6.6 Geology and Soils

6.6 GEOLOGY AND SOILS

6.6.1 OVERVIEW AND SUMMARY

This section analyzes potential geotechnical (e.g., soils engineering and seismic) and engineering geologic (e.g., fault and landslide) impacts resulting from project implementation. The site is currently occupied by the St. John's Seminary College, and citrus and avocado orchards.

Geotechnical and engineering geologic investigations have focused on engineering properties, geologic hazards, fault rupture and slope stability. Existing studies indicate that the development is feasible and impacts would be less than significant provided all current codes, and geotechnical report and City recommendations are followed.

6.6.2 LITERATURE AND DATA REVIEW

Reports and maps describing the geologic and soil conditions at the proposed project site include both site-specific project related studies by Geolabs-Westlake Village (Geolabs), studies by Geolabs on adjacent properties to the east, and other generally available public data sources. Other sources include published documents from federal, state, and local agencies (US Geological Survey [USGS]; California Geological Survey [CGS, formerly the California Division of Mines and Geology (CDMG)], the City of Camarillo, and Ventura County), and the Dibblee Foundation, as listed in Section 11.0, References.

Project-related Studies

The following project related reports were utilized and are also provided in Appendix 6.6:

• Geolabs-Westlake Village, June 12, 2006, “Limited Fault Location and Activity Assessment,” which describes the results of geologic exploration trenching (three fault trenches) to assess the potential for fault rupture within the development areas.

• Geolabs-Westlake Village, September 27, 2006, “Preliminary Geotechnical Considerations for Site Development” which includes the results from geotechnical and engineering geologic investigations focused primarily on geologic mapping, aerial photo review, slope stability considerations along the northern development area boundary, more on fault rupture potential, and site seismic hazard potential.

• Geolabs-Westlake Village, October 9, 2008, “Response to Review, St. John’s Seminary, City of Camarillo, California,” which responds to seven review comments by Fugro West, October 5, 2007 and describes the results of additional geologic exploration including fault trenching, drilling,

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laboratory testing, and analysis to assess the potential for fault rupture, mitigation of fault movement, landslide occurrence, slope stability, and other issues.

• Geolabs-Westlake Village, January 31, 2012, “Zones of Deformation Tract Nos. 5191, 5247, and 5248 East of St. John's Seminary, City of Camarillo, California,” which discusses zones of deformation in projects to the east and the relationship to the project area.

• Geolabs-Westlake Village, February 2, 2012, “Supplemental Discussion of the Weber fault Preliminary Geotechnical Considerations for Site Development, St. John's Seminary, City of Camarillo, California,” which describes the results of previous geologic fault exploration and provides opinions regarding the presence of potential faults capable of ground rupture within the development areas. There are numerous references to, and examples from, fault trench logs in Tract Nos. 5191, 5247, and 5248.

• Geolabs-Westlake Village, August 31, 2016, "Geotechnical Investigation, Proposed Subdivision of a portion of St. John's Seminary, Tentative Tract 5976, 5012 Seminary Road, City of Camarillo, California," which addresses the tentative grading plans by Encompass Consultant Group, and to assess the geotechnical feasibility of the project.

• Engineering Geology and Geotechnical Engineering Review, completed December 13, 2017 by FUGRO, Tract 5976 / RPD-198

• Geolabs-Westlake Village, May 1, 2017, “Update Geotechnical Investigation and Response to Engineering Geology and Soils Engineering Review, Proposed Subdivision of a Portion of St. John's Seminary, Tentative Tract 5976, 5012 Seminary Road, City of Camarillo, California.”

Geotechnical engineering properties were described in the 2006 and 2008 reports for the northern roughly one-sixth of the proposed development area where 10 borings were drilled, logged, and sampled, and for which laboratory tests were performed. It is understood that these reports were not based on specific project design alternatives, and the reports present technical conclusions and general design recommendations (e.g., fault and slope setbacks, possibly special foundations in fault deformation areas). Substantial future fieldwork, testing, and analysis is implied, suggested, and recommended.

The 2012 reports were prepared to amplify on and clarify two technical areas: (1) fault rupture potential on the so-called “Weber fault” that is mapped along the east-west canyon through the project site, and (2) zones of deformation identified in adjacent tracts to the east; Geolab’s reviewed applicable trench logs and reports to provide their opinion on these matters.

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The most recent 2016 assessments and subsequent report were to assess the geotechnical feasibility of the proposed project and not to provide final design criteria. Work for the study included excavating three additional bucket auger borings in the southeast portion of the site, collecting samples from these borings, and testing the samples. This report was reviewed by the City on December 13, 2016 for consistency with the City of Camarillo Guidelines for the Preparation of Geotechnical and Geological Studies.

Other Data Sources

Public readily available data sources include California Division of Mines and Geology (CDMG—now the California Geological Survey [CGS]) geologic mapping of active fault zones and seismic hazards, CGS probabilistic earthquake hazards assessment, USGS and Dibblee Foundation geologic mapping, the Ventura County General Plan, and the City of Camarillo General Plan Safety Element and Geotechnical Guidelines hazard zones.

6.6.3 METHODOLOGY

Project-specific technical reports and other technical data sources (maps and reports noted above in footnotes) were reviewed to establish the existing geology and soils conditions affecting the proposed project site. Consideration was given to the potential impacts due to the implementation of the proposed project considering the local and regional geology and soils setting.

6.6.4 APPLICABLE REGULATIONS

Federal Regulations

No specific federal regulations were identified that impact the geology and soils considerations. State and local regulations (e.g., building codes) reflect national and international building codes; this is discussed below.

State Regulations

Alquist-Priolo Earthquake Fault Zoning Act

The 1972 Alquist-Priolo Special Studies Zones Act 1971 resulted from the consequences of the Sylmar-San Fernando earthquake and seeks to mitigate the hazard of fault rupture by prohibiting the location of structures for human occupancy across the trace of an active fault. The Act was renamed in 1994 to the Alquist-Priolo Earthquake Fault Zoning (APEFZ) Act. The Sylmar-San Fernando earthquake produced

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surface fault rupture damage along a zone that might have been identified in advance of the earthquake had the proper studies been mandated.

The best and most feasible surface rupture mitigation is avoidance of the causative fault. Thus, the APEFZ Act mandates that cities and counties (lead agencies) require that within an Earthquake Fault Zone (EFZ) geologic investigations must be performed to demonstrate that potential development sites are not threatened by surface fault displacements from future earthquakes. To aid the various jurisdictions that function as lead agencies for project approvals in California, the California Geological Survey must delineate Earthquake Fault Zones on standard US Geological Survey topographic maps (1-inch-equals-2000-feet scale) along faults that are "sufficiently active and well defined" as defined in the Act. Quoting from the implementation guide, Special Publication 421:

Zone boundaries on early maps were positioned about 660 feet (200 meters) away from the fault traces to accommodate imprecise locations of the faults and possible existence of active branches. The policy since 1977 is to position the EFZ boundary about 500 feet (150 meters) away from major active faults and about 200 to 300 feet (60 to 90 meters) away from well-defined, minor faults. Exceptions to this policy exist where faults are locally complex or where faults are not vertical.

Lead agencies have the responsibility to regulate most development projects within the Earthquake Fault Zones as described in the APEFZ Act, but may enact more stringent regulations. Certain smaller residential developments can be exempt. Camarillo currently has several APEFZs, with the Simi-Santa Rosa fault creating an east-west trending zone across the far eastern portion of the proposed site.

There are ten fault lines identified in the Camarillo General Plan Safety Element. These faults are considered the most significant active fault zones that are capable of seismic ground shaking and can impact the City. These include: the Simi-Santa Rosa Fault, Anacapa-Dume Fault, Bailey Fault, Wright Road Fault, Sycamore Canyon and Boney Mountain Faults, Oak Ridge Fault System, Ventura-Pitas Point and Country Club Faults, Red Mountain/San Cayetano/Santa Susana/ San Fernando Fault System, Santa Ynez Fault, North County Line Faults, and the San Andreas Fault.2

1 Details regarding the 2007 Interim Revision of the Alquist-Priolo Earthquake Fault Zone Act can be found at http://www.consrv.ca.gov/CGS/rghm/ap/index.htm. 2 City of Camarillo, General Plan: Safety Element, 2013.

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Seismic Hazards Mapping Act

The 1990 Seismic Hazards Mapping Act (SHMA)3 addresses the primary earthquake hazard, strong ground shaking, as well as the secondary hazards of liquefaction, earthquake-induced landslides, and in some areas zones of amplified shaking. As with the APEFZ Act, the California Geological Survey is the primary state agency charged with implementing the SHMA, and CGS provides local jurisdictions with the 1-inch-equals-2000-feet scale seismic hazard zone maps that identify areas susceptible to liquefaction, earthquake-induced landslides, and amplified shaking. Site-specific hazard investigations are required by the SHMA when a development project is located within one of the Seismic Hazard Mapping Zones (SHMZ) defined as a zone of required investigation.

Lead agencies with the authority to approve projects shall ensure that

The geotechnical report shall be prepared by a registered civil engineer or certified engineering geologist, having competence in the field of seismic hazard evaluation and mitigation. The geotechnical report shall contain site-specific evaluations of the seismic hazard affecting the project, and shall identify portions of the project site containing seismic hazards. The report shall also identify any known off-site seismic hazards that could adversely affect the site in the event of an earthquake. and

Prior to approving the project, the lead agency shall independently review the geotechnical report to determine the adequacy of the hazard evaluation and proposed mitigation measures and to determine the requirements of Section 3724(a), above, are satisfied. Such reviews shall be conducted by a certified engineering geologist or registered civil engineer, having competence in the field of seismic hazard evaluation and mitigation.

