IV. Environmental Impact Analysis D. Geology and Soils

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1 IV. Environmental Impact Analysis D. Geology and Soils 1. Introduction This section evaluates geologic and soils hazards that could potentially result due to implementation of the proposed project. Geologic and soil issues analyzed include surface fault rupture, ground shaking, ground failure, liquefaction, landslides, mudflows, and subsidence of the land. The information and findings in this section are based on the Geotechnical Engineering Investigation (geotechnical report) dated June 6, 2002 and Addendum I, Additional Exploration, dated March 17, 2003, both prepared by Geotechnologies, Inc. These reports are provided as Appendix C in this Draft EIR. 2. Environmental Setting a. Existing Conditions (1) Regional Setting The project site is located in the San Fernando Valley, north of the Peninsular Ranges Geomorphic Province and within the Transverse Ranges Geomorphic Province. The Peninsular Ranges Province is characterized by northwest trending ranges and valleys that extend south from the Los Angeles Basin into Baja California. The Peninsular Ranges extend approximately 80 miles offshore to the west and are truncated on the north by the Western and Central Transverse Ranges, an east-west trending series of mountains including the Santa Monica and San Gabriel Mountains. (2) Soil Conditions The project site slopes gently downward to the north, with a relatively flat topography varying between feet and feet above mean sea level. Geologic explorations identified the presence of fill material consisting of moist, medium dense to dense, silty sands with minor organics and construction debris up to a depth of 5 feet below ground surface (bgs). Native soils consist predominantly of clayey silts and silty clays deposited by river and stream action, in excess of 200 feet bgs. Groundwater was encountered at Page IV.D-1

2 depths between 43 feet and 46.5 feet bgs, with the highest groundwater elevation located near the southwest corner of the project site. Expansive soils result from the presence of swelling clay minerals. As they get wet, the clay minerals absorb water molecules and expand; conversely, as they dry they shrink, leaving large voids in the soil. Soils beneath the site were determined to be in the low to moderate expansion range. (3) Seismic Hazards (a) Faulting and Ground Shaking Faults may be characterized as active, potentially active, or inactive based on criteria established by the California Geological Survey (CGS). Active faults are those that have shown evidence of surface displacement within the past 11,000 years (i.e., Holocene time). 1 Potentially active faults are those that have shown evidence of most recent surface displacement within the past 1.6 million years (i.e., the Quaternary age). Faults showing no evidence of surface displacement within the last 1.6 million years are considered inactive for most purposes, but are taken into account in the design of some critical structures. In addition, there are buried thrust faults, which are low angle reverse faults with no surface exposure. Buried thrust faults are typically broadly defined based on the analysis of seismic wave recordings of several hundred small earthquakes in the southern California area. The CGS establishes regulatory zones around active faults, called Alquist-Priolo Earthquake Fault Zones (formerly Special Study Zones). These zones, which extend from 200 to 500 feet on each side of the known active fault, identify areas where potential surface rupture along an active fault could prove hazardous and identify where special studies are required to characterize hazards to habitable structures. In addition, the City of Los Angeles designates Fault Rupture Study Zones extending along each side of active and potentially active faults to establish areas of hazard potential due to fault rupture. 2 No known active or potentially faults underlie the project site. Therefore, the project site is not located within an Alquist-Priolo Earthquake Fault Zone or City-designated Fault Rupture Study Zones. 1 2 California Department of Conservation, California Geologic Survey, Special Publication 42: Fault Rupture Hazard Zones in California, General Plan Safety Element, Exhibit A, adopted by the City Council, November 26, Page IV.D-2

