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1 - Mr James Barton ' July 30, 2004 Page 2 ' the Wards site The remedial system was put into full operation in November 1999, and was in operation until December 2000 when the auto service center and remedial system were shut down due to Wards filing bankruptcy During its operation, the Wards remedial system removed ' approximately 8,000 pounds of hydrocarbons Groundwater monitoring at the Wards site has been conducted since 1993 Groundwater ' monitoring activities for the Wards site and the Unocal site, for the most part, were conducted simultaneously and coordinated by the various consultants representing the two entities The former Wards site was redeveloped into a restaurant The former Wards building was demolished and the parking lot raised and resurfaced Well casing elevations and locations ' were resurveyed for all wells Former Unocal Station No 5098 operated at 5606 Pacific Avenue, Stockton, California between ' approximately 1955 and 1985 In 1985, the station was closed and the USTs removed After completing soil and groundwater Investigations, Unocal excavated approximately 6,000 cubic yards (yds3) of soil from the site in 1988 The excavated soil was aerated on-site, and based on ' the analytical testing results, 5,800 yds3 of the aerated soil were reused as fill, and 200 yds3 transported off-site for disposal On August 25, 1989, the RWQCB Issued a letter for the Unocal site confirming that the soil contamination at the site has been adequately cleaned up, but, that the extent of groundwater impact had yet to be defined Between 1992 and 1999, additional soil and groundwater ' investigations associated with the Unocal site were conducted San Joaquin Delta College (Delta College) operated a groundwater extraction well identified as the "Robinhood Irrigation Well" (RIW) (also know as "Delta College Well") The RIW was ' located southwest of the intersection of Robinhood Drive and Pacific Avenue The RIW was installed in 1950 and was reported to be 322 feet deep with perforations in multiple zones beginning at depths as shallow as 40 feet below ground surface (bgs) According to the Water ' Well Driller's Report for the RIW, "no strata were sealed against pollution" Groundwater from the RIW was formerly used to irrigate portions of Delta College's campus Groundwater monitoring data for the site show that historical pumping of the RIW Influenced and changed the natural direction of groundwater flow in the area from easterly, to south southwesterly, towards the RIW e Sampling of the RIW by Unocal and/or Wards for dissolved petroleum constituents began in 1997 and continued through June 15, 2000 In August 2000, Delta College students and staff complained of a gasoline odor in water derived from the RIW As requested by the RWQCB, the RIW was taken out of service as of 6 00 AM, August 22, 2000 and RIW was abandoned in August 2001 In February 2001, seven new wells (MW-18D, MW-23S, MW-23D, MW-24S, MW-24D, MW-25S, and MW-25D) were installed to assess the vertical and lateral extent of hydrocarbon- impacted groundwater at the Unocal site and in the vicinity of the RIW In September 2001, four additional wells (MW-8D, MW-9, AS-26 and MW-27) were Installed to further define vertical and ' J 1Pro}ecW0694M5098 293TinaRReportsM98 Weil Results Report doc Ovp Y- ,s of Ex(ehenc- ire ,-nvuoimneWal Service