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PHASE 1 WORK PLAN SCOPE OF WORK This work plan provides for drilling three soil borings by hollow stern auger with soil samples extracted at five foot intervals Soil borings will be placed so that the resulting borehole maybe used to construct a monitoring well Monitoring wells are to be constructed and sampled if it is determined by the PHS- EHD and Foothill Engineering that the contamination may have reached the groundwater table After all sample analysis is completed, an engineering report will be published All items of work described by this work plan are subject to the approval of PHS-EHD and the California Underground Storage Tank Cleanup Fund SOIL BORE HOLE PLACEMENT The area surrounding the fuel dispenser islands is paved with concrete and has a metal framed canopy covering the islands and the truck scale to the east of the islands San Joaquin County Flood Control's latest ground water table records are for the year ending December 31, 1997 These records show the ground water to be between sixty and seventy feet below the surface and the hydraulic gradient to be down slope to the east This Phase 1 work plan would auger three bore holes at the site (see soil bore hole layout attached) Bore hole BH 41 is located under the canopy about four feet west of the westerly fuel island BH#2 is located in the mow strip north of the scale house, between the truck scale and the Wilson Way curb BH 43 is located to the south of the scale house in the mow strip BH #2 and BH 43 should both be down gradient from the dispenser islands BH #1 will be slightly up gradient from the pump islands It is proposed that these soil borings be continued to a depth approximately ten feet below the present water table If it is obvious that the water table has been contaminated, a monitoring well will be installed in the bore hole to save the cost of grouting the bare hole POSSIBLE HAZARD DRILLING CONDITIONS (Locate all Utilities Before Drilling) BH #1 is restricted by the canopy to a low headroom drill rig and may interfere with underground utilities BH 42 and BH #3 are located within three feet of the back of roadway curb and may conflict with public utilities MONITORING WELL INSTALLATION If the soil samples or site conditions indicate that the contamination is at or near the existing water table, a 2" PVC monitoring well will be installed (see attached detail for well construction) The monitoring well will be purged and sampled as per standard practices of the industry SOIL SAMPLING PROCEDURE The planned soil bonngs will be sampled at five foot intervals starting at a depth of 10 feet Each sample will be extracted with a standard split spoon sampler with brass BX liners Soil samples will be logged and classified by the Unified Soil Classification System All soil samples will be sealed and placed under ice Samples will be transported under chain of custody to Sherwood Labs for analysis Spoil from the soil boring will be placed in standard sealed drums and stored onsite Drums that contain contaminated soil will be disposed of at an approved disposal site 2