3 Figure IV.D-1 on page IV.D-4 shows the location of the project site with respect to various faults within the region. The closest active fault to the project site is the Northridge (East Oak Ridge) Fault, which is located approximately 5.2 miles to the north. The Hollywood Fault, the Santa Monica Fault, the Verdugo Fault, and the Malibu Coast Fault are also within 10 miles of the project site. The historic seismic record indicates that 70 earthquakes of magnitude 5.0 and greater have occurred within 60 miles of the project site between the years 1800 and Two major buried thrust faults in the Los Angeles area are the Elysian Park fold and thrust belt and the Torrance-Wilmington fold thrust belt. It is believed the Elysian Park fold and thrust belt was responsible for the magnitude 5.9 Whittier Narrows earthquake on October 1, 1987 and the Torrance-Wilmington fold thrust belt was responsible for the magnitude 5.0 Malibu earthquake on January 19, It is also believed that the magnitude 6.7 Northridge earthquake on January 17, 1994 was caused by a still unnamed buried thrust fault located beneath the San Fernando Valley. (b) Liquefaction Liquefaction is a seismic phenomenon in which loose, saturated, fine-grained granular soils behave like fluid when subjected to high-intensity ground shaking, as caused by an earthquake. Liquefaction generally occurs when all three conditions exist: shallow groundwater; low density, fine, clean sandy soils; and high density ground motion. The effects of liquefaction at ground level can include loss of bearing strength, ground oscillations, lateral spreading, and flow failures. The project site is located within a delineated liquefaction hazard zone as indicated by the CGS Seismic Hazards Map. This determination is based on groundwater depth records, soil type, and distance to a fault capable of producing a substantial earthquake. In addition, the project site is designated as a liquefiable area by Exhibit B of the City s Safety Element of the General Plan. (c) Inundation by Seiches and Dam Failures Seiches are waves formed from oscillations in enclosed or partially enclosed bodies of water caused by displacement within the water bodies or sustained earthquake motions. The displacement of water could result in seismically-induced flooding, allowing water to flow downstream unabated at higher-than-normal volumes. Dam failures could also result in inundation of areas located downstream. The project site lies within the inundation hazard areas of the Encino Reservoir, which is located approximately 2.5 miles westsouthwest of the site, and the Sepulveda Dam, located approximately 0.7 mile to the northwest. Page IV.D-3

4 Source: U.S.G.S Data 1994 Fault Activity DMG Open-File report by C. Jennings and Matrix Environmental, 2009 Figure IV.D-1 Major Regional Faults Page IV.D-4 Page _

5 (d) Seismically-Induced Landslides Landslides tend to occur in loosely consolidated, wet soil and/or rock on unstable sloping terrain. The project site is characterized by a relatively flat topography, as discussed above. Accordingly, the project site is not classified as a landslide hazard zone on the CGS Seismic Hazards Map. In addition, the City does not identify the project site in its inventory of landslide and hillside areas. 3 As such, the potential for landslides occurring on the project site is low. Therefore, this issue will not be discussed or analyzed further. (e) Subsidence Subsidence is a localized mass movement that involves the gradual downhill settling or sinking of the earth s surface, resulting from the extraction of mineral resources, subsurface oil, groundwater, or other subsurface liquids, such as natural gas. The principal cause of subsidence is the extraction of subsurface liquids. The project site is not located in area where the withdrawal of oil or water is occurring. Furthermore, the lowest level of the project s subterranean parking structure would be approximately 17 feet above the highest groundwater table. Although perched water layers have been previously encountered and casting or polymer-slurry drilling fluid could be necessary for pile excavations, no dewatering activities would be necessary during construction. As such, the probability of subsidence occurring on the project site is low. Therefore, this issue will not be discussed or analyzed further. (f) Tsunamis Tsunamis are large ocean waves generated by large-scale, short duration submarine earthquakes. Tsunami waves are capable of traveling great distances and damaging lowlying coastal regions. The project site is located approximately 10 miles inland from the Pacific Ocean at elevations ranging from approximately feet to feet above mean sea level. As such, the probability of a tsunami impacting the project site is considered low. Therefore, this issue will not be discussed or analyzed further. (4) Mineral Resources Mineral resource zones (MRZ-2) in the City identify areas where adequate information indicates that significant mineral deposits are present or where it is judged that a high likelihood for their presence exists. MRZ-2 areas are significant because of their 3, Department of City Planning, Los Angeles Citywide General Plan Framework, Draft Environmental Impact Report, January 19, 1995, Figure GS-4. Page IV.D-5

