detrimental to surface water quality if allowed to reach a stream,            W
lake or impoundment.

It appears that production of many of the contaminants present in
yard waste compost leachate could be lessened or eliminated by
actively managing the compost to allow the waste to decompose under
aerobic conditions. However, further studies are needed to determine
the ground water impacts and leachate quality of unlined composting
facilities that encourage aerobic decomposition.

Further studies are also needed to determine whether or not lining of
yard waste compost sites can mitigate all potential ground water
contamination problems from large sites that allow anaerobic
decomposition to predominate. This study examined one site, Site A,
that was sited on a clay deposit and found that the clay did not
prevent the ground water quality from being significantly impacted.
The leachate results from Sites A and D would seem to indicate that
the presence of a clay layer beneath sites that allow large, seldom
turned static piles may actually promote anaerobic decomposition by
keeping the wastes saturated for longer periods of time.


                              References

Cole, Michael A., 1994, "Assessing the Impact of Composting Yard
      Trimmings"; Biocycle, April, 1994, pp. 92-96.

Helfrich, John, 1992, "An Examination of the Chemical Characteristics
      of Yard Waste Compost Leachate"; Project No. YWLH 510, Waste
      Management, Inc., April 1992.

Hem, John D., 1992, "Study and Interpretation of the Chemical
      Characteristics of Natural Water"; U.S.G.S. Water-Supply Paper-
      2254, Third Ed., 1992.

Kee, N.S. and Bloomfield, C., 1962, "The Effect of Flooding and
      Aeration on the Mobility of Certain Trace Elements in Soils";
      Plant and Soil, 1962, vol. 16, pp. 108-135.

Kovacic, David A., Cahill, Richard A., and Bicki, Thomas J., 1992,
      "Compost: Brown Gold or Toxic Trouble?"; Environ. Sci. Tech.,
      1992, vol. 26, no. 1.

Richard, Tom and Chadsey, Matt, 1990, "Environmental Impact of Yard
      Waste Composting"; Biocycle, 1990, vol. 31, no. 4, pp. 42-46.

Strom, P.F. and Finstein, M.S., 1986,"LaCopsigPjet                Fnl
      Report"; submitted to the N.J. Dept. of Energy and Envir.
      Protection, Newark, N.J., 1986.

Varsa, Steve R., 1994, "Potential for Groundwater Contamination from
      Yard Waste Composting Operations in Illinois"; Master' s Thesis,
      S.I.U. -Carbondale, Dept. of Geology, April, 1994.0