Strip coal mining and mined-land reclamation in the hydrologic system, southeastern Montana. Project completion report

Technical Report · Fri Dec 01 04:00:00 EST 1978

OSTI ID:5506640

Van Voast, W A; Hedges, R B; McDermott, J J

Coal beds which are locally important aquifers for southeastern Montan's agricultural economy are being removal as mining development occurs. Overburden rock materials (spoils) replace the coal beds as aquifers. As mine pits are backfilled, ground waters readily re-enter the spoils. The chemistry of spoils waters in diverse, reflecting the lithologic and geochemical variability of overburden materials. At Decker, predominant ions in spoils water are sodium and bicarbonate; at Colstrip, they are magnesium, calcium, and sulfate. Statistically, spoils waters in both areas are more highly mineralized than nearby stock and domestic waters. Column backing experiments conducted with spoils produced leachates that were chemically similar to waters found in the field. First pore volumes of the leachate were also chemically similar to saturated-paste extracts. The relationships between saturated-paste-extracts quality and spoils-water quality were utilized to develop generalized nomographs for predicting spoils-water cation concentrations from pre-mining paste-extract chemistry.

• Research Organization: Montana Bureau of Mines and Geology, Butte (USA)
• OSTI ID: 5506640
• Report Number(s): PB-301253
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010900* -- Coal
Lignite
& Peat-- Environmental Aspects
510500 -- Environment
Terrestrial-- Site Resource & Use Studies-- (-1989)
520200 -- Environment
Aquatic-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
AQUIFERS
COAL MINING
DISSOLUTION
ENVIRONMENTAL EFFECTS
ENVIRONMENTAL QUALITY
GROUND WATER
HYDROGEN COMPOUNDS
LAND RECLAMATION
LEACHING
MINING
MONTANA
NORTH AMERICA
OVERBURDEN
OXYGEN COMPOUNDS
ROCKY MOUNTAIN REGION
SEPARATION PROCESSES
SURFACE MINING
USA
WATER
WATER QUALITY