ARCHIVED REPORTS LEC APPLICATION FOR CERTIFICATION

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including,but not limited to,cementing agents,clay-welding of soil particles,silt bonds,clay bonds,clay bridges,and capillary tension. Soils found most susceptible to collapse include loess (fine-grained,wind- deposited soils) deposits, valley alluvium deposited within a semi-arid to and climate, and residual soil deposits. Collapsible soils are generally associated with dry regions(NAVFAC,1982). Based on the observations during the subsurface exploration, the collapse potential of soils beneath the site is anticipated to be low due to shallow groundwater. 4.3.3 Landslides and Slope Stability Based on the flat topography on the site, the potential for landslides and slope stability failures on the site are anticipated to be low. No areas of active or inactive landslides on the project site were identified during our site reconnaissance or review of aerial photographs. 4.3.4 Subsidence Subsidence can be a natural or man-made phenomena resulting from tectonic movement, consolidation, hydrocompaction, groundwater extraction, or decomposition of organic material. The USGS International Survey on Land Subsidence Database indicates subsidence in the Sacramento to Stockton area is associated with groundwater extraction. Based on the proximity to the bay, relatively constant groundwater depth for the past 30 years, and the proposed reuse of water from the City of Lodi's White Slough Water Pollution Control Facility(WPCF) rather than development of groundwater resources, the future land subsidence due to groundwater pumping associated with this project is anticipated to be low. 4.4 FAULTING AND SHEAR ZONES The site is not located within the Alquist-Priolo Earthquake Fault Zoning Act Special Publication. The Alquist-Priolo Earthquake Fault Zoning Act was passed in 1972 to mitigate the hazard of surface faulting to structures planned for human occupancy. No faults have been mapped as crossing the site. The nearest mapped active fault is the Greenville Fault,located approximately 30 miles to the southwest of the site. 4.5 SEISMIC CONSIDERATIONS According to the Fault Activity Map of California and Adjacent Areas, (California Division of Mines and Geology, 1994) faults located in the proximity of the project are part of the San Andreas Fault System. The San Andreas system is active, with displacements occurring during historic time. The nearest known active fault is the Greenville Fault,located approximately 30 miles to the southwest of the project site. Strong earthquakes generated along any of the California faults may affect the project area depending on the characteristics of the earthquake and the location of the epicenter. According to the United States Geologic Survey (USGS) Seismic Hazard Curves and Uniform Hazard Response Spectra program version 5.0.7,upper and lower level earthquake peak ground accelerations are estimated to be 0.19g and 0.09g respectively. An upper level earthquake motion is defined as being the ground motion with a 10% probability of being exceeded in 50 years, while a lower level earthquake is defined as being the ground motion with a 50%probability of being exceeded in 50 years. Peak ground accelerations associated with the maximum considered earthquake (MCE), defined in the 2007 California Building Code as a ground motion with a 2% probability of being exceeded in 50 years, is estimated to be 0.35g at the site. Earthquake magnitudes contributing to this peak ground acceleration are presented in the table below. Peak ground acceleration associated with a maximum probable earthquake (MPE), defined as the maximum earthquake that appears to be reasonably expectable to occur in a 100 year interval(Kramer,1996),is estimated to be 0.11g. Historically, some faults known to produce large earthquakes in the region are the Calaveras, Hayward, Project No.5593-01-05 C A R LT O 7/29/2008 7 Engineering Inc . NCPA GFS.doc