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Iv. Environmental Impact Analysis D. Geology & Soils IV. ENVIRONMENTAL IMPACT ANALYSIS D. GEOLOGY & SOILS 1. INTRODUCTION This Section describes the geologic conditions at and near the project site and identifies the types of geotechnical hazards associated with development of the project site. The following analysis is based upon the Summary of Preliminary Geotechnical Feasibility Evaluation dated March 15, 2007, prepared by Moore Twining Associates, Inc. for the proposed project. A copy of this evaluation is provided in Appendix IV.D-1 to the EIR. 2. ENVIRONMENTAL SETTING A. Regulatory Setting i) State of California The State of California adopted the 2007 California Building Code, Volumes 1 and 2, which is based in part on the 2006 International Building Code, on January 1, 2010. These regulations include provisions for site work, demolition, and construction, which include excavation and grading, as well as provisions for foundations, retaining walls, and expansive and compressible soils. The California Building Standards Commission is currently undergoing the 2010 annual code adoption cycle. The California Building Standards Commission will receive proposed code changes from the Department of Housing and Community Development, the Division of the State Architect – Access Compliance, the Division of the State Architect - Structural Safety, the Office of the State Fire Marshal and the Office of Statewide Health Planning and Development for code change consideration in the 2011 Annual Code Adoption Cycle. The proposed code change submittals include the text of the proposed changes and justification, and are reviewed in phases, which will conclude with the adoption of the 2011 California Building Codes on January 1, 20111 The California Seismic Safety Commission was established by the Seismic Safety Commission Act in 1975 with the intent of providing oversight, review, and recommendations to the Governor and State Legislature regarding seismic issues. The commission’s name was changed to Alfred E. Alquist Seismic Safety Commission in 2006. Since then, the Commission has adopted several documents based on recorded earthquakes, such as the 1994 Northridge earthquake, 1933 Long Beach earthquake, the 1971 Sylmar earthquake, etc. Some of these documents are listed as follows: • Research and Implementation Plan for Earthquake Risk Reduction in California 1995 to 2000, report dated December 1994; • Seismic Safety in California’s Schools, 2004, “Findings and Recommendations on Seismic Safety Policies and Requirements for Public, Private, and Charter Schools,” report dated December 1994; 1 Buildings Standards Commission, Department of General Services, website: http://www.bsc.ca.gov/prpsd_chngs/pc_09_annual_cycle.htm, February 28, 2011. Target at Sunset and Western IV.D. Geology & Soils Page IV.D-1 City of Los Angeles January 2012 • Findings and Recommendations on Hospital Seismic Safety, report dated November 2001; • Commercial Property Owner’s Guide to Earthquakes Safety, report dated October 2006; and • California Earthquake Loss Reduction Plan 2007–2011, report dated July 2007. The Alquist-Priolo Geologic Hazards Zone Act (the “Alquist-Priolo Act”) was enacted by the State of California in 1972 to address the hazards and damage caused by surface fault rupture during an earthquake. The Alquist-Priolo Act has been amended ten times and renamed the Alquist-Priolo Earthquake Fault Zoning Act, effective January 1, 1994. The Alquist-Priolo Act requires the State Geologist to establish “earthquake fault zones” along known active faults in the state. Cities and counties that include earthquake fault zones are required to regulate development projects within these zones. The Seismic Hazard Mapping Act of 1990 (the “Seismic Act”) was enacted, in part, to address seismic hazards not included in the Alquist-Priolo Act, including strong ground shaking, landslides, and liquefaction. Under the Seismic Act, the State Geologist is assigned the responsibility of identifying and mapping seismic hazards zones. The State of California Geological Survey (formerly known as the California Division of Mines and Geology), adopted seismic design provisions in Special Publication 117 Guidelines for Evaluating and Mitigating Seismic Hazards in California on March 13, 1997, and was revised as Special Publication 117A on September 11, 2008. ii) City of Los Angeles The City of Los Angeles (the “City”) adopted the 2007 California Building Code, together with the 1997 Uniform Building Code (UBC) and a series of City amendments on January 1, 2010 as the City of Los Angeles Building Code (the “Building Code”), Volumes 1 and 2. Volume 2 of the Building Code includes provisions for: 1) Foundations, Retaining Walls, and Expansive and Compressible Soils in Chapter 18; 2) Site