ENVIRONMENTAL IMPLICATIONS 161 



from coal. These are also the three major factors in the production of 

 potentially hazardous organic substances during the conversion 

 process. The products of coal liquefaction can be used directly as 

 boiler fuel in stationary power-generating stations or upgraded and 

 refined for use as gasoline or petroleum feedstock. 



The primary' source of contaminants reaching the aquatic 

 environment will be aqueous effluents, which will be enriched in 

 organic compounds through the process of product hydrotreating 

 (Fig. 2). Leachates arising from the ultimate disposal of solid wastes 

 can also contaminate water (Gehrs, 1978), as can accidental spills 

 and disruption of plant operation. 



No large-scale coal-conversion facilities currently exist in the 

 United States, and the smaller units that are now operating do so 

 intermittently (and, thus, have atypical effluents) with no or little 

 waste treatment. Although these facts pose problems for ecologists 

 attempting to determine potential contamination from coal con- 

 version, there is also a unique opportunity to aid in developing an 

 environmentally acceptable technology(ies) if the ecologist produces 

 relevant, timely data. 



HISTORIC DATA ON EIMVIROIMMEIMTAL 

 HAZARDS OF COAL CONVERSION 



Although no large coal-conversion facilities are presently 

 operating in the United States, Union Carbide operated a 

 300-ton/day experimental facility at Institute, W. V., in the early 

 1950s. The results of this experiment, which included both medical 

 observations and animal testing, are reported in a series of papers by 

 Sexton (1960) and Weil and Condra (1960). They suggest the need 

 for health and environmental concerns related to coal conversion. 

 Despite the use of an aggressive industrial hygiene program, the 

 incidence of skin cancer among the approximately 364 workers was 

 between 16 and 37 times that reported in the general population 

 (Sexton, 1960). 



Whole animal studies on various process and product streams also 

 revealed carcinogenic potential (Weil and Condra, 1960). These 

 results showed that most of the carcinogenic activity was found in 

 the heavy oils (boiling point >260°C). More recently, Bingham 

 (1975) found the products of three liquefaction processes currently 

 under development to be carcinogenic in animals, and Hueper (1956) 

 identified the heavy ends as more active than the light ends. Caution 

 must be taken in interpreting these data, however, since the products 



