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i • • 1 5.0 Construction Activities Implementation and Documentation The biosparge pilot test involves the performance of various field construction activities, including utility clearance, well installation, groundwater sampling, equipment installation, and waste handling. Upon completion of the pilot test, test results will be incorporated into the final design of the remedial system. These activities are presented in detail in the following subsections. 5.1 Utility Clearance Underground Service Alert (1-800-227-2600) will be notified at least 48 hours prior to sample collection to identify any buried utilities that may exist within the investigation area. In addition, a utility survey will be performed within the work area to identify any subsurface utilities prior to drilling. Prior to initiation of field work, the existing site-specific health and safety plan will be amended to include safety procedures for work to be performed during pilot testing as well as an activity hazard analysis. 5.2 Well Installation Prior to well installation, a drilling permit will be secured from the San Joaquin County Environmental Health Department. The well will be installed using a low -profile, track - mounted, sonic drilling rig. This type of drilling has an advantage of hollow -stem auger drilling in that sonic drilling in this case will provide much less drill cuttings to handle afterwards. During continuous -core drilling, a field boring log will be completed for each boring that describes the soil encountered, the depth at which groundwater is encountered, the static water level in the boring, and details of well construction. Soil samples will not be collected from the borings for chemical analysis. The biosparge well boring will be drilled to a total depth of 50 feet bgs. The well will have pre - packed 2 -foot screen and sand pack, extending upward from the bottom of the well. The well will be constructed of 2 -inch -diameter Schedule 80 PVC riser and screen. The screen will be 0.020 -inch slot size, appropriate for the poorly to well -graded sandy sediments encountered in the treatment depths at the site. The well will be completed by adding a seal consisting of one to two feet of hydrated bentonite pellets or chips on top of the sand pack, followed by sealing to the near surface using a bentonite grout. Surface completion will consist of a flush -mount traffic box surrounded by a concrete pad. A well construction diagram is presented on Figure 6. The wellhead will be equipped with 1 Biosparge Pilot Test Final. doc 5-1 Shaw Environmental, Inc.