6 potential for sand and gravel extraction. These areas are located primarily from the northeast and east San Fernando Valley to the Los Angeles Basin (adjacent to the I-5 Freeway), as well as along the current and ancestral Los Angeles River through downtown into South Central Los Angeles, none of which incorporates the project site. 4 As such, the probability of the loss of access to a mineral resource as a result of the project is considered very low. Therefore, this issue will not be discussed or analyzed further. b. Regulatory Framework (1) State (a) Alquist-Priolo Earthquake Fault Zoning Act The Alquist-Priolo Geologic Hazards Zone Act (California Public Resources Code Sections ) was enacted by the State of California in 1972 to address the hazard and damage caused by surface fault rupture during an earthquake. The Act has been amended ten times and renamed the Alquist-Priolo Earthquake Fault Zoning Act, effective January 1, The Act requires the CGS to establish Alquist-Priolo Earthquake Fault Zones (previously called Special Study Zones) along known active faults in the state. As discussed above, these zones extend from 200 to 500 feet on each side of the known fault and identify areas where potential surface fault rupture could prove hazardous for buildings used for human occupancy. Cities and counties that include earthquake fault zones are required to regulate development projects within these zones. (b) Seismic Hazard Mapping Act The Seismic Hazard Mapping Act of 1990 (California Public Resources Code Sections ) was enacted, in part, to address seismic hazards not included in the Alquist-Priolo Act, including strong ground shaking, landslides, and liquefaction. Under this Act, the State Geologist is assigned the responsibility of identifying and mapping seismic hazards zones to local governments in planning and developing. (c) Seismic Safety Commission Act and the California Earthquake Hazards Reduction Act The California Seismic Safety Commission was established by the Seismic Safety Commission Act (California Government Code Sections ) in This 4, Department of City Planning, Los Angeles Citywide General Plan Framework, Draft Environmental Impact Report, January 19, 1995, Figure GS-1. Page IV.D-6

7 statute requires the Seismic Safety Commission to prepare and administer a program setting forth priorities, funding sources, amounts, schedules, and other resources needed to reduce statewide earthquake hazards significantly by the year California Seismic Safety Commission presents the program required by the 1985 California Earthquake Hazards Reduction Act in a series of five-year Plans. The California Earthquake Loss Reduction Plan incorporates updates from information obtained from more recent large seismic events, including the Loma Prieta (1989), Northridge (1994), and Kobe, Japan (1995) earthquakes. This version of the Plan fulfills several needs: 1) it continues to be the Commission s policy statement about what needs to be done to reduce earthquake risk over the long term; 2) it serves as the State s strategic plan, guiding the executive and legislative branches in overall implementation strategies and priorities for seismic safety; and 3) it complies with the Federal Emergency Management Agency s (FEMA s) National Hazards Mitigation Strategy and is the State s hazard mitigation plan required for federal mitigation funding after earthquakes. 5 The Plan emphasizes the importance of upgrading existing vulnerable structures, better design of new construction, and increased preparedness in all areas as the most cost-effective methods of reducing loss and improving recovery from earthquakes. (d) California Geological Survey The CGS also provides guidance with regard to seismic hazards. The CGS s Special Publication 117, Guidelines for Evaluating and Mitigating Seismic Hazards in California provides guidance for evaluation and mitigation of earthquake-related hazards for projects within designated zones of required investigation. The intent of this publication is to protect the public from the effects of strong ground shaking, liquefaction, landslides, or other ground failure, and other hazards caused by earthquakes. (e) California Division of Safety of Dams The California Division of Safety of Dams regulates the inspection, maintenance and repair of dams in the State. 6 The California Water Code, Division 3, Dams and Reservoirs, states that the Division of Safety of Dams is charged with the authority to supervise the maintenance and operation of dams and reservoirs insofar as necessary to safeguard life and property from injury by dam failure. In addition, this division of the Water Code 5 6 California Seismic Safety Commission, California Earthquake Loss Reduction Plan , July 2007., Department of City Planning, Los Angeles Citywide General Plan Framework, Draft Environmental Impact Report, January 19, 1995, Page Page IV.D-7

