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Mr. Harlin Knoll Page 2 of 3 depth of approximately 50 feet bgs, and will be constructed of 2-inch diameter, Schedule 40 PVC casing and 0.010" slotted screen. To accommodate water level fluctuations, the well will be screened from 50 feet bgs to 5 feet above static depth to water. Filter pack will consist of 2/16 sand, from the bottom of the well to approximately 2 feet above the top of the well screen. The remaining annulus will be completed with 2 feet of hydrated bentonite overlain by neat cement grout to the surface. The well will be fitted at the surface with a watertight, traffic-rated well box and locking well cap. Drilling and well installation will be conducted under the supervision of an experienced geologist. The boring will be sampled at 5-foot intervals for stratigraphical concerns. All soil samples will be classified in accordance with ASTM Designation D2488-90, which is equivalent to the Unified Soil Classification System. Up to three soil samples from the boring will be submitted for laboratory analysis, including the sample collected from the capillary fringe. Samples selected for analysis will be immediately capped, labeled, and placed in an ice chest refrigerated to a temperature of approximately 4°C for shipment to a State-certified laboratory under chain of custody protocol. Soil samples will be analyzed for total petroleum hydrocarbons as gasoline and (TPHg) using EPA Method 8015M, benzene, toluene, ethylbenzene, xylenes (BTEX) and methyl tent butyl ether using EPA Method 8020, and total lead using EPA Method 6010 or equivalent. Any positive results for MTBE will be confirmed using EPA Method 8260B. Well Development, Surveying and Groundwater Sampling The elevation of the well casing collar will be surveyed to an accuracy of 0.01 feet. A minimum of 48 hours after completion, an experienced field technician will measure static depth to water, and then develop the well by pumping and surging until turbidity is minimized. A minimum of three casing volumes will be purged from the well. Groundwater samples will be collected into the appropriate containers after pH, temperature, and electrical conductivity have stabilized and water has recharged to minimum of 80% of static levels. The samples will be placed into an ice chest refrigerated to a temperature of approximately 4°C for shipment to a State-certified laboratory under chain of custody protocol. Groundwater samples will be analyzed for BTEX and MTBE using EPA Method 8020, TPHg using EPA Method 8015M, and lead using EPA Method 6010 or equivalent. Reporting Following the receipt of analytical data, Ground Zero will prepare a technical report describing field activities, results, conclusions, and recommendations for submittal to EHD and Regional Water Quality Control Board (RWQCB). Protocols and Safety All field activities performed at the site will be conducted in accordance with Ground Zero's Quality Assurance/Quality Control Plan and Site Specific Site Safety Plan on file with EHD. Drill cuttings and rinsate generated from well purging and equipment decontamination will be G:\Data\GROLJNDZE\KNOVIUS-HAM\REPORTS\WKPLAN—MW8R.doc