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Mr. James Barton,PG 24 April 2014 Page 7 Well Development The new monitoring wells will be developed at least 48 hours after installation. The purpose of well development is to stabilize the filter pack and remove fines from the filter pack and well screen. Development will be completed according to the following general procedures: • All downhole equipment will be decontaminated by steam cleaning or washing in a solution of laboratory-grade detergent prior to, between, and after use; • The total depth of the well and the water level will be measured; • Approximately one casing volume of water will be removed from the well using a submersible pump or bailer; • The well will be surged for a period of 15 to 30 minutes; • Following surging, additional water will be removed from the well by bailing or pumping; • Periodically during development, water samples will be collected and analyzed for water quality parameters (pH, specific conductance, temperature, turbidity); and, • The process of surging and bailing or pumping will continue until a minimum of ten casing volumes of groundwater have been removed and water quality parameters stabilize_ Water purged from the wells will be contained in drums, labeled, and remain at the Site pending appropriate disposal. Groundwater Sampling At least 48 hours after well development is complete, groundwater samples will be collected from each well according to the following general procedures: • Purging and sampling equipment will be . cleaned in a solution of laboratory-grade detergent and distilled water and rinsed with distilled water; • The water level and total depth at each well will be measured and recorded; • Wells will be purged using the U.S. EPA Low Flow(Minimal Drawdown) Ground-Water. Sampling Procedures (U.S. EPA, 1996); Offsite Characterization Workplan engineers I scientists I innovators i i