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typically set 1/2-inch above grade to minimize surface water from entering the vault. In areas that may be plowed for snow removal, the vault is set flush with the surface to prevent damage to the vault by a snowplow. After completion,the well is thoroughly developed to remove residual drilling materials from the wellbore, and to improve well performance by removing fine material from the filter pack that may pass into the well. Well development techniques used may include pumping, surging, bailing, swabbing,jetting, flushing and airlifting. All development water is collected either in drums or tanks for temporary storage and is properly disposed of depending on laboratory analytical results. To minimize the potential for cross-contamination between wells, all development equipment is either steam cleaned or properly washed prior to use. At the request of the client, and approval of the regulatory agency,the well may be developed before placement of the bentonite plug and annular seal. Soil Cuttings from Drilling Operations Soil generated during drilling operations will be placed in DOT rated 55-gallon drums and stored on-site. The soil will remain on-site until the proper method for disposal is assessed. Sampling Soil Cuttings Sampling of the soil cuttings is performed under the direction of a registered geologist or civil engineer. Prior to collecting soil samples,Delta personnel will measure and calculate the volume of soil in the drums. Soil samples are typically collected from 0.5 to two feet below the surface of the drum. In some instances, two to four soil samples may be collected from each sampling interval and composited into one prior to laboratory analysis. The soil samples are collected in cleaned, brass or stainless tubes of varying diameter and lengths (typically two x six inches) or other appropriately cleaned sample containers. A hand-driven sampler holding the sample container may be used. To reduce the potential for cross-contamination between samples, the sampler is cleaned between each sampling event. Upon recovery, the sample container is sealed to minimize the potential of volatilization and cross-contamination prior to chemical analysis. Soil sampling tubes are typically closed at each end with Teflon sheeting and plastic caps. The soil sample is collected, labeled and handled according to the Quality Assurance Plan. Ground Water and Liquid-Phase Petroleum Hydrocarbon Depth Assessment A water/hydrocarbon interface probe is used to assess the liquid-phase petroleum hydrocarbon (LPH) thickness, if present. A water level indicator is used to measure the ground water depth in monitoring wells 5