City Market Los Angeles Technical Appendices to the Draft EIR

Transcription

1 City Market Los Angeles Technical Appendices to the Draft EIR Appendix F Preliminary Geotechnical Engineering Investigation SASSAN Geosciences, Inc., December 2012

2 MR. PETER M. FLEMING THE CITY MARKET OF LOS ANGELES 1057 SAN PEDRO STREET LOS ANGELES, CALIFORNIA PRELIMINARY GEOTECHNICAL ENGINEERING INVESTIGATION FOR THE CITY MARKET OF LOS ANGELES Prepared By SASSAN Geosciences, Inc North Lake Avenue, Suite 204 Pasadena, California December 27, 2012

3 SAS SASSAN Geosciences, Inc. December 27, 2012 Mr. Peter M. Fleming THE CITY MARKET OF LOS ANGELES 1057 San Pedro Street Los Angeles, CA Subject: Preliminary Geotechnical Engineering Investigation Project Address: THE CITY MARKET OF LOS ANGELES SAS File Number: 2FLE045 Dear Mr. Fleming: SASSAN Geosciences, Inc. (SAS) has completed the preliminary geotechnical engineering investigation for the subject property. Our investigation was performed to determine the nature of surface and subsurface soils and to evaluate their physical and engineering properties. The results were then analyzed, and recommendations for foundation design and related parameters were prepared. This report presents our findings and recommendations North Lake Avenue. Suite 204. Pasadena. California (626) Fax (626)

4 LOCATION AND SITE DESCRIPTION The subject property is located in Downtown section of the City of Los Angeles, California. The subject project includes all properties bounded by 9 th Street on the north, by 12 th Street on the south, by San Pedro Street on the east and by San Julian Street on the west, as well as two properties to the west of San Julian Street. A vicinity map is presented on Figure A-1 in Appendix A. This project site is located in a relatively level, commercial area, and is comprised of various one-story and two-story commercial and office buildings with associated parking lots. Most of the structures located between 9 th Street and 12 th Street are already demolished or are currently under demolition. A plot plan indicating the boundaries of the subject project and the locations of the existing improvements is presented on Figure A-2 in Appendix A. OBJECTIVE The owners wish to assess the geotechnical characteristics of the underlying ground in order to demolish the existing structures and construct a commercial and residential building complex. The complex will consist of various multi-story buildings with full subterranean parking structures. The review of the current architectural plans indicates that the proposed buildings are anticipated to be two (2) to eight (8) stories high with two residential towers up to twenty-eight (28) stories high. The proposed subterranean parking structures are anticipated to be up to three (3) levels below ground. A plot plan indicating the locations of the existing and proposed improvements is presented on Figure A-2 in Appendix A. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 2 of 24

5 FIELD INVESTIGATION Subsurface exploration was performed on August 18 through September 26, 2012 and involved drilling nine (9) boreholes (Boreholes B-1 through B-9) to a maximum depth of approximately seventy (70) feet. Additional exploration was performed on October 16 through 26, 2012 and involved drilling nine (9) boreholes (Test Holes TH-1 through TH- 9) to a maximum depth of approximately forty (40) feet. The drilling operation was performed utilizing a twenty-four (24)-inch diameter flight auger mounted on a drilling rig. Two and one-half-inch (2.5) diameter split spoon ring samples and standard penetration test (T) samples were obtained from the boreholes with a thirty (30) inch drop of a one-hundred-forty (140) pound hammer. Earth materials encountered were classified in accordance with the visual-manual procedures of the Unified Soil Classification System. A plot plan indicating the approximate borehole locations is presented on Figure A-2 in Appendix A. EARTH MATERIALS The earth materials encountered in the boreholes consist of up to approximately five (5) feet of fill underlain by alluvium, which extends to the depths explored. Detailed logs of the boreholes are presented on Figures B-1 through B-18 in Appendix B. A copy of a regional geologic map (Dibblee) is presented on Figure D-1 in Appendix D. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 3 of 24

6 The density of alluvium increases by depth, however, the conventional earth moving machinery should be able to handle the grading operation. We do not anticipate that ripability becomes an issue during the grading at the subject site. In addition, relatively clean sands will be encountered during the drilling of the friction piles. This may result in caving. As such, the contractor is advised to have steel casing ready to use when and if caving occurs. GROUNDWATER Groundwater seepage was not encountered in the boreholes to the depths explored, and is not anticipated to impact the proposed construction. In addition, Seismic Hazard Evaluation for the Hollywood Quadrangle by the State of California indicates that the highest historic water level in this area was recorded at approximately one-hundred (100) feet below ground surface. A copy of Highest Ground Water Levels map is presented on Figure C-2 in Appendix C. LABORATORY TESTING Moisture content (ASTM D 2216) and shear strength (ASTM D 3080) tests were performed for selected samples of soil considered to be representative of those encountered. The results of direct shear tests are presented on Figures B-19 through B-21 in Appendix B. Evaluation of the test data is reflected throughout this report. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 4 of 24

7 LIQUEFACTION The subject property is shown on the State of California Seismic Hazard Zones map presented on Figure C-1 in Appendix C. The site is located outside of the seismically induced liquefaction hazard zone. CONCLUSIONS AND RECOMMENDATIONS Discussion Architectural plans and/or construction concept plans are not completed at this time. The recommendations provided in this report are based on the current conceptual architectural plans. The shoring and foundation design recommendations, provided in this report, may change if significant changes are made to the size and locations of the proposed structures. General The referenced property is considered to be suitable for the proposed construction from a geotechnical engineering standpoint, provided that our recommendations are incorporated into the approved construction plans. The conclusions and recommendations presented here are based on our observations at the site during our investigation, engineering judgment, and analysis of the soil samples obtained from the boreholes. Minor variations of subsurface conditions are common, and major variations are possible. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 5 of 24

