ARCHIVED REPORTS XR0000750 - Laserfiche WebLink

Home Browse Search

4 . 07 March 2003 AGE-NC Project No. 95-0106 Page 2 0£4 Department' of Health Services-certified analytical laboratory for analysis..The samples were . t' analyzed'for: Total 'Petroleum hydrocarbons quantified as gasoline (TPH-g) in accordance with ' EPA Method 8015-Modified, and •. Benzene,toluene,ethylbenzene,and,total xylenes(BTE&X)and methyl tertiary butyl ether (MTBE) in'accordance with EPA Method 8021. , 1 3.0. ' FINDINGS ' Ground water.elevation and flow direction were'inferred-from field data; hydrocarbon-impact to. ground water was quantified by laboratory analysis of the ground,water samples. 3.1. . .GROUND WATER ELEVATION AND FLOW DIRECTION ' • The relative ground water elevation ranged from 33.24 feet.(MW-6 lower) to 34.07 feet (MW-2); increasing an average of 1:25 feet since the September 2002 monitoring. event. The water table . appears as a northerly plunging ridge; the east limb of the ridge flows toward the northeast at a gradient of approximately 0.003 f11f1, and the west limb flows toward the north-northwest at a gradient of approximately 0.005,f11fL Ground water elevation data is presented in Table 1 while the `.- contoured ground_water elevation data is shown on Figure 3. 3.2. ANALYTICAL RESULTS OF.GROUND WATER SAMPLES Petroleum hydrocarbons.were detected in the ground water samples collected from monitoring wells MW-1 and MW-4. TPH-g was detected-in both wells at concentrations of 150 micrograms per liter ' (µg/1) and.3,000 µg/l, respectively.'Benzene was also detected at 49 µg11 and 80 µg/l in samples MW=1,'and-MW-4, respectively. Other'concentrations of volatile'aromatic corripotinds detected in samples'MW-1 and MW4 include 16 µg/1 and 13 µg/1 of toluene, 3.2 µg/1 and 230 .µg/1.6f ' .ethylbenzene'an'd 8.5 µg/l.and 81 µg/l of xylenes, respectively. .NeitherTPH' g nor BTE&X compounds were detected in the ground water samples from monitoring ' wells MW-2,'MW-3;•MW-5, MW-6 (upper), MW-•6 (lower) and'MW-7. MTBE'was not-detected in any of the ground water•samples. Analytical results of groundwater samples are summarized on Tabid 2. The laboratory report (MAI Lab IDs.02l2367-001 through • 0209391-008), QA/QC and chain-of-custody are incltided'in Appendix C. Advanced GeoEnvkonmental,Inc.