12    THERMOPHILIC COMPOSTING OF A SYNTHETIC JP-4
FUEL MIXTURE
Patrick T. McMullen, Research Assistant
Raymond W. Regan, Sr., Associate Professor
Department of Civil Engineering
and the Environmental Resources Research Institute
The Pennsylvania State University
University Park, Pennsylvania   16802
INTRODUCTION
The storage and handling of Jet Propellant number 4 (JP-4) at United States Air Force (USAF)
installations frequently results in the contamination of soil in areas where these activities occur. Once
in the soil the water soluble fraction of JP-4 can be carried by infiltrating rainwater into groundwater
aquifers. Contaminated soils can be excavated for treatment or burial or treated in situ. Conventional
treatment of contaminated soil has been limited primarily to excavating prior to landfilling or incineration. Both alternatives are extremely expensive and have limited availability. During the last few
years composting has been evaluated by both private and Department of Defense groups as an
alternative for treating soil contaminated with various organics.'3 These preliminary studies show
considerable promise. A major incentive to pursuing this work is that composting is believed to be
comparatively inexpensive compared to other alternative approaches and can be accomplished with
commonly available materials.
PROGRAM
The goal of this concept evaluation study was to treat soil contaminated with a simulated jet fuel
mixture in an active compost and to monitor the fate of the fuel mixture. The compost was a mixture
of straw and animal manure and the synthetic fuel a mixture of benzene, ethylbenzene, nonane,
methyl napthalene and tetradecane combined in a volume ratio of 62.5% aliphatic and 37.5% aromatic components. Soil contaminated with fuel mixture was added to the compost to achieve the
following total hydrocarbon concentrations: 3,000 ppm, 30,000 ppm, 300,000 ppm and 600,000 ppm
(on an ash basis). Each compost reactor was held in a hot water bath at 55°C for 42 days. C02
generation and fuel component removal were monitored during this period. In a separate phase of the
project, the volatilization of fuel components from the compost was measured.
BACKGROUND
The problem of fuel and other petroleum distillate contaminated soil is widespread. The major
concern is usually the secondary contamination of groundwater resulting from the leaching of hazardous materials. Requirements vary for treating contaminated soil. California and South Carolina have
well defined criteria for determining when contamination is a problem and have been active in
ensuring the problem is corrected. Other states are far more lenient.
Often the remediation response consists of allowing the soil to remain in place with an impervious
cap to prevent leaching. This is a temporary solution but one employed by the US Air Force (USAF)
in several instances. It can be effective so long as the water table is well below the depth of contamination. Selection of a temporary solution is driven at times by economic considerations. The entire fiscal
year 1987 budget for treating all hazardous waste at USAF sites was approximately $30 million. The
cost for landfilling contaminated soil runs between $5,000-$15,000/m3.4 At these rates, the clean up
cost for a single 200 square meter site, one meter deep would exceed $400 million or 13 times an entire
yearly budget. Incineration is somewhat less expensive but the availability of incinerators is limited.
Other methods such as stripping, chemical oxidation and immobilization have been identified as
technically feasible but are not used due to limited experience in the field and sketchy cost estimates.
At present, the USAF is not landfilling any contaminated soil sites and is using a mobile rotary kiln
46th Purdue Industrial Waste Conference Proceedings, 1992 Lewis Publishers, Inc., Chelsea, Michigan 48118.
Primed in U.S.A.
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