SITE INFORMATION AND CORRESPONDENCE_FILE 2

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Valley Motors - 3 - ``� 27 January 2014 800 E. Main St. Stockton, San Joaquin County (total depth 73' bgs) as shown in Figure 2. Well and boring construction details are presented on Table 3. Groundwater depths to water are presented in Table 4 and the December 2013 potentiometric water surfaces are mapped in Figure 4. 10)A prediction of when WQOs will be met was not provided by Upgradient Environmental Consultants (UEC). Central Valley Water Board staff calculated the time to reach WQOs in Table 5 based on the TPHg data for the source area monitoring well VM-2. The trend line shows 40 years to reach WQOs based on the entire data set. UEC did conclude that based on groundwater monitoring, the residual groundwater plume will not migrate beyond the current conditions. 11)The Site appears to meet the general criteria of the State Water Resources Control Board's (State Water Board's) Low-Threat Underground Storage Tank Case Closure Policy (LTCP) as follows: • The site is within the service area of a public water system. The site is within the service area of the California Water Service (CWS). • The release consists only of petroleum. Although elevated lead was detected in soils at 10.5 feet below ground, lead was tested in groundwater and was reported at <10 ug/L. • The release has been stopped. The UST system was removed in October 1990. • Free product has been removed to the maximum extent practicable. Free product was not encountered. • A Site Conceptual Model has been developed. • The secondary source has been removed to the extent practicable. Secondary source was removed by soil vapor extraction during a pilot study, and groundwater monitoring through 2013 has shown that additional remediation was not necessary to further reduce groundwater concentrations to levels where natural degradation will achieve cleanup in a reasonable time frame. Based on stable to decreasing concentrations in groundwater, UEC concluded in December 2013 that there does not appear to be a significant secondary source remaining that would reverse the declining trends. • Soil and groundwater have been tested for MTBE and the results reported in accordance with Health and Safety Code section 25296.15. Soil and groundwater have been tested for MTBE; MTBE was detected in three wells in 1996 and one well in 2001. Maximum MTBE in VM-1 was 1,140 ug/L in July 1996, which declined to 21 ug/L in June 2001 in VM-3. • A nuisance, as defined by Water Code section 13050 does not exist at the site. No nuisance exists from the release at this Site. 12)The Site meets the State Water Board's LTCP's Groundwater media specific criteria, scenario 1 as follows: