Laserfiche WebLink
t <br /> Mr. Michael Collins <br /> Page 3 <br /> August 19, 1993 <br /> SF031604.P3 <br /> CONCEPTUAL REMEDIATION PLAN <br /> Del Monte is planning to conduct remediation activities in the gasoline constituent source <br /> area. As presented in the RI/FS report, the source of petroleum hydrocarbon <br /> contamination is located in a small area within approximately 30 feet of the water table. <br /> As recommended in the RI/FS report, Det Monte is planning to use - a ;of gk <br /> alWl vapor o`� (AS/SVE)"to remediate the petroleum hydrocarbon <br /> source area and thereby significantly reduce further dissolution of petroleum hydrocarbons <br /> into groundwater. <br /> Overview of AS/SVE Technology <br /> Air sparging is a method of introducing air, and thus oxygen, into the subsurface. Air <br /> blowers inject air into wells which are screened below the water table. The air moves <br /> outward and upward through the groundwater and into the unsaturated soil where it is <br /> captured by vapor extraction wells. <br /> ASIS VE is a technology that has successfully remediated volatile organic compounds <br /> (VOCs) in unsaturated and saturated zones. In addition, air sparging is effective at <br /> remediating the capillary zone, which is located between the saturated and unsaturated <br /> zones and is often the most difficult zone to remediate with technologies such as <br /> groundwater extraction or vapor extraction. Remediation by AS/SVE occurs by the <br /> following two mechanisms: <br /> • Air bubbles that come into contact with dissolved and adsorbed VOCs, such <br /> as benzene, volatilize the VOCs into the air bubbles. The sparged air <br /> continues to volatilize VOCs as it moves upward through the capillary and <br /> unsaturated zones where it is captured by a vapor extraction system and <br /> removed from the subsurface. <br /> • The oxygen introduced by the air bubbles maintains a high dissolved-oxygen <br /> content in the subsurface, which enhances natural biodegradation of organic <br /> compounds. <br /> AS/SVE is a viable technology to remediate the petroleum hydrocarbon source area at Plant <br /> 33 due to the following site conditions: <br /> • Primary constituents of concern (i.e., BTEX and TPH as gasoline) are <br /> VOCs. <br /> quarierly.rep <br />