ARCHIVED REPORTS XR0000992 - Laserfiche WebLink

Home Browse Search

�- sampler, vertically to depths of 60 feet bsg. Grab ground water samples were collected from each probe boring using a Geoprobe hydropunch w' sampling assembly. The probe rods were advanced to approximately 60 feet bsg. TPH-g was detected in the water samples collected from B8 and B9 at concentrations of 71 micrograms per liter (µg11) and 88 µg11, respectively. TPH-d was detected in the water sample collected from B9 at a concentration of 140 µg/1. Ethylbenzene and total xylenes were detected in the sample from B8 at concentrations of 1.2 µg11 and 1.3 µg/1,respectively. Toluene, ethylbenzene ` and total xylenes were detected in the water sample collected from boring B9 at concentrations of 0.62µg/l,0.72 Vg/1 and 4.3 µg/l,respectively.No other analytes were detected at or above laboratory reporting limits in the grab ground water samples analyzed. ADDITIONAL SUBSURFACE INVESTIGATIONS In October 2002,four 8.25-inch sail borings were advanced at the site,to be completed at monitoring wells MW-7 through MW-10. Soil samples were collected from monitoring well pilot borings at five-foot intervals, beginning at 5 feet bsg. +- Borings MW7 through MW 10 were completed as ground water monitoring wells to further assess the downgradient lateral and vertical extent of impacted soil and ground water.A total of eight soil samples were collected and analyzed for TPH-g, BTEX, EDB, 1,2-DCA and the suite of five fuel additives,including MTBE.No analytes were detected at or above laboratory reporting limits in the soil sample analysis. In March 2004,two 8.25-inch soil borings were advanced at the site,to be completed at monitoring wells MW-11 and MW-12. Soil samples were collected from monitoring well pilot borings at five-foot intervals, beginning at 15 feet bsg. Borings MW 11 and MW 12 were completed as ground water monitoring wells to further assess the downgradient lateral extent of impacted ground water. A total of four soil samples were collected �. and analyzed for TPH-g and BTEX.No analytes were detected at or above laboratory reporting limits in the soil sample analysis. SITE STRATIGRAPHY A mottled,pale brown and red-brown,stiff,clayey silt/silty clay was encountered from surface grade to depths of approximately 5 feet bsg in each boring.A pale to dark gray-green,silty,medium dense, ... poorly sorted fine sand was generally encountered from 5 feet to 10 feet bsg. A pale brown to pale gray, stiff, silty clay was encountered from 10 feet to 20 feet bsg. A pale brown, medium dense, poorly sorted, silty fine sand was generally encountered at depths between 20 feet and 25 feet bsg. +r A dark brown, very stiff, silty clay was encountered at depths greater than 25 feet bsg. Advanced GeoEnvironmental,Inc. r-