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A minimum of 24 hours will elapse between MW development and sample collection. If possible, five (5) casing volumes of groundwater will be extracted (purged) from the MW prior to the collection of groundwater samples for analysis to maximize the possibility of collecting a water sample representative of the formation water. Should recharge of the well be slow, groundwater samples will be collected after sufficient groundwater accumulates in the well casing to provide the requisite volume for the requisite analysis. Groundwater samples will be collected using a Watera positive displacement pump attached to new, dedicated 1/z' high density polyethylene tubing inserted into the well casing for purging and sample collection. Each sample will be labeled and placed in a cooled ice chest for transportation to a state certified laboratory for analysis of TPH-d and TPH-mo. A completed chain of custody documenting sampling data, and analysis to be performed will accompany the samples from the field to the analytical laboratory. The soil cuttings and equipment decontamination liquids generated during the drilling of the boring will be properly contained pending disposal of these materials by the client. 3.5 Hydraulic Conductivity Testing Following development of the two new monitoring wells, CE proposes to perform hydraulic conductivity testing on the confined wells (e.g., slug test). The purpose of the test will be to collect data to enable better definition of the hydraulic conductivity at the site. The test will consist of logging and measuring the aquifer response in the observation wells from the introduction of a cylinder or "slug" (e.g., capped PVC tubing filled with sand for ballast). The transducer is placed in the well below the pre-test water level a sufficient depth to permit testing (adding and/or removing a „slug” of water). An instrument will record water-depth above the transducer before, during, and after the "slug" is introduced. The "slug" is introduced suddenly (either raising or lowering the water-level) and a series of water-level versus time measurements are made as the water-level changes toward an equilibrium situation. Based on the results of the initial testing, additional hydraulic conductivity testing may be implemented and will be dependent on the aquifer response. Any additional testing will be documented in the next monitoring report. 4.0 Sample Containers, Preservation, and Documentation Soil will be collected in 6-inch by 2-inch brass sample sleeves (hollow stem). After removal from the sample barrel the ends of the soil sample containers will be covered with Teflon® plastic sheeting and sealed with slip-on plastic end caps. Groundwater samples will be collected in unpreserved 1-liter amber glass bottles equipped with screw-on caps. Samples of soil and groundwater collected during the performance of the scope of work will be properly preserved and documented. After collection of the sample a label containing the following information will be CE Project No.99R-4041 Additional Investigation Work Plan 5