presented in Appendix D. We used peak shear strengths to evaluate temporary conditions and ultimate shear strengths to evaluate permanent conditions. Results indicate that 23 pounds per cubic foot (pcf) of equivalent fluid pressure is sufficient to obtain a factor of safety of We recommended 35 pcf for cantilevered shoring. 3

11143.002 The recommended uniform rectangular earth pressure of 25H (where H is the height of the shored wall) for braced excavation results in a factor of safety of 1.66.

If you have any questions or if we can be of further service, please contact us at (866) LEIGHTON; specifically at the phone extensions or e-mail as listed below.

5 The recommended uniform rectangular earth pressure of 25H (where H is the height of the shored wall) for braced excavation results in a factor of safety of The recommended permanent basement at-rest wall pressure of 55 pcf results in a factor of safety of CLOSING We appreciate the opportunity to be of continued service on this project. If you have any questions or if we can be of further service, please contact us at (866) LEIGHTON; specifically at the phone extensions or as listed below. Respectfully submitted, LEIGHTON CONSULTING, INC. Jeffrey M. Pflueger, PG, CEG 2499 Associate Geologist Extension 4257, jpflueger@leightongroup.com JMP/CCK/lr Carl C. Kim, PE, GE 2620 Senior Principal Engineer Extension: 4262, ckim@leightongroup.com Attachments: Figure 1 Geotechnical Map Figure 2 Geotechnical Cross Section A-A Figure 3 Geotechnical Cross Section B-B and C-C Distribution: (1) Addressee Appendix A City of Los Angeles Geology and Soils Report Correction Letter dated November 2, 2016 Appendix B Geotechnical Boring and Pumping Well Log PW-1 Appendix C Liquefaction Analysis Appendix D Slope Stability Analysis 4

6 Approximate Location of Hollow Stem Auger Boring Converted to Pumping Well & > Approximate Location of Hollow Stem Auger Boring Converted to Monitoring Well!, Approximate Location of Cone Penetration Test (CPT) & Approximate Location of Hollow Stem Auger Boring ( & % Geotechnical Cross Section Limits of Excavation Edinburrgh Avenue Legend % Approximate Site Boundary 0 ³ Beverly Boulevard Beverly Boulevard Feet Project: Eng/Geol: CCK/JMP Scale: 1 " = 30 ' Date: November 2016 Base Map: ESRI ArcGIS Online 2016 Travis Edwards.JRN Civil Engineers, Thematic Information: Leighton Author: Leighton Geomatics (btran) Map Saved as V:\Drafting\11143\002\Maps\11143_002_F01_GM_ mxd on 11/11/2016 9:10:39 AM GEOTECHNICAL MAP Figure , , & 8015 Beverly Boulevard Los Angeles, California Leighton

7 Western Parcel ( & 8015 Beverly Boulevard) Eastern Parcel (7967 Beverly Boulevard) A Existing Building Proposed Building Existing Building Qa LB-3 (Proj. I 15') CPT-2 (Proj. I 20') T.D.11.5' LB-2 (Proj. I 24') T.D.21.5' G.W.@11.9' CPT-1 (Proj. I 22')/ Afu PW-1 (Proj. I 22') MW-1 (Proj. I 5') LB-1 (Proj. I 15') Qa Existing Building N. Edinburgh Avenue Existing Building Proposed Building Afu Qa LB-4 (Proj. I 27') LB-5 (Proj. I 17')/ LB-6 (Proj. I 13') T.D.11.5' Existing Parking Lot A' ELEVATION (FEET) Proposed Subterranean Structure T.D.54.3' T.D.75.6' T.D.51.5' G.W.@13.9' T.D.71.5' G.W.12'/14' Proposed Subterranean Structure T.D.76.5' G.W.@13.9' ELEVATION (FEET) W-E Proj: Eng/Geol: CCK/JMP Scale: 1"=30' Date: November 2016 Reference: CROSS SECTION A-A' 7969, , & 8015 Beverly Boulevard Los Angeles, California Figure 2 Leighton V:\DRAFTING\11143\002\CAD\ \ _F02-03_CS_ DWG ( :58:28PM) Plotted by: btran

