ARCHIVED REPORTS_DRAFT ENVIRONMENTAL IMPACT REPORT

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Because the project would be located on relatively flat land in the San Joaquin Valley, and a review of geologic maps and literature indicates the project site is not located within or near a landslide hazard area,this issue will not be further addressed in this Draft EIR. RECREATIONAL GEOLOGIC FEATURES Recreational geologic resources typically include areas of rock or mineral collecting,volcanoes, surface hydrothermal features,or surface expression of geologic features unique enough to generate recreational interests of the general public (e.g.,natural bridges, caves, features associated with glaciation, and geomorphic features such as waterfalls, cliffs, canyons, and badlands). Based on a review of available geological literature, topographic maps, and a field visit to the site,there are no known recreational geologic resources associated with the project area. REGIONAL SEISMICITY AND FAULT ZONES The northern San Joaquin Valley has generally not been seismically active in the last 10,000 years. Most faults in the project region with known or estimated activity during the Holocene epoch are generally located in the Bay Area, approximately 40 miles to the west, and lie within the Coast Ranges geomorphic province, as shown in Table 4.7-1. Table 4.7-1 Regional Fault Activity During the Holocene Epoch Faults Active in Holocene Time in Distance from Probable Maximum Location the Vicinity of the Project Area Project Area Magnitude' Great Valley 23 miles 6.7 Coast Ranges,western margin of San Joaquin Valley Greenville/Marsh Creek 38 miles 6.9 Coast Ranges,Bay Area Ortigalita 40 miles 6.9 Coast Ranges,Bay Area Calaveras 60 miles 6.8 Coast Ranges,Bay Area Hayward 63 miles 7.1 Coast Ranges,Bay Area Concord 63 miles 6.9 Coast Ranges,Bay Area Green Valley 65 miles 6.9 Coast Ranges,Bay Area San Andreas(1838 Event) 65 miles 7.9 Coast Ranges,Bay Area 'A measure of earthquake size calculated on the basis of seismic moment called Moment Magnitude(Mw).The earthquake magnitude values here are expressed as Richter scale values.The Richter scale is a logarithmic scale that expresses the magnitude of an earthquake in terms of the amount of energy generated,with 1.5 indicating the smallest earthquake that can be felt,4.5 an earthquake causing slight damage,and 8.5 a very damaging earthquake. Source:Jennings 1994,Helley and Harwood 1987,Kleinfelder 2005 The fault closest to the project site that has been active during the Holocene epoch is the Great Valley Fault System, a series of blind-thrust faults located along the western edge of the San Joaquin Valley. A number of earthquakes have been attributed to this fault system during the last 100 years, including the 1892 Vacaville— Winters earthquake (although some researchers dispute the Great Valley fault as the source for this earthquake), the 1881 West San Joaquin Valley earthquakes,the 1983 Coalinga earthquake, and the 1985 Kettlemen Hills earthquake (Toppozada 1987,Kleinfelder 2005). Only the 1983 Coalinga earthquake resulted in surface ground rupture. EDAW Manteca WQCF and Collection System Master Plans EIR Geology, Soils,and Seismicity 4.7-2 City of Manteca