Work, Demolition, and Construction in Chapter 33; and 3) Grading, Excavation, and Fills in a special Chapter 70 developed by and for the City. Together, the provisions in Volumes 1 and 2 of the Building Code address issues related to site grading, cut and fill slope design, soil expansion, geotechnical investigations before and during construction, slope stability, allowable bearing pressures and settlement below footings, effects of adjacent slopes on foundations, retaining walls, basement walls, shoring of adjacent properties, and potential primary and secondary seismic effects. The Building Code also addresses ground-disturbing activities, such as grading, that are codified in the Los Angeles Municipal Code (LAMC). Specifically, Chapter IX, Article 1, Section 91.7006 outlines regulations specific to the import and export of materials. Additionally, Section 91.7010 outlines regulations specific to excavations required for project construction, while Section 91.7011 outlines regulations specific to the import of fill materials to a project site. Erosion control and drainage guidelines are set forth in Section 91.7013, and regulations pertaining to flooding and mudflows are set forth in Section 91.7014. Lastly, Section 91.7016 outlines regulations specific to soil stability. The City Grading Division of the Department of Building and Safety (Building and Safety) has also adopted Rules of General Application, a series of Grading Standards that supplement the requirements of the Building Code. The Rules of General Applications include specific requirements of seismic design, slope stability, grading, foundation design, geologic investigations and reports, soil and rock testing, and Target at Sunset and Western IV.D. Geology & Soils Page IV.D-2 City of Los Angeles January 2012 groundwater. Building and Safety is responsible for implementing the provisions of the Building Code and Grading Standards. The City requires that firms performing geotechnical investigations, sampling, and testing have their laboratory certified by the Building and Safety Materials Control Section. The City’s primary seismic regulatory document is the Safety Element of the City’s General Plan, adopted November 26, 1996. The City’s regulations incorporate the State’s requirements. The objective of the Safety Element is to better protect occupants and equipment during various types and degrees of seismic events. In the City’s Safety Element, specific guidelines are included for the evaluation of liquefaction, tsunamis, seiches, non-structural elements, fault rupture zones, and engineering investigation reports. The City’s Emergency Operations Organization helps to administer certain policies and provisions of the Safety Element. The Emergency Operations Organization is a City department with representatives from all City agencies. The Administrative Code, Emergency Operation Organization Master Plan, and associated Emergency Operation Organization plans establish the chain of command, protocol, and programs for integrating all of the City’s emergency operations into one unified operation. Each City agency in turn has operational protocols, as well as plans and programs, to implement Emergency Operation Organization protocols and programs. A particular emergency or mitigation triggers a particular set of protocols that are addressed by implementing plans and programs. The City’s Emergency Operations Program encompasses all of these protocols, plans, and programs. The Safety Element goals, objectives, and policies are broadly stated to reflect the comprehensive scope of the Emergency Operation Organization. B. Existing Conditions i) Geologic Setting The project site is located in the Los Angeles Basin in the northernmost part of the Peninsular Ranges province near the boundary between the Transverse Ranges and Peninsular Ranges geomorphic provinces. The Transverse Ranges geomorphic province is characterized by east-west trending mountain ranges that include the Santa Monica Mountains. The southern boundary of the province is marked by the Santa Monica, Hollywood, Raymond, Sierra Madre, and Cucamonga faults. The Peninsular Range province is characterized by northwest/southeast trending alignments of mountains and hills and intervening basins, reflecting the influence of northwest trending major faults and folds controlling the general geologic structural fabric of the region. This province extends northwesterly from Baja California into the Los Angeles Basin and westerly into the offshore area, including Santa Catalina, Santa Barbara, San Clemente, and San Nicolas islands. This province is bounded on the east by the San Jacinto fault zone. On a smaller scale, according to the 7 ½-minute Series Topographic Quadrangle (Hollywood, California), produced by the United States Geological
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