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RPR 20 194 03:51PM OGDEN PROJECTS ENVIRONMENTPL DPT P.9/10 Each well will first be sampled with a clear acrylic bailer to visually inspect for hydrocarbon layer or sheen. If no product layer of sheen is observed on the water, the well will be developed by surging, pumping or bailing. Surging along the screened interval of the well may be performed to draw the sediment from the formation into the filter pack and the well and to set the sand pack. Well development will include swabbing and purging until ground water is reasonably free of suspended solids. Development will continue until the discharge runs relatively clear of fines. Approximately 5 to to well volumes are usually removed from each monitoring well. Discharge water will be stored in 55-gallon drums and left on site for later discharge or disposal, depending on laboratory results. ua ivment Decontamination To reduce the potential for cross-contarnivation between wells, developing equipment will be washed in a trisodium phosphate or lab grade detergent solution and rinsed in distilled water or steam cleaned prior to use in the next monitoring well. Well—survey All four of the wells will be surveyed for well location and elevation above mean seal level (amsl) so that subsequent water-level sounding data can be utilized in determining groundwater flow directions and gradient. The locations of the monitoring well and the elevation of the north side of the top of the PVC casings will be surveyed and tied into permanent markers, if readily available. Survey accuracy will be 0.1 foot for the 'V and'y' coordinates and 0.1 foot for the "z' coordinate. The depth to static groundwater will be measured from a set location at the top of the PVC casing. The depth of water will then be subtracted from the elevation of the top of the well casing to provide a groundwater elevation for each monitoring well location. GROUNDWATER MONITGRWG Water Level Measurements Water elevations of all four wells will be measured prior to purging and sampling the wells. The measurement protocol is as follows: 1. The welts will be opened and allowed to equilibrate with the atmosphere. 2. The water level probe will be decontaminated in a trisodium phosphate wash, followed by a distilled water rinse, prior to use in each well. 3. Water level measurements will be made using a conductivity-based water LveI meter. Depth to water is generally treasured from a surveyed mark on the north 3