Abstract: The utilization of saline coal mine waters is considered to be the most adequate method of solving ecological problems caused by this kind of water in Poland. In the case of most concentrated waters, the so-called coalmine brines, the method of concentrating by evaporation in a twelve-stage expansion installation or vapour compression is applied, after which sodium chloride is manufactured. A considerable restriction in the utilization of coal mine brines is the high energy consumption in these methods of evaporation. An obstacle in the application of low energy evaporation processes, e.g. multi-stage flash, is the high concentration of calcium and sulfate ions in the coal mine brines. The present paper deals with the application of nanofiltration in the pretreatment of the brine. The application of nanofiltration membranes with an adequate pore size, including charged membranes, makes it possible to decrease the concentration of divalent ions in the permeate practically without any changes in the concentration of sodium chloride. Then the permeate may be concentrated in a multi-stage evaporation process, e.g. MSF, without any risk of the crystallization of gypsum. A combination of NF and MSF ought to set down the unit costs of the concentration of coal mine brines below those of mere evaporation.

Abstract: The UK has a legacy of pollution caused by discharges from abandoned coal mines, with the potential for further pollution by new discharges as groundwaters continue to rebound to their natural levels. In 1995, the Coal Authority initiated a scoping study of 30 gravity discharges from abandoned coal mines in England and Scotland. Mining information, geological information and water quality data were collated and interpreted in order to allow a preliminary assessment of the source and nature of each of the discharges. An assessment of the potential for remediation was made on the basis of the feasibility and relative costs of alternative remediation measures. Environmental impacts of the discharges and of the proposed remediation schemes were also assessed. The results, together with previous Coal Authority studies of discharges in Wales, were used by the Coal Authority, in collaboration with the former National Rivers Authority and the former Forth and Clyde River Purification Boards, to rank discharge sites in order of priority for remediation.

Abstract: Rodiek, J., Verma, T.R. and Thames, J.L., 1976. Disturbed land rehabilitation in Lynx Creek Watershed. Landscape Plann., 2: 265-282. The Lynx Creek Watershed is located on the Prescott National Forest about 8 km south of Prescott, Arizona. The watershed, with an area of 7304 ha, has experienced intensive copper and gold mining activities in the past. Approximately 13% of the area still consists of patented mining claims (mainly copper). There are numerous abandoned mine shafts, waste dumps and mine tailings in the area. Past mining activities in the watershed have caused significant deterioration in water quality within and downstream from the mining sites. Mine drainage includes water flowing from mine shafts, surface runoff and seepage from mining dumps. Drainage from the numerous old mining sites contributes to the toxic mineral and sediment pollution of the water resources in the area. The pollutants in the form of dissolved, suspended or other solid mineral wastes and debris, enter in the streams of ground water. Aquatic life and recreation potential of the watershed is greatly reduced by the water pollution problem from the abandoned mines. The pollutants from the abandoned mines enter into Lynx Lake which is located 10 km southeast of Prescott. Lynx Lake, a trout fisheries lake, was created by a dam built in 1963 by the Arizona Game and Fish Department. The lake is 22 surface hectares in size with the storage capacity of 1.85 x 106 m3. The average yearly flow of sediment into the lake is 2900 m3. The sediment is slightly acidic and has a high concentration of copper, manganese, iron, zinc, and sulfates. The Sheldon dump and tailings pond are considered two major sources of pollution. Increasing need to direct additional attention toward mineral related problems made it necessary to coordinate U.S. Forest Service efforts with others involved in mining and reclamation. The Forest Service started SEAM (Surface Environment And Mining) in 1972 to coordinate interagency reclamation efforts. The Sheldon Mine dump and tailings pond were undertaken as a reclamation project through the coordinated efforts of the Forest Service, and the School of Renewable Natural Resources, University of Arizona at Tucson. The project is aimed at reclaiming some of the abandoned spoils in the Lynx Creek watershed and monitoring of water quality in the creek to evaluate the effectiveness of reclamation procedures. The reclamation approach includes recontouring, revegetating, drainage control and visual impact modification activities. The results to date have been encouraging. There was an excellent vegetation cover established within 5 weeks of seeding. Runoff and sediment control on the regraded slopes seemed quite effective. The methodology and technological experience gained from the reclamation project will provide invaluable information for reclaiming any abandoned mining sites within the Ponderosa Pine Ecosystem.