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City of Pleasanton—Hidden Canyon Residences and Preserve Geology, Soils, and Seismicity Draft EIR 3.6-6 FirstCarbon Solutions https://adecinnovations.sharepoint.com/sites/PublicationsSite/Shared Documents/Publications/Client (PN-JN)/2148/21480016/EIR/3 - Draft EIR/21480016 Sec03-06 Geology.docx approximately 0.7 mile east of the project site, the Hayward Fault approximately 6.2 miles west of the project site, the Greenville Fault approximately 12.2 miles northeast of the project site, and the Concord-Green Valley Fault located approximately 13.3 miles north of the project site. Other lesser- known faults are located east of the project site including the Pleasanton Fault, the Verona Fault, and the Dublin Fault located around Interstate 580 (I-580). The four major fault lines in proximity to the project site are discussed in further detail below. Calaveras Fault The Calaveras Fault is a major right lateral strike-slip fault in the eastern San Francisco Bay Area extending in a northwest direction about 93 miles from San Ramon, California in the north to Hollister, California in the south where it converges with the San Andreas Fault. The Calaveras Fault is divided into four segments characterized by having differences in slip rates, recurrence intervals, and paleo seismic events. The closest segment to the project site is the Northern Calaveras segment approximately 0.7 mile east of the project site that begins north of the Calaveras Reservoir and transects the Tr i-Valley and San Ramon Valley areas consisting of a slip rate of approximately 5-6 mm/year with sparse seismicity, and capability of producing surface rupture during moderate to large earthquakes. The northern segment has a reoccurrence interval between approximately 125 and 850 years with paleo seismic events that occurred between AD 1425 and AD 655 and between AD 1861 and AD 1160 both in the Diablo Ranges south of Sunol.12 Recent notable earthquakes generated from the Calaveras Fault include the 1984 Morgan Hill earthquake with a magnitude of 6.3 on the Richter Scale, the 1979 Coyote Lake earthquake with a magnitude of 5.8, and a magnitude 6.2 in 1858 with severe shaking recorded in Pacheco, California. Hayward Fault The Hayward Fault is a major right lateral strike-slip fault between the eastern margins on the San Francisco Bay and western front of the East Bay Hills which strikes in a northwest direction from eastern San Jose in the south to San Pablo Bay in the north totaling approximately 66 miles in length. The fault has three sections with the closest section being the Southern Hayward section approximately 6.2 miles west of the project site that is characterized as having a minimum horizontal displacement slip rate of 5mm/year with about six to eight paleo seismic events in the past 2,100 radiocarbon years and an average reoccurrence interval of 150-205 years. The last maximum event generated by the Southern Hayward section was the 1868 Hayward earthquake producing a magnitude of 7.0 on the Richter Scale with surface rupture extending 32 miles north of the epicenter.13 Greenville Fault The Greenville Fault is a major right lateral strike-slip fault that strikes in a northwest direction from San Antonio Valley in the Diablo Ranges in the south and ends on the northeastern side of Mount Diablo, traversing approximately 56.5 miles in length. The Greenville Fault is divided into four segments based on geomorphic expression and structural character with the closest segment being the Marsh Creek-Greenville segment approximately 13.3 miles northeast of the project site which 12 Bryant, W.A., S.E. Cluett. 1999. Fault number 54a, Calaveras Fault Zone, Northern Calaveras section, Quaternary fault and fold database of the United States. March 4. 13 Bryant, W.A., S.E. Cluett. 2000. Fault number 55a, Hayward Fault Zone, Northern Hayward section, Quaternary fault and fold database of the United States. December 14.