WORK PLANS - Laserfiche WebLink

Home Browse Search

feet bgs, with an end plug installed on the bottom of the well. A filter pack consisting of No. 3 silica sand will be carefully poured through the augers as they are removed. The top of sand will be maintained a maximum of 3 feet below the bottom of the augers as they are withdrawn from the boring. The top of the sand filter pack will installed to about 2 feet above the top of the well screen. A 3-foot thick bentonite seal will be placed above the filter pack by pouring through the augers. The bentonite will be allowed to hydrate for a minimum of 45 minutes before grouting. The bentonite seal will be hydrated with potable water at a rate of 5 gallons per foot of bentonite. A concrete grout seal will be mixed and placed from the top of bentonite to ground surface in accordance with ASTM D5092. The grout seal will be allowed to cure for a minimum of 24 hours before the well is disturbed. Well surface completion will be similar to that of the existing wells and will facilitate use of product-specific recovery pumps, including pressurized air and discharge pipelines. A1.2 Well Development At least 24 hours after the grout seal has been placed,the wells will be developed as described below. A1.2.1 Recovery Well Development Initial development of the recovery wells will consist of surging with a bailer, surge block or equivalent. The wells will be gently surged for approximately one hour by moving the device up and down in such a manner as to avoid damage. After about one hour, the well will be bailed or pumped for up to an additional four hours or until produced water is clear. Since these wells are not to be used for potable water supply, and because of the presence of petroleum hydrocarbons, they will not be disinfected. After development, pumping equipment used in other extraction wells may be reinstalled and connected to existing utilities and discharge lines via new corridors and connections. A1.2.2 Monitoring Well Development Initial development of the monitoring well will consist of surging with a bailer, surge block or equivalent. The well will be gently surged for approximately one hour by moving the device up and down in such a manner as to avoid damage. After about one hour, the well will be bailed or pumped for up to an additional four hours or until produced water is clear. Since this well is not to be used for potable water supply, and because of the presence of petroleum hydrocarbons, it will not be disinfected.