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. added if necessary. Directly above the sand a 3 foot plug of hydrated bentonite chips will be placed. Above the plug a seal of cement grout will be placed to the surface. The top of the casing will be capped and a traffic box and will be cemented in place around and above the top of the casing. The cement or bentonite grout will be placed an the annulus by the use of a trxme pipe if the total annulus seal distance is over 30 feet. ( Bul . 74-90 Cal . Water Well Standards) The well will be developed by bailing within a day of drilling to remove most of the sediment within the casing and to remove bridging fines within the slots and sand pack. This will be done by surging using the well water if possible, of not then only potable water may be used. A log of the amount of .introduced water will be kept and its use will be kept to a minimum. Bailing and surging will continue until the water does not contain any fine silt and or clay. The amount of water added to the well to develop it must be removed from the well during development. All purged water will be stored in drums, the drums will be sealed and left on site until the condition of the water is assessed. • Sampling Protocol : Soil samples will be obtained from the core samples taken every 5 feet during drilling. A split spoon sampler with brass sleeves will be used. The samples will remain within the brass sleeve covered with aluminum foal, and capped with the plastic caps which are supplied with the sleeves. The plastic cap will be taped to the brass sleeve using duct tape so that an air tight seal is obtained. Samples will be marked and placed in a cooler of ace until they are turned over to the laboratory, which should be within 48 hours of the drilling. A Chain of Custody will be filled out by the sampler and signed by the laboratory. The split spoon sampler and the brass sleeves will be decontaminated before each sampling event. They will be washed with Tri-sodium phosphate detergent and water and rinsed thoroughly with clean water. Core samples can be measured with a OVA meter and the readings will be recorded on the drill log. These readings will be used to help select the cores to be sent for laboratory analysis. A minimum of two core samples will be sent for analysis. One of these samples will be from the capillary fringe. If possible, one sample will be sent which is thought to be free of contaminant and one that is thought to be contaminated. One . sample will be sent for at least every 15 feet of drilled hole above the water table. If the water table is at 10 feet or less Page 5