SOIL AMENDMENTS PROMOTE VEGETATION ESTABLISHMENT AND CONTROL ACIDITY IN COAL COMBUSTION WASTE
R.M. Danker1, D.C. Adriano1, Bon-Jun Koo1
, C.D. Barton2, and T. Punshon1,3
1 Advanced Analytical Center for Environmental Sciences, The
University of Georgia, Savannah River Ecology Laboratory, Drawer E, Aiken,
SC 29802
USA
2 USDA Forest Service, Center for Forested Wetlands Research
c/o Savannah River, Ecology Laboratory, Drawer E, Aiken, SC 29802, USA
3 Rutgers University, Division of Life Sciences, 604 Allison
Road Piscataway, NJ 08854, USA
1. ABSTRACT
The
effects of adding various soil amendments and a pyrite oxidation inl1ibitor
to aid in the establishment of vegetation and to reduce acid drainage
(AD) from coal fly ash and coal reject (FA + CR*) were assessed in an
outdoor mesocosm study. Preliminary greenhouse experiments and field observations
at the U.S. Department of Energy's Savannah River Site (SRS) indicated
that plants would not survive in this material without altering its physical
and chemical characteristics. Samples of mixed FA + CR were obtained from
a field site at the SRS. The following treatments were used: Biosolid
only (Treatment A), Biosolid + Surfactant (Treatment B), Topsoil + Surfactant
(Treatment C), and Biosolid + Topsoil + Surfactant (Treatment D). Leaching
was induced due to inadequate rainfall. Loblolly pine seedlings (Pinus
taeda) inoculated with ectomycorrhizal fungi - Pisolithus tinctorius
(Pt) and Sclerodenna cepa (Sc) - were transplanted into each
mesocosm tank. Soil solution samplers were installed in each unit at 15
and 41 cm depths. Samples were taken periodically and measured for pH,
EC, and other parameters. The results indicate that the addition of amendments
can aid in the revegetation of a FA + CR landfill and control AD. Pine
seedlings growing in treatments with biosolid application were significantly
taller than the treatment without it; however, there were no significant
differences concerning diameter, biomass, and plant tissue concentrations
of AI, Fe, and Mn for the pines. Biosolid addition also appears to be
effective for mitigating proton generation. Sodium lauryl sulfate (SLS)
and topsoil addition were not as important to plant survival and growth
as biosolid addition; nonetheless, SLS and topsoil addition did not appear
to be disadvantageous to growth in the treatment with biosolid addition
(Treatment D). Based on leachate data, the-topsoil + surfactant treatment
had a much lower initial pH (pH -3 or below) than the other treatments,
and AI concentrations were correspondingly high. Electrical conductivity,
in general, has been decreasing since the inseption of the study and appears
to indicate that the addition of biosolid+ surfactant (Treatment B) is
the most effective treatment for inducing the lowest sulfate and metal
concentrations. Preliminary results that the use of amendments is essential
for plant growth and establishment in pyrite enriched coal waste sites.
SREL Reprint #2750
Danker, R. M., D. C. Adriano, Bon-Jun Koo, C. D. Barton and T. Punshon. 2003. Soil amendments promote vegetation establishment and control acidity in coal combustion waste. p. 319-333. In Chemisty of Trace Elements in Fly Ash, edited by K. S. Sajwan, A. K. Alva and R. F. Keefer. Kluwer Academic/Plenum Publishers.
