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• Section 10-1 astruction Details Standard Specifications Section 14 Special Page 2 of 7 80 feet. The well has been subsequently re-sampled, and results indicate PCE is no longer detectable in samples from this well. Well LVMD2--History and Description LVMD2 was drilled in 1950 using cable tool equipment. It was drilled to a total depth of 300 feet bgs. Fourteen-inch-diameter 7 gage steel casing was installed from ground surface to 126 feet, which was cemented in to approximately 80 feet. From 124 to approximately 260 feet bgs, 12-inch diameter 10 gage steel casing was installed. This well was videotaped in 1990, which indicated groundwater was at a depth of 59 feet bgs. Vertical perforations were noted from 212 feet to 252 feet. The perforations were noted to be 60 percent plugged at 215 feet bgs, and 10 percent plugged at 240 feet bgs. The borehole was open from 260 feet to 276 feet. Additionally, a video log indicated that possible holes in the casing occurred at a depth of 136 feet bgs. This well was sampled in December 1990 or January 1991, and the sample contained 47 µg/1 PCE, 8 . 5 µg/1 TCE, and 5. 8 pg/1 cis-1, 2 DCE. Later in 1991, the well was noted to have caved to 118 feet bgs. The well was videotaped again in February 1992 in an attempt to determine the cause of the caving. The well depth had decreased to 100 feet bgs, but the cause and character of the caving could not be determined. The caving may be related to the holes noticed in the casing at a depth of 136 feet, or to the reduction in the casing diameter at 128 feet. Well LVMD4--History and Description LVMD4 was installed in 1980 using cable tool equipment. The well was drilled to a depth of approximately 205 feet. It was completed with 14-inch diameter 14 gage steel casing from 0 to 70 bgs, with a sanitary seal to 70 feet bgs. From 0 to 130 feet, 10- inch-diameter 10 gage steel casing was installed. The water well drillers report states that the depth of the completed well is 195 feet. No casing perforated zones were noted. This well is not thought to contain PCE and is being destroyed because of the occurrence of iron and manganese in the water. Well LVMD6--History and Description LVMD6 was installed in 1958 using cable tool equipment. This well was drilled to a total depth of 266 feet and was constructed of 14-inch diameter 7 gage steel casing, with vertical perforations from 210 to 262 feet. A sanitary seal was placed from 0 to 40 feet. In 1984 , the well was lined with 8-inch diameter PVC casing to mitigate a sand production problem. The invoice from this work indicates that the PVC casing is solid from 0 to 162 feet bgs and from 242 to 262 feet bgs. This well was videotaped in 1990. It was noted that vertical slots were present from 85 to 115 feet bgs and from 145 to 160 feet bgs. Horizontal perforations were noted 6691\SPECS VSECCION.14