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' Page 18 <br /> G¢ologlcal7¢clutics W. <br /> Site Conceptual Model Report <br /> Project No 724 2 <br /> May 2,2006 <br /> r� <br /> ' A second line of evidence supporting the conclusion that the contamination in MW-208 is <br /> from the GASCO site is the contaminant trends in the deep wells on the Morita site Well <br /> ' MW-208 has shown an increasing trend of TPH-G since sampling started in March 2004 <br /> while the other wells have had little to no contamination as shown in the graph below <br /> MW-202,MW-208,MW-209&MW-210 TPH-Gvs Time <br /> 1600 <br /> r, <br /> ` r'& •• ' <br /> y <br /> ���n�i'a' <br /> 1200 t "" F cto <br /> r *x ° X s x <br /> ,� <br /> 1000 � .`cr r A , a <br /> —BMW 202 <br /> BOD r � M1" y — �rrca7�"�w _' s 3 —MW 208 <br /> H 600 " � � v � °r x "� k " 3aEs —r MW 209 <br /> —*--MW 216 <br /> 466 <br /> F �Rr ra S p <br /> b ��� _• _�,� .��Stat �'*°��i'-��.r �p� <br /> �'���� <br /> ' 200 �`v #Ac t.r <br /> X° <br /> 0 Ti's o <br /> Date <br /> ' It is noted that the data plotted for MW-202,209&210 are clumped together on the bottom of the graph <br /> The initial 380 ug/l TPH-G in well MW-202 is likely a drilling artifact (through the on site <br /> ' impacted intermediate aquifer) as the well has been non-detect since December 2003 But <br /> given the locations of wells MW-209 and MW-210 in relation to the former Morita USTs and <br /> dispenser island you would expect the above fluctuating deep aquifer gradients to "smear" <br /> the plume to the locations of these two deep wells But this isn't the case as shown in Figure <br /> 16 <br /> ' In Section 2 6 2 GTI represented the Morita groundwater TPH-G plume as shown in Figure <br /> 14 Cross Section A-A' with GW TPH-G plume But that cross section drawing does not <br /> intersect the highest TPH-G detected in well MW-208 Figure 17 Cross Section B-B' with <br /> ' GW TPH-G plume shows GTI's interpretation of a deeper plume being sourced from the <br /> GASCO site The intermediate level aquifer ranges from non-detect to low levels of TPH-G <br /> present in wells MW-1, MW-2, MW-107, MW-108 and CPT-2 @ 46' bgs This is in <br /> ' contrast to the 1580 ug/1 present in deep well MW-208 The stippling pattern in the plot <br /> shows the attenuation of the TPH-G away from MW-208 toward MW-202 as in the plan <br /> view in Figure 16 GTI did not include mass balance calculations for this portion of the <br /> ' aquifer because we believe it is from the GASCO site <br />