Environmental Control Technology Survey of Selected US Strip Mining Sites. Volume 4. Evaluation of Effluent Guidelines for the Coal Mining Industry

摘要

An evaluation is made of the effectiveness of the federal Office of Surface mining coal mine wastewater effluent limitations as they relate to the Surface Mining control and Reclamation Act of 1977 (P.L. 95-87). The act was formulated to protect society and the environment from the adverse effects of surface coal mining operations; it also requires that an adequate coal supply be ensured to meet the nation's energy requirements. To achieve these objectives, an examination of preceding state and federal guidelines is required. At 21 study sites, it was found that compliance with state regulations was generally achieved more often than compliance to the promulgated EPA guidelines. Non-compilance was a result of many hard-to-quantify factors including: dynamic hydrologic conditions, changing mine locations through time, noncontinuous manual treatment strategies, and economic considerations. Changes in the values of water quality variables in the mining environment can be a result of geological and hydrological constraints, as well as inherent random error. This suggests that the promulgation of rigid guideline values that can be exceeded is not the best approach. Rather, statistical methods that recognize sufficiently long recurrence intervals can be used to describe natural conditions more accurately. The variables regulated by the EPA (iron, manganese, total suspended solids, and pH) are not the most toxic commonly present and controllable. Iron and manganese, especially, are present in overburden and are not limiting variables with regard to water quality. Concentrations of toxic trace elements in mine drainage are localized and are related to overburden/coal geochemistry. (ERA citation 06:029252)