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The feasibility of converting a boiler to burn RDF is sensitive to site specific factors such as:' the location of the unit with respect to the waste sypply; the remaining life of the boiler; extent of modifications required; and availability of space for ash handling, waste storage and air emissions equipment. Pyrolysis Refuse pyrolysis is a thermo-chemical process for the conversion of waste into a usable fuel product: The primary by-products of the process are combustible gases or liquids, solid residues and a wastewater effluent. The composition of the waste input and the process conditions activate the various ratios of gaseous, liquid and solid products produced. The waste- water effluent normally contains a high percentage of soluble organic mate- rial and requires on-site treatment or disposal in a sewer. Solid residues vary in composition as a function of the process design producing granular residues composed of inorganic constituents to carbonaceous material similar to charcoal. Application of pyrolytic technologies to refuse is a relatively recent development. Two of the largest refuse pyrolysis projects constructed to date are EPA supported pyrolysis demonstration plants in Baltimore, Maryland and San Diego County, California. The Baltimore facility was designed to process 1,000 tons of refuse daily and recover steam, char, glassy aggregate and magnetic metals. Operation of the plant was initiated in'November 1974. Under the terms of the agreement with the City of Baltimore, the manufacturer was required to provide specific guarantees regarding the system performance. When the plant failed to meet particulate emissions and reliability guarantees, the manufacturer was penalized $4 million. After extensive modifications and attempts to correct the problem, the-manufacturer'declared the demonstration a failure and withdrew from the project in early 1977. The City of Baltimore assumed control of the plant and has performed numerous modifications, includ- ing installation of an electrostatic precipitator, gas purifier and gas discharge stack. The plant has been operated intermittently at a rate of 600 tons per day. While the process appears technically feasible, the EPA has concluded that it is unlikely to compete economically with alternate disposal methods. The San Diego project is a 200 -ton per day waste pyrolysis system designed to convert refuse into a fuel oil. Constructed at a cost of approx- imately $14.5 million, the demonstration plant began operation in August 1977. During the subsequent test program, the longest period the system could be operated on a continuous basis was 37 hours. The oil, which a utility company had agreed to purchase, was of poor quality and sufficient quantities were not produced to allow comprehensive tests. Operation of the plant was suspended in July 1973, because additional substantial expenditures were required to modify the system. The future plans by the process manufacture are unknown and the system is not being marketed on a commercial basis.