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Ms.Jessica Hardy October 25, 2000 Page 2 The well damage and burial at the former GP facility were reported to the California Regional Water Quality Control Board,Central Valley Region (RWQCB) in the semiannual groundwater monitoring report submitted in July 1995. No groundwater monitoring samples have been collected from well BC-9 since December 1988 and from well BC-10 since March 1995. Well BC-11 has not been monitored since January 1994. On February 4, 2000,Brown and Caldwell submitted a Work Plan to the RWQCB to locate and,if possible,rehabilitate monitoring wells BC-9,BC-10 and BC-11. The RWQCB conditionally approved this Work Plan in a letter dated April 21, 2000. Well Location and Redevelopment At the time of their installation, a California-licensed surveyor established the latitudinal and longitudinal coordinates of wells BC-9,BC-10, and BC-11. On April 14, 2000, Brown and Caldwell determined the approximate locations of these wells, carefully removed the soil overburden from the wellheads, and assessed the well's condition. The well information log in Attachment A documents our assessment. The containment box and seal for well BC-9 appeared to be in good condition,based on a visual inspection. A two-inch diameter submersible pump was dropped down well BC-9. This pump did not encounter any obstructions as it was lowered down the well. The total depth of well BC-9 was established at 41.15 feet below ground surface (bgs). The depth to groundwater was measured at 40.90 feet bgs. With only 0.25 feet of water available, it was not possible to redevelop well BC-9 or collect a groundwater sample. Well BC-9 will be redeveloped at a later date if and when a minimum of one foot of standing groundwater is measured in the casing. Brown and Caldwell also determined that the containment box, seal and casing of well BC-10 were in good condition. Well BC-10 was found to extend to 64.80 feet bgs, withstanding water measured at 41.24 feet bgs. Because well BC-10 contained sufficient water,appeared to be in good condition,and produced clear water during sampling, it was not redeveloped. A sample was collected from well BC-10 following the methods used during semiannual groundwater monitoring events at this site. A groundwater sample collection record for well BC-10 is included in Attachment A. 10/25/00 m:%I 8420\Iawe \18420-002\well location 1.doc/g/bd