8 General Grading Grading areas must be stripped of all vegetation, debris and other deleterious material. All loose soil disturbed by the removal of structures must be removed and recompacted. The existing fill is up to approximately vive (5) feet thick and is not suitable for foundation support. At locations where new fill is proposed, the existing fill must be entirely removed and replaced with a certified engineered fill. The proposed new fill must be placed in horizontal layers, and must be benched into the competent alluvium. Temporary Excavations Architectural plans and/or construction concept plans are not completed at this time. However, the review of available architectural concept plans indicates that temporary excavations up to approximately thirty (30) feet in depth will be required during construction of the proposed subterranean parking structures. The temporary excavations along the streets will be surcharged by the street traffic. At other locations, the temporary excavations will be surcharged by the neighboring one-story and two-story structures located adjacent to the property lines. Shoring must be designed for the surcharged temporary excavations. The recommendations and necessary strength parameters needed in the design of temporary shoring elements are provided in the following sections of this report. Based on the integrity of the site earth materials, it is our opinion that unsurcharged temporary excavations may be performed continuously in accordance with the following table: SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 6 of 24

9 Maximum Maximum Depth of Cut Slope Ratio (ft) (H:V) 0-5 Vertical >5 1:1 The contractor must perform the temporary excavations over five (5) feet in depth and installation of the shoring under continuous monitoring of a Registered Grading Deputy Inspector who would ensure the quality of grading and presence of competent earth materials. The excavations may be left open for a temporary period of four (4) weeks. A grading inspector must be present when laborers are working within five (5) feet of the temporary cut area. Temporary Shoring Installation Based on current conceptual architectural plans, temporary excavations up to approximately thirty (30) feet in height will be required during the construction of the subterranean garage. The temporary shoring may consist of wide flange I-beams imbedded in concrete soldier piles and wooden lagging that spans between the I-beams. For shallow excavations, the shoring may be design with cantilevered soldier piles. For deeper excavations, where possible, the soldier piles may be secured with tie-backs (with or without post-grouting). Where using the tie-backs is not feasible, the soldier piles may be supported by rakers and a concrete deadman. The temporary excavations may commence only after installation of the soldier piles of the temporary shoring system. The final design of the shoring must be performed by the consulting civil engineer in SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 7 of 24

10 conjunction with this office. The recommendations for design of the soldier piles, tiebacks and deadman are provided in Shoring Design Recommendations section of this report. The installation of the temporary shoring must be performed in the following order: 1. The soldier piles must be drilled from the existing surface down to the required depth (to be determined by the consulting civil engineer). 2. Steel I-beams for temporary shoring must be installed. 3. The soldier piles must be filled with concrete up to six (6) inches below the bottom of the proposed footings. 4. The rest of the soldier pile must be filled with one-sack-slurry up to the existing surface. 5. The excavation may be performed up to five (5) feet below the existing grade. Due to granular nature of the underlying earth materials, this number may be reduced by the consulting soils engineer during the excavation process. 6. The wooden lagging must be installed between the I-beams up to the bottom of the excavation. 7. The lagging must be backfilled with incompressible material such as compacted construction sand or a half-sack-slurry. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 8 of 24

11 8. The excavation may be performed up to the design depth (bottom of the proposed footings or grade beams) in five-foot vertical intervals (or as instructed by the consulting soils engineer) repeating steps five through seven. 9. The wooden lagging may be installed up to the level of the top of the proposed footings or grade beams. 10. Where possible, tie-backs may be drilled and installed at the levels specified on the approved shoring plans. The tie-backs may be post-grouted. 11. The tie-backs must be tested per specifications provided on the approved shoring plans. 12. Where using the tie-backs is not feasible, the soldier piles of the temporary shoring system may be supported by rakers and a concrete deadman. The soldier piles must be supported by a temporary soil embankment, which may be removed only after the installation of the proposed rakers and concrete deadman per specifications provided on the approved shoring plans. 13. A Registered Grading Deputy Inspector approved by and responsible to this office will be required to provide continuous inspection during the drilling of the proposed soldier piles and installation of temporary shoring. Temporary Shoring Design Recommendations The temporary shoring may consist of wide flange I-beams imbedded in concrete soldier piles and wooden lagging that spans between the I-beams. The pressure distribution SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 9 of 24

12 diagrams for the design of the soldier piles of the temporary shoring is presented in Appendix E. The final design of the shoring must be performed by the consulting shoring engineer. The following minimums apply to the design of the shoring elements: 1. Soldier piles of the temporary shoring system must be founded at a minimum depth of eight (8) feet into undisturbed alluvium. The actual depth of soldier piles, however, must be determined by the consulting civil engineer in conjunction with this office. 2. Soldier piles must have a minimum diameter of twenty-four (24) inches. 3. The pile excavations must be covered if left overnight. 4. Soldier piles must be assumed fixed at two (2) feet into alluvium. 5. Active earth pressure increasing at minimum rate of 45 psf per foot of depth must be used in the design of shoring elements. The results of the active earth pressure analyses are presented in Appendix E. 6. Passive earth pressure increasing at a minimum rate of 300 psf per foot of depth, to a maximum of 3,000 psf, must be applied to portions of the soldier piles that are embedded a minimum two (2) feet into alluvium. 7. The suggested passive pressure may be doubled for an isolated pile condition (d>2.5d). 8. A side friction value of 500 psf in compression and 250 psf in tension may be utilized for the portion of the soldier piles that are penetrated into alluvium. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 10 of 24