CGS Special Publication (SP) 1174 and companion volumes for implementation of the SP 117 process (one volume for liquefaction and one volume for earthquake-induced landslides)5 provide detailed guidance for lead agencies to review SHMA reports. The overall goal is to protect the public by minimizing property damage and the loss of life.

The City of Camarillo has been mapped pursuant to the SHMA and there are zones of required investigation for liquefaction and earthquake-induced landslide hazards within and adjacent to the

3 Details regarding the Seismic Hazards Mapping Act can be found at http://gmw.consrv.ca.gov/ shmp/SHMPpgminfo.htm. 4 California Geological Survey, Special Publication (SP) 117: Guidelines for Evaluating and Mitigating Seismic Hazards in California; http://gmw.consrv.ca.gov/shmp/webdocs/sp117.pdf. 5 Recommended Procedures for Implementation of SP117; http://www.scec.org/resources/catalog /LiquefactionproceduresJun99.pdf and http://www.scec.org/resources/catalog/LandslideProceduresJune02.pdf.

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proposed site (Camarillo and Newbury Park Quadrangles). In addition, the City of Camarillo adopted the Guidelines for the Preparation of Geotechnical and Geological Studies in 2008. It contains specific requirements for materials to be provided by geotechnical reports prepared for the City, and includes fault and liquefaction maps within City boundaries.

Natural Hazards Disclosure Act

The Natural Hazards Disclosure Act (effective June 1, 1998), requires:

that sellers of real property and their agents provide prospective buyers with a "Natural Hazard Disclosure Statement" when the property being sold lies within one or more state-mapped hazard areas, including a Seismic Hazard Zone.

The SHMA specifies two ways in which this disclosure can be made:6

c. In all transactions that are subject to Section 1103 of the Civil Code, the disclosure required by subdivision (a) of this section shall be provided by either of the following means:

1. The Local Option Real Estate Transfer Disclosure Statement as provided in Section 1102.6a of the Civil Code, or

2. The Natural Hazard Disclosure Statement as provided in Section 1103.2 of the Civil Code.

The Local Option Real Estate Disclosure Statement can be substituted for the Natural Hazards Disclosure Statement can be made if it contains substantially the same information and substantially the same warning as the Natural Hazards Disclosure Statement. Both the APEFZ Act and the SHMA require that real estate agents, or sellers of real estate acting without an agent, disclose to prospective buyers that the property is located in an APEFZ or SHMZ.

Building Codes

Building regulations are specified in of the Camarillo Municipal Code,7 including adoption of the 2013 California Building Code (CBC) (the CBC is based on the 2012 International Building Code [IBC]). Standard residential, commercial, and light industrial construction is governed by the CBC, which the City has amended and provided additions to. Due to the type, quality, and age of some of the City

6 Public Resources Code-Section 2690-2699.6: Seismic Hazards Mapping Act http://gmw.consrv.ca.gov/shmp /prc_shmact.htm. 7 City of Camarillo, Municipal Code, Title 16, Chapter 16.04, Sections 16.04.010 and 16.04.025.

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buildings, the 2013 State Historical Building Code8 (SHBC) applies to the strengthening of unreinforced historic structures, while the 1986 Unreinforced Masonry Law9 applies to the identification, reporting, and retrofit of non-historic Unreinforced Masonry (URM) buildings. The 2013 CBC10 includes additions to the previous building code that make it more stringent, in particular with regard to seismic and earthquake conditions for critical structures such as essential facilities, public schools and hospitals. The CBC, which is included in Title 24 of the California Code of Regulations, is a compilation of three types of building standards from three different origins:

• Those adopted by state agencies without change from building standards contained in national model codes (e.g., the IBC)

• Those adopted and adapted from the national model code standards to meet California conditions (e.g., most of California is Seismic Design Categories D and E)

• Those authorized by the California Legislature, which constitute extensive additions not covered by the model codes that have been adopted to address particular California concerns (e.g., the specification of Certified Engineering Geologist rather than engineering geologist)

International and national model code standards adopted into Title 24 apply to all occupancies in California except for modifications adopted by state agencies and local governing bodies. Facilities and structures such as power plants, freeways, emergency management centers (traffic, 911), and dams are regulated under criteria developed by various California and federal agencies.

Local Regulations

City of Camarillo

The City of Camarillo Department of Community Development, which oversees the Building and Safety Department has the responsibility for land development review and engineering approvals of all private development within the City to ensure compliance with City codes, ordinances and policies, and is responsible for the preparation of conditions of approval for development projects. The City has adopted the 2016 CBC.

The revised Safety Element of the City of Camarillo General Plan was adopted in 2013 and includes mapping of known seismic and other geologic hazards within the City. It contains geology and soils

8 The State Historical Building Code is defined in Part 8 of Title 24, http://ohp.parks.ca.gov/pages/1074/files/2013%20CHBC.pdf 9 Section 8875 et seq, of California’s Government Code 10 The California Building Code is defined in Part 2 of Title 24, http://www.bsc.ca.gov/apprvd_chngs/appStan.htm.

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related “recommendations” that serve as the policies referred to in this document. These policies and an analysis of the project’s consistency with these policies are provided in a later section.

The City of Camarillo adopted the Guidelines for the Preparation of Geotechnical and Geological Studies in 2008. It contains specific requirements for materials to be provided by geotechnical reports prepared for the City, and includes fault and liquefaction maps within City boundaries.

6.6.5 EXISTING CONDITIONS

The proposed 88.45 acre project site is currently occupied by the St. John's Seminary College, and citrus and avocado orchards. The St. John’s Major Seminary is located west of the site, with residential development located to the east, southeast, and south of the site. Calleguas Creek runs along the northern and western borders of the St. John’s Seminary property.

Topography of the proposed residential development area generally slopes from northeast to southwest, but is divided into two individual ridge areas separated by a blue-line (channelized) stream drainage.11

In order to characterize the geologic conditions on the project site, existing regional mapping was examined; geologic mapping was conducted by Geolabs; limited geotechnical exploration was conducted in the northern portion of the proposed residential development area; and fault exploration was conducted in the central and southern portions of the proposed residential development area. Previous studies for neighboring residential development were reviewed by the project geotechnical engineer-of- record Geolabs.

The proposed residential development area (88.45 acres) is underlain by Saugus Formation bedrock, alluvium/colluvium, and artificial fill. Saugus Formation has moderately hard to hard claystone, siltstone, sandstone, and conglomerate units that have contributed to the composition of the younger surficial deposits. In general, the surficial deposits are loose to medium dense sand, silt, and clay mixtures. Groundwater was not encountered in the exploratory borings along the north edge of the proposed residential development area.

11 Geolabs, 2006b, Preliminary Geotechnical Considerations for Site Development, St. John’s Seminary, City of Camarillo, California, September 27, 2006.

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Regional Geologic and Seismic Setting

Physiography, Topography, and Geologic and Soil Units

The project site is within the Transverse Range Geomorphic Province, a mountainous region consisting of contiguous, east-west trending mountain ranges and valleys. The Transverse Ranges are an anomalous east-west trending geological province of deformation associated with relative movement of the North American and Pacific Plates. The project site is located in the northeastern portion of the City of Camarillo at the western end of the Las Posas Hills along the northern edge of the Santa Monica Mountains. The Las Posas Hills are bordered on the north by Las Posas Valley and on the south by Santa Rosa and Pleasant Valleys. Elevations in the vicinity of the project site range from approximately 200 to 400 feet above mean sea level (amsl).

Faulting, Seismicity and Strong Ground Shaking

Faulting

This portion of the Transverse Ranges is underlain by Tertiary and Quaternary sedimentary and volcanic rocks, and is characterized by east-west trending folds and steeply dipping compressional faults. Young geologic structures dominate the area as a result of the region’s active seismicity. The geology of the local area is shown in Figure 6.6-1, Regional Geology Map. Major surface faults and fault zones associated with the Transverse Ranges generally parallel the province, and include the Simi-Santa Rosa, Northridge, Malibu Coast, Anacapa-Dume, Oak Ridge, Santa Monica, and numerous offshore faults (Figure 6.6-2; Regional Fault Map).

Some earthquake faults are not exposed at the surface; these faults are buried (blind) thrusts. Faults such as these were responsible for the 1987 Whittier and 1994 Northridge earthquakes. The classification process for these faults is incomplete, and questions remain about the extent of earthquake activity for various discovered blind thrust faults. Three such buried thrust faults that could affect the site are the Santa Monica Mountains, Northridge, and Puente Hills faults. All of Southern California is characterized by active and potentially active faults that present potential risks to structures (most commonly strong ground shaking, fault rupture within a fault zone, liquefaction and settlement, landslides/slope instability, and flooding); these are discussed in the subsections below.

Seismicity and Strong Ground Shaking

The principal factors determining the level of seismic ground shaking risk at a location are (1) the distance to the active and potentially active faults capable of causing a moderate to large earthquake; (2)

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the maximum and probable earthquake magnitudes for each fault; (3) the recurrence interval (average time between each) earthquake (slip rate); and (4) the type of geologic or man-made materials (e.g., artificial fill, alluvium, or bedrock) underlying the location.

Ground shaking is the primary hazard most likely to affect the project area, based primarily upon its proximity to active or potentially active faults. Active or potentially active faults near the project site are listed in Table 6.6-1, Earthquake Ground Shaking Parameters for Potential Earthquake Faults near the City of Camarillo. The top nine selected faults are estimated to be capable of generating a peak ground acceleration of greater than 0.10 g (standard gravity) and a Modified Mercalli Intensity of at least VIII; the San Andreas Fault was added due to its regional importance.

Other inactive or poorly studied faults (some apparent groundwater barriers) may be present within 15 miles of the proposed site; however the faults listed in Table 6.6-1 are considered representative of earthquake ground shaking conditions potentially impacting the proposed site.