8 identifies the frequency of dam inspections and emergency measures to be taken in the event of a disaster such as flooding. (f) California Building Code The California Building Code (CBC) [California Code of Regulations (CCR), Title 24 (California Building Code [CBC]) is a compilation of building standards, including seismic safety standards for new buildings. CBC standards are based on building standards that have been adopted by state agencies without change from a national model code; building standards based on a national model code that have been changed to address particular California conditions; and building standards authorized by the California legislature but not covered by the national model code. Given the State s susceptibility to seismic events, the seismic standards within the CBC are among the strictest in the world. The CBC applies to all occupancies in California, except where stricter standards have been adopted by local agencies. The State adopted the 2007 CBC, which became effective on January 1, Specific CBC building and seismic safety regulations have been incorporated by reference in the Los Angeles Municipal Code with local amendments. (2) Local (a) Safety Element The Safety Element of the General Plan (1996) addresses public safety risks due to natural disasters such as earthquakes, and also sets forth guidance for emergency response during such disaster events. The Safety Element provides maps of designated areas within the City that are considered susceptible to earthquake-induced hazards, such as Fault Rupture Zones, liquefaction, and landslides (discussed previously). (b) Los Angeles Municipal Code Earthwork activities, including grading, are governed by the Los Angeles Building Code (LABC), which is contained in Los Angeles Municipal Code (LAMC), Chapter IX, Article 1. Specifically, Section includes requirements regarding import and export of material; Section includes regulations pertaining to excavations; Section includes requirements for fill materials; Section includes regulations pertaining to erosion control and drainage devices; Section , Construction Requirements and Limitations, includes general construction requirements as well as requirements regarding flood and mudflow protection; and Section includes regulations for areas that are subject to slides and unstable soils. Page IV.D-8

9 Additionally, the LABC includes specific requirements addressing seismic design, slope stability, grading, foundation design, geologic investigations and reports, soil and rock testing, and groundwater. The LABC incorporates by reference the CBC, with City amendments for additional requirements. The City Department of Building and Safety is responsible for implementing the provisions of the LABC. 3. Environmental Impacts a. Methodology An assessment of grading, site design, and seismicity was performed to identify potential project impacts associated with geology and soils. As indicated above, the analysis is based on the Geotechnical Engineering Investigation and Addendum I, which were prepared by Geotechnologies, Inc. and are included as Appendix C of this Draft EIR. The geotechnical reports were prepared based on review of existing documentation, field investigations including subsurface exploration, and laboratory testing. b. Thresholds of Significance Appendix G of the CEQA Guidelines provides a set of sample questions that address impacts with regard to geology and soils. These questions are as follows: Would the project: Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving: o Rupture of a known earthquake fault, as delineated on the most recent Alquist-Priolo Earthquake Fault Zoning Map issued by the State Geologist for the area based on other substantial evidence of a known fault? Refer to Division of Mines and Geology Special Publication 42. o Strong seismic ground shaking? o Seismic-related ground failure, including liquefaction? o Landslides? Result in substantial soil erosion or the loss of topsoil? Be located on a geologic unit or soil that is unstable, or that would become unstable as a result of the project, and potentially result in on- or off-site landslide, lateral spreading, subsidence, liquefaction, or collapse? Page IV.D-9

