Abstract: When mining is completed the sites may be completely restored to the originalecosystem, rehabilitated for some desirable environmental characteristics, desirable alternative ecosystemscreated or just neglected. The strategy adopted will depend on the intended uses of the parts of theenvironment (including water) affected by the mining. An example of rehabilitation of a metal mine nearthe Australian Federal Capital is used to illustrate the problems that may be encountered. These include:lack of controls while mining is underway; catastrophic events, such as the collapse of a settling dam,lack of site specific understanding of pyrite oxidation processes, particularly those that are biologicallyenhanced; the need for adequate biological information on which to base decisions to meet biologicalinformation on which to base decisions to meet biological objectives. Experience has shown that biologicalcollections such studies should be stored in museums where they will be valuable for comparisons of changesover long periods.

Abstract: The use of an anaerobic digester slurry of cattle waste for the reclamation of acid mine water was examined. When the digester slurry was mixed with acid mine water, anaerobic digestion, including sulfate reduction and methanogenesis, was enhanced. In the mixture of acid mine water and the digester slurry, sulfate reduction proceeded without diminishing methanogenesis. The digester slurry and its supernatant (SDF-sup) showed a significant capacity to act as a strong alkaline reagent, and the pH of the acid mine water was markedly elevated by the addition of the digester slurry of SDF-sup even at the low ratio of 1% (v/v). Precipitation of heavy metals in the acid mine water occurred as the pH was elevated by the addition of SDF-sup. When the digester slurry was added at the ratio of 5% (v/v) to acid mine water which had been pretreated with SDF-sup, the rate of sulfate reduction increased with increasing the concentration of sulfate in the mixture up to about 1,400 mg·l-1. In acid mine water pretreated with SDF-sup and supplemented with the digester slurry at the ratio of 5% (v/v), the maximum amount of sulfate reduced within 20 d of incubation was about 1,000 mg·l-1, and the maximum rate of sulfate reduction was about 120 mg SO42-·l-1·d-1.

Abstract: The river water in Poland has, to a great extent, such a high salinity that it cannot be used as drinking water, agricultural or industrial water. A large environmental project is now under progress in Katowice, Poland, in order to eliminate the wastewater discharge from two coal mines — Debiensko and Budryk. The highly brackish water will be desalinated in a reverse osmosis plant, followed by vapor compression distillation with seed crystals (RCC), crystallization and sodium chloride drying. This zero discharge process will produce about 8,000 m3/d drinking water an 370 tonnes/d NaCl. The paper describes the design of the plant. Trial operation of pre-treatment and reverse osmosis in a pilot plant for design of the full-scale plant at Debiensko is described in a separate paper.