Technical Reference for the Mid-Continent Region: Hydrologic Considerations for Permitting and Liability Release

摘要

Coal mining, like any other activity that significantly disturbs earth materials, has the potential to adversely affect the quality and quantity of surface and ground water within the vicinity of the mining operations. Adverse impacts may include decreased water availability, increased mineralization and changes in stream loading. Proper planning of the mining operations, along with contemporaneous reclamation, can greatly decrease or prevent unwanted effects and restore or enhance premining hydrologic conditions. Public Law 95-87, the Surface Mining Control and Reclamation Act of 1977 (SMCRA), requires coal mining and reclamation activities be conducted in a manner that minimizes disturbance to the existing hydrologic balance and prevents long-term adverse impacts to areas both on and off the permitted site (30 CFR 780.21(h)). The term hydrologic balance refers to the relationship between the quality and quantity of water flowing into, stored within, and flowing out of a hydrologic unit. A hydrologic unit may be a surface-water drainage basin or subsurface soil or rock layers that store and transmit water. Regulations also require the mining operation be designed in a way that will prevent material damage to the hydrologic balance outside the permit area (30 CFR 780.21(h)). The definition of material damage has not been standardized since it is specific to each mine site. In general, material damage implies some functional impairment of surface lands, features, structures, facilities, or water resources that results in the lands inability to support current or reasonably foreseeable uses. The consequences of material damage may include a significant loss in productive capability or loss of income from the land. Hydrologic balance and material damage are central concepts for all hydrologic considerations for permitting and liability release.