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05 February 2015 <br /> AGE Project No. 14-3298 <br /> Page 2 of 5 <br /> Several investigations, including installation and sampling of monitoring wells have been <br /> historically conducted at the site. Analytical results from these investigations indicated <br /> that minimal hydrocarbon impact was present in soil surrounding the former dispenser <br /> islands and at the tank excavation base. However, groundwater impact was not present <br /> in site monitoring wells. <br /> Based on historical investigations, AGE performed a soil-vapor investigation to evaluate <br /> the potential for soil-vapor intrusion at the site in the former dispenser and underground <br /> storage tank areas, in the location of the former site building, and in the northeast <br /> corner of the site, between the former fuel system and the adjacent property to the east. <br /> BORING ADVANCEMENT <br /> On 22 January 2015, AGE advanced six soil borings (V-1 through V-6) at the subject <br /> property. Soil borings V-1 and V-2 were advanced in the location of the former <br /> dispenser islands for collection of soil-vapor samples at five and ten feet bsg; boring V-3 <br /> was advanced in the northeast corner of the property, between the former dispenser <br /> islands and the adjacent property to the east for collection of soil-vapor samples at five <br /> and ten feet bsg; boring V-4 was advanced in the location of the former site building for <br /> collection of soil-vapor samples at five and ten feet bsg; and borings V-5 and V-6 were <br /> advanced in the location of the former UST area for collection of a soil-vapor sample at <br /> five feet bsg in V-5 and at ten feet bsg in V-6. Soil borings V-1 through V-4 were <br /> advanced to ten feet bsg; boring V-5 was advanced to seven feet bsg; and boring V-6 <br /> was advanced to ten feet bsg. Initially, all borings were to be advanced to ten feet bsg <br /> for collection of soil-vapor samples at five and ten feet bsg. However, refusal was <br /> encountered in boring V-5 at seven feet bsg. Boring V-5 was abandoned and boring V-6 <br /> was advanced approximately 3 feet north of V-5 for collection of a soil-vapor sample at <br /> ten feet bsg. Soil boring locations are illustrated in Figure 1. <br /> Soil borings were advanced utilizing a van-mounted, GeoProbe 5400 direct-push <br /> probing unit equipped with 1.25-inch diameter probing rods. The direct-push probing <br /> unit advances soil borings using a hydraulic hammer to drive sampling tools to specified <br /> depths. <br /> SOIL-VAPOR SAMPLING <br /> Soil-vapor samples were collected from borings V-1 through V-5 at five feet bsg using a <br /> Geoprobe soil-vapor sampling assembly. An expendable vapor point was placed into a <br /> point holder at the bottom of an assembly of 1.25-inch diameter hollow drive rods. The <br /> assembly was then advanced to five feet bsg and retracted approximately six inches in <br /> order to disengage the expendable point and expose a column of strata from which soil- <br /> vapor was extracted. Single use, '/4-inch diameter disposable polyethylene post run <br /> Advanced GeoEnviron mental,Inc. <br />