13 9. The drilled tie-backs must have a minimum diameter of six (6) inches. 10. The tie-backs must have a minimum bonding length of twenty (20) feet beyond the active wedge. 11. The inclination of the failure plane of the active wedge may be assumed to be at 35 degrees, measured from the vertical. 12. A skin friction value of 1,440 psf (10 psi) with post-grouting and value of 600 psf (4 psi) without post-grouting may be utilized for the portions of the tie-backs within the bonding length. 13. The shoring elements must be designed such that only one-quarter (¼) of the total lateral load from the earth pressure is carried by the tie-backs, and three-quarters (¾) of the total lateral load is carried by the shoring columns. 14. An allowable bearing capacity of 2,000 psf must be used for a deadman twenty-four (24) inches wide and founded twenty-four (24) inches into undisturbed alluvium. The allowable bearing capacity may be increased by twenty (20) percent for every additional foot of width or depth to a maximum value of 4,000 psf. 15. Passive earth pressure increasing at the rate of 300 psf per foot of depth, to a maximum of 3,000 psf, must be used in the design of the deadman. 16. A coefficient of friction of 0.35 must be utilized for resisting lateral loads at the contact surface of the concrete deadman and foundation soils. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 11 of 24

14 17. The maximum allowable lateral deflection of 0.5 inch must be considered for the design of the shoring elements. Shoring Monitoring Program After completion of the installation, the shoring must be periodically monitored by a licensed surveyor for a lateral deflection of the vertical elements. The monitoring of the shoring must be performed not less than once every week. The first reading must be taken immediately after the completion of installation of the shoring, and consecutive readings must be taken on a weekly basis. The maximum lateral deflection of the shoring system must be limited to one half (½) of an inch. In the event that lateral movements of the shoring in excess of one half (½) of an inch are encountered, the consulting geotechnicalengineer-of-record and structural -engineer-of-record must be notified immediately. Foundations The review of the current architectural plans indicates that the proposed buildings are anticipated to be two (2) to eight (8) stories high with two residential towers up to twentyeight (28) stories high. The proposed subterranean parking structures are anticipated to be up to three (3) levels below the ground. The proposed structures up to ten-stories high may be supported by continuous footings, spread footings, or a combination of both. The proposed structures over ten-stories high must be supported on a grade beam/friction pile combination footing. Following are the recommendations for both: conventional footings and deep foundations. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 12 of 24

15 Due to the fact that all surcharged temporary excavations will be supported by soldier piles, the consulting structural engineer may elect to support all proposed structures on grade beam/friction pile combination footing. In this case, all shoring soldier piles must be designed per recommendations provided later in this section for deep foundations. Conventional Footings - The proposed structures up to ten-stories high may be supported by continuous footings, spread footings, or a combination of both. Footings must be founded into undisturbed alluvium. In addition, the bottoms of proposed footings must be below a plane with a slope of one horizontal to one vertical (1:1) projected upward from the bottom edge of adjacent existing footings. A bearing capacity of up to the maximum value of 2,000 psf may be used for footings twenty-four (24) inches wide and founded twenty-four (24) inches into undisturbed alluvium. The allowable bearing capacity may be increased by twenty (20) percent for every additional foot of width or depth to a maximum value of 4,000 psf. The allowable bearing value is for dead-plus-live loads and may be increased by thirty (30) percent for momentary wind and seismic loads. The following minimums apply to all footings: 1. Footings must be founded at a minimum depth of twenty-four (24) inches into undisturbed alluvium. 2. Footings must be reinforced with a minimum of four (4) #4 bars - two at the top and two at the bottom. The final design of the footings must be provided by a structural engineer in conjunction with this office. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 13 of 24

16 3. A coefficient of friction of 0.35 must be utilized for resisting lateral loads at the contact surface of concrete and foundation soils. 4. Active earth pressure increasing at minimum rate of 54 psf per foot of depth must be used in the design of cantilevered retaining walls. The results of the active earth pressure analyses are presented in Appendix F. Additional earth pressure increasing at a minimum rate of 10 psf per foot of depth due to seismic forces must be applied to cantilevered retaining walls that are equal or higher than twelve (12) feet in a form of an inverted triangle, and the resultant force due to seismic pressure must be applied at an elevation equal to 60 per cent of the retained height. The results of the seismic earth pressure analyses are presented in Appendix G. 5. At-rest earth pressure increasing at the rate of 80 psf per foot of depth must be used in the design of the retaining walls that are braced at the top and the bottom. The results of the at-rest earth pressure analyses are presented in Appendix F. 6. Passive earth pressure increasing at a maximum rate of 300 psf per foot of depth, to a maximum of 3,000 psf, may be used in calculations. Deep Foundations - The proposed structures over ten-stories high must be supported on a grade beam/friction pile combination footing. The following recommendations should be implemented. A side friction value of 500 psf in compression and 250 psf in tension must be utilized for the portion of the friction piles that are penetrated into undisturbed alluvium. The allowable side friction values may be increased by thirty (30) percent for momentary wind and seismic loads. The following minimums apply to the friction piles: SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 14 of 24

