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• 04 August 2000 AGE-NC Pi oject No 98-0521 Page 10 of 11 - I- _ 44 GROUND WATER ELEVATION, FLOW DIRECTION AND GRADIENT On the sampling date, the depth to gi ound Nvatet_at the site i anged ft om 7 45 to 7 91 feet below the tops of the well casings The gr ound water elevations at the site i anged fi om-7 13 feet to -7 53 feet mean sea level (nnsl) The ground water flow dr,ection and gradient we,e calculated fi om the well elevation data The gi ound water flow was_dir ected towar d the northeast The gt ound water hydr auhc gr adient was calculated to be 0 01 3 feet/feet Figur e 4 tllusti ates the contour ed gr o and water elevations as measur ed on 07 June 2000 50 SUINVINIARY AND CONCLUSIONS The following conclusions wer e dr awn fi om the ,esults of this investigation ' Gr ound water-at the site was encounter ed atapp,ommately 7 5 to 8 feet bsg The pr evading g,otirnd water flow du ectron at the site is gener ally towar d the northeast The gr ound water hydr aullc gr adient was estimated to be 0 013 feet/feet • Tr ace to loN,, concent,at,ons of pet,oleu►rr hyd,oca,bons ,vei e detected soil samples collected fi orn the capillary fi inge and satin aced zone in the former UST excavation (bor Ings B-6 and B-7) and the a,ea to the east of the exca�atron (borings B-3 and B-4) The hyd,ocarbon- impacted soil was-bunted to depths above 25 feet bsg in the forrrler excaxatron MTBE was -' only detected in at 10'to 15 feet east of the former excavation • Drssoh ed phase hyd,ocar bons,,rfcludrng TPH-g, BTE&X and oxygenates ar e pr went,n the - g�ound water Hydr ocar bons NY e encounter ed in the down-gr adient du ect ion fi om the UST to the location of monito,rng well 1v W-2 The hydrocarboci concentrations un ground ovate, deci ease eastwai d in the ar ea of soil pr obe bor rng B4 and decr ease no3-theast of the for7lter USTs in the al ea ofN�ell MVv-2 The app,oximate later al extent of the drssoh ed phase TPI i- g BI E&X and MTBE plumes are depicted on F,gu,e 5 _ Analylical data fi om the initial site assessment indicates that r emedration of sort and'or gr otmd ate, may be r equrr ed at the site Additional site assessment, well installation and sampling will be r eclurr ed to ftrll� assess the late,al e\tent of the dissolved hyd,ocatbons 5 IdiunndGtoI m11UIt MLJ1 rIiL