Laserfiche WebLink
column, "successful' air-lift pumping will occur. Air-lift pumping can continue as long as <br /> water is entering the well at a fast enough rate to maintain an aerated water column that <br /> extends to the top of the well. <br /> • Repeat the combination of pulsed jetting over the length of the well screen and air-lift <br /> pumping at least once. If the capacity of the well is not returned to near-original levels or if <br /> the clarity of the well water fails to improve after the second cycle, the nitrogen-jetting <br /> redevelopment process shall be continued until the capacity of the well and the clarity of <br /> the water cease to improve. <br /> B.15.6.2. Surge-Blocking Redevelopment Procedure <br /> • Lower the surge block into the well to a position below the water level in the well but above <br /> the top of the screened interval, if possible. Surging action should be initiated gently to <br /> loosen obstructing sediment. As the circulation improves during the redevelopment, more <br /> vigorous surging should be undertaken. <br /> • After operating the surge block in a given depth increment for several minutes, lower it to <br /> the next interval and repeat the surging action. This process should be repeated until surge <br /> blocking has been conducted in the entire screened interval. <br /> • After surge-blocking the entire screened interval, the surge block should be removed. <br /> Install a suction-lift pump intake and a submersible pump or a foot valve pump, and pump <br /> water from the well to remove the dislodged sediment. An effort should be made to pump <br /> accumulated sediment from the bottom of the well. Pumping should continue until the <br /> discharged water is clear and several bore volumes have been removed. <br /> • The process of surge blocking and then pumping should be repeated at least once. If the <br /> capacity of the well is not restored to near-original levels, or if the clarity of the well water <br /> fails to improve after only two surge-and-pump cycles, the complete process should be <br /> continued until the capacity of the well and the clarity of the water cease to improve. <br /> B.15.6.3. Suction-Lift Pumping <br /> Suction-lift pumping is not currently appropriate for NS groundwater monitor wells because of <br /> the greater depths to water. This section is included for reference only. Suction-lift pumping is <br /> most suitable to use in combination with either surge-blocking or nitrogen jetting. When used <br /> with either of these techniques, suction-lift pumping is an effective means of removing <br /> suspended sediment particles and accumulated sediment that have collected at the bottom of <br /> a well. When used alone, suction-lift pumping is capable of providing only limited improvement <br /> in the capacity of a well. <br /> When using suction-lift pumping in combination with surging or jetting, the suction-lift pump <br /> should be used to remove any accumulated sediment from the bottom of the well. This should <br /> be done before surging or jetting. Subsequently, the suction-lift pump should be used after <br /> each surging or jetting cycle to remove loosened sediment particles. Suction-lift pumping is <br /> conducted by simply installing the intake line in the well, connecting it to the pump intake port, <br /> and turning on the pump. Suction-lift pumping should then continue until the discharge water <br /> Daub &Associates, Inc. Page B-39 Natural Soda LLC 2022 SAP <br />