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KEI-P89-1104 .R7 December 101 1990 Page 6 unclear if the annulus between the six and ten--inch diameter casings was backfilled or open. A second phone call was placed to Diane Henson on April 23 , 1990, and it was determined that only grouting of the inside of the six-inch casing would not necessarily provide an adequate seal to protect the ground water, and we were instructed not to destroy the water well at this time. The water well was provided with a temporary surface seal on April 23 , 1990, prior to leaving the site, by driving in a circular wood plug, pouring one sack of bentonite powder gel over the wood plug and vicinity, and placing cement over the bentonite gel. KEI contacted Purviance Drillers, Inc. of Linden, California, for a proposal to properly abandon the dual cased water well. It was initially proposed to jet out any materials within the annulus spacing between the two well casings, split the six-inch diameter casing with a down-the-hole perforator tool, and to place Baroid Aquagrout Benseal within the annulus and within the six-inch 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 determine 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 joints, 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 level at 54. 5 feet; 6 . At a depth of 125 feet, a well size reduction was indicated • when the camera could not pass; and, 7 . Total well depth measured at 133 feet.