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• Open all monitoring wells at the site and allow them to equilibrate approximately 15 minutes. Denote time and visual observations regarding well access, condition, security, etc. in logbook. • Obtain initial depth to groundwater level readings from the point of survey mark, or from the North side of the top of the PVC casing, if not point of survey mark is present. Readings will be measured to the nearest 0.01 foot. Denote time and readings in logbook and on forms provided. • Obtain depth to casing bottom for each well.Readings will be measured to the nearest 0.01 foot. Denote readings in logbook,and compare with boring log information. • Calculate the volume of standing water in each monitoring well. Denote the volume calculated for each well in logbook and/or on forms provided. • Alternate surging/swabbing of the screened interval and purging of the water: — Surging/Swabbing: Using either a surge block, the purge pump, or a heavy bailer, swab the screened portion of the well by lowering the surge equipment to the bottom of the well, rapidly raising and lowering the equipment in 2-foot intervals in a plunger-like fashion. This should force water in and out of the screened interval. Repeat the surge/swab at least 10 times at each 2-foot interval.Then swab the next 2-foot screened interval. Follow each round of surging by purging. — Purging: Following each round of surging of the screened interval,the well shall be purged of water.Be sure to lower the bailer to the bottom of the well in order to "grab" the silts and clays that have settled to the bottom of the well. If a well has a large portion of fines, then the purging may be performed only using a bailer, since silts and clays can cause malfunction in the pumps. • Please note, to develop the entire screened interval,water must be present over the entire length of screen. In wells with little water or with very poor recharge,distilled water may be added to the well to ensure adequate development of the well. If water is added,the volume of water added must be documented,and the water being used should be sampled for the presence of contaminants. • Continue the process until the entire screened interval has been adequately swabbed and purge water is relatively clear of fine material. • Contain all purge water in the drums or other containers provided. Denote the date, time and origin of the water on the containers. Include calculation of the volume of water removed from each well and observations of the presence of sediments and color/odor of water, etc., in the logbook and on the forms provided. • Obtain final depth to groundwater level readings from the point of survey mark,or from the North side of the top of the PVC casing, if not point of survey mark is present. Readings will be measured to the nearest 0.01 foot. Denote time and readings in logbook and on forms provided. • Conduct final decontamination procedures of any field equipment that is not disposable. • Close and secure each well upon completion of field activities. Ensure that all water storage containers are closed and secured and that the site is clean. SOP MW Install&Dev 6 of 6 August 2011