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material The filterack material was brought to approximately 2-feet above the top of P g PP Y ' the well screen An approximate 2-foot thick bentonite seal was placed above the filter pack and hydrated with clean, potable water and allowed to sit for 30-minutes prior to placement of the cement seal The remaining borehole annulus was sealed with neat ' cement grout The neat cement grout consisted of approximately 5 gallons of water per 94-pound sack of Portland cement Because the top of the sanitary seal was located less ' than 30-feet bgs, the SJCEHD approved a request to emplace the grout by free-fall provided sufficient time was allocated for hydration of the bentonite seal The wells were completed with flush-mounted vault boxes to minimize disturbance to site activities ' After well installations were completed, the elevation of the to of the monitoring well P P g ' casing was surveyed in order to establish top-of-casing elevation Additionally, as required by AB 2886, northing and eastmg latitude and longitude information was also generated for the State's Geo Tracker database system 1 Monitoring well construction details are shown on the lithologic logs in Appendix B of ' this report 4.2.2 Monitoring Well Development t• All monitoring wells were developed using a combination of surging, bailing, and ' pumping until the well produced clean, relatively sediment-free water Development activities were conducted five days after installation of the last well Well development ' records were maintained and copies are contained in Appendix C of this report 4.3 GROUNDWATER SAMPLING ' In order to evaluate groundwater flow and chemistry, the newly installed groundwater ' monitoring wells were measured for static water level, sampled and analyzed Groundwater monitoring wells were purged and sampled using low-flow sampling techniques Prior to purging and sampling, the depth to groundwater in each of the ' monitoring wells was measured using an electronic water level indicator and recorded in a well purging record form ' Monitoring wells were purged using a variable drive electronic submersible pump The well screen information was used to establish the pump intake setting in the monitoring 1 well Typically, the intake of the pump is set at the approximate midpoint of the screened • interval during low flow sampling However, because groundwater occurs under serm- ' confined conditions, the pump intake was placed across from the lithologic unit where ' 6 V\Goodwin ProctorTinal Report doc