WORK PLANS - Laserfiche WebLink

Home Browse Search

Site Background Information: Stallworth Auto Sales Page 3 of 9 • Fuel oxygenates were not detected in the soil samples analyzed. • After the installation and development of the five ground water monitoring wells on-site, each well was sampled. The ground water samples were analyzed for the suite of five fuel additives and, with the exception of MW- 1B, for TPH-g, TPH-d and BTEX. • TPH-g was detected in the ground water samples collected from monitoring wells MW- IA, MW-2 and MW-3 at a maximum concentration of 380,000 µg/l (MW4A). TPH-d was detected in the ground water sample collected from monitoring well MW- lA at a concentration of 13 ,000 µg/1. The highest concentration of hydrocarbon-impacted ground water resides in the area of the former USTs. • BTEX compounds were detected in the water samples analyzed from MW4A, MW-2 and MW-4 at concentrations as high as 3 ,000 µg/1, 100,000 µg/1, 6,500 µg/1 and 32,000 µg/1, respectively. Fuel oxygenates were not detected in the ground water samples analyzed. On 20 November 2001 , one soil boring (CPT-1) was advanced on-site utilizing CPT technology to model the geological and hydrogeologic framework and to assess potential dissolved petroleum-migration pathways beneath the site. Lithologic data was collected from the boring. A twin boring was then advanced to collect grab ground water samples from selected depths. • Ground water samples were collected from CPT- 1 at the following intervals : 71 feet to 74 l feet bsg, 104 feet to 106 feet bsg, 126 feet to 129 feet bsg and 145 feet to 148 feet bsg. • TPH-g was detected in all four water samples collected at concentrations of 16,000 micrograms per liter (µg/1), 500 gg/1, 460 µg/1 and 140,000 µg/1, respectively. TPH-d was detected in three of the water samples collected at concentrations as high as 40,000 µg/1. ' i • BTEX compounds were detected in all the water samples collected at concentrations as high as 560 µg/1 benzene, 12,000 µg/1 toluene, 3 ,000 µg/1 ethylbenzene and 15,000 µg/1 total xylenes . • DIPE was detected in the water sample collected from 126- 129 feet bsg at a concentration of 1 .4 µg/1. EDB was detected in the sample collected from 145- 148 feet bsg, at a concentration of 86 µg/1. 1 ,2-DCA was detected in the water samples collected from 71 -74 feet bsg, 126429 feet bsg and 145- 148 feet bsg at concentrations of 1 .3 µg/1, 1 . 8 gg/l and 11 µg/1, respectively. On 24 June 2002, two ground water monitoring wells (MW-5 and MW-6) were installed at the site. MW-5 and MW-6 are screened from 20 feet to 40 feet bsg. ' i • No soil samples were collected from boring MW-6 . A total of 3 soil samples collected from well boring MW-5 were analyzed for TPH-g, TPH-d, BTEX, the suite of five fuel additives, Advanced GeoEnvironmental, Inc. i