8 Existing Alley PW-1 (Proj. I 12') CPT-1 (Proj. I 10') LB-3 (Proj. I 34') LB-1 (Proj. I 13') T.D.11.5' MW-1 (Proj. I 12') Western Parcel ( & 8015 Beverly Boulevard) CPT-2 (Proj. I 27') LB-2 (Proj. I 12') Afu T.D.21.5' G.W.@11.9' Existing Building Qa Proposed Building Beverly Boulevard T.D.11.5' Afu Eastern Parcel (7967 Beverly Boulevard) B B' C C' Existing Alley LB-6 (Proj. I 13') LB-5 (Proj. I 11') T.D.11.5' LB-4 (Proj. I 7') Existing Building Qa Proposed Building Beverly Boulevard ELEVATION (FEET) T.D.71.5' G.W.@12' T.D.51.5' G.W.@13.9' T.D.75.6' T.D.71.5' G.W.@14' T.D.54.3' Proposed Subterranean Structure ELEVATION (FEET) ELEVATION (FEET) Proposed Subterranean Structure T.D.76.5' G.W.@13.9' ELEVATION (FEET) N-S N-S Proj: Eng/Geol: CCK/JMP Scale: 1"=30' Date: November 2016 Reference: CROSS SECTION B-B' AND C-C' 7969, , & 8015 Beverly Boulevard Los Angeles, California Figure 3 Leighton V:\DRAFTING\11143\002\CAD\ \ _F02-03_CS_ DWG ( :58:50PM) Plotted by: btran

9 APPENDIX A City of Los Angeles Geology and Soils Report Correction Letter dated November 2, 2016

12 APPENDIX B Geotechnical Boring and Pumping Well Log PW-1

13 GEOTECHNICAL BORING AND MONITORING WELL LOG PW-1 Project No. Project Drilling Co. Drilling Method Location OPT Beverly J & H Drilling Co. Hollow Stem Auger - 140lb - Autohammer - 30" Drop 8001 Beverly Blvd., Los Angeles, CA Starting Drill Date Ending Drill Date Hole Diameter Ground Elevation Logged / Inspected By " 188' BM / SAM Elevation Feet 0Depth Feet N Graphic Log S Sample No. Blows Per 6 Inches Dry Density pcf Moisture Content, % Soil Class. (U.S.C.S.) SOIL DESCRIPTION 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 3.5-inches asphalt concrete (AC) over 5-inches aggregate base (AB) Artificial fill, uncertified (Afu) WELL DIAGRAM Cement Seal at 0-2' and Traffic Rated Well Box at Surface Type of Tests Quaternary Alluvium (Qal) 4" Solid PVC Casing at 0'-20' Cement/Bentonite Grout Backfill at 2'-10' Bentonite Seal at 10'-12' #2/12 Sand Filter Pack at 12'-71.5' " Slotted (0.020) PVC Casing at 20'-70' SAMPLE TYPES: B BULK SAMPLE C CORE SAMPLE G GRAB SAMPLE R RING SAMPLE S SPLIT SPOON SAMPLE T TUBE SAMPLE TYPE OF TESTS: -200 % FINES PASSING AL ATTERBERG LIMITS CN CONSOLIDATION CO COLLAPSE CR CORROSION CU 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 * * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 1 of 3

14 GEOTECHNICAL BORING AND MONITORING WELL LOG PW-1 Project No. Project Drilling Co. Drilling Method Location OPT Beverly J & H Drilling Co. Hollow Stem Auger - 140lb - Autohammer - 30" Drop 8001 Beverly Blvd., Los Angeles, CA Starting Drill Date Ending Drill Date Hole Diameter Ground Elevation Logged / Inspected By " 188' BM / SAM Elevation Feet Depth Feet 30 N Graphic Log S Sample No. Blows Per 6 Inches Dry Density pcf Moisture Content, % Soil Class. (U.S.C.S.) SOIL DESCRIPTION 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. WELL DIAGRAM Type of Tests 155 S Sandy CLAY, bluish gray, moist, very stiff, non-plastic to low plasticity, fine to medium sand S2 8 6 Sandy CLAY, bluish gray, very moist to wet, stiff, non-plastic, fine to coarse sand with a few Poorly graded sand layer #2/12 Sand Filter Pack at 15'-71.5' 145 S Sandy CLAY, bluish gray, wet, medium dense/very stiff, low plasticity, fine to medium sand, few gravels 45 4" Slotted (0.020) PVC Casing at 20'-70' 140 S Gravelly SAND, bluish gray, wet, dense, medium to coarse sand, few 1-2" gravels 50 S SAND, bluish green to white, wet, dense, fine to medium sand 135 S Clayey SAND, bluish gray to gray, very moist, medium dense, medium to coarse sand, grades into clay 55 S Silty SAND, bluish gray, moist to very moist, dense, fine to medium sand, some clay 130 S Clayey SAND, bluish gray, moist, dense, fine to medium sand 60 SAMPLE TYPES: B BULK SAMPLE C CORE SAMPLE G GRAB SAMPLE R RING SAMPLE S SPLIT SPOON SAMPLE T TUBE SAMPLE TYPE OF TESTS: -200 % FINES PASSING AL ATTERBERG LIMITS CN CONSOLIDATION CO COLLAPSE CR CORROSION CU 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 * * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 2 of 3

GEOTECHNICAL BORING AND MONITORING WELL LOG PW-1 Project No. Project Drilling Co. Drilling Method Location 11143.005 OPT Beverly J & H Drilling Co.

