ARCHIVED REPORTS XR0008543 - Laserfiche WebLink

Home Browse Search

. Site Background Information Quick N Save #1 Page 2 of 3 1 UNDERGROUND STORAGE TANK REMOVAL ' On 21 October 1999, three USTs and associated piping and dispenser islands were removed from the site by Stockton Service Station Equipment Company (SSSEC) of Stockton, California ' Approximately 150 cubic yards of hydrocarbon-impacted soil were removed and stockpiled during excavation of the USTs Nine samples were collected beneath the USTs, six samples were collected beneath the dispenser area and two laboratory-compo sited soil samples were collected from the excavated stockpiled soil Methyl tertiary butyl ether(MTBE),tertiarybutanol(TBA),tertiary-amyl methyl ether(TAME)were ' detected in each of the soil samples collected from the site Total petroleum hydrocarbons quantified as gasoline(TPH-g)were detected at concentrations as high as 3,849 mg/kg beneath the western end of the center UST location Volatile aromatics including benzene,toluene,ethylbenzene and xylenes ' (BTEX) were detected at concentrations as high as 29 mg/kg from the same sample location SOIL EXCAVATION On 20 April 2000, approximately 175 cubic yards of petroleum hydrocarbon-impacted soil were excavated from the former UST area Excavation was performed by SSSEC 1 The highest concentrations of petroleum hydrocarbons,TPH-g and fuel additives were detected near the eastern end of the center UST(sample EN-16') Fuel oxygenating compounds,including MTBE, TBA and TAME,were detected in each of the soil samples collected from the site at concentrations 1 as high as 11,000 mg/kg TPH-g was detected at concentrations up to 12,000 mg/kg beneath the western end of the center UST location BTEX was detected at concentrations up to 1,800 mg/kg `II (total xylenes) PREVIOUS SITE ASSESSMENT ' On 05 and 06 August 2003, four soil probe borings (B 1 through B4)were advanced to a total depth of 50 feet bsg utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1 25- inch diameter probing rods Two borings were advanced east and west, respectively, of the former UST excavation, the third boring was advanced north of the former UST excavation, the fourth ' boring was advanced east of the dispenser islands TPH-g,MTBE,and BTEX compounds were detected in soil samples analyzed from all four borings TPH-g was detected in soil samples at maximum concentrations of 21,000 mg/kg in boring 131 at 35 feet bsg MTBE was detected in soil samples at maximum concentrations of 5 6mg/kg(B4-35') BTEX compounds were detected at maximum concentrations of 27mg/kg, 600mg/kg, 270mg/kg, Advanced GeoEnvironxnental,Inc