Laserfiche WebLink
J <br /> 25 September 1995 <br /> i AGE-NC Protect No 95-0137 <br /> ' Page 4 of 6 <br /> Portland cement Borings B-10, B-12, B-13 were each backfilled from total depth to the surface <br /> with Portland cement <br /> ' 3 5 GRAB GROUND WATER SAMPLE COLLECTION <br /> ' Upon completion of drilling for B13, a grab water sample was collected from the boring at an <br /> approximate depth of 20 feet The water sample was collected from the boring using a new, clean, <br /> disposable Teflon bailer and by transferring the collected water into preserved 40-m1 EPA vials and <br /> 1-liter amber bottles The sample was stored on ice and relinquished to Pan Ag Laboratories for <br /> analysis The sample was analyzed for TPH-g, TPH-d and BTE&X in accordance with EPA methods <br /> 5030/8015 and 602, respectively <br /> 4.0. FINDINGS <br /> ' 4 1 GROUND WATER GRADIENT AND DIRECTION <br /> In May 1995, the depth to ground water at the site ranged from 18 79 to 19 60 feet The data <br /> indicates an average increase in ground water elevation of approximately one foot since February of <br /> 1995 Based upon data collected on 24 May 1995, the ground water gradient was calculated to be <br /> 0 0008 fl/ft, directed N 19° W(Figure 3), which is consistent with regional ground water flow The <br /> greatest increase of ground water elevation was observed in the southern portion of the site Ground <br /> 1 water elevation data is summarized on Table 1 <br /> ' 4 2 PETROLEUM HYDROCARBON-PvfPACTED GROUND WATER <br /> TPH-g was detected in monitoring wells MW-1, MW-2 and MW-3 at concentrations of 510, 7,000 <br /> and 350 ppb, respectively, and samples from these three wells contained TPH-d at concentrations of <br /> 790, 8,900 and 6,700 ppb, respectively BTE&X were detected in samples from each well at <br /> concentrations up to 1,100 ppb(xylenes, MW-2) The analytical results of ground water samples are <br /> ' summarized in Table 2 The laboratory report and chain-of-custody are included in Appendix C <br /> ' 43 SOIL PROFILE <br /> Light brown, clayey, fine-grained sands and gray, silty, fine-grained sands were encountered in MW-5 <br /> (B9) and MW-4(B l 1) Borings BIO and B12 contained gray, silty, fine-grained sands, throughout <br /> i the profile Boring B 13 was comprised of mostly brown silty, fine-grained sands and a brown, clayey <br /> [ coarse-grained sand at a depth of 20 feet Saturated conditions were encountered in all bonngs at <br />