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~ ~ ~ ~ process lines. This water may contain large quantities of ammonia, carbon dioxide, phenols, and other organics. In most conversion processes, the condensate wastewater is so contam- inated that its release to the environment in any form is unacceptable. Therefore, it is likely that treated condensate will be used as make-up to a cooling tower. The cooling tower blowdown then becomes the principal discharge point for the whole plant. This blowdown will contain, in addi- tion to concentrated salts, residues of organic matter originating in the coal reactor. There are a number of ways to dispose of the blowdown streams from boiler feedwater treatment and cooling towers. Impoundment in lined evapo- ration ponds is the most probable method. Another method is to wet dawn the coal ash with the concentrated blowdown. In some instances, the cooling tower blowdown might have to be treated to reduce organic contamination before it could be used to wet down the coal ash. It is estimated that wastewater control for a coal gasification plant would cost (on an annualized basis) anywhere from about 3 to 20 cents per million Btu of product depending upon the particular treatment and disposal options employed and the quality of the waste streams handled. By way of comparison, the total cost of producing a high-Btu pipeline quality gas is estimated to be $3 to $4 per million Btu. Surface Retorting of Oil Shale. Two different water management schemes were analyzed for an oil shale conversion comples in which surface retort- ing occurs. In one scheme, the processed shale is moisturized with all of the wastewaters generated in the plant, and then some. Thus, the only treat- ment that would be required would be to remove odorous, volatile substances The cost of this treatment is estimated to range anywhere from about 1 to 3 cents per million Btu of product. In the second scheme, a valley would be lined with a thin, imperme- able layer of compacted spent shale that is wetted down. The remainder of the spent shale would be deposited into the lined basin and compacted, but not wetted down except for controlling dust. Since this second scheme would require very little water for moisturization purposes, retorting and upgrading wastewaters would have to be treated for recycling and reuse within the plant. In this regard, it was assumed that the wastewater would be treated for use in a cooling tower in a manner similar to that for a coal gasification plant. For this second scheme, the estimated costs (on an annualized basis) of wastewater management would run anywhere from about 1.5~ to 3~ per million Btu of output. By way of comparison, the total cost of producing crude shale oil is estimated to be in the range of at least $2.50 to $3.00 per million Btu. 1-17