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URS <br /> Mr. Ross Atkinson <br /> Regional Water Quality Control Board—Central Valley Region <br /> May 20,2011 Page 2 of 10 <br /> samples confirmed the presence of VOCs where the total VOC concentration in each of the vapor <br /> extraction wells was less than 5 ppmV. Based on these results,VOC constituents could be present in <br /> groundwater. To assess the presence or absence of VOC constituents in the groundwater,three <br /> groundwater monitoring wells were installed at the site on June 12, 2006. Following the installation of <br /> groundwater monitoring wells, groundwater samples were collected quarterly and analyzed for VOCs. <br /> Mr. Ross Atkinson (RWQCB)requested that groundwater samples be collected and analyzed for metals <br /> and general minerals (only total dissolved solids [TDS] after the first event) starting the fourth quarter of <br /> 2006 (4Q06). <br /> Based on the 4Q06 monitoring results, RWQCB sent a letter to Tandy Corporation dated <br /> February 20, 2007, which identified eight constituents (TDS, aluminum, arsenic, barium, iron, lead, <br /> manganese, and nickel)that exceeded water quality goals, and requested Tandy Corporation to <br /> investigate the extent of groundwater impacts. In a meeting on May 24, 2007, Mr. Atkinson concurred <br /> with the recommendation in the Quarterly Monitoring Report dated April 30, 2007,to suspend the <br /> groundwater monitoring activities for VOCs, and also agreed that additional groundwater monitoring <br /> results were needed before completing additional groundwater investigation activities. <br /> In a meeting on November 1,2007, Mr. Atkinson specified that the following two items were needed <br /> before RWQCB could decide whether to conduct further investigation, continue groundwater monitoring <br /> activities, or to close the site: (1)information as to whether a local water service company provides <br /> water to residents in the area near the site, and(2)the results of a well search following receipt of <br /> RWQCB's authorization to complete the well search. The following information regarding local water <br /> service company, California Water Service (CWS),was provided to RWQCB in an e-mail message sent <br /> on November 13,2007: CWS provides water service along Downing Avenue, along Mourfield Avenue, <br /> and along a portion of Clayton Avenue (from the intersection of Clayton Avenue and Mourfield Avenue <br /> to approximately halfway towards the intersection of Mourfield Avenue and Turnpike Road) (note: CWS <br /> does not provide water service along Turnpike Road). <br /> RWQCB sent a letter dated April 20, 2011,to Tandy Corporation requesting the submittal of a technical <br /> report that provides the basis for our request for site closure. b <br /> FIELD ACTIVITIES <br /> Soil <br /> Installation of the passive SVE trench generated excess soil.This excess soil was transported to <br /> permitted disposal facilities. Prior to disposal, grab samples of the excess soil were collected to <br /> characterize the soil for disposal. The soil samples were composited by the analytical laboratory and <br /> analyzed for total petroleum hydrocarbons, VOCs, semi-volatile organic compounds, and metals. <br /> Groundwater <br /> Quarterly groundwater monitoring has been conducted since June 2006 (2Q06). Groundwater samples <br /> were collected from three monitoring wells (MW-1, MW-2, and MW-3) each quarter from June 2006 <br /> (2Q06)to March 2011 (1 Q 11). Groundwater samples were analyzed for VOCs from June 2006 (2Q06) <br /> H:AWprocess\25532\WorldEntegirise\ClosureA052011 doc <br />