10 Be located on expansive soil, as defined in Table 18-1-B of the Uniform Building Code (1994), creating substantial risks to life or property? Have soils incapable of adequately supporting the use of septic tanks or alternative waste water disposal systems where sewers are not available for the disposal of waste water? In the context of these questions from Appendix G of the CEQA Guidelines, the City of Los Angeles CEQA Thresholds Guide states that a project would normally have a significant geology and soils impact if the project would: (1) Geologic Hazards Cause or accelerate geologic hazards, which would result in substantial damage to structures or infrastructure, or expose people to substantial risk of injury. (2) Sedimentation and Erosion Constitute a geologic hazard to other properties by accelerating instability from erosion; or Accelerate natural processes of wind and water erosion and sedimentation, resulting in sediment runoff or deposition which would not be contained or controlled on-site. (3) Landform Alteration One or more distinct and prominent geologic or topographic features would be destroyed, permanently covered, or materially and adversely modified. Such features may include, but are not limited to, hilltops, ridges, hillslopes, canyons, ravines, rock outcrops, water bodies, streambeds, and wetlands. c. Project Features As described in greater detail in Section II, Project Description, the proposed project would include the development of 500 multi-family residential units and approximately 55,000 square feet of neighborhood-serving commercial uses within a series of six-story buildings, located on top of a structural podium. Parking for the project would be provided within an enclosed parking podium (beneath the residential uses) that would include two subterranean levels, one ground level, and one mezzanine level. The bottom subterranean level of the parking structure would have a finished floor elevation of 15.5 to 23.5 feet bgs. Project construction would require approximately 165,000 cubic yards of grading and soil Page IV.D-10

11 export. Activities associated with the grading and export of soil would occur in accordance with City requirements, as specified in the LAMC and through the grading plan review and approval process. d. Analysis of Project Impacts (1) Soil Conditions Since the parking structure would have a finished floor elevation of up to 23.5 feet bgs, the project would require the removal of all existing fill materials and some native soils beneath the project site. As discussed previously, project construction would require approximately 165,000 cubic yards of grading and soil export. Erosion and sedimentation from exposed soils could occur during construction. However, project construction activities would be conducted in compliance with erosion control measures, including grading and dust control measures, imposed by the City pursuant to grading permit regulations. Specifically, project construction would comply with LAMC Chapter IX, which requires necessary permits, plans, plan checks, and inspections to reduce the effects of sedimentation and erosion. In addition, the project would be required to have an erosion control plan approved by the Department of Building and Safety, as well as a Storm Water Pollution Plan (SWPPP) pursuant to the National Pollutant Discharge Elimination System (NPDES) permit requirements. As part of the SWPPP, Best Management Practices (BMPs) would be implemented during construction to reduce soil erosion and pollutant levels to the maximum extent possible. As such, construction of the project would not constitute a geologic hazard to other properties by accelerating instability from erosion or accelerating the natural processes of wind and water erosion and sedimentation that would result in sediment runoff or deposition that would not be contained or controlled on-site. Therefore, construction-related impacts associated with erosion and sedimentation would be less than significant. With the exception of one single-family residence on the project site, the project site is currently graded and vacant. Implementation of the project would replace the residence and existing graded areas with new structures, paving, and landscaping. Therefore, soil erosion and sedimentation effects during operation would be less as compared with existing conditions. In addition, Standard Urban Stormwater Mitigation Plan (SUSMP) provisions that would include site-specific BMPs would be implemented throughout the operational life of the project, which would assist in reducing on-site erosion. As such, operation of the project would not constitute a geologic hazard to other properties by accelerating instability from erosion or accelerating the natural processes of wind and water erosion and sedimentation that would result in sediment runoff or deposition that would not be contained or controlled on-site. Therefore, operational impacts associated with erosion Page IV.D-11

12 and sedimentation would be less than significant. Refer to Section IV.F, Hydrology and Water Quality, of this Draft EIR for additional information regarding erosion control. As recommended in the geotechnical report prepared for the project, the project s proposed six-story structures would be founded on a system of driven concrete piles and/or drilled cast-in-place piles, bearing in the dense native soil. The geotechnical report prepared for the project was found to be acceptable by the Department of Building and Safety (LADBS), provided that the conditions specified therein are complied with during site development. 7 Thus, with implementation of the geotechnical report s recommendations as set forth in the mitigation measure (discussed below), the project would not cause or accelerate geologic hazards that would result in substantial damage to structures or infrastructure or expose people to substantial risk of injury. With implementation of the mitigation measure, geologic hazard impacts related to soil instability would be reduced to less than significant levels. With regard to landform alteration, the project site is located in an urbanized area and is currently graded. As no distinct or prominent geologic or topographic features would be destroyed, permanently covered, or materially and adversely modified as a result of the project, impacts related to landform alteration would be less than significant. (2) Seismic Hazards (a) Faulting and Groundshaking As discussed above, no known active or potentially active faults pass through the project site. Therefore, the project site is not located within an Alquist-Priolo Earthquake Fault Zone or a City-designated Fault Rupture Study Zone, and the potential for surface ground rupture at the project site is considered low. 8 However, the project site is located in the seismically active region of southern California. Seismic exposure for the project site was analyzed in the geotechnical report using two methods, the deterministic method and the probabilistic method. The deterministic method calculates the maximum ground motion based on the maximum magnitude that a particular fault can produce. Based on this method, the maximum 7 8 Department of Building and Safety, Soil Report Approval Letter for Vesting Tract Map 61216, lots 1 to 5, 4827 Sepulveda Boulevard, January 26, 2005., Department of City Planning, Los Angeles Citywide General Plan Framework, Draft Environmental Impact Report, January 19, 1995, Figure GS-8. Page IV.D-12

13 earthquake resulting in the largest estimated maximum earthquake site acceleration at the site would be a magnitude 6.9 event on the Northridge Fault. This event would be expected to generate peak horizontal accelerations at the project site of 0.75 g (0.75 times the acceleration of gravity). The probabilistic method calculates the maximum ground motion based on the probability that a 10 percent earthquake (i.e., earthquake with a return period of 475 years) and a 50 percent earthquake (i.e., earthquake with a return period of 72 years) would occur. 9 Based on the probabilistic method, the project site would be subject to mean accelerations of 0.66 g and 0.34 g during a 10 percent and 50 percent earthquake, respectively. In order to minimize seismic hazards, the project would be designed and constructed in accordance with State and local building and safety codes, including the seismic safety requirements contained in the CBC and the LABC. In addition, the project would adhere to the safety guidelines provided in CGS s Special Publications 117, Guidelines for Evaluating and Mitigating Seismic Hazards in California and the project design recommendations set forth in the geotechnical report regarding support on a system of driven concrete piles and/or drilled, cast-in-place friction piles; shoring; installation of retaining walls for the proposed subterranean levels of the parking structure; waterproofing; and retaining wall drainage. To ensure that the project would adhere to applicable safety requirements and that the project would not cause or accelerate geologic hazards that would result in substantial damage to structures or infrastructure or expose people to substantial risk of injury, a mitigation measure is provided below. With implementation of the mitigation measure, potential impacts associated with strong seismic ground shaking would be reduced to less than significant levels. (b) Liquefaction As indicated above, the project is located within a State-designated and Citydesignated liquefaction zone. However, liquefaction tests indicate that soil beneath the project site would not be prone to liquefaction during a 10 percent earthquake (e.g. earthquake with a 475-year return period). Furthermore, the project would comply with State and local building and safety codes, including the CBC, and the LABC. In 9 The level of earthquake chosen as the basis for assessing seismic risk is usually measured in terms of estimated return period (i.e., the mean time among seismic events of equal or similar characteristics). The return periods commonly used are 72-, 475-, and 975-year periods. These return periods correspond to 50, 10, and 5 percent probability of seismic occurrence for a 50-year period, which is the expected design life for a building. The 475-year return period, or 10 percent probability of seismic occurrence in 50 years, is the most common standard used in the industry for assessing seismic risk, and it is also the basis for most building codes for seismic design. (International Risk Management Design, Understanding the Language of Seismic Risk Analysis, July 2003.) Page IV.D-13

