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Title: Hydrologic investigation and remediation of a post-remining acidic seep

Conference ·
OSTI ID:588790
 [1];  [2]
  1. Bureau of Mines, Pittsburgh, PA (United States)
  2. Aloe Holding Company, Neville Island, PA (United States)

Surface remining of coal pillars in abandoned underground workings in the Pittsburgh seam in southwestern Pennsylvania has often resulted in post-remining discharges whose water quality is the same or better than the pre-existing discharges. However, at one such operation in Washington County, PA, an increase in contaminant loading occurred at an outcrop seep after remining. This problem was believed to be at least partly related to a small unstrapped area of the old deep mine workings immediately upgradient from the seep. A hydrologic investigation that included a chemical tracer test, slug tests in the remined spoil, and water quality monitoring indicated that the mine pool in the old workings discharged through the seep. However, the water in the mine pool and much of the remined spoil was consistently alkaline; this suggested that the acidic water may have originated in other areas of the spoil and old workings, and passed rapidly to the seep through a highly transmissive portion of the spoil. Acting on this assumption, the mine operator successfully implemented a remediation scheme in which the spoil was excavated to intercept the acidic spoil water. The excavation was then re-emplaced with an anoxic limestone drain at its base. The drain now serves both to add alkalinity to the water and to divert the seep to an area where metals can be removed easily via precipitation in wetlands.

OSTI ID:
588790
Report Number(s):
CONF-9605286-; TRN: 98:001296-0024
Resource Relation:
Conference: 13. annual meeting of the American Society for Surface Mining and Reclamation (ASSMR), Knoxville, TN (United States), 18-23 May 1996; Other Information: PBD: 1996; Related Information: Is Part Of Successes and failures: Applying research results to insure reclamation success; Daniels, W.L.; Burger, J.A.; Zipper, C.E. [Virginia Tech, Blacksburg, VA (United States). Depts. of Crop and Soil Environmental Sciences and Forestry] [eds.]; PB: 889 p.
Country of Publication:
United States
Language:
English