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On June 26 , 1995, we returned to the site and performed another hydropunch test 3 feet south of the original HP-2 site. This ' well was tested by first performing a CPT boring to 65 feet bgs and then placing a hydropunch into the borings and opening it between 55 and 60 feet, where the CPT log indicated the first groundwater existed. A water sample was obtained and delivered ' to the analytical laboratory, as with the sample from HP-1. The three borings were grouted with hydrated neat cement from the tbottom to the surface. FINDINGS ' The groundwater flow is to the East northeast at a gradient of 0. 0018 Ft/Ft. The groundwater level has fallen about 1 . 2 feet since the last reading. Figure 1 shows the water table elevations. ' The aquifer is confined in the area around borings BM-9 , HP-1 and 2. The aquifer becomes unconfined under the Darpetro Station. ' This was proven from the dry clay sample obtained from boring HP- 2 which came from a zone between 45 to 50 feet, even though the potentiometric surface was measured at 44 feet below the surface in the wells on the site. See Figure 3 in our report of October 10, 1995 , which is a site cross-section. The groundwater contamination is reported in Table I . Figure 2 shows the TPH contamination levels from the sampling of June 19 , 1995 for wells BM-4 ,5,6 , 7 and 9 and the contamination found in wells BM-8, 10 and 11 from the quarterly monitoring of April 25 , ' 1995. Since the purpose of these two Hydropunchs was to prove the existence of another plume entering this site, we sampled the t closest wells for contamination at the same time the hydropunch samples were obtained. ' On Figure 2 , we have drawn in the approximate 10 mg/L contour line showing the position of the two plumes at that level . The encroaching plume is labeled "Other Plume" . It appears the two plumes commingle somewhere between wells BM--4 and BM-7 and the ' contamination in wells BM-6 and 10 could be entirely from the "other plume" . ' The hydraulic gradient has been to the northeast. A gasoline plume will migrate in the direction of the hydraulic gradient. The TPH concentrations between BM-9 , HP-2, BM--7 and BM-4 do not 1 conform to the gradient direction. Those concentrations are 13 . 5, 12 .0 , 8.89 , and 14 . 2 respectively. The presence of a higher concentration of contamination up gradient from our source area can only be explained by assuming another plume source. The fact that soil samples from BM-3 ,6 ,and 7 were basically free of contamination, as well as the soil sample at 50 feet in HP-2 , ' Page 2 1