15 GEOTECHNICAL BORING AND MONITORING WELL LOG PW-1 Project No. Project Drilling Co. Drilling Method Location OPT Beverly J & H Drilling Co. Hollow Stem Auger - 140lb - Autohammer - 30" Drop 8001 Beverly Blvd., Los Angeles, CA Starting Drill Date Ending Drill Date Hole Diameter Ground Elevation Logged / Inspected By " 188' BM / SAM Elevation Feet Depth Feet 60 N Graphic Log S Sample No. S9 Blows Per 6 Inches Dry Density pcf Moisture Content, % Soil Class. (U.S.C.S.) SC SOIL DESCRIPTION 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 Clayey SAND, bluish gray, moist to very moist, medium dense, fine to medium sand WELL DIAGRAM Type of Tests 125 S Clayey SAND, bluish gray, very moist, medium dense, fine to medium sand #2/12 Sand Filter Pack at 15'-71.5' 65 S Clayey SAND, bluish gray, very moist, medium dense, fine to medium sand, shell fragments present 4" Slotted (0.020) PVC Casing at 20'-70' 120 S Same as above S Clayey SAND, bluish gray, moist, medium dense, fine to coarse sand, some shell fragments Total Depth of Boring: 71.5 feet Groundwater encountered at 12 feet Pumping well installed per Well Diagram on 11/2/ SAMPLE TYPES: B BULK SAMPLE C CORE SAMPLE G GRAB SAMPLE R RING SAMPLE S SPLIT SPOON SAMPLE T TUBE SAMPLE TYPE OF TESTS: -200 % FINES PASSING AL ATTERBERG LIMITS CN CONSOLIDATION CO COLLAPSE CR CORROSION CU 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 * * * This log is a part of a report by Leighton and should not be used as a stand-alone document. * * * Page 3 of 3

16 APPENDIX C Liquefaction Analysis

17 Leighton Consulting, Inc. Geotechnical Engineers Cowan Irvine, CA SPT BASED LIQ UEFACTION ANALYSIS REPORT Project title : OPT Beverly CPT file : CPT-01 :: Input parameters and analysis properties :: Analysis method: Fines correction method: Sampling method: Borehole diameter: Rod length: Hammer energy ratio: NCEER 1998 Idriss & Seed Sampler wo liners 65 mm to 11 5mm G.W.T. (in-situ): G.W.T. (earthq.): Earthquake magnitude M w : Peak ground acceleration: SPT results rounding mode: Location : 7967, , & 8015 Beverly Blvd. Los Angeles Nearest N SPT N SPT plot plot 5.00 N(SPT) N1(60) N1(60)cs CSR CSR vs CRR vs CRR plot plot CRR CPT CSR CRR Depth (ft) Depth (ft) SPT Blow Count CSR & CRR Liquefaction CRR CRR clean clean sand sand curve curve 0.50 Cyclic Stress Ratio No Liquefaction Corrected Blow Count N1(60),cs CLiq v CPT Liquefaction Assessment Software - Report created on: 11/22/2016, 1:38:27 PM Project file: C:\Users\carl\OneDrive\Documents\2015 projects\11143 OPT Beverly\Analyses\Cliq\11143 Liquefaction2.clq 1

18 This software is licensed to: Carl Kim CPT name: CPT-01 :: Cyclic Stress Ratio fully adjusted (CSR*) numeric results :: No Depth (ft) Weight (pcf) u o (tsf) σ v (tsf) σ' v (tsf) r d CSR K σ MSF CSR * Abbreviations Depth: u 0: σ v: σ v': r d: CSR: MSF: K σ: CSR * : Depth from free surface where SPT was performed (ft) Water pressure at test point (tsf) Total overburden pressure at test point (tsf) Effective overburden pressure based on GWT during earthquake (tsf) Nonlinear shear mass factor Cyclic Stress Ratio () Effective overburden stress factor Magnitude Scaling Factor CSR fully adjusted :: Cyclic Resistance Ratio (CRR) numeric results :: No Depth (ft) Fines % u o (tsf) σ v (tsf) σ' v (tsf) N SPT C N C R C B C S C E N 1(60) α β N 1(60),cs CRR 7.5 F.S CLiq v CPT Liquefaction Assessment Software - Report created on: 11/22/2016, 1:38:27 PM Project file: C:\Users\carl\OneDrive\Documents\2015 projects\11143 OPT Beverly\Analyses\Cliq\11143 Liquefaction2.clq 2

