ARCHIVED REPORTS XR0008058 - Laserfiche WebLink

Home Browse Search

June 13, 1997 Page 4 On April 15, 1997, Mr Eric Mar, Production Superintendent of CWSC, was interviewed to determine whether there are any actively used municipal wells within a 1/2-mile radius of the subject site According to Mr Mar, no active municipal wells are located within a 112-mile of the site One municipal well was located at the corner of Anderson Street and Center Street (approximately 0 3 miles north-northwest of the site), but was confirmed by Mr Eric Mar to be inactive for at least 6 years PREVIOUS INVESTIGATIONS In April 1982, a leak was detected at the site in a section of the regular leaded gasoline product line The leaking line was subsequently repaired Two months later, the underground tanks and product lines were replaced The replaced USTs and product lines were originally installed in 1963 (Entnx, 1989) On September 1, 1989, Entrix observed the removal of four USTs (three 10,000-gallon and one 1,000-gallon waste oil) and associated product-lines, and collected soil samples from the tank and product line excavations A total of six soil samples were collected within the gasoline UST excavation, two samples collected from the waste oil tank excavation and four samples collected from points along the product line trench TPH- g and benzene concentrations reported within the gasoline UST excavation ranged from non-detect to 890 parts per million(ppm), and 0 003 ppm to 0 93 ppm, respectively TPH-g and benzene were also reported in the product line trenches at concentrations ranging from non-detect to 60 ppm, and non-detect to 12 ppm, respectively TPH-d and Oil and Grease were reported within the waste oil UST excavation at concentrations ranging from 86 ppm to 200 ppm, and 690 to 1,800 ppm, respectively Entrix concluded that soil was impacted at the site and that the highest concentrations of hydrocarbons occurred at the location of the waste oil tank excavation and the eastern side of the gasoline UST excavation (Entrix, 1989) Included as Attachment C is a copy of a Underground Storage Tank (UST) Unauthorized Release/Contamination Site Report On April 20, 1990, Groundwater Technology, Inc (GTI) reported the removal of hydrocarbon impacted soil from the former gasoline and waste oil UST excavations for remedial treatment Approximately 600 cubic yards of soil were removed from the gasoline UST pit (including the pump island located north of the USTs) and the waste oil UST pit The approximate depth of excavation was between 8 to 20 feet bgs for the gasoline UST pit and 10 feet bgs for the waste oil UST pit A total of I 1 soil samples were collected from the excavations (3 samples on January 29, 1990 and 8 samples on March 5, 1990) TPH-g and benzene concentrations were reported highest at 20 feet legs (approximately 10 feet north of the former gasoline UST location) at 3,400 ppm and 79 ppm, respectively TPH-g and benzene were reported non-detect in the waste oil . UST pit with the exception of a detection of 0 01 ppm of benzene During excavation on January 29, 1990, two additional USTs were encountered to the west of the previous 9201036A/CLOSURE DOC