Laserfiche WebLink
CHRONOLOGY <br /> SWENSON GOLF COURSE <br /> CITY OF STOCKTON <br /> 6803 ALEXANDRIA, STOCKTON CA 95207 <br /> 02/11/92 A 1,500-gallon regular gasoline underground storage tank (UST) State <br /> ID 31638001 was removed on February 11, 1992 at the above referenced <br /> site. The stockpile from the excavation exhibited odor and soil <br /> discoloration, but the soil beneath the tank had no odor. Groundwater <br /> was not encountered. The stockpile was placed back into the excavation <br /> with a plastic liner in between. Soil samples were collected for <br /> laboratory analyses. <br /> 02/18/92 Received analytical results of soil samples. Sample results at 9.5 feet <br /> below surface grade (bsg) was 0.52 parts per million (ppm) Xylenes. <br /> 03/18/92 Filed Unauthorized Release Report (UAR), Prop 65, and contaminated <br /> site letter. <br /> 12/31/97 The site was placed into San Joaquin County Public Health Services <br /> Environmental Health Division (PHS/EHD) Local Oversight Program <br /> (LOP). Official Notice of Responsibility was mailed to City of <br /> Stockton (COS) requiring additional work to investigate the <br /> contamination. <br /> 07/20/98 2 soil borings and 1 monitoring well were installed on site. No odor or <br /> discoloration was noted in the soil and groundwater samples taken. <br /> 11/18/98 Received Closure Summary Report dated November 18, 1998 prepared <br /> by Advanced GeoEnvironmental, Inc (AGE). Only one soil sample <br /> taken at 5 feet bsg of borehole #1 (B-1) which was advanced through the <br /> center of the tank pit evidenced contamination at 830 ppm gasoline, 0.58 <br /> Toluene, 7.1 ppm Ethylbenzene, and 58 ppm Xylenes. Benzene and <br /> oxygenates were non-detected. Analytical results of all other soil <br /> samples from both boreholes and monitoring well were non-detected in <br /> gasoline, BTEX, and oxygenates. Analytical results of the MW water <br /> samples taken on 07/20/98 and October 16, 1998 were non-detected in <br /> gasoline, BTEX, and oxygenates. Using 400 ppm as the "average" <br /> concentration of gasoline in a plume of"average" radius of 5 feet, AGE <br /> calculated approximately 1.9 gallons of total gasoline mass remains in <br /> the ground. <br /> 01/13/99 Prepared Chronology and Case Closure Summary. <br />