ARCHIVED REPORTS_XR0004072 - Laserfiche WebLink

Home Browse Search

PoMho Property Corrective Action Plan Page: 7 ' It should be noted that Bioscreen4 modeling predicts BTEX plume stability at 120 ifeet from the point of release in 15 years with a residual groundwater ' contamination in the source area x£7700 ug/l. total BTEX. MTBE plume stability is not predicted within at 200 feet from the point of release in 30 years with a residual groundwater contamination in the source area of 625 ug/l. MTBE. 1 4.2 Source Removal / Natural Attenuation This scenario predicts the effects of the excavation and above ground aeration of ' the excavated contaminated soil followed by one year of groundwater monitoring to confirm the plume stability and reduction. Plume stability is predicted for BTEX groundwater contamination in 15 years at 120 feet from the source. A residual contamination is not predicted for the source area. MTBE plume stability is predicted at 270 feet from the point of release in 30 years. A residual MTBE contamination is not predicted for the source area 4.3 Aerobic Bioremediation ' This scenario predicts the effect of an in-situ enhanced oxidation through the injection of an oxygen release compound (ORC) through small diameter direct push drill rods. The injection of the ORC would have the effect of increasing the ' oxygen content in the source area and increasing the biological activity of naturally occurring aerobic bacteria. The Bioscreen4 modeling reflects that • increases first order reaction rate caused by the increased aerobic biological activity. The injection of the ORC would be followed by one year of groundwater monitoring to confirm increased*iw biological activity, plume stability, and ' plume reduction. Plume stability is predicted for BTEX groundwater contamination at 40 feet from ' the source in 3 years. A residual BTEX groundwater contamination of 4978 ug/l. is predicted for the source area. MTBE plume stability is predicted at 160 feet from the point of release in 21 years. A residual MTBE contamination of 625 ug/1 ' is predicted for the source area 4.4 Source Removal/ Aerobic Bioremediation ' This scenario predicts the effects of the excavation and above ground aeration of the excavated contaminated soil, the emplacement of an oxygen release ' compound (ORC) at the base of the excavation, followed by one year of groundwater monitoring to confirm the plume stability and reduction. ' Plume stability is predicted for BTEX groundwater contamination at 60 feet from the source in 9 years. A residual BTEX contamination is not predicted for the source area. MTBE plume stability is predicted at 160 feet from the point of t release in 21 years. A residual MTBE contamination is not predicted for the source area.