17 1. Friction piles must be founded at a minimum depth of eight (8) feet into undisturbed alluvium. The actual depth of friction piles, however, must be determined by the structural engineer in conjunction with this office. 2. Friction piles must have a minimum diameter of twenty-four (24) inches. 3. The pile excavations must be covered if left overnight. 4. A Registered Grading Deputy Inspector approved by and responsible to this office will be required to provide continuous inspection for the proposed friction pile drilling and installation. 5. Active earth pressure increasing at minimum rate of 54 psf per foot of depth must be used in the design of cantilevered retaining walls. The results of the active earth pressure analyses are presented in Appendix F. Additional earth pressure increasing at a minimum rate of 10 psf per foot of depth due to seismic forces must be applied to cantilevered retaining walls that are equal or higher than twelve (12) feet in a form of an inverted triangle, and the resultant force due to seismic pressure must be applied at an elevation equal to 60 per cent of the retained height. The results of the seismic earth pressure analyses are presented in Appendix G. 6. At-rest earth pressure increasing at the rate of 80 psf per foot of depth must be used in the design of the retaining walls that are braced at the top and the bottom. The results of the at-rest earth pressure analyses are presented in Appendix F. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 15 of 24

18 7. Passive earth pressure increasing at a maximum rate of 300 psf per foot of depth, to a maximum of 3,000 psf, must be applied to portions of the friction piles that are embedded a minimum two (2) feet into undisturbed alluvium. 8. The suggested passive pressure may be doubled for an isolated pile condition (d>2.5d). 9. Due to granular nature of underlying earth materials, caving may be encountered during the drilling of the friction piles. As such, the contractor is advised to have steel casing ready to use when and if caving occurs. In addition, if water is present in the drilled shafts, a tremie pipe must be used by the contractor to pump the concrete into the drilled shafts from the bottom under the standing water. Subdrain System The retaining walls must be provided with weep holes or perforated pipe and gravel subdrain to prevent entrapment of water in the backfill. The perforated pipe must consist of four-inch (4 ) minimum diameter PVC Schedule 40, or ABS SDR-35, with a minimum of sixteen (16) perforations per foot on the bottom one-third of the pipe. Every foot of the pipe should be embedded in three (3) cubic feet of three-quarter-inch (3/4 ) gravel wrapped in filter fabric (Mirafi 140N or equal). Placement of gravel and filter fabric is also required for weep holes. The subdrain system behind the basement retaining walls will be located below the street level and will not drain via gravity. The subdrain water must be collected in a concrete catch basin and pumped to the street via sump-pumps. Each level of the subterranean parking must have a subdrain installed. The perforated subdrain pipes at various levels may be connected via vertical solid pipes. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 16 of 24

19 In addition, the retaining walls of the basement must be provided with extensive dampproofing. The damp-proofing must be designed by a water proofing specialist. As an alternative, the subterranean garage retaining walls may be provided with 12 x12 x12 gravel pockets, consisting of ¾ size gravel, spaced at 8-feet center-tocenter. These gravel pockets need to be placed in such a way between the two piles that each bay of the shoring/retaining wall system will contain at least one 12 x 12 x 12 gravel pocket. The gravel pocket may discharge the pore-water (if any) thru a 3 diameter solid PVC pipes (outlets) connected to the gravel pockets behind the wood lagging. The outlets must discharge the subdrain water a minimum of 1 above the finish floor levels. Please be advised that the recommended sub-drain system 12 x12 x12 gravel pocket is also available in a pre-fabricated PVC box form, made commercially; that can be used in this project as well. The box may be filled with ¾ size gravel before its placement into location, with one end containing the 3 -diameter solid PVC pipe outlet. A cross-section of a typical subdrain system using the 12 x12 x12 gravel pocket system is presented in Appendix A of this report. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 17 of 24

20 Seismic Parameters The seismic parameters for the design of the proposed structure based on the 2010 California Building Code are as follows: Latitude 34 o N Longitude 118 o W Site Classification D Site Coefficient, F a 1.0 Site Coefficient, F v 1.5 Site Spectral Response Acceleration Parameters (g): Mapped Acceleration, S S (0.2 sec.) Mapped Acceleration, S 1 (1 sec.) Adjusted Maximum Acceleration, S MS (0.2 sec.) Adjusted Maximum Acceleration, S M1 (1 sec.) Design Acceleration, S DS (0.2 sec.) Design Acceleration, S D1 (1 sec.) Conformance with the above listed criteria for seismic design does not constitute any kind of warranty, guarantee, or assurance that significant structural damage or ground failure will not occur if a maximum level earthquake occurs. The primary goal of seismic design is to protect life and limb, and to prevent catastrophic failures, and not to avoid all damage, since such design may be economically prohibitive. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 18 of 24

21 Seismic Hazard The subject property is shown on the State of California Seismic Hazard Zones map presented in Appendix C. The site is located outside of the seismically induced landslide and liquefaction hazard zone. Settlement Maximum total and differential settlements are expected to be less than one (1) and onehalf (½) inches, respectively, provided that our recommendations are followed. Engineered Fill All fill earth materials must consist of clean soil that is free of vegetation and other debris. The fill must be placed in six- (6-) to eight- (8-) inch thick lifts at near optimum moisture content and compacted. Particles larger than three (3) inches in diameter must not be allowed in the backfill material. Earth materials must not be imported to the site without prior approval by the soil engineer. All engineered fill must be compacted to a minimum of ninety (90) percent of its maximum dry density (ASTM D 1557). Where cohesionless soil having less than fifteen (15) percent finer than millimeter is used for fill, it must be compacted to a minimum of ninety-five (95) percent of its maximum dry density. Neither jetting nor water tamping are permitted. Heavy construction equipment must be maintained at a minimum distance of three (3) feet from the existing structures. Hand-operated compaction equipment must be used to compact the backfill soils within this 3-foot-wide zone. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 19 of 24