14 addition, the project would comply with the safety guidelines set forth in CGS Special Publications 117, Guidelines for Evaluating and Mitigating Seismic Hazards in California and the project design recommendations set forth in the geotechnical report. The LADBS indicated that due to the improbability of liquefaction on the project site, no mitigation is necessary pursuant to the Seismic Hazard Mapping Act. 10 Therefore, the project would not cause or accelerate geologic hazards which would result in substantial damage to structures or infrastructure or expose people to substantial risk of injury and geologic hazard. Impacts related to liquefaction would be less than significant. (c) Inundation by Seiches and Dam Failures As stated above, the project site lies within the inundation hazard areas of the Encino Reservoir and the Sepulveda Dam, which are managed by the Los Angeles Department of Water and Power. It is possible that overtopping of the reservoir and/or dam could occur with a worst-case scenario, leading to dam failure. Seismic activity could also lead to failure of either of these water containment structures. According to the City, dam safety regulations are the primary means of reducing damage or injury due to inundation occurring from dam failure. 11 The California Division of Safety of Dams regulates the siting, design, construction, and periodic review of all dams in the State. Mitigation of potential seiche hazards has also been implemented by the Los Angeles Department of Water and Power through regulation of the level of water in its storage facilities and the provision of walls of extra height to contain seiches and prevent overflow or inundation. Dams and reservoirs are monitored during storms, and measures are instituted in the event of potential overflow. These measures apply to facilities within the City s borders and facilities owned and operated by the City within other jurisdictions. 12 Further, the Sepulveda Dam has automatically controlled spillway gates that rise and lower to control the dam from overtopping. 13 Automatic release of water from the dam is discharged to the Los Angeles River. In addition, the I-405 and US-101 Freeways serve as physical barriers between the Encino Reservoir, the Sepulveda Dam, and the project site. Therefore, the project would not cause or accelerate geologic hazards which would result in substantial damage to 10 Department of Building and Safety, Soil Report Approval Letter for Vesting Tract Map 61216, lots 1 to 5, 4827 Sepulveda Boulevard, January 26, , Department of City Planning, Los Angeles Citywide General Plan Framework, Draft Environmental Impact Report, January 19, 1995, pages and , Department of City Planning, Safety Element of the Los Angeles General Plan, Adopted by the City Council November 26, 1996, page II United States Army Corps of Engineers, Los Angeles District, Reservoir Regulation Section, Accessed July 22, Page IV.D-14

15 structures or infrastructure; or expose people to substantial risk of injury due to inundation by a dam or a seiche. Impacts related to these issues would be less than significant. 4. Cumulative Impacts Impacts associated with geologic and soil issues are typically confined to a project site or within a very localized area and do not affect off-site areas associated with related projects or ambient growth. Cumulative development in the area would, however, increase the overall potential for exposure to seismic hazards by potentially increasing the number of people exposed to seismic hazards. Nevertheless, all related projects would be subject to established guidelines and regulations pertaining to seismic hazards. As such, adherence to applicable building regulations and standard engineering practices would ensure that cumulative geology impacts would be less than significant. 5. Mitigation Measures The following mitigation measure is proposed to reduce the project s potential geotechnical impacts to less than significant levels: Mitigation Measure D-1: The Applicant or its contractor shall incorporate the recommendations detailed in the geotechnical investigation prepared for the proposed project, as approved by the. (Geotechnical recommendations regarding pile or drill caissons, footings, slabs, fill, shoring, retaining walls, and site drainage are provided within the Geotechnical Engineering Investigation (geotechnical report) dated June 6, 2002 and Addendum I, Additional Exploration, dated March 17, 2003, both prepared by Geotechnologies, Inc. provided in Appendix C of this Draft EIR.) 6. Level of Significance After Mitigation With implementation of the recommended mitigation measure, impacts associated with geology and soils would be reduced to less than significant levels. Page IV.D-15