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KEI-P89-1104 .QR3 October 31, 1991 Page 6 diameter casing for the full depth of the well, using a tremie tube. In addition, it was subsequently proposed to conduct a down- hole camera survey of the six-inch diameter well casing to deter- mine the casing depth and overall condition of the casing. In late June, 1990, the down-hole camera survey was conducted at the site. A video tape recording of the survey was made with one copy apparently submitted to the SJCPHS from Purviance Drillers, Inc. The results of the down-hole camera survey and additional field inspection by Purviance Drilling indicate the following: 1. Inner casing is 6-5/8 inches O.D. X 12-gauge tarred and belled at 20 foot 3oints, and extends from surface to a depth of 115 feet below grade; 2 . No breaks, holes, or perforations were observed; 3 . Outer casing is ten--inch diameter extending to an unknown depth; 4 . Annulus between six-inch and ten-inch casings is filled with neat cement, and the extent and quality (lack of voids) of the neat cement is unknown; 5. Standing water was at a level at 54 . 5 feet below grade; 6 . At a depth of 125 feet below grade, a well size reduction was indicated when the camera could not pass; and, 7 . Total well depth was measured at 133 feet below grade. A well destruction work plan (KEI-P89-1104 .P4 dated July 19 , 1990) was prepared by KEI for the satisfactory destruction of the presently abandoned water well. Special tools are required for this work, and Purviance Drillers are actively working towards completion of tool construction. Once the special tools have been constructed, KEI is prepared to destroy the existing abandoned water well. On October 10 and 11, 1990, four two-inch diameter monitoring wells (designated as MW1, MW2 , MW3, and MW4 on the attached Site Plan, Figure 1) were installed at the site. The monitoring wells were drilled and completed to total depths ranging from 69 to 74 feet below grade. Ground water was encountered at depths ranging from 58. 5 to 59. 5 feet beneath ground surface during drilling. Well elevations were surveyed by a licensed land surveyor to Mean Sea Level (MSL) and to a vertical accuracy of 0. 01 feet. The wells were developed on October 18, 1990, and were initially sampled on October 26, 1990 .