22 Concrete Slabs-on-Grade The subgrade for the proposed concrete slabs-on-grade must consist of undisturbed alluvium or two (2) foot thick layer of certified compacted fill. The competent subgrade must be covered with four (4) inches of crushed miscellaneous aggregate (CMA) and compacted to ninety-five percent (95%) of its maximum dry density (ASTM D 1557). The CMA must be covered with one (1) inch of sand. The sand must be covered by a ten (10)- mil vapor barrier. The vapor barrier must be installed so that the edges of the sheet overlap at least twelve (12) inches onto any adjacent sheet. The vapor barrier must be covered with one (1) inch of sand. The sand must be covered with four (4) inches of nonexpansive hard rock concrete mix (3/4" max. rock size). The reinforcement must be a minimum of #4 bars at sixteen (16) inches on center in both directions. The reinforcement must be placed at the mid-depth of the concrete slab. The slab must be covered with a vapor barrier for at least two (2) days to slow the curing time, reduce the shrinkage crack potential and be self-watering. The consulting structural-engineer-of-record may decide to increase the slab thickness according to the proposed traffic loads. Driveway The subgrade for the proposed driveway must consist of undisturbed alluvium or two (2) foot thick layer of certified compacted fill. The competent subgrade must be covered with four (4) inches of crushed miscellaneous aggregate (CMA) and compacted to ninety-five percent (95%) of its maximum dry density (ASTM D1557). The CMA must be covered by asphalt concrete, concrete slab, stone pavers or equal. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 20 of 24

23 Pipe Bedding and Trench Backfill The pipe bedding must consist of sand or similar granular material having a minimum sand equivalent value of thirty (30). The sand must be placed in a zone that extends a minimum of six (6) inches below and twelve (12) inches above the pipe for the full trench width. The bedding material must be compacted. The trench backfill above the pipe bedding may consist of approved, on-site or imported soils, and it must be compacted. Where utility trenches are parallel to the footings, the bottom of the trench must be located above a plane with a slope of 1:1, projected downward from the adjacent bottom edge of the footing. Site Drainage Drainage devices such as sloping sidewalks and area drains must be provided around the buildings to collect and direct all water away from the structures. Neither rain nor excess irrigation water should be allowed to collect or pond against foundations. The collected water must be directed to the proper drainage system via non-erosive devices. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 21 of 24

24 DESIGN REVIEW We suggest that the geotechnical aspects of the project be reviewed by this firm during the design process. The scope of our services may include assistance to the design team by providing specific recommendations for special cases, reviewing the foundation design, reviewing the geotechnical portions of the project for possible cost savings through alternative approaches, and evaluating the overall applicability of our recommendations. Additional site-specific explorations may also be considered if significant foundation modifications are required using the above recommendations. INECTION All excavations must be inspected and approved. All fill placed for engineering purposes must be tested for compaction and moisture content and certified. The subdrain system must be observed and approved. Inspection of excavations and subdrain system may also be required by the appropriate reviewing governmental agencies. It is recommended that SAS be retained to verify compliance with the recommendations made in this report, to ensure compliance with the design concepts, specifications, and recommendations, and to allow design changes in the event that exposed subsurface conditions differ from those anticipated herein. A joint meeting among the parties involved in this project is recommended prior to the start of groundbreaking to discuss specific procedures and scheduling. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 22 of 24

25 Inspections performed by SAS are for verification purposes only and shall under no circumstance relieve other parties involved in the design and construction from their obligation to perform work in accordance with the approved plans. In the event that the recommendations contained herein are interpreted by others, SAS will not accept responsibility for such interpretations. INVESTIGATION LIMITATIONS The conclusions and recommendations presented in this report are based on the findings and observations in the field and the results of laboratory tests performed on representative samples. The soils encountered in the boreholes and test pits are believed to be representative of the total area; however, soil characteristics can vary throughout the site. SAS should be notified if subsurface conditions are encountered which differ from those described in this report. This report has not been prepared for use by parties or projects other than those named and described above. It may not contain sufficient information for other parties or other purposes. The conclusions and recommendations presented in this report are professional opinions. These opinions have been derived in accordance with current standards of geotechnical engineering practice, field observations and laboratory test results. No other warranty is expressed or implied. Samples secured for this investigation will be retained in our laboratory for a period of thirty (30) days from the date of this report and will be disposed after this period unless other arrangements are made. SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 23 of 24

26 This report should be reviewed and updated after a period of one year or if the project concept changes from that described herein. We appreciate the opportunity to be of service to you. If you have any questions, please call our office. Sincerely, SASSAN GEOSCIENCES, INC. Sassan A. Salehipour, G.E. President SASSAN A G E O T. SA LEHIPOUR No Exp REGISTERED PROFESSIONA L ENGINEER E C H N L STATE OF CA LIFORNIA I C A SAS:ak/2fle045a3.doc Appendices SAS SASSAN Geosciences, Inc. 2FLE045 December 27, 2012 Page 24 of 24

27 REFERENCES: 1. California Division of Mines and Geology, 1998, Seismic Hazard Evaluation for the Hollywood 7.5 Minute Quadrangle, Los Angeles County, California; OFR California Division of Mines and Geology, 1999, Seismic Hazard Zones Map for the Hollywood Quadrangle, Los Angeles County, California; Scale 1:24, California Division of Mines and Geology, 1986, Official Map of Special Studies Zones, Hollywood Quadrangle; Scale 1:24, Dibblee, T.W., 1991, Geologic Map of the Hollywood and Burbank (South ½) Quadrangles, Los Angeles County, California. Dibblee Geological Foundation, Santa Barbara, California; Map DF-30; Scale 1:24,000

