ARCHIVED REPORTS XR0002691 - Laserfiche WebLink

Home Browse Search

1 3 r 1 r`J - f .' '3'` -. •'S,• � r -.t v ^~ 3. s �, ,�� Y �,.: y y y J 1 N, F'•µ 1$August 1997 Pioject No':.95 01.14. Page 2 6f'4 and volatile halocarbons (chlorinated hydrocarbons) in accordaricewlth EPA methods-503`0/9015m;. b02.and"601`/8010,'re'spectivel y: 3.0: .FIN-DINGS at `' �r j R 3.1. `GROUND'WATER GRADIENT AND DIRECTION'- The IRECTION -The average:.relative ground wateir'elevation at'the'site mcreased•'approximately 4 2'feet since the Decerriber. 1996,sarlpling event..Relative,ground water elevations are'summarized in'Table' 1'' Relative Ground Wafer Elevation. During the June 1997 samMing, the depth to ground water at.the site rangedfrolrl 27.23 to 27.98 feet below fops of the well�casings. Tlle'scree'ne' d,�intervals for wells MW-1-ard I�,1W-2 lie bet,"eeii-34 and 54 feet bsg,"and4he screened interval's for wells MW-3R, MW-4-`and MW-5;•Iie between 30 and 50 feet bsg, thus,ground water'is above the tops of.the screened intervaLin all.five,nionitoring wells. r Th&gr ound water elevation data-can be interpreted several ways;but appearsto us t6indicaze ground' M water flow generally toward monitoring well MW-1 from'the northern and eastern portions of the property. Ground water appears'.to be,flowing southwestward from the,area of NINV L'The ground' Y.' water gradient appears to^be steepest from MW=2 flowing northeastward (--0.036 ft/ft);.and less steep flowing southeastward from the area-between'MW�5 'aiid MW-4 towaid',M1W- . 1 ,,{�0.OU7 ft/ft). A giadient toward the, southwest from MW-1 cannot be calculated. :PETROLEUM HYDROCARBON-IMPACTED GROUND WATER ' During the June 1997 sampling, TPH=ss was-detected in monitoring-wells-MW-2 and MW-3R,at concentrations of'470 parts per'billion.(ppb,'reported as micrograms per iter) and 2;800 Pp respectively. TPH-ss was not detected.in the samples.collected.from MW- ,-.MW-4 or-'A4I .�-5 during this'sampling event: • 4 BTE&X compounds.were detected only in the•water sample collected_from monitoring v"611.'MW 3 "Which contained 5.9 ppb berizerie;4':l ppb toluene;,9.1 ppb.ethylbenzene, and 4A,ppb xylenes. " M as also quantif ed at 37 pptiby:EPA Method 81020,'however laboratory.comments indicted. ,that the MTBE would not likely.-b6 detected by EPA method 8260: MTBE was not detected in any other:of the ground-water samples 'collected. Analytical -iesults•of• ground water-.samples are w summarized'in Table'2.,-Analytical Resiulls.ofStoddard and-BTE&XAnalyses. The laboratory:report U (MAL Laboratory ID'numbers 77096,-ttirb6gh,77100) 'chain-of_custody'and QA/QC' ieport,acre Advanced GeoEnvironmental,.Inc. ,;;