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7. 1 S '.7. S j �5_ ' !- .f. / hl ll_y „i4 �' Y r•'f♦ ^} F �i` 1 � !ir l9 S1 c < "'� ;�• ' � � � a � 1 ° syr ��, r , ' t 1� 20 August'2001 `^ AGE-NC Project No. 95 01I4.: ' a Page-6 6f-9.. ;h s 3.0.- ' V FINDINGS y Ground'water'flow direction and gradient .were calculated from the f eld data. The current distribution'.of,-adsorbed and dissolved .petroleum hydrocarbons ;and-.dissolved' chlorinated' r hydrocarbons was assessed from laboratory analytical results of the s6il,and ground water samples' - S. s I '1, ., +• ' • - Y } ' !1 3.1. GROUND WATER..GRADIENT AND DIRECTION The ground water elevations were calculated-by subtracting the measured depth rto ground water from ` „ the surveyed'casing elevations (Table'l). Ground water elevations were plotted and contoured'on a scaled site map. During the April 2001 ground water-monitoring'event, the depth to ground water at the site'ranged -from 20.85 to 2L85' feet, elow tops of the well casings.. , The ground water gradient and flow direction were.variable"across the site during the April 2001• , monitoring event: Grourid'water flow direction varied from.northwest to northeast; the greatest gradient was approximately'0.005 generally toward the northwest-from well MW-1, toward'well MW-5.. Ground water-elevation data are summarized in-Table, 1'. The contoured relative ground. water elevation for:the.April 200 1-gro und.water monitoriirg evert is depicted in Figure 3: 1 Wells MW-1 and MW-2 are screened betweeri 34-and 54 feet bsg;wells MW-3R;MW-4 and MW-5 are screened between°30'and 50 feet_bsg; wells'MW-6 and MW-7 are screened between 25 and 45 feet bsg.,Ground water is'more than 1 f feet above the,tops;of the screened intervals of wells MWI' ' and MW-2; 7'feet above the tops.of the screened intervals of wells MW-3R, MW-4•and MW-5,and 2' feet above the tops,of the, screened intervals of wells MW-6_and MW-7. Therefore', samples.. collected from these`wells may not Ibe representative of ground watei'condiiions at or near the top _ ' of the saturated soil zone•or capillaryzone, where the eatest h drocarbon im act to. ` ound water, " _ gr Y P ....is often encountered. 3.2. PETROLE_ UM.HYDROCARBON-EgP.ACTED.GROUND WATER-' , the April.2001 monitoring event .TPH-ss was detected in sam les from momtorin wells Durrng . g P g MW-2 and MW-3:at concentrations of 370 micrograms per-liter,(j_ig/i),and-1,100.Azel, respectively. TPH-ss was not'reported in the sarriplcs collected from wells MW-1, MW-4, MW-5, MW-6 or MW-7 during this sampling event. Advanced CeoEnvironmenial,ine.