ARCHIVED REPORTS XR0001535 - Laserfiche WebLink

Home Browse Search

t . 10 September 2004 AGE-NC Project No 03-1100 Page 2of10 2 2 GROUND WATER DEPTH AND FLOW DIRECTION Ground water is currently encountered at a depth of approximately 40 feet bsg in on-site ground water monitoring wells, the flow direction is generally towards the south to southeast Historically, the depths to ground water measured in the on-site monitoring wells and soil borings have ranged from approximately 39 to 46 feet bsg, relative ground water elevation maps for the site have been included in previous quarterly reports prepared by Wright Environmental Services, Incorporated (WES) and AGE 23 UST REMOVAL Two, 10,000-gallon capacity USTs and a dispenser island were formerly present at the subject site The dispenser island and USTs were located in the central portion of the site On 27 October 1992 the USTs, associated product piping and dispenser island were removed from the site by Falcon Energy Associated (FEA) Three soil samples were collected from beneath each of the USTs and analyzed for total petroleum hydrocarbons quantified as gasoline(TPH-g)and total lead TPH-g was detected in analyzed soil samples at concentrations as high as 4,400 milligrams per kilogram (mg/kg) 24 PREVIOUS SITE INVESTIGATIONS On 17 August 1994 FEA advanced one soil boring(B 1) in the center of the former UST excavation to a total depth of 60 feet bsg Soil samples collected from 30 and 40 feet bsg contained detectable concentrations of TPH-g, toluene, ethylbenzene and xylenes A grab ground water sample was collected from boring B 1 TPH-g and benzene,toluene,ethylbenzene and total xylenes(BTEX)were detected at maximum concentrations of 76,000 micrograms per liter(µg/1)TPH-g, 38 µg/1 benzene, 310 µg/1 toluene, 4 8 µg/1 ethylbenzene and 6,800 µg11 total xylenes On 05 and 06 January 1999,Ramage Environmental(RE) conducted an additional investigation of the subject property Five soil borings were advanced for the collection and analysis of soil and ground water samples Three of the borings were completed as ground water monitoring wells screened from 30 to 50 feet bsg Petroleum hydrocarbons were detected in soil samples collected during the January 1999 investigation The highest concentrations were encountered in samples collected from beneath the UST excavation On 25 April 2000, one Cone Penetration Test(CPT)boring was advanced at the subject property to determine the site stratigraphy and the vertical extent of impacted soil and ground water Soil Advanced Geo Ennronmental,Inc