"This paper provides a preliminary process design and cost estimate for a 56.8 MWe pilot plant utilizing the linked vertical wells process for the underground gasification of coal. The pilot plant is assumed to be located on a coal seam which is similar to that at the Hanna Field. A base case process design indicates that the pilot plant will require 10 simultaneously producing wells. The total area gasified in a 2-year operating period will be 7.5 hectares. During the first year, 90 wells will be required, and 80 wels will be needed in the second year. The gas produced will be subjected to the operations of particulate removal, quenching and condensables separation, and desulfurization before being used for power production. In this design, the power plant consists of a split stream system with a conventional boiler based steam cycle and a low-Btu gas turbine. An evaluation of the costs indicated that a fixed capital outlay of about $70 million is required for a 56.8-MWe pilot plant. Calculation of the capital costs at other capacities reveals that a capacity factor of 0.71 is applicable to the system. The necessary capital cost shows only a very small decrease with an increase in the heating value of the gas to be produced."