28 APPENDIX A

29 Site SAS VICINITY MAP FIGURE THE CITY MARKET OF LOS ANGELES A-1

30 TH-7 B-7 B-6 TH-6 B TH-4 A B-4 BUILDING (demolished) B-9 CANOPY/SHED (removed) B-3 BUILDING (demolished) CANOPY/SHED (removed) TH-9 1-STORY BUILDING W/ BASEMENT (demolished) A B-5 TH-5 TH-8 TH-2 TH-1 BUILDING (demolished) B-8 CANOPY/SHED (removed) B-2 CANOPY/SHED (removed) BUILDING (demolished) B-1 TH-3 B LEGEND SCALE: 1" = 120' SITE PLAN B-9 BOREHOLE NUMBER AND LOCATION TH-9 TEST HOLE NUMBER AND LOCATION FIGURE A-1

31 C/L P/L P/L C/L SECTION A-A SCALE: 1" = 120' FIGURE A-2

32 C/L P/L P/L C/L SECTION B-B SCALE: 1" = 120' FIGURE A-3

33 APPENDIX B

34 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS R SM 5 Description Pavement: 10" thick asphalt concrete Alluvium: Gray, damp to moist, medium dense, silty fine to medium sand, trace coarse sand, trace fine, subrounded gravel Light gray to light grayish brown, damp, dense, fine to coarse sand with fine to coarse, subangular gravel R Light grayish brown, moist, dense, fine to coarse sand, trace fine to medium, subrounded gravel Light gray to light grayish brown, damp, dense, fine to coarse sand with fine to coarse, subangular gravel; minor caving from 13' Same as above, but gray (salt and pepper) R Light grayish brown, moist, dense, fine to coarse sand, cobbles up to 6", trace fine to medium, subrounded gravel Same as above, but cobbles up to 8"; caving 25 Light grayish brown, moist, dense, medium to coarse sand with fine to coarse, subrounded gravel, trace fine sand; one 8" cobble; caving from 23' 30 R Excavation Terminated at Depth of 31 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF BORE HOLE NUMBER ONE (B-1) THE CITY MARKET OF LOS ANGELES FIGURE B-1

35 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM R-1 Description Pavement: 9" thick asphalt concrete Alluvium: Gray, damp to moist, medium dense, silty fine to medium sand, trace coarse sand, trace fine, subrounded gravel R Light gray to light grayish brown, damp, dense, fine to coarse sand with fine to coarse, subangular gravel 15 Light grayish brown, moist, dense, fine to medium sand, trace silt R Light grayish brown, moist, dense, fine to coarse sand, trace fine to medium, subrounded gravel; minor caving 25 Light grayish brown, moist, dense, medium to coarse sand with fine to coarse, subrounded gravel, trace fine sand; heavy caving from 24' R Light grayish brown, moist, dense, medium to coarse sand with fine to coarse, subrounded gravel, cobbles up to 6", trace fine sand Terminated at 32 feet due to caving Excavation Terminated at Depth of 32 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF BORE HOLE NUMBER TWO (B-2) THE CITY MARKET OF LOS ANGELES FIGURE B-2

36 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM 5 Description Pavement: 4" thick concrete slab Alluvium: Gray, damp to moist, medium dense, silty fine to medium sand, trace coarse sand, trace fine, subrounded gravel Light gray to light grayish brown, damp, dense, fine to coarse sand with fine to coarse, subangular gravel R Light grayish brown, moist, dense, medium to coarse sand with fine to coarse, subrounded gravel, trace fine sand Light grayish brown, moist, dense, medium to coarse sand with fine to coarse, subrounded gravel, cobbles up to 6", trace fine sand R R Same as above, but more gravel and cobbles; heavy caving Terminated at 35 feet due to caving 35 Excavation Terminated at Depth of 35 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF BORE HOLE NUMBER THREE (B-3) THE CITY MARKET OF LOS ANGELES FIGURE B-3

37 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM R-1 15 Description Pavement: 7" thick concrete slab Alluvium: Gray, damp to moist, medium dense, silty fine to medium sand, trace coarse sand, trace fine, subrounded gravel Light gray to light grayish brown, damp, dense, fine to coarse sand with fine to coarse, subangular gravel Light gray to light grayish brown, damp, dense, medium to coarse sand with fine to coarse, subangular gravel; cobbles up to 4", one 8" cobble; trace fine sand Light gray, moist, dense, medium to coarse sand with fine to medium, subangular gravel, trace fine sand; one large boulder at 13' R-2 R Light grayish brown, moist, dense, medium to coarse sand with fine to medium, subrounded gravel; caving Same as above, with fine to coarse, subrounded gravel; caving Terminated at 26 feet due to caving Excavation Terminated at Depth of 26 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF BORE HOLE NUMBER FOUR (B-4) THE CITY MARKET OF LOS ANGELES FIGURE B-4