Table 6.6-1 Earthquake Ground Shaking Parameters for Potential Earthquake Faults near the City of Camarillo1 Assumed Assumed Assumed Assumed Distance Maximum Minimum Maximum Minimum Miles Magnitude Magnitude Magnitude Magnitude Fault Name (Kilometers) (Ellsworth) (Ellsworth (Hanks) (Hanks) Simi-Santa Rosa 0.7 (1.1) 6.9 6.5 6.7 6.5 Bailey2 1.8 (3.0) unknown unknown unknown unknown Oakridge (Onshore) 3.7 (5.9) 7.2 6.5 7.1 6.5 Wright Road Fault 5.6 (9) Unknown Unknown Unknown unknown Sycamore Canyon Fault 9.9 (16) Unknown Unknown Unknown Unknown Anacapa-Dume Fault 6.7 (10.8) 7.0 6.5 6.8 6.5 Ventura-Pitas Point Fault 10.6 (17.1) 6.8 0.16 VIII Red Mountain/San 12.6 (20.3) 7.4 6.5 7.4 6.5 Cayetano Fault Santa Ynez Fault 21 (33.8) 7.4 6.5 7.3 6.5 North County Fault 24 (38.6) 6.8 6.5 6.8 6.5 San Andrea Fault 39.3 (63.3) 7.8 6.5 7.9 6.5

Notes: 1 Source: https://earthquake.usgs.gov/cfusion/hazfaults_2008_search/query_main.cfm 2 The precise fault location is uncertain; the fault is presumed to be approximately 12 miles long. The maximum potential earthquake magnitude and the slip rate are unknown. The fault is thought to have last ruptured during the late Quaternary (i.e. during the last approximately 700,000 years). Geologic and Geotechnical Study, Santa Paula West Industrial Park Specific Plan, Adjacent to the Southwest Portion of the City of Santa Paula, Unincorporated Ventura County, California, Leighton Consulting, Inc., June 2015.

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Legend: Qa alluvium: gravel, sand and clay of flatlands Qoa dissected, weakly indurated alluvial gravel, sand and clay QTs weakly indurated, light gray to light brown pebble-cobble gravel, sand and clay; includes indurated paleo-soil layers locally; gravel contains clasts of granitic and metavolcanic rocks, quartzite and siliceous shale (Monterey Formation) Tcvbb basaltic flow breccias: dark gray to reddish brown, porphyritic, dense to scoriaceous basalt; contains small phenocrysts of plagioclase feldspar and hypersthene (Williams, 1983); moderately coherent, erosion-resistant

2000 1000 0 2000

n APPROXIMATE SCALE IN FEET SOURCE: Dibblee, T.W., Jr., and Ehrenspeck, H.E., 1990, Geologic Map of the Camarillo and Newbury Park Quadrangles, Ventura County, California: Dibblee Foundation Map DF-28

FIGURE 6.6-1 Regional Geology Map

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Oakridge (Onshore) Fault Zone

Ventura Fault Zone Simi-Santa Rosa Fault Zone

Project Site

Legend: Project Site Positively Identified 4 2 0 4 See Table 6.6-1 for selected faults and fault parameters; Los Angeles County and offshore faults not shown. n APPROXIMATE SCALE IN MILES SOURCE: Ventura County General Plan Hazards Appendix - November 2005; Dibble Fault Maps - January 2002

FIGURE 6.6-2A Regional Fault Map

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Source: City of Camarillo GIS Data dated October 31, 2001; ESRI Terrain Basemap. SOURCE: City of Camarillo GIS Data, October 31, 2001; ESRI Terrain Basemap CAMARILLO SAFETY ELEMENT FIGURECamarillo 6.6-2B Fault Map 05/13 • JN 10-108718 (130358) Camarillo Fault Map Exhibit 11-2

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6.6.5.2 Local Setting

Geology and Soils

Local geologic units consist of surficial deposits (various ages of alluvium/stream channel deposits) and bedrock formations. The Dibblee and Ehrenspeck map (Figure 6.6-1) was selected to show the local geology because their geologic units are consistent across the Camarillo-Newbury Park quadrangle boundaries. Considering their compilation, surficial deposits associated with the project site consist of Quaternary stream channel sand and gravel (Qg) and general Quaternary alluvium (sand, gravel, and clay in the flatlands; Qa). Older alluvium (Qoa) is also present south of the project area. Alluvium occupies the drainage trending northeast-southwest through the project area. Bedrock in the northeast corner of the Camarillo Quadrangle consists of Tertiary to Pleistocene-age formations including from youngest to oldest: Saugus Formation (QTs), Las Posas Sand (Qtlp), Conejo Volcanics (Tcv), and Lower Topanga Formation (detrital sediments of Lindero Canyon [Tlp]). Saugus Formation is exposed in the high relief areas of the project site.

Fault Rupture

The Simi-Santa Rosa fault zone passes near (immediately south and east) and based on some geologic studies may pass through, the proposed project site. Fault surface-rupture represents a primary or direct potential hazard to structures built within an active fault zone. This results from ground displacement (the ground on each side of a fault moves in opposite directions vertically and/or laterally) and differential uplift (arching) of the ground surface causing tilting and severe cracking at the surface above the fault. Various other studies12 have mapped, or compiled, fault locations in the vicinity of the project site, although there are differences in the locations of faults within and near the site.

A paleoseismic evaluation of the Simi-Santa Rosa fault zone at Arroyo Simi approximately 10 to 12 miles east of the proposed site provides an idea of possible fault zone characteristics near the proposed site. The Simi-Santa Rosa fault is estimated to be approximately 17.5 miles long, extending from the northeastern Simi Valley (east of the proposed site) to the west end of the Camarillo Hills (west of the proposed site). It

12 Dibblee, T.W., Jr., and Ehrenspeck, H.E., 1990, Geologic Map of the Camarillo and Newbury Park Quadrangles, Ventura County, California: Dibblee Foundation Map DF-28, scale 1:24000. Weber, F.H., Jr., Cleveland, J.E., Kahle, J.E., Kiessling, E.W., Miller, R.V., Mills, M.F. and Morton, D.M., 1973, Geology and mineral resources study of southern Ventura County, California: California Division of Mines and Geology Preliminary Report 14, 102 p., map scale 1:48,000. Siang, S. T., K. B. Clahan, and C. S. Hitchcock, 2004, Geologic Map of the Camarillo 7.5' Quadrangle, Ventura County, California: a Digital Database Version 1.0. Yerkes, R. F., and R. H. Campbell, 2005, Preliminary Geologic Map of the 30' x 60' Los Angeles Quadrangle, Southern California, USGS OFR-2005-1019.

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is a reverse-left oblique fault (the north side moving up and to the west) with a slip rate estimated at 1.0 millimeter per year (mm/yr) ± 0.5 mm/yr. The paleoseismic study identified two Holocene earthquakes on the fault (roughly 1,100 to 1,500 years before present [ybp] and 4,500 to 7,200 ybp) and a cumulative vertical displacement/deformation of 3.2 meters (over 9 feet, averaging 1.6 meters per event). A similar average displacement (0.6 to 1.1 meter) occurred on the Springville fault within the Simi-Santa Rosa fault zone to the west of the project site during the 1,000- to 2,000-ybp timeframe. The low-to- moderate angle thrust fault style produces are variation in fault types, such a forethrusts, backthrusts, uplift, tilting, and collapsed fault scarps.13

The Simi-Santa Rosa fault zone projects into and toward the proposed residential development area from an APEFZ (Figure 6.6-3, APEFZ14 and Camarillo Fault Hazard Map15) designated within the adjacent Newbury quadrangle on the east by Treiman.16 The Treiman FER-244 report and map (2A) summarize the engineering geology fault investigations performed in the Newbury quadrangle to the east of the proposed site and within the site area. Treiman bases the boundaries of the APEFZ on the two active faults (Simi fault and Simi fault splay) shown on the APEFZ map that have specific fault trenching investigation results. He shows the Weber fault trace, but no reports of fault investigation trenches across the fault near the proposed site had been published at that time his report was being compiled. FER-48 (Camarillo quadrangle) reported on the west portion of the project site and shows the Weber fault as being located within the east-west canyon.

13 Treiman, J. A., 2010, Fault Rupture and Surface Deformation: Defining the Hazard, Environmental & Engineering Geoscience, Vol. XVI, No. 1, February 2010, pp. 19–30 19. 14 CDMG, 1998, State of California Earthquake Fault Zones, Camarillo quadrangle, May 1, 1998, scale 1:24,000; CDMG, 1999, State of California Earthquake Fault Zones, Newbury Park quadrangle, May 1, 1999, scale 1:24,000. 15 City of Camarillo, 2003, Camarillo Geotechnical Guidelines, Plate 6.B, Fault-Rupture Hazard Map (NE). 16 CDMG. Treiman, J.A., Simi-Santa Rosa Fault Zone in the Moorpark, Newbury Park, Simi Valley East, Simi Valley West, and Thousand Oaks quadrangles, Ventura County, California: CDMG FER-244, 21 pp. 1998.

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Camarillo Fault Rupture Hazard Zone Alquist-Priolo Earthquake Fault Zone 2K 1K 0 2K

n APPROXIMATE SCALE IN FEET INSET NOT TO SCALE SOURCE: City of Camarillo, City of Camarillo Geotechnical Guidelines Plate 6B, Fault Rupture Hazard Map (NE) – 2003

FIGURE 6.6-3 APEFZ and Camarillo Fault Hazard Zone Map

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Dibblee and Ehrenspeck show a fault (so-called Dibblee fault) south of, and parallel to, the Weber fault within the project site Saugus bedrock. This appears to correspond to the Simi fault shown by Treiman. Parallel and further south is the axis of an anticline (arch or up-fold) lying between the Simi fault and the Simi fault splay. Off site to the south Dibblee shows the Santa Rosa fault, as does Treiman.

