ARCHIVED REPORTS_XR0004480 - Laserfiche WebLink

Home Browse Search

2004 3' Quarter Groundwater Report Frontier Transportation January 10,2005 i Page 5 j m, ,ky in Dot fc 2004 groundwater sampling also identified dissolved MTBE in MW-9 at 1�4g/L, andin W��g e 17 at 3 1 µg/L The grab sample for MW-13 identified dissolved MTBE at 39 µg/L. No "` )" dissolved MTBE was detected in the deeper momtonng wells. The elevated dissolved MTBE WC ' concentrations are limited to the shallow monitoring wells only See Figure 13 for the recent shallow well MTBE lsoconcentration Map i t k � Detectable concentrations of dissolved ETBE and TAME were identified exclusively in �A&� monitoringwell MW-3R for the groundwater samples collected in September 2004 ETBE was � P P �S found at 3 Og/L and T was identified at 3 0µg/L. No detectable ETBE or TAME was ar ��- ' identified in the other W,�Is. Groundwater samples collected from the remaining aft-H$4 8krt � monitoring wells identified no detectable concentrations of TBA, DIPE, 1,2-DCA or EDB using EPA method 8260 'iaril js"4�L oS 5.0) WASTE MANAGEMENT �rv � y` sow Va,�,,,1`', �g. ' Any free product, purged groundwater, and decontamination water generated from the site during sampling activities will be stored in sealed 55-gallon drums for a period not to exceed �. 90 days Stored wastes will be profiled for hazardous constituents and characterized as Non- Hazardous, California Hazardous, or RCRA Hazardous, as appropriate Any transportation;of waste will be under appropriate manifest ' ' 6.0 CONCLUSIONS AND RECOMAMNDATIONS � •S Based on groundwater sample analysis results, the dissolved MTif lume appears to be u � L ' slowlyex andun to the west. No detectable to low level concentrationow CDHS rimary r P g 4 P MCLS)of dissolved TPH-g and BTEX were identified m a1�.Wmonitoring wells u1 rdedicated to the site Hg ver the identification of dissolved MTBE in MW-1, MW-3R, MW-9, •r` MW-13 and MW-1 ndica e at�ateral migration of MTBE may be occurring beneath the site ' BE][[ recommends that quarterly groundwater monitoring continue at the site until constant or decreasing dissolved MTBE concentrations are observed. Further, migration of ' MTBE indicates that the source area may need to be re-excavated to prevent additional N C migration. Groundwater samples will be analyzed for BTEX using EPA method 8020, TPS ) � T� and TPH-g using EPA method 8015m, and oxygenates using EPA method 8260 in all future 0 ' monitoring episodes as directed by the PHS/EHD Should dissolved MTBE concentrations d rf all) continue to be above EPA primary MCLS beneath the site,then groundwater remediation/treatment may be warranted `YW Iii �+it" 'd G� 1