ARCHIVED REPORTS XR0012552 - Laserfiche WebLink

Home Browse Search

Wit 51 7�;i! r yr, ~ b ih 1 5-3 ' Groundwater Remediation The existing on-site monitoring and recovery system installed by. ks GR and EMCON should be retained and utilized. No additional monitoring or recovery wells are necessary. on-site �. The permit required for discharging the water pumped by the recovery system into the RWCF sanitary sewer system should be t = renewed. Conversations with the RWSF personnel indicate that renewal Of the discharge permit and continued pumping should not be a 1.41 problem, as long as hydocarbon constituents in the water t _ combustible levels. . are below Soil Remediation i ' Based on the soil and groundwater conditions at the site, two possible soil remediation techniques are discussed below. Both are considered to be applicable and feasible alternatives, but in situ aeration is recommended as the most effective means of remediation. ARCO and RC will evaluate the method which will be sOilthe h.. most effective at the site. In-Situ Aeration. An in-situ aeration the system is recommended as most effective means of eliminating hydrocarbon vapors from the soil, as well as the groundwater beneath the site. It would consist ` of a system of vertical, manifolded, vapor extraction wells connected to a single vacuum system. The vacuum system would be located in the northwest corner of the site, as far 'as possible from residential areas. The vapors recovered through the system would be incinerated, adsorbed through carbon adsorption, or discharged directly to the atmosphere. If hydrocarbon vapors are to be discharged directly from ., this system, an aeration permit must be obtained from the San Joaquin County Air Pollution Control District. Soil Flushing. An alternative to in situ aeration is soil flushing. Method involves using water to "flush" hydrocarbons out of the soil into the groundwater system. This method would be effective at this site because of the silty to sandy soils, the shallow groundwater, and the functioning recovery system. f Additional Investi ative Work In addition to the following investigative workisrecommended ndwater dforoil the sitediation, the Work Plan and Permits. Prior to performing additional investi- gativework at the site, a detailed work plan ;should be prepared in accordance with San Joaquin County requirements.. Necessary permits would be obtained for drilling, encroachment, discharge, and aeration 'purposes.