There are several fault lines that have been mapped traversing the project site. Site-specific fault studies evaluating those faults are discussed in the Project Site Geology: Fault Rupture section below. The Simi- Santa Rosa fault has been mapped to the south. Due to the proximity of the project site to multiple fault lines, the proposed project would be subject to strong ground shaking.

Liquefaction and Earthquake Induced Settlement

Soil liquefaction occurs when saturated granular (not clay-rich), low to medium relative density soils are subjected to sufficiently strong long duration earthquake vibrations. The vibration causes an increase in soil pore pressure as the water in pores resists the tendency for the soil to reduce its volume. When the pore water pressure reaches the vertical effective stress (roughly equal to the weight of the overburden), the soil particles become suspended in water causing a complete loss in soil strength as it behaves more like a viscous liquid. Liquefaction can cause excessive structural settlement, ground rupture, lateral spreading (landslide-like movement), or failure of shallow bearing foundations. Significant liquefaction related effects are typically limited to the upper 50 feet of the subsurface soils. Figure 6.6-4, Historically High Groundwater, Potential Liquefaction and Earthquake-Induced Landslides, shows no indication of liquefaction potential within the proposed project areas.

Loose unsaturated sandy soils that are subjected to moderate to strong ground shaking can experience settlement due to densification and volume reduction. Experience from the Northridge Earthquake indicates that structural distress can result from such seismic settlement unless soils have adequate density to resist seismically induced settlement. Differential settlement is often observed at the contact between two materials of very dissimilar density, such as alluvium or artificial fill against Saugus Formation bedrock.

Geolab's Geotechnical investigation of the project site noted that artificial fill, colluvium, stream channel deposits, alluvium, landslide deposits, and Saugus formation were located on the project site. Saugus formation consists of consolidated but usually uncemented claystones, siltstones, sandstones, and fine conglomerates, locally bedded but usually massive gradationally bedded. This bedrock formation underlies all other geologic material across the site.

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Landslides

Seismically induced landslides and other types of slope failures, such as lateral spreading, can result in the event of an earthquake. This may be the case where there are steep slopes, weak bedrock or surficial materials, or shallow groundwater. Figure 6.6-4 indicates a potential for earthquake-induced landslide activity along the northern edge of the proposed residential development area adjacent to Calleguas Creek and along the south edge of the alluvial filled drainage in the south central portion of the proposed residential development area.

In response to 2007 City review comments on the Geolabs 2006 geotechnical report, Geolabs conducted additional field investigation, laboratory testing, and slope stability analysis for this area above and adjacent to Calleguas Creek. In their 2008 report Geolabs concluded that the static slope stability for this northern area has a factor of safety greater 1.5 considering 2007 CBC requirements, and that distributed seismically induced slope deformation in the range of 5 to 15 centimeters could occur within the slope mass. This deformation was not considered to be along planes of weakness, but is distributed throughout the mass. Analysis was done for the alluvial filled drainage area slopes within the planned development area in 2016. Recommendations from this report include the removal of colluvium (Qc), portions of the alluvium (Qal), landslide debris (Qls) existing fill materials, and weathered bedrock in the development area should be removed to firm bedrock or competent alluvium and replaced with properly compacted engineered fill. There are six lots in the vicinity of borings B18 and B19 that extend into the area of alluvium. The area of these lots should have the alluvium removed to bedrock.

Earthquake-Induced Dam Failure Flooding, Seiche, and Tsunami

Earthquake-induced flooding is caused by failure of up gradient dams or other water-retaining structures during an earthquake. Review of the Ventura County General Plan17 indicates that no areas within the proposed residential development area would be subject to such flooding (Figure 6.6-5, Dam Failure Inundation Flooding Potential). Severe erosion would be likely along the north edge of the development as water flowed to the west.

Tsunami and seiches are large seismically generated waves in the ocean or other large enclosed bodies of water, respectively. Based upon the site elevation and distance to the ocean, lakes, and/or reservoirs, there is no potential for tsunami or open water seiches to affect the project site. There is a water tank immediately northeast of the proposed residential development area at an elevation above 360 feet amsl.

17 Ventura County, 2005, General Plan Hazards Appendix, Last Amended by the Ventura County Board of Supervisors on October 22, 2013; Figure 2.11.2, Dam Inundation Areas, South Half.

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A failure of this tank due to earthquake ground shaking, ground failure, or seiching (sloshing) of water could release water onto the site.

Non-Earthquake Geologic and Soils Hazards

Subsidence

Generalized ground subsidence can affect broad areas where either groundwater withdrawal or oil extraction is occurring within underlying geologic formations. This is due to the reduction in pore space within the formations due to removal of fluids and formation compression from the weight of overlying geologic materials. The Ventura County subsidence area map18 indicates that the site is not within an area of known subsidence.

18 Ibid; Figure 2.8 Probable Subsidence Zone.

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Legend: Potential Liquefaction Earthquake-Induced Landslides Groundwater Barrier 80’ Water Depth Contour Valley/Mountain Boundary Water Well 1000 500 0 1000

n APPROXIMATE SCALE IN FEET SOURCE: CDMG, 1998, State of California Seismic Hazard Zones, Camarillo quadrangle - February 7, 2002

FIGURE 6.6-4 Historically High Groundwater, Potential Liquefaction and Earthquake-Induced Landslides

0037.030•12/16 Project Site

Source: City of Camarillo GIS Data dated August 28, 2012; ESRI Terrain Basemap. SOURCE: City of Camarillo Safety Element, 2013; ImpactSciences, Inc., 2016 CAMARILLO SAFETY ELEMENT FIGUREDam 6.6-5 Inundation Areas 05/13 • JN 10-108718 (130358) Dam Inundation Areas Exhibit 11-6

037-030•12/ 16 6.6 Geology and Soils

Landslides

Landslides result from the lateral displacement, or fall, of a dislodged rock or soil mass that moves down or along a sloped surface. This can include large bedrock block glide or rotational failures, rockfalls in very steep terrain, slumps and rotational failures in massive alluvial formations, and debris flows and mudslides composed of saturated rock and soil material. The City of Camarillo General Plan19 indicates that the proposed residential development area is within a “high” potential landslide/mudslide zone. The Ventura County General Plan20 does not show a landslide within the proposed site, but does show a few large landslides along the north slopes abutting Calleguas Creek east of the proposed site. As discussed above, in their 2008 report Geolabs concluded that the static slope stability for this northern area has a factor of safety greater 1.5 considering 2007 CBC requirements.

Shallow Groundwater

Shallow groundwater can be a nuisance and a safety hazard if it occurs within the depth of grading where special equipment and dewatering may be necessary. Shallow water can also lead to liquefaction, lateral spreading, and slope instability if the geologic formation type and earthquake ground shaking conditions are conducive. Historically, the highest groundwater levels (see Figure 6.6-4) do not project groundwater into the alluvial deposits that fill the central drainage within the project. Groundwater has not been encountered in any of the site's exploratory excavations outside the alluvial deposits in the central canyon. In that canyon, small amounts of water were found in several borings, apparently perched on the bedrock that underlies the alluvium or within the bedrock. It occurs at depths of about 25 feet below the surface. Most of the proposed residential development area is in Saugus Formation bedrock.

Weak, Consolidation-Prone, Erodible, and Expansive Soils

Surficial geologic and man-made deposits would be affected by the proposed mass grading necessary for development in the proposed residential area. Five geologic units are within the proposed residential development area. These units are discussed briefly in the Project Site section below.

19 City of Camarillo, 2013, General Plan Safety Element, Hazards Plate 1-Fault Hazards Zone (Liquefaction Susceptibility Map Exhibit 11-4. 20 Ventura County, 2005, General Plan Hazards Appendix, Last Amended by the Ventura County Board of Supervisors on October 22, 2013; Figure 2.7.1b Mapped Landslides.

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Project Site Geology

Project site geology and soil conditions are discussed below. Technical issues discussed in the local area discussion that do not affect the proposed project site are not discussed within the Project Site section; these are subsidence and tsunami. Also, the individual technical issue discussions are combined into fewer subsections: (1) Landslides (earthquake-induced landslides and landslides), (2) Liquefaction and Shallow Groundwater, (3) Flooding (flooding, earthquake dam failure-induced flooding, and seiche), and Soils Engineering Considerations (weak, consolidation/settlement-prone, erodible, and expansive soils).

Geology and Soils Units

Based on Geolabs' studies21 (see Figure 6.6-6, Project Site Geology Map), the following paragraphs describe the character and distribution of the five geologic and soil units encountered during their subsurface investigation within the proposed residential development area.

These five units are: (1) Man-made undocumented fill (map unit Af) related to previous development of the Seminary and surrounding orchards, (2) Quaternary colluvium on the hillsides (map unit Qc), (3) Quaternary alluvial deposits in the main surface drainage and along Calleguas Creek (Qal), (4) Plio- Pleistocene Saugus Formation bedrock (Qs), and (5) landslide deposits (Qls) derived from the bedrock and shallow colluvial deposits.

Geolabs22 provides brief descriptions of the artificial fill (Af) in its trench (FT-2) and boring (B-4) logs. It consists of dark yellowish to dark grayish brown, loose (soft) to dense (stiff) clayey sand and sandy clay with scattered gravel, some carbonate “infilling,” and roots up to 0.5 inch in diameter. Fill thickness is unknown but could be several tens of feet thick in filled drainage areas (e.g., 14 to 18 feet thick in FT-2).

Younger and older colluvium (Qc), and young and older alluvium (Qal), deposits are likely Holocene to Pleistocene age at the oldest and were mapped where thicknesses exceed approximately 5 feet. Generally they are composed of very dark brown to dark gray brown, loose, moist clayey to silty sand with occasional gravelly sequences, scattered gravel, caliche stringers, and roots up to 2 inches in diameter. Based on the fault exploration trench logs these deposits vary from a few feet thick to over 20 feet thick (FT-3B) outside the main drainage. Within the main drainage the colluvium/alluvium sequence was not fully penetrated, but would be expected to exceed 20 feet.

