Role of lime in salty spoil genesis
Acid pyritic spoils are often limed to facilitate revegetation efforts. Substantial quantities of soluble sulfate salts are associated with such spoils, before and after liming. Such salts can cause revegetation attempts to fail at seeding and/or during drought stress periods. As magnesium sulfate (MgSO/sub 4/) is more soluble than gypsum (calcium sulfate) under field conditions, MgSO/sub 4/ has more often been associated with soluble salt problems. Since lime reaction chemistry can influence salt genesis in spoils, this was evaluated in a incubation study using calcite and dolomite amendments to an acid, pyritic spoil. Rates of 0, 14.4, and 28.8 meq/100 g (rate equal to total potential acidity) of lime were used. Amended spoils were maintained at 30/sup 0/C and -100 cm moisture tension. Samples were taken periodically and a portion suspended in water at a soil:solution ratio of 1:20 for two hours. Unamended spoil extract pH dropped from 4.8 to 3.2 in nine weeks. Soluble magnesium sulfate doubled (from 2.9 to 6.1 meq/100 g) in the unlimed spoil between weeks one and sixteen. Dolomite amended spoils generated twice as much magnesium salt as calcite amended spoils. Pyrite oxidation, acid generation, i.e., salt genesis, was reduced when calcitic lime was used at the recommended rate based on a measure of total potential acidity. A prompt liming program with calcitic lime can substantially alter the quantity and quality of soluble salts released. The results suggest that dolomite is unacceptable as a liming material for sandy spoils with an appreciable pyrite content.
- Research Organization:
- Univ. of Kentucky, Lexington
- OSTI ID:
- 5305730
- Report Number(s):
- CONF-821175-
- Journal Information:
- Univ. Ky., Off. Eng. Serv., (Bull.); (United States), Conference: Symposium on surface mining hydrology, sedimentology, and reclamation, Lexington, KY, USA, 1 Nov 1982
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
01 COAL, LIGNITE, AND PEAT
SPOIL BANKS
LIMING
REVEGETATION
SALT DEPOSITS
SURFACE MINING
LAND RECLAMATION
DOLOMITE
LIMESTONE
MINING
PLANT GROWTH
PRECIPITATION
PYRITE
ALKALINE EARTH METAL COMPOUNDS
CALCIUM CARBONATES
CALCIUM COMPOUNDS
CARBON COMPOUNDS
CARBONATE MINERALS
CARBONATE ROCKS
CARBONATES
CHALCOGENIDES
GEOLOGIC DEPOSITS
GROWTH
IRON COMPOUNDS
IRON SULFIDES
MAGNESIUM CARBONATES
MAGNESIUM COMPOUNDS
MINERALS
OXYGEN COMPOUNDS
ROCKS
SEDIMENTARY ROCKS
SEPARATION PROCESSES
SULFIDE MINERALS
SULFIDES
SULFUR COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
510500* - Environment
Terrestrial- Site Resource & Use Studies- (-1989)
010800 - Coal
Lignite
& Peat- Waste Management