222 



BIRGE 



TABLE 1 



COAL TRACE ELEMENTS SELECTED 

 FOR BIO ASSAY EVALUATIONS 



*The majority of values are from Ruch, 

 Gluskoter, and Shimp (1974), Fulkerson et al. 

 (1975), and Carter (1975) and represent means for 

 multiple coal samples taken largely from western 

 Kentucky and southern Illinois. Lower means for 

 Ag, Tl, Sn, and W are from Lloyd (1976), and the 

 upper mean for Ag is from Vaughan et al, (1975). 



liter/hr, giving a detention time of 42 hr. Water was discharged from 

 the settling chamber into an overflow-equipped effluent reservoir. 

 The ash-to-water ratio and the detention time were calculated to 

 approach conditions observed for a local ash-settling pond (Freeman 

 and Birge, 1978). Also, the detention time was in good agreement 

 with times reported for a number of TVA ash ponds (Chu, Ruane, 

 and Steiner, 1976). Influent and effluent water samples were taken 

 at 1- to 2-day intervals for 2000 hr of continuous operation to 

 observe changes in water-quality parameters. Determinations were 

 made on pH, conductivity, alkalinity, and total dissolved solids, and 