21 Geolabs. Preliminary Geotechnical Considerations for Site Development, St. John’s Seminary, City of Camarillo, California, September 27, 2006. 22 Ibid.

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Qsc

Legend: Lithological Units Approximate location of fault trench by GWV for Artificial Fill Tract 5248 Stream Channel Deposits Approximate location of fault trench by GWV Alluvium 2005-2006 Colluvium Approximate Limits of Landslide Deposit Landslide Deposits Saugus Formation Strike and dip of (includes San Pedro Formation) approximate bedding Geologic Contact, dashed where approx., dotted where concealed Strike and dip of bedding

Cross Section Strike and dip of fault 24 in. dia. boring by Geolabs- or shear 800 400 0 800 Westlake Village (GWV) 2005 Borings by Geolabs-Westlake Village Strike and dip of joint (GWV) during Tract 5248 investigation or fracture n APPROXIMATE SCALE IN FEET Boring by Fugro West, Inc. SOURCE: Preliminary Geotechnical Report Considerations for Site Development, Geolabs-Westlake Village, p.16 - 2006

FIGURE 6.6-6 Project Site Geology Map

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The Pleistocene-age Saugus Formation (Qs—the equivalent of Dibblee and Ehrenspeck QTs) consists of claystone, siltstone, and poorly sorted clayey to silty sandstone, pebbly sandstone, and sandy conglomerate. The conglomerate clasts are generally rounded and primarily derived from granitic and metamorphic source areas, although lenses of angular shale clasts were derived from the Monterey/Modelo Formation bedrock. The Saugus Formation was deposited in a fluvial/floodplain environment (e.g., over-bank deposits on fans or deltas), exhibiting nested channels, cross-bedded sequences, and scour-and-fill features.

Two small landslides (less than 120 feet in maximum dimension) are mapped by Geolabs23 on the project site, and a few others of similar size immediately north and northeast of the site. The two small landslides are discussed in more detail below.

Fault Rupture

As noted above, a splay of the Simi-Santa Rosa fault zone has been mapped along the northeast- southwest trending drainage through the proposed project site, as shown on the City of Camarillo Fault- Rupture Hazard Map (Figure 6.6-3). Project site investigations by Geolabs cited in Section 6.6.2.1 conclude that there is no Holocene faulting within the proposed residential development area (see Figure 6.6-7, Fault Trench Location Map). The apparent similarity in Simi-Santa Rosa fault history east and west of the site, and the finding of no Holocene faulting by Geolabs suggests several options, either (1) the surface rupture was discontinuous along the fault zone and did not affect the site, (2) that the surface rupture was along the trace of the “Santa Rosa fault” over 750 feet to the south and east of the proposed project, (3) that the fault passed beneath some Geolabs trenches on the project site and the trenches in the properties to the east, or (4) conclusions reached by Geolabs based on Fault Trench 9 (FT-9) exposures may be subject to an alternative interpretation. The fault trace through the property as mapped by Weber and others24 (apparently the earliest comprehensive compilation of mapping for the area) is in the alluvial-filled canyon not completely crossed by the Geolabs trenches FT-1 and FT-2 (northern ends) and FT-3B (southern end). Also, the northern 150 feet of FT-1, the northern 50 feet of FT-2, and the southern 20 feet of FT-3B are within young alluvium or landslide materials, therefore may not show evidence of the fault. The study did not provide “a continuous exposure completely across the westerly terminus of the APEFZ” and leaves the young alluvium (map symbol Qal on Figure 6.6-6) within the northeast- southwest trending drainage unexplored. Conclusions regarding offsets mapped in FT-9 are discussed further below.

23 Geolabs-Westlake Village, “Preliminary Geotechnical Considerations for Site Development,” 2006. 24 Weber, F.H., Jr., Cleveland, J.E., Kahle, J.E., Kiessling, E.W., Miller, R.V., Mills, M.F. and Morton, D.M., 1973, Geology and mineral resources study of southern Ventura County, California: California Division of Mines and Geology Preliminary Report 14, 102 p., map scale 1:48,000.

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Within trench FT-1 between roughly stations 4+15 and 4+25, Geolabs25 mapped one “separate and distinct minor fault” with an attitude (strike and dip) of north 74 degrees west (strike) and a dip of 26 degrees to the northeast. The orientation is sub-parallel to the mapped fault splay through the drainage and the low dip-angle suggested that the fault trace would be sinuous across areas of topographic relief. Geolabs indicated that this is a low-angle reverse fault (26-degree northerly dip) had up to about 6 inches of displacement contained within the bedrock and did not appear to offset or deform the contact between the Saugus Formation bedrock and overlying colluvium. No other faults were discovered in FT- 1 or the other fault trenches in the 2006 study.

The fault encountered in trench FT-1 is outside the APEFZ (online with the APEFZ and less than 200 feet to the west) and inside the City of Camarillo Fault-Rupture Hazard Zone,26 a zone that may contain active or potentially active faults. CDMG27 projected two faults toward the site from the east. These faults were selected based on trenching results (evidence of active faults in one or more trenches) and based on uncertainties in trenching results (inconclusive evidence)28. Geolabs29 showed on their Plate 1 a series of four trenches (T-2, 2A, 2B, and 2C) immediately east of the proposed project site along strike from the FT-1 fault that may indicate a similar fault was being traced within Tract No. 5248, although no details of these studies are provided at that time. Geolabs recommended similar future trenching to locate the FT-1 fault surface trace in more detail and to establish a potential zone of deformation around the FT-1 fault.

25 Geolabs. Limited Fault Location and Activity Assessment, Proposed Subdivision, Portion of St. John’s Seminary Property, Upland Road, City of Camarillo, California, June 12, 2006. 26 City of Camarillo, 2003, Camarillo Geotechnical Guidelines, Plate 6.B, Fault-Rupture Hazard Map (NE). 27 CDMG. State of California Earthquake Fault Zones, Newbury Park quadrangle, May 1, 1999, scale 1:24,000. 1999. 28 CDMG. Treiman, J.A., Simi-Santa Rosa Fault Zone in the Moorpark, Newbury Park, Simi Valley East, Simi Valley West, and Thousand Oaks quadrangles, Ventura County, California: CDMG FER-244, 21 pp. 1998. 29 Geolabs. Preliminary Geotechnical Considerations for Site Development, St. John’s Seminary, City of Camarillo, California, September 27, 2006.

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Qsc

590 295 0 590

n APPROXIMATE SCALE IN FEET SOURCE: Supplemental Discussion of the “Weber Fault”, Geolabs-Westlake Village, 2012

FIGURE 6.6-7 Fault Trench Location Map

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Geolabs Conclusions from Post-2006 Investigations and Reports

For the June 2006 previous fault investigation, Geolabs excavated and logged fault trenches FT-l, FT-2, and FT-3, to provide part of a continuous exposure completely across the westerly terminus of the APEFZ. As noted above, they concluded that one minor fault noted in FT-1 might require special foundation considerations, but recommended additional work. Results of additional fault trenching in 2008 confirmed the extent of the fault and they initially recommended special backfill and foundation treatments for a 150- to 200-foot-wide zone along the faults mapped. This was changed in the February 2012 report and a setback zone will be established where no habitable structures will be allowed. No other fault-related hazards were identified in terms of other defined clearly active faults within, or projecting toward, the proposed residential development area.

Due to the documented nature of movement on the Simi-Santa Rosa fault zone30 (as described above in Hitchcock and others), and on similar faults to the west (e.g., Springville fault in the Camarillo Hills) that came after the APEFZ map and several of the referenced engineering geology studies, it appeared that the potential for an active fault or zone of deformation through the proposed residential development area might still exist. Project site-specific fault investigations have been conducted to assess this potential.

Geolabs undertook a review of its past investigations related to zones of deformation31 and potential fault rupture32 both on the project site and to the east for residential tracts investigated in 1998 through early 2000. With regard to fault rupture two issues were addressed, primarily the Weber fault projection along the east-west canyon through the project site and also a fault of limited extent (so-called “setback fault”) along the southeast boundary of the project site zone with fault setbacks for Tract 5191. The setback fault is shown on Plate 1 to project southwest away from the project site and to not represent a hazard there.

The Weber fault as summarized in the Non-Site Specific Studies section above is within the APEFZ, though does not define the zone, and within the City of Camarillo Fault-Rupture Hazard Zone (FRHZ) covering this portion of the Simi-Santa Rosa fault zone. The Weber fault does define the north edge of the FRHZ and was published in 2003. Both the APEFZ and FRHZ have the same study requirements for faults within the zones. Geolabs February 2012 Weber fault report concludes that the “Subsequent

30 Hitchcock, C.S., S.C. Lindvall, J.A. Treiman, K.D. Weaver, J.G. Helms, and W.R. Lettis, 2001, FINAL TECHNICAL REPORT Paleoseismic Investigation of the Simi fault, Ventura County, California; National Earthquake Hazards Reduction Program Award Number 99-HQ-GR-0094, February 2001. 31 Geolabs, 2012a, “Zones of Deformation Tract Nos. 5191, 5247, and 5248 East of St. John's Seminary, City of Camarillo, California, dated January 31, 2012. 32 Geolabs, 2012b, “Supplemental Discussion of the "Weber fault " Preliminary Geotechnical Considerations for Site Development, St. John's Seminary, City of Camarillo, California, dated February 2, 2012.