19 This software is licensed to: Carl Kim CPT name: CPT-01 :: Cyclic Resistance Ratio (CRR) numeric results :: No Depth (ft) Fines % u o (tsf) σ v (tsf) σ' v (tsf) N SPT C N C R C B C S C E N 1(60) α β N 1(60),cs CRR 7.5 F.S Abbreviations Depth: Weight: u 0: σ v: σ v': N SPT: C N: C E: Depth from free surface where SPT was performed (ft) Soil unit weight from previous test point to current (pcf) Water pressure at test point (tsf) Total overburden pressure at test point (tsf) Effective overburden pressure based on in situ GWT (tsf) Number of blows count in the field (blows/feet) Overburden pressure factor Energy ratio factor C B: C R: C S: N 1(60): α: β: N 1(60),cs: CRR 7.5: F.S.: Borehole diameter factor Rod length factor Sampling method factor Number of blows corrected for 60% energy Fines correction coefficient Fines correction coefficient Number of blows corrected for 60% energy and fines Cyclic Resistance Ratio for M<sub>w</sub> 7.50 Factor of safety against liquefaction CLiq v CPT Liquefaction Assessment Software - Report created on: 11/22/2016, 1:38:27 PM Project file: C:\Users\carl\OneDrive\Documents\2015 projects\11143 OPT Beverly\Analyses\Cliq\11143 Liquefaction2.clq 3

20 APPENDIX D Slope Stability Analysis

21 Cross Section A-A': Slope Stability - Temporary P:\INFOCUS PROJECTS\ \11143 OPT Beverly\002 Design Geo Exploration and Soil Gas Survey\Analyses\CS A-A' Slope Stability Static At rest.slim Method: bishop simplified Factor of Safety: 1.25 Center: , Radius: Left Slip Surface Endpoint: , Right Slip Surface Endpoint: , Left Slope Intercept: Right Slope Intercept: lbs/ft2 250 W CLAY lbs/ft2 Material Name Color Unit Weight (lbs/ 3) Sat. Unit Weight (lbs/ 3) Strength Type Cohesion (psf) Phi (deg) Water Surface 100 CLAY Mohr Coulomb Water Surface SLIDEINTERPRET Project PROPOSED COMMERCIAL/RETAIL DEVELOPMENT Analyzed By Date SP Units November 2016 feet Condition Scale Static 1:360 Project No.:

22 Cross Section A-A': Slope Stability - Temporary P:\INFOCUS PROJECTS\ \11143 OPT Beverly\002 Design Geo Exploration and Soil Gas Survey\Analyses\CS A-A' Slope Stability Static At rest_rectangular.slim Method: bishop simplified Factor of Safety: 1.66 Center: , Radius: Left Slip Surface Endpoint: , Right Slip Surface Endpoint: , Left Slope Intercept: Right Slope Intercept: W lbs/ft2 CLAY Material Name Color Unit Weight (lbs/ 3) Sat. Unit Weight (lbs/ 3) Strength Type Cohesion (psf) Phi (deg) Water Surface 100 CLAY Mohr Coulomb Water Surface Project SLIDEINTERPRET PROPOSED COMMERCIAL/RETAIL DEVELOPMENT Analyzed By Date SP Units November 2016 feet Condition Scale Static 1:360 Project No.:

23 Cross Section A-A': Slope Stability - Permanent P:\INFOCUS PROJECTS\ \11143 OPT Beverly\002 Design Geo Exploration and Soil Gas Survey\Analyses\CS A-A' Slope Stability Static At rest_permanent.slim Method: bishop simplified Factor of Safety: 1.54 Center: , Radius: Left Slip Surface Endpoint: , Right Slip Surface Endpoint: , Left Slope Intercept: Right Slope Intercept: lbs/ft2 250 W CLAY lbs/ft2 Material Name Color Unit Weight (lbs/ 3) Sat. Unit Weight (lbs/ 3) Strength Type Cohesion (psf) Phi (deg) Water Surface 100 CLAY Mohr Coulomb Water Surface SLIDEINTERPRET Project PROPOSED COMMERCIAL/RETAIL DEVELOPMENT Analyzed By Date SP Units November 2016 feet Condition Scale Static 1:360 Project No.:

September 7, 2017 (Revised November 1, 2017)

September 7, 2017 (Revised November 1, 2017) Project No. 10113.002 Environmental Advisors 2400 East Katella Avenue, Suite 800 Anaheim, California 92806 Attention: Subject: Mr. Greg McCafferty Response