38 Sample γ d Moisture Depth Description N Number ( pcf ) ( % ) ( ft ) 0 0-8" Asphalt 4"thick over 4" of base USCS R-1 S SM 2.5' FILL: Gray brown, moist, fine sand, trace silt, trace coarse 5' ALLUVIUM: Brown, moist, medium - coarse sand, trace silt R-2 S ' 10' moist Brown, medium - coarse gravelly sand, Brown, medium - coarse gravelly sand, S ' Brown, medium - coarse gravelly sand changes to silty sand few gravel, moist S ' moist Brown, medium - coarse gravelly sand, S ' Brown, interbeds of medium - coarse gravelly sand, and fine - medium sand with few gravels, moist Excavation Terminated at Depth of 25 Feet Water Seepage Was Not Encountered 40 R = Ring Sample; S = T sample SAS LOG OF BORE HOLE NUMBER FIVE (B-5) FIGURE THE CITY MARKET OF LOS ANGELES B-5

39 Sample γ d Moisture Depth Description N Number ( pcf ) ( % ) ( ft ) 0 0-3" Concrete slab over sandy silt 2.5' FILL: Brown, moist, fine - medium sandy silt, trace coarse sand 94 8 R-1 5' ALLUVIUM: Brown, moist, fine ML S-1 medium sandy silt, trace coarse sand 7.5' Brown, sandy silt changes to gray R-2 brown, medium - coarse gravelly sand, few 10 cobbles, moist ' Gray brown, medium - coarse gravelly S-2 sand, moist S ' sand, moist Gray Brown, medium - coarse gravelly 20' Gray Brown, medium - coarse gravelly S-4 sand, moist, cobbly S ' Gray Brown, medium - coarse gravelly sand, moist, cobbly Excavation Terminated at Depth of 25 Feet Water Seepage Was Not Encountered R = Ring Sample; S = T sample SAS 40 LOG OF BORE HOLE NUMBER SIX (B-6) FIGURE THE CITY MARKET OF LOS ANGELES B-6

40 Sample γ d Moisture Depth Description N Number ( pcf ) ( % ) ( ft ) " Asphalt 3.5" thick over 6" of base 2.5' FILL: Brown, moist, fine sandy silt, trace gravel 93 9 R-1 5 5' ALLUVIUM: Gray brown, moist, S-1 fine - medium sand, trace silt 7.5' Gray brown, moist, fine - medium sand 98 4 R-2 10' Gray brown, medium - coarse gravelly S-2 sand, moist 15' S-3 sand, moist Gray Brown, medium - coarse gravelly 20' S-4 sand, moist Gray Brown, medium - coarse gravell y 25' Gray Brown, medium - coarse gravelly S-5 sand changes to fine sandy silt, moist Excavation Terminated at Depth of 25 Feet Water Seepage Was Not Encountered R = Ring Sample; S = T sample SAS 40 LOG OF BORE HOLE NUMBER SEVEN (B-7) FIGURE THE CITY MARKET OF LOS ANGELES B-7

41 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS ML S-1 Description 0-6" Concrete slab 6" thick over sandy silt ALLUVIUM: Gray brown, moist, fine sandy 5' Gray brown, moist, fine sandy silt changes to fine - medium sand 10' Gray brown, medium - coarse gravelly S-2 sand, moist, few cobbles R ' Gray Brown, fine - medium sand, moist 20' S-3 sand, moist Gray Brown, medium - coarse gravelly R ML/SM 25' Brown, wet, sandy silt changes to fine - medium silty sand, trace gravel S ' Gray Brown, medium - coarse gravelly sand, moist, rocky, difficult drilling R ' Gray Brown, medium - coarse gravelly sand, moist, rocky, difficult drilling 40 R = Ring Sample; S = T sample SAS LOG OF BORE HOLE NUMBER EIGHT (B-8) THE CITY MARKET OF LOS ANGELES FIGURE B-8(a)

42 Sample γ d Moisture Depth Description N Number ( pcf ) ( % ) ( ft ) /6" 40' Gray Brown, medium - coarse gravelly S-5 sand, moist, with cobbles, difficult drilling USCS 45 50' Brown, moist, clayey silt with gravel, /6" S-6 cobbly, very tight, diffcult to drill ML 55 S /6" 60' Greenish Brown, moist, sandy silt, trace clay; changes to medium - coarse gravelly sand, rocky, difficult drilling 65 S /6" 70' Gray Brown, medium - coarse gravelly sand, moist, rocky, difficult drilling 75 Excavation Terminated at Depth of 70 Feet Water Seepage Was Not Encountered 80 R = Ring Sample; S = T sample SAS LOG OF BORE HOLE NUMBER EIGHT (B-8) THE CITY MARKET OF LOS ANGELES FIGURE B-8(b)

43 Sample γ d Moisture Depth Description N Number ( pcf ) ( % ) ( ft ) 0 0-6" Asphalt 10" thick over sandy silt ALLUVIUM: Gray brown, moist, fine sandy silt changes to fine - medium sand USCS ML/SM 5' Gray brown, moist, fine sandy silt changes to fine - medium sand S ' Gray brown, medium - coarse gravelly sand, moist, few cobbles 15' R-1 trace silt Gray brown, fine - medium sand, moist, 20' S-2 moist Gray Brown, medium - coarse sand, R ' moist Gray Brown, medium - coarse sand, 30' S-3 sand, moist Gray Brown, medium - coarse gravelly R ' Gray Brown, medium - coarse gravelly sand, moist 40 R = Ring Sample; S = T sample SAS LOG OF BORE HOLE NUMBER NINE (B-9) THE CITY MARKET OF LOS ANGELES FIGURE B-9(a)

