Patent ID: 9732492
Date: 2017-08-15
CPC Classifications: B01D,B09B,B09C,C02F,E02D

Claim:
1. A method to dewater an extant stationary waste material deposit comprising an amount of waste material stored in a waste impoundment by removing particle-containing leachate from the extant stationary waste material deposit at depths below the phreatic surface in situ, said leachate removal improving the extant stationary waste material deposit for at least one of waste stability, waste removal, structural integrity, and/or reduction in the source of environmental contamination, the method comprising the steps of: installing a plurality of vertical dewatering wells in boreholes constructed in the extant stationary waste material deposit, wherein the extant stationary waste material deposit substantially fills the waste impoundment, each vertical dewatering well having an apertured well screen located within the vertical dewatering well; installing at least one of specialized completion materials around the well screen and within each of the vertical dewatering wells, each well screen adapted to filter particles suspended in the leachate, which particles are drained from the extant stationary waste material deposit, to prevent clogging of the at least one completion materials and the apertures in the well screen, wherein the at least one specialized completion material is selected from the group consisting of: installing at least one well pump in each vertical dewatering well, the well pump in each vertical dewatering well adapted to concurrently remove the leachate from each vertical dewatering well at a controlled rate and create radial leachate flow through a saturated depth of the extant stationary waste material deposit to the vertical dewatering wells, and a gradual leachate level drawdown in the extant stationary waste material deposit wherein the at least one well pump is installed at a depth below the phreatic surface.