Atmosphere and temperature within a reclaimed coal-stripmine and a numerical simulation of acid mine drainage from stripmined lands

Thesis/Dissertation · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5228859

Jaynes, D B

Oxygen, O/sub 2/, and carbon dioxide, CO/sub 2/, and temperature were measured with depth along a transect of an acid, reclaimed coalstripmine over a two-year period. Most of the mine remains well oxygenated (O/sub 2/>10% by volume) down to 12 meters depth. At some locations, especially within 2 meters of the surface, variations in O/sub 2/ and CO/sub 2/ are correlated with changes in the spoil temperature. Spoil temperatures in layers below 3 meters remain in a range conductive to iron-oxidizing bacterial activity year around. Flux ratios of CO/sub 2/ and O/sub 2/ and source/sink rates of the two gases indicate that carbonate neutralization of the acid produced by pyrite oxidation is the dominant source of CO/sub 2/. In a second phase of the study, a numerical model describing the production and removal of acid and acid by-products from reclaimed coal stripmines is presented. Both direct oxygen and bacterially catalyzed pyrite oxidation was considered. Under all conditions modeled, excess acid, in the form of free hydrogen, must be removed if bacteria are to play an important role in accelerating pyrite oxidation. Leaching of the spoil by normal precipitation is insufficient in removing the excess hydrogen ion. Neutralization and buffering by the host rock are required for prolonged bacterial activity--the degree of hydrogen ion removal determining the maximum sustainable activity. At optimum conditions bacteria can greatly increase pyrite oxidation.

• OSTI ID: 5228859
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010900* -- Coal
Lignite
& Peat-- Environmental Aspects
ACID MINE DRAINAGE
BACTERIA
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
COAL MINES
ELEMENTS
FLUIDS
GASES
LAND RECLAMATION
MATHEMATICAL MODELS
MATHEMATICS
MICROORGANISMS
MINES
MINING
NONMETALS
NUMERICAL ANALYSIS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
SPOIL BANKS
SURFACE MINING
TEMPERATURE MEASUREMENT
UNDERGROUND FACILITIES