44 Sample γ d Moisture Depth Description N Number ( pcf ) ( % ) ( ft ) ' Gray Brown, medium - coarse gravelly S-4 sand, moist USCS 45 50' Gray Brown, medium - coarse gravelly /6" S-5 sand, moist, rocky, difficult to drill 55 60' Gray Brown, medium - coarse gravelly /6" S-6 sand, moist, rocky, difficult to drill 65 70' Gray Brown, medium - coarse gravelly /6" S-7 sand, moist, rocky, difficult drilling 75 Excavation Terminated at Depth of 70 Feet Water Seepage Was Not Encountered 80 R = Ring Sample; S = T sample SAS LOG OF BORE HOLE NUMBER NINE (B-9) THE CITY MARKET OF LOS ANGELES FIGURE B-9(b)

45 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM Description Pavement: 6" thick asphalt concrete Alluvium: Brown, moist, silty fine to medium sand SM 5 10 Light brown, moist, fine to medium sand, trace gravel Light brown, moist, gravelly medium to coarse sand with cobbles 4" to 6" 15 R R R Excavation Terminated at Depth of 33 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER ONE (TH-1) THE CITY MARKET OF LOS ANGELES FIGURE B-10

46 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM Description Pavement: 6" thick asphalt concrete Alluvium: Brown, moist, silty fine to medium sand SM/ 5 Interbedded silty sand and gravelly medium to coarse sand with cobbles, moist 10 Gravelly medium to coarse sand with cobbles, moist 15 R Same as above with cobbles 6" to 8" R R Excavation Terminated at Depth of 30 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER TWO (TH-2) THE CITY MARKET OF LOS ANGELES FIGURE B-11

47 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 SM USCS SM 5 Description Pavement: 4" thick asphalt concrete Fill: Brown, moist, silty fine to medium sand Alluvium: Brown, moist, silty fine to medium sand Light brown, moist, gravelly medium to coarse sand with cobbles up to 9"; number of cobbles increasing with depth R Same as above with boulders 12" to 15" R R Excavation Terminated at Depth of 30 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER THREE (TH-3) THE CITY MARKET OF LOS ANGELES FIGURE B-12

48 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM Description Pavement: 8" thick asphalt concrete Fill: Brown, moist, silty fine to medium sand SM 5 Alluvium: Brown, moist, silty fine to medium sand SM 10 Light brown, moist, fine to medium sand with trace gravel and few cobbles Light brown, moist, gravelly medium to coarse sand 15 R ML 20 Layer of clayey silt/sandy silt Light brown, moist, gravelly medium to coarse sand R R Excavation Terminated at Depth of 32 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER FOUR (TH-4) THE CITY MARKET OF LOS ANGELES FIGURE B-13

49 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 SM USCS SM 5 SM/ 10 Description Pavement: 6" thick asphalt concrete Fill: Brown, moist, silty fine to medium sand Alluvium: Brown, moist, silty fine to medium sand Interbedded silty sand and gravelly medium to coarse sand with cobbles, moist Gravelly medium to coarse sand with cobbles, moist 15 R R R Excavation Terminated at Depth of 36 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER FIVE (TH-5) THE CITY MARKET OF LOS ANGELES FIGURE B-14

50 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 SM USCS SM 5 Description Pavement: 6" thick asphalt concrete Fill: Brown, moist, silty fine to medium sand Alluvium: Brown, moist, silty fine to medium sand Light brown, moist, gravelly medium to coarse sand R R R Medium to coarse sandy gravel with boulders GP 35 Excavation Terminated at Depth of 40 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER SIX (TH-6) THE CITY MARKET OF LOS ANGELES FIGURE B-15

51 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS ML Description Pavement: 6" thick asphalt concrete Fill: Brown, moist, fine to medium sandy silt ML 5 Alluvium: Brown, moist, fine to medium sandy silt Gravelly fine to coarse sand R R R Excavation Terminated at Depth of 35 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER SEVEN (TH-7) THE CITY MARKET OF LOS ANGELES FIGURE B-16

52 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM 5 Description Pavement: 6" thick asphalt concrete Fill: Brown, moist, fine to medium silty sand Alluvium: Light brown, moist, gravelly medium to coarse sand and sandy gravel 10 /GP 15 R R Light brown, wet, gravelly medium to coarse sand Excavation Terminated at Depth of 33 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER EIGHT (TH-8) THE CITY MARKET OF LOS ANGELES FIGURE B-17

53 Sample γ d Moisture Depth N Number ( pcf ) ( % ) ( ft ) 0 USCS SM 5 Description Pavement: 4" thick concrete slab Alluvium: Gray, damp to moist, silty fine to medium sand, trace gravel Light brown, damp, fine to coarse sand with gravel R Light brown, moist, fine to coarse sand with gravel, cobbles up to 6" R Excavation Terminated at Depth of 38 Feet Water Seepage Was Not Encountered R = Ring Sample SAS 40 LOG OF TEST HOLE NUMBER NINE (TH-9) THE CITY MARKET OF LOS ANGELES FIGURE B-18

54 APPENDIX C

55 Site SAS CALIFORNIA SEISMIC HAZARD ZONES MAP FIGURE THE CITY MARKET OF LOS ANGELES C-1

56 Site SAS Department of Conservation, Division of Mines And Geology Seismic Hazard Evaluation of The Hollywood 7.5-Minute Quadrangle, Los Angeles County, California, 1998, OFR HISTORICALLY HIGHEST GROUND WATER LEVELS FIGURE THE CITY MARKET OF LOS ANGELES C-1

57 APPENDIX D

58 Site SAS Dibblee, T.W., Jr., Dibblee Geological Foundation, Geologic Map of Hollywood and Burbank (South ½) Quadrangles, 1991, Map # DF-30 GEOLOGIC MAP FIGURE THE CITY MARKET OF LOS ANGELES D-1