Optimized coverage of potash tailings piles

Saline contaminants from potash mining endanger aquatic ecosystems. Uncovered potash tailings piles release high amounts of chloride and sodium. Conventional coverage systems with a transpiration-intensive vegetation on a soil layer reduce percolation water only to some extent and does not protect the surrounding environment sufficiently. Powerful sealing layers are used to cover other mining deposits, but are still uncommon for potash tailings piles. In this paper, I study how to complement conventional coverage with additional sealings to minimize the release of contaminants effectively. I investigate a yet uncovered potash tailings pile in Germany. I model water balance parameters and calculate percolation rates for 44 different coverage systems. The results show that sealings always outperforms (max. 24.8 % of P) conventional coverage without an additional sealing (26.5 % of P). Site-specific coverage reduces percolation water more than uniform coverage and requires less layer material. A sealing works best on slopes with a northern orientation, soil cover systems perform better on southern slopes. I conclude that site-specific coverage systems are most effective to improve water quality in post-mining landscapes.