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o ~ ~ r..:J condensed out of the product fuel process lines. This water is derived from the hydrogenation of oxygen in the coal, from moisture in the coal, and from unreacted steam put through the coal conversion reactor. The condensate flow rates are relatively large, show a wide variation, and 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 since a circulating cooling system can acc~pt consid- erably more organic material and ammonia than would be permissible for discharge to a river. However, the cooling tower blowdown then becomes the principal discharge point for the whole plant and this blowdown will contain, in addition to concentrated salts, residues of organic matter originating in the coal reactor. There are a number of ways in which the blowdown streams from boiler feedwater treatment and and cooling towers could be disposed of. Im- poundment in lined evaporation ponds is perhaps the most probably method. Another method is to wet down the coal ash with the concentrated blow- downs. 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. In terms of costs, it is estimated that wastewater control for a coal gasification plant would run, 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 by $3-4 per million Btu. Surface Retorting of Oil Shale. Two different water management schemes were analyzed for: an oil shale convension complex in which surface <retort- ing occurs. In one scheme, the processed shale is moisturized, transported to the disposal sire, and compacted. The spent shale is moisturized with all of the wastewaters generated in the plant, and then some. Thus, the only treatment that would be required would be to remove odorous, volatile substances, which is standard practice. The cost of this treatment is est- imated to range anywhere from about 1 to3 cents per million Btu of product. In the second scheme, a valley would be lined with a thin, impermeable 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 compaction purposes, retorting and upgrading wastewater would have to be treated for recycle 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. cxxiv