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mapping and research led subsequent workers to abandon the location proposed by Weber” and that “trenching within St. John's Seminary near the original and subsequent proposed [Dibblee] faults did not encounter evidence of faulting.” As the February 2012 report Plate 1 and attached trench log FT-9 show, the Weber fault is coincident with faults mapped in FT-9 in what is called landslide material. However, because the trench was not excavated through the landslide plane, it could not be shown that this fault did not offset the underlying bedrock as well as the landslide, which might be the case if the Weber fault were active or potentially active. In addition, Treiman in FER-244 (Figure 2A) shows that there is a 40- to 50-foot gap in the trench 8a area within the canyon bottom where the Weber fault is mapped. Considering the information available there remains uncertainty as to the existence, location, and level of activity of the Weber fault. Geolabs suggests that in other areas where faults are seen within a landslide (although where no faults have been previously mapped), downward extensions of these faults are not seen below the landslide.

Zones of deformation are understood to be zones within which distributed ground deformation may occur due to underlying faults that experience very small offsets, or may not reach the surface, and folds that could uplift and tilt the ground surface causing cracking or small displacements. Geolabs indicates in its January 2012 report that “current policies of the City of Camarillo allow Zones of Deformation only where faults can be shown to experience less than six inches of displacement per seismic event.” In such situations structures can be built in these areas if strengthened foundations and special compacted fills (sometimes with geotextile layers) are utilized to absorb or attenuate the displacement at the base of the foundation or compacted fill mass so that minimal structural damage occurs. This construction method has been utilized in other areas of the City. Zones of deformation were defined in the three tracts to the east of the project site with the northern edges linked in a regular fashion continuously from east to west terminating at the project site east boundary north of the “setback fault,” but not continuing into the project site. Also, no zone of deformation was established in the areas north and south of the faults found in FT-1 and the offset trenches, which are planned to have a setback zone as well. Geolabs indicates that zones of deformation would be established in locations where faults “appear to be relatively older, or poorly developed, or discontinuous.”

Landslides

Two small landslides are mapped by Geolabs33 on the proposed project site. One (approximately 60 feet by 40 feet) is mapped along the northern property line and appears to be a shallow slump-type feature. The second was observed at the north end of trench FT-1 with an apparent shallow slump type scarp

33 Geolabs. Preliminary Geotechnical Considerations for Site Development, St. John’s Seminary, City of Camarillo, California, September 27, 2006.

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feature observed at approximately Station 6+60 and 7+20. This 12-foot by 120-foot feature appears to have formed on a form steep northwest-facing paleoslope in weathered Saugus Formation bedrock.

Geolabs also indicates that other geologic mapping suggests the presence of a large landslide along the east property line of the residential portion (not shown on the Geolabs Geologic Map), south of the main southwest-flowing drainage channel. Their trench FT-2 crossed a portion of the mapped landslide and Geolabs indicates that no landslide-type features were observed therefore indicating that the landslide does not appear to exist.

Five engineering geology/geotechnical borings (bucket augers with drive sampling and down hole logging by a geologist) were drilled at the northern edge of the of the residential portion of the site adjacent to the slope that descends into Calleguas Creek; this approximately north 67 degree east oriented slope is approximately 80 to 100 feet high adjacent to the proposed development area and near the borings (Figure 6.6-6). Geolabs'34 down hole observations within the borings indicate (1) bedding dips gently toward the south to southwest, (2) the slope is considered to be supported with respect to bedding planes, and (3) no through-going, adversely oriented faults, fractures, or joints were observed in the borings. Therefore Geolabs performed their slope stability analysis along one of two cross-sections oriented perpendicular to the north-facing topographic slope considering rotational failures through the Saugus Formation bedrock rather than along a planar feature(s) oriented out of the slope.

Slope stability calculations were performed by Geolabs on cross section B-B' (passing through boring B-1) considering rotational failures within the Saugus Formation bedrock on the 100-foot-high approximately 2.3 to 1 (horizontal to vertical) topographic slope (Figure 6.6-6). Geolabs concluded that (1) the existing slope has substandard factors of safety for static and pseudostatic (earthquake loading) conditions, (2) all failure surfaces under both conditions terminate within approximately 25 feet of the existing top of slope, and (3) building setbacks from the top of slope of approximately 60 feet should be anticipated during design of the project35.

Review of the boring logs indicates a few features that are oriented with a dip direction out of the north- facing slope, although there is no conclusion about the origin of these features or that these are adverse to the stability of the slope. In B-1 at a depth of 46 feet the following was described: “Grades to olive yellow clayey SILTSTONE to olive brown CLAYSTONE. Pervasively sheared, waxy, saturated; at 46 feet shears N70W/29NE” (roughly a 22-degree apparent dip). This attitude is not plotted on the geologic map. At 47 feet there are noted numerous high angle shears (N11E/35NW, N75W/44SW, N10W/45SW,

34 Geolabs, 2006b, Preliminary Geotechnical Considerations for Site Development, St. John’s Seminary, City of Camarillo, California, September 27, 2006. 35 Ibid.

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N8E/45NW) and through 55 feet deep there are multiple claystone interbeds dipping into the slope at 7 to 10 degrees. In boring B-3 at a depth of 46 feet there is a contact with sandstone over yellow-brown claystone with an attitude of N85E/17NW and at a depth of 77.5 feet a contact oriented N45E/9NW and described as moist “Sheared CLAY slickensided, pervasively sheared, in a 3-inch-thick zone to unsheared claystone.” These three features are at roughly elevation 300 feet, 266 feet, and 234 feet, respectively. Each of these features would project downward toward in the vicinity of the base of the north-facing slope.

Liquefaction and Shallow Groundwater

The state liquefaction potential map shows no areas of liquefaction affecting the proposed project site (Figure 6.6-4). Geolabs 2016 investigation included several hollow-stem auger borings into the alluvium. The findings from these borings have led to recommendations that, where possible, this material be removed to bedrock. The borings B18 and B19 indicate alluvium in the southwest area of the site as thick as 40 feet. No groundwater was encountered during our exploration. The Seismic Hazard Zone Report (CDMG, 2002, SHZR 054) indicates the historically highest ground water level is on the order of 70 to 80 feet deep in the alluvium adjacent to the property. Considering the lack of groundwater, and depth of historical groundwater, Geolabs considers there to be a low potential for liquefaction at the site.

Flooding

Based on Ventura County data, the proposed project site is not susceptible to flooding due to large or prolonged rain events or to earthquake-induced dam failure. The water tank just outside the proposed residential development area on the northeast (Figure 6.6-6) could fail in an earthquake event; the tank is about 140 feet in diameter and could hold in excess of one million gallons. Depending upon the nature of

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any failure (how large and which side of the tank) water could move to the west and/or south to reach the proposed project site.

Soils Engineering Considerations

Little is known about the soils engineering properties of the geologic units mapped by Geolabs36 and their report addresses primarily fault rupture, landslide (north boundary), and seismic design issues.

Within the proposed residential development area are five types of geologic units. Saugus Formation bedrock will generally have good to excellent engineering properties (good to excellent foundation support, not to slightly susceptible to consolidation, slightly to moderately erodible, and not to highly expansive). The four surficial units, artificial fill, colluvium/residual soil, alluvium, and landslide deposits will generally have poor to fair engineering properties (weak foundation support, susceptible to consolidation, moderately to highly erodible, and slightly to highly expansive).

In brief summary, the 2007 City review of the September 2006 report requested:

1. Drill and down-hole log borings in the City’s possible landslide, and recommend remediation if necessary.

2. Explain the origin and significance of shears mapped in previous borings on the northern slope, and confirm geologic structure (bedding/fracture/joint) orientations.

3. Provide slope stability analysis with factors of safety and seismic displacement values.

4. Address remaining (not specified) City Geotechnical Guidelines.

5. Review, sign, and seal grading plans.

The 2008 Geolabs report addressed items 1 through 3 with conclusions as mentioned above. Item 4 is assumed to require a complete and comprehensive preliminary geotechnical report covering design recommendations specific to the proposed development.

The 2016 Geolabs report further addressed slope stability analysis with factors of safety and seismic displacement estimations. The team performed a cross-sectional analysis of the geologic unit located on site. The slope stability analyses indicated that geologic materials on site have a minimum static factor of safety of 2.49. The estimated lateral seismic displacement is 6cm. This is slightly greater than the 5cm threshold that delimits the likelihood of no significant movement.

36 Ibid

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6.6.6 THRESHOLDS OF SIGNIFICANCE

In order to assist in determining whether a project will have a significant effect on the environment, the State CEQA Guidelines, City of Camarillo Threshold Guidelines (adopted from the State CEQA Guidelines, Appendix G) identify criteria for conditions that may be deemed to constitute a substantial or potentially substantial adverse change in physical conditions.

The following are thresholds under which a project may be deemed to have a significant impact if it would:

1. expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:

a. 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 or based on other substantial evidence of known fault? Refer to Division of Mines and Geology Special Pub. 42

b. strong seismic ground shaking,

c. seismic-related ground failure, including liquefaction, and

d. landslides.

2. result in substantial soil erosion, or the loss of topsoil,

3. 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;

4. 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.

6.6.7 ENVIRONMENTAL IMPACTS

The environmental impact analysis presented below is based on determinations made in the Notice of Preparation (NOP) for issues that were determined to be potentially significant with mitigation incorporated, or for issues identified by reviewing agencies, organizations, or individuals commenting on the NOP that made a reasonable argument that the issue was potentially significant (see Responses to NOP, Appendix 2.0).

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Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:

a. 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 or based on other substantial evidence of known fault? Refer to Division of Mines and Geology Special Publication 42.

