SurfMin: leachate

 

 

 

 

 

OSM Library Number:  570                        Date to NTIS:  06/13/90

NTIS Accession No:  PB90-233149/AS              NTIS List Price:  39.00

CFR Citation:  30 CFR 816.83

 

Title of Report:

 

CHARACTERIZATION OF LEACHATE FROM ABANDONED COAL REFUSE (1987). 3124 pp.

 

Performing Organization Name and Address: 

 

     Western Research Institute, Laramie, WY 82071

 

Type of Report:  Final Report

 

Abstract: 

 

Report derived from considering complete universe of what may be predicted to be

present in coal and/or coal refuse, applying fundamental theories of leaching

and chemical equilibrium, and considered the 2 parameters believed to affect

nature of coal leachates (pH & reduction) oxidation potential.  Approach gives

an accurate representation of inorganic materials to be found in abandoned coal

refuse leachate.  Discussions on nature of organic material address predicted

impact of volatility, water solubility, biogradation & adsorption on the likely

presence of materials in leachate.

 

Keywords:

 

LEACHATE

ABANDONED COAL REFUSE

HAZARD TO AQUATIC ENVIRONMENT

 

Author(s): 

 

Essington, M.E.

Hill, S.L.

Jackson, L.P.

Koesters, D.B.

Mason, G.M.

Spackman, L.K.

Sullivan, P.J.

 

 

 

 

 

 

 

NTIS Accession No:                              NTIS List Price:

 

Title of Report:

 

THE INFLUENCE OF FLY ASH ADDITIONS ON ACID MINE DRAINAGE PRODUCTION FROM COARSE

COAL REFUSE (March 1996) 205pp.

 

Performing Organization Name and Address:

 

Virginia Polytechnic Institute and State University

 

Type of Report:    Doctor of Philosophy Dissertation

 

Abstract:

 

The exclusion of coal fly ash from regulation as a hazardous waste has led to

increased interest in returning ash to the coalfields for disposal. 

Bulk-blending alkaline fly ash with acid forming coal refuse may present a

disposal option that aids in the control of acid mine drainage. A preliminary

column leaching study examined the leachate quality from acid-forming coal

refuse: fly ash blends.  Coal refuse (2.2% total-S), and two refuse:fly ash

blends (20% and 33% ash w/w) were packed into leaching columns and leached under

unsaturated conditions for over four years.  The coal refuse columns acidified

quickly, producing peak leachate levels of acidity (pH 1.7), Fe (10,000 mg 1-1),

SO4-2 (30,000 mg1-1), and Mn (300 mg 1-1).  Both ash blended treatments provided

alkaline leachate with low metal levels.  A second column study used a refuse

with higher potential acidity (4% total-S), and two alkaline ash sources; one

blended at two rates (20% and 33%) and one at four rates (5%, 10%, 20%, and

33%).  Bulk-blended ground agricultural limestone, rock phosphate ore, and

topsoil treatments were also studied.  The unamended refuse treatment acidified

rapidly and produced acidic (pH 1.7) leachates with high peak dissolved metal

levels (>15,000 mg 1-1 Fe; 200 mg 1-1 Mn).  Treatments blended with 33% ash

produced alkaline (pH >8.4) leachates with low metal levels (Al<1.0 mg 1-1;

Cu-0.10 mg 1-1; Fe<2.0 mg 1-1; Mn<3.0 mg 1-1).  Treatments containing less ash

eventually acidified and ash bound metals (Mn and Cu) were stripped from the ash

and eluted in quantities proportionate to the amount of ash in the blend.  A

field experiment with water sampling lysimeters examined bulk-blended refuse

(0.8% S) with two acidic and one alkaline ash.  The ash treatments did not

produce consistent negative impacts on leachate water quality, and produced

positive effects on plant biomass production compared to unamended controls. 

Overall, the inhibition of pyrite oxidation by high ash blends was attributed to

alkalinity effects, chemisorption, decreased hydraulic conductivity, and

decreased oxygen diffusion to pyritic surfaces.  Ash alkalinity and refuse

potential acidity must be balanced for environmental safety in this co-disposal

environment.

 

Keywords:

Coal refuse, leachates, water quality, and plant growth

 

Author(s)

Barry Robert Stewart