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PROPOSED WORK PLAN FOR INSTALLATION OF MONITORING WELLS AT TRACY, CALIFORNIA SCS Engineers (SCS) on behalf of City of Tracy (City) proposes to place 3 monitoring wells at the City owned site (Assessor No. 253-11-22) near Tracy Municipal Airport where the excavated soil from Schulte Road extension will be bioremediated. These wells are placed to set a baseline before starting the bioremediation. The locations of three proposed monitoring wells are shown in Figure 1. Wells are expected to be approximately 30 feet deep and will penetrate approximately the first ten feet of groundwater bearing strata. A detailed boring log will be recorded by the Field Geologist and will denote sample's locations, lithology of sediments encountered, depth to groundwater, and well construction details. The wells will be installed using 4" Schedule 40 PVC Casing, 0.02 inch slotted sections in the aquifer and blank sections from the aquifer up to ground surface. Lonestar #3 sand will be placed in the annular space to two feet above the perforated casing. A one to two foot thick bentonite seal will be put above the sand, and the wells will then be grouted to ground level. A locking well cover will be cemented in place over the wells head at least one inch above the surrounding surface. A schematic showing a typical monitoring well construction is present on Figure 2. Development of the wells will be completed using a submersible pump. After the wells are purged, water samples will be acquired. Soil samples would be acquired at five foot intervals and at the soil groundwater interface, as well as a groundwater sample. All sampling containers will be labeled immediately after the samples are collected. Samples will be kept in cold packs until received by the laboratory. At the time of sampling, each sample will be logged on a Chain-of-Custody form which will accompany the sample to the laboratory. All samples will be tested by EPA Protocol 8015 for Total Petroleum Hydrocarbons, 8020 for Benzene,Toluene, Ethylbenzene and Xylene (BTEX) and 418.1 for Total oil and grease. Once the field work and chemical testing is completed, a report will be prepared by SCS which will include a summary of all activities completed. Boring logs, well construction diagrams, would be placed as an appendix. The chemical test results will also be provided. Level D safety protection consisting of steel-toed boots, gloves and hard hats, will be provided. Respirators filled with organic vapor cartridges will also be kept on hand in case they are needed. The drill cuttings will be kept on site, sandwiched between two layers of polyvinyl cover pending receipt of sample analyses results. There upon, proper disposal of the cuttings will take place. Water from the development of the monitoring wells will be kept on-site in a 55-gallon drum and disposed of properly upon the receipt of sample analytical results. Quarterly monitoring of the soil and groundwater will be done during the entire duration of bioremediation.