Impacts

The proposed project is located partially within an established Alquist-Priolo Earthquake Fault Zone (APEFZ; see Figure 6.6-3) and partially within a City designated Fault-Rupture Hazard Zone (FRHZ) for surface fault rupture hazards. The APEFZ is defined based on active faults projected toward (one just into) the project site and the FRHZ is based on an approximately 400-foot-wide zone north of the trace of a fault that was discussed in Weber and others37 within the Simi-Santa Rosa fault zone presumed active or potentially active. If a fault(s) within these zones were to rupture the ground surface during a moderate to large local earthquake, overlying structures (e.g., buildings, utilities, and roads) could be severely damaged and persons could be injured, possibly fatally. In addition to ground rupture, this fault movement could (along with severe ground shaking) cause landslides and surficial slumps, ground uplift and differential ground deformation, ground tilting, and general ground cracking. Therefore, the potential for surface rupture (and related deformations) as a result of fault plane displacement during the design life of the project is potentially significant.

Based on the Geolabs 2006 study, only one “minor” fault (stated to be 6-inches of vertical offset in bedrock) was detected in a site-specific fault investigation; this is located in trench FT-1 in the southern one-third of the proposed development area. A follow-up study in 2008 determined that the fault would have a defined zone of deformation and a February 2012 report indicates a setback zone would be proposed without an associated zone of deformation. No further investigation was performed to locate the FRHZ/Weber fault and the APEFZ trenches (Geolabs and those to the east) did not cross the drainage where this fault is mapped by Weber and the City of Camarillo. Therefore, the potential for surface rupture (and related deformations) as a result of fault plane displacement along the Weber fault during the design life of the project is potentially significant.

37 Weber, F.H., Jr., Cleveland, J.E., Kahle, J.E., Kiessling, E.W., Miller, R.V., Mills, M.F. and Morton, D.M., 1973, Geology and mineral resources study of southern Ventura County, California: California Division of Mines and Geology Preliminary Report 14, 102 p., map scale 1:48,000.

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Construction

Due to the long periods between moderate to large earthquakes in this region, it is unlikely that ground rupture would occur within the proposed residential development area during the relatively short construction period. Also during this time (assuming normal construction and occupancy phasing) there would be minimal occupancy and impacts would be less than significant.

Operation

Following construction and occupancy of the buildings and operation of the infrastructure, structures and occupants of the development would be at risk for damage and injury, respectively, if they were within a resulting zone of fault rupture and deformation.

The project will be required to comply with all current City of Camarillo building and safety codes, which has adopted by reference the CBC, including setback requirements set forth in the Final Geotechnical Report. Compliance with these documents would reduce impacts to a less than significant level.

Mitigation Measures

No mitigation is required.

Residual Impacts

Impacts would be less than significant.

Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:

b. Strong seismic ground shaking.

Impacts

The proposed project site could be subject to strong ground shaking in the event of an earthquake originating along one of the faults listed in Table 6.6-1 (or another active or potentially active in the Southern California area; Figure 6.6-2). Strong seismic ground shaking potential hazard exists throughout Southern California and could pose a risk to public safety and property by exposing people, property, or infrastructure to potentially adverse effects (e.g., severe structural damage and building collapse). All structures shall be designed in accordance with the California Building Code (CBC) and applicable City codes to ensure safety in the event of an earthquake.

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In addition, within an active fault zone (such as the Simi-Santa Rosa) very strong ground shaking and amplification (near fault effects) can increase ground shaking levels and effects beyond normal building code design. Based on the presence of an active fault zone immediately east of the site (and possibly through the project site), the potential for amplified ground shaking during the design life of the project is significant.

Construction

Due to the long periods between moderate to large earthquakes in this region, it is unlikely that strong ground shaking would occur within the proposed residential development area during the relatively short construction period. Also during this time (assuming normal construction and occupancy phasing) there would be minimal occupancy. Therefore, impacts during construction would be less than significant.

Operation

It is likely that strong seismic ground shaking will occur over the course of the project’s lifetime and impacts could be potentially significant. The project will be required to comply with the California Building Code (CBC) and applicable City codes, as well as recommended stabilization measures set forth in the Final Geotechnical Report. Compliance with these documents would reduce impacts to a less than significant level. Following construction and occupancy of the buildings and operation of the infrastructure, structures and occupants of the development would be at a higher risk for damage and injury, respectively, if they were within a zone of amplified groundshaking. Impacts would be significant.

Mitigation Measures

No mitigation is required.

Residual Impacts

Impacts would be less than significant.

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Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:

c. Seismic-related ground failure, including liquefaction.

Impacts

Generally, liquefaction potential is greatest where the ground water level is shallow, and submerged loose, fine sands occur within a depth of about 50 feet or less below the ground surface. The project site is not within a liquefaction hazard zone as designated by the State of California and the City of Camarillo (Figure 6.6-4). Groundwater is not known to exist within the alluvium beneath the proposed residential development area; the potential for liquefaction on the project site is considered less than significant.

Construction

Due to the long periods between moderate to large earthquakes in this region which would be needed to cause liquefaction, it is unlikely that liquefaction would occur within the proposed residential development area during the relatively short construction period. Also during this time (assuming normal construction and occupancy phasing) there would be minimal occupancy. Therefore, impacts during construction would be less than significant.

Operation

The results of the liquefaction assessment indicate that significant liquefaction is not expected at the project site. Therefore, impacts related to liquefaction and lateral spreading would be less than significant.

Mitigation Measures

No mitigation is required.

Residual Impacts

Impacts would be less than significant.

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Expose people or structures to potential substantial adverse effects, including the risk of loss, injury, or death involving:

d. Landslides

Impacts

Landslides involve the vertical and lateral movement of large earth masses under by gravity (and possible initiated by earthquake forces). If landslides encroach into areas with structures, these structures can be severely damaged or destroyed, and occupants can be seriously injured if such failures were to occur without some advanced warning (e.g., slope cracking and/or structural deformation). State hazards maps for the proposed residential development area show the northern boundary and a portion of the site drainage feature to be susceptible to earthquake-induced landslides (Figure 6.6-4). There are known, relatively small landslides on and near the proposed residential development project site mapped by Geolabs, and the potential exists for grading to create unstable slopes that could lead to the formation of landslides. A previously mapped landslide (shown on City maps) was deemed not to exist by Geolabs studies.

All subsurface borings and slope stability analysis focused on the northern north facing slope area; rotational failures (failure through the Saugus Formation bedrock) were analyzed and failures along planar features (e.g., bedding, faults, and shears) were not considered. Some out-of-slope planar features were noted in the boring logs. In their 2016 study report Geolabs concluded based on their analysis of the northern north facing slope that it has both static factors of safety (greater than 1.5) and seismic deformations (5 to 15 centimeters) that would be at or above acceptable values for residential construction areas and no setbacks into the project from the top of the existing slope are required. They recommend that foundation/slab-on-grade system for the residential structures to be reinforced in a manner to account for some tensional stress. This type of analysis has not been reviewed and commented on by the City and therefore, the potential for impacts from earthquake-induced landslides or other landslides is considered potentially significant.

Construction

During the grading process temporary cuts and fills may be made prior to completing all stabilization activities; this can result in slope failures that can range from a nuisance to something affecting adjacent (off-site) properties and structures. Due to the long periods between moderate to large earthquakes in this region which would be needed to cause a landslide, this type of failure is not considered significant during the construction period. Therefore, impacts would be less than significant during construction.

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Operation

Following construction and occupancy of the buildings and operation of the infrastructure, structures and occupants of the development would be at a higher risk for damage and injury, respectively, if small or large landslides were to be triggered either by earthquakes or by other factors such a heavy rainfall or underground water sources. The areas nearer to the approximately 2,000-foot-long northern north-facing slope are considered to have the highest risk based on Geolabs analysis and the presence of some planar features logged in borings that may be oriented out of slope. Recommendations from the 2016 Geolabs report includes the removal of colluvium (Qc), portions of the alluvium (Qal), landslide debris (Qls) existing fill materials, and weathered bedrock in the development area should be removed to firm bedrock or competent alluvium and replaced with properly compacted engineered fill. There are six lots in the vicinity of borings B18 and B19 that extend into the area of alluvium. The area of these lots should have the alluvium removed to bedrock. Implementation of the stabilization improvements included in the Final Geotechnical Report, as well as the standard plan checking requirements which would ensure stabilization of proposed cut slopes that are potentially unstable. Impacts would be less than significant.

Mitigation Measures

No mitigation is required.

Residual Impacts

Impacts would be less than significant.

Result in substantial soil erosion, or the loss of topsoil.

Impacts

Construction activity associated with large-scale grading can result in wind, gravity, and water driven erosion of earth materials (soils and geologic units) if soil is disturbed, exposed, or stockpiled. After construction and covering the sites with pavement and landscaping, this potential impact is substantially reduced.

Due to the extent of grading there could be a substantial loss of topsoil on the project site, which would convert what remains of the site agricultural land to urban use, necessitating topsoil removal as part of geotechnical remediation. Other areas remove the existing topsoil from use by covering it with roadways and other residential uses. Therefore, impacts would be potentially significant during construction.

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Construction

To prevent soil erosion as part of the project, the applicant must comply with conditions under the National Pollutant Discharge Elimination System (NPDES) Permit set forth by the Regional Water Quality Control Board (RWQCB), and to prepare and submit a Storm Water Pollution Prevention Plan (SWPPP) to be implemented during project construction (see Section 6.8, Hydrology and Water Quality). The SWPPP Best Management Practices (BMPs) ensure that erosion and sediment transport are minimized to assure that potential off-site impacts during construction would be reduced to less than significant. In addition, the applicant would be required to adhere to Ventura County Air Pollution Control District Rule 55 – Fugitive Dust,38 which would further reduce the wind erosion impacts to less than significant.

Operation

After construction impacts associated with soil erosion or the continuing loss of topsoil would be considered less than significant.

Mitigation Measures

No mitigation is required.

Residual Impacts

Impacts would be less than significant.

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; and 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.

Impacts

The potential impacts from landslides, liquefaction, and lateral spreading are discussed in the subsections above. Subsidence and ground collapse are not issues at the project sites. Soils-engineering properties of the geologic units have been mapped by Geolabs.39 There are five geologic units; four surficial and one

38 Ventura County Air Pollution Control District Rule 55 – Fugitive Dust, Adopted 6/10/08. 39 Geolabs. Geotechnical Investigation, Proposed Subdivision of a Portion of St. John's Seminary, City of Camarillo, California, August 31, 2016.

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bedrock unit within the proposed residential development area. Without engineering modification, the surficial units at the project site would be consolidation prone, erodible, and would make poor foundation materials. These conditions could lead to damage for any structures placed over these materials. In general the bedrock has suitable characteristics with regard to erosion, consolidation, and foundation stability. Expansive soils units are found in the Saugus formation bedrock that could cause damage to foundations and walls due to repeated drying and wetting (shrink and swell). Therefore, geologic, soils, and geotechnical impacts would be potentially significant during construction and operations.

Construction

During grading, soil conditions can impact equipment operations and personnel safety if geologic or soil units are made unstable by excess rainfall, surface runoff, infiltration, erosion, or equipment vibration, particularly in hillside terrain. This could result in damage to equipment, injury to personnel, and off-site impacts to property and/or individuals. However, the CBC regulates excavation, foundations, and retaining walls; contains specific requirements pertaining to site demolition, excavation, and construction to protect people and property from hazards associated with excavation cave-ins and falling debris or construction materials; and regulates grading activities, including drainage and erosion control. As such, observation of all State and local safety regulations during all phases of construction operations would ensure that impacts would be less than significant.

Operation

Following construction and occupancy of the project sites, the long-term stability (and instability) of soil and geologic units can impact the stability of structures, and natural and manufactured slopes. Without proper engineering remediation, unstable soils and bedrock can be adversely affected by excess rainfall, surface runoff, infiltration, erosion, and structural loading. Foundation or slope failures, particularly in hillside terrain, could result in damage buildings, roadways, slopes, and utilities as well as serious injury to occupants and visitors. However, implementation of the stabilization improvements included in the Final Geotechnical Report, as well as the standard plan checking requirements which would ensure stabilization of proposed cut slopes that are potentially unstable. Impacts would be less than significant.

Mitigation Measures

No mitigation is required.

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Residual Impacts

Impacts would be less than significant.

Have soils incapable of adequately supporting the use of septic tanks or alternative wastewater disposal systems where sewers are not available for the disposal of wastewater.

Impacts

Septic tanks would not be used in the proposed project. The project lies within Camrosa Water District’s service area, and the proposed project would be required to connect to the nearest existing Camrosa sewer line south of the proposed project at the intersection of Upland Road and Hillridge Drive. No impact would result.

Mitigation Measures

No mitigation is required.

Residual Impact

No impact would occur.

6.6.8 CUMULATIVE ANALYSIS

The potential for cumulative impacts associated with geology and soils was assessed, based upon consideration of the proposed project and related projects in the City of Camarillo. These related projects are identified in Section 5.0, Cumulative Scenario.

Impacts

Geotechnical impacts tend to be site-specific rather than cumulative in nature and any development occurring within the City of Camarillo would be subject to, at a minimum, uniform site development and construction standards relative to seismic and other geologic conditions that are prevalent within the region. As project development and each related project element would have to be consistent with recommendations contained in each project's future preliminary geotechnical investigation report and be designed in accordance with the CBC, cumulative impacts associated with known geologic conditions would be less than significant.

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Impacts regarding surficial deposits, namely erosion and sediment deposition, can be cumulative in nature within a watershed. Development of the proposed project site and related projects has the potential to impact areas off site including water bodies. However, with implementation of a SWPPP, as required by the NPDES permit, cumulative erosion within the watershed would not exceed natural levels, and significant cumulative impacts related to erosion would not occur.

6.6.8.2 Mitigation Measures

No addition mitigation is required.

6.6.8.3 Residual Impacts

There would be no residual impacts.

6.6.9 CONSISTENCY WITH THE CITY OF CAMARILLO GENERAL PLAN

The City of Camarillo General Plan Safety Element provides goals, objectives, and policies for geology and soils, some of which apply to the proposed project. An analysis of the consistency of the St. John’s Seminary Residential Community Project with each of the General Plan components is provided below.

Geologic Hazards

Goal SAF-2: A community that is aware of and has planned for existing and potential geologic and seismic hazards.

Objective SAF-2.1: Decrease the potential risk associated with geologic hazards within the City of Camarillo

Policy SAF-2.1a: Minimize geologic hazards by identifying and addressing potential hazards during the planning and engineering of proposed development and/or improvement projects.

Policy SAF-2.1b: Require the preparation of a geologic/geotechnical investigation (performed by a Certified Engineering Geologist and/or a Geotechnical Engineer) for all new development or development projects located in areas of potential hazards. That investigation should include adequate analysis and appropriate mitigation of potential hazards to the satisfaction of the City Engineer or their designee. Special consideration should be given to terrain, soils, slope stability, and erosion issues, where applicable.

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Analysis

Policy SAF-2.1a: The potential impacts from geologic hazards (soils, landslides/mudslides, and subsidence) are discussed in section 6.6.7 Environmental Impacts above. The project would be consistent with this policy of the General Plan.

Policy SAF-2.1b: To date there has been a preliminary site investigation (2006) followed by City review comments (2007) and a response to the review (2008) regarding slope stability. There shall be an ongoing applicant/City consultation related to slope stability analysis and landslide potential; further analysis is planned (see Mitigation Measure 6.6-2) and the City has adopted or will adopt the 2013 CBC. INCLUDE LATER REPORTS AND THE MOST RECENT CBC.

In regards to subsidence, the Ventura County Area Map has indicated no known areas of subsidence located on project site.

Summary

The proposed project is consistent with the City of Camarillo General Plan.

6.6.9.2 Seismic Hazards

Goal SAF-2: A community that is aware of and has planned for existing and potential geologic and seismic hazards.

Objective SAF-2.2: Reduce the potential effects of seismic hazards on existing and new developments within the City of Camarillo.

Fault Rupture

Policy SAF-2.2a: Review development projects involving construction within Earthquake Fault Hazard Zones (as depicted on the State of California, Earthquake Fault Hazards Map for County of Ventura in accordance with the requirements of the Alquist-Priolo Earthquake Fault Zoning Act and policies and criteria established by the State).

Policy SAF-2.2b: Consider the designation of land located within Earthquake Fault Hazard Zones and potentially active fault areas for less dense or intensive uses, such as Open Space or Agricultural, where feasible.

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Policy SAF-2.2c: Design roadways, streets, highways, utility conduits, and oil and gas pipeline, to avoid crossing active faults where feasible. When such location is unavoidable, the design should include measures to reduce the effects of any fault movement as much as possible.

Policy SAF-2.2d: Locate new critical facilities, special occupancy structures, or hazardous materials storage facilities outside of active fault zones unless demonstrated that the facility is not subject to fault rupture hazard.

Seismic Shaking

Policy SAF-2.2e: Continue to adopt the most current version of the California Building Code to ensure the use of the most up to date seismic requirements within the State of California.

Policy SAF-2.2f: Require roadway engineering standards that meet or exceed seismic requirements of the California Building Code to reduce potential damage and maintain emergency access in the event of an earthquake.

Liquefaction

Policy SAF-2.2g: Require additional analysis for development within areas susceptible to secondary seismic impacts (liquefaction, landsliding, subsidence, etc.) to determine the potential risk to these hazards and identification of mitigation measures, to the satisfaction of the City Engineer or their designee.

Analysis

Policy SAF-2.2a: The potential impacts from Earthquake Fault Hazard Zones as depicted in the Earthquake Fault Hazards Map and in accordance with the requirements of the Alquist-Priolo Earthquake Fault Zoning Act (soils, landslides/mudslides, and subsidence) are discussed in section 6.6.7 Environmental Impacts above. The project would be consistent with this policy.

Policy SAF-2.2b: Multiple site-specific investigations to determine fault locations have been completed within the St. Johns Residential Community area and for projects to the east; more investigation and/or additional design measures may be required (see Mitigation Measure 6.6-1) prior to final development plan approvals. No development would be allowed on active fault lines and no existing structures would remain within the development area to be modified. The project would be consistent with this policy.

Policy SAF-2.2c: Multiple site-specific investigations to determine fault locations have been completed within the St. Johns Residential Community area and for projects to the east; more investigation and/or

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additional design measures may be required (see Mitigation Measure 6.6-1) prior to final development plan approvals. No development would be allowed on active fault lines and no existing structures would remain within the development area to be modified. The project would be consistent with this policy.

Policy SAF-2.2d: Multiple site-specific investigations to determine fault locations have been completed within the St. Johns Residential Community area and for projects to the east; more investigation and/or additional design measures may be required (see Mitigation Measure 6.6-1) prior to final development plan approvals. No development would be allowed on active fault lines and no existing structures would remain within the development area to be modified. The project would be consistent with this policy.

Policy SAF-2.2e: Building regulations are specified in of the Camarillo Municipal Code, including adoption of the 2013 California Building Code (CBC) (the CBC is based on the 2012 International Building Code [IBC]). Standard residential, commercial, and light industrial construction is governed by the CBC, which the City has amended and provided additions to. The project would be consistent with this policy.

Policy SAF-2.2f: Roadway construction would be required to meet all building regulations specifically in the California Building Code in order to minimize seismic hazards to emergency access. Roadway construction plans is subject to review, and must be approved prior to implementation and permits. The project would be consistent with this policy

Policy SAF-2.2g: Prior to approval of tentative tract maps, a preliminary geotechnical investigation report shall be prepared for the specific design elements of the proposed project. The City will require analysis and technical reports on soils and other geotechnical factors which would include adequate analysis of potential hazards. The project would be consistent with this policy.

Summary

The proposed project is consistent with the City of Camarillo General Plan.

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