Chemical and toxicological properties of coal fly ash - University of ...

Table 24. The range of concentrations and recommended water quality levels for chemical constituents measuredin test solutions of 17.Range ofRecommended waterChemical concentrations qua1 i ty levels r2constituent (mdL) a (md~) ChangeC YCaAl 1 values in mg/L except pH.b~alues are MATES cited from Cl eland and Kingsbury (1977) unless another source isindicated.CValues o f r2 and r represent the results from mu1 tiple and simple 1 inearregression analyses of the relationship between mortality observed in the testsolutions of the extract and the concentrations of each chemical constituent measuredin those test solutions.d~rorn Quality Criteria for Water 1976 (U.S. EPA, 1976).96-hour LC-50s for Zn for steelhead trout varied, depending on whichlife stage was exposed. Mount (1966) found an inverse relationship betweenZn toxicity and water hardness for fathead minnows. Mount tested the acutetoxicity of Zn under various pH and hardness conditions, making directcorrelations of Zn and toxicity difficult. Using hard (200 mg/L asCaC03) and alkaline (nominal pH = 8.0) dilution water, the LC-50 wasapproximately 8.2 mg/L of Zn. These data suggest that Zn might be partlyresponsible for the mortality caused by I7 test solutions.Sulfate and other ions were present in relatively high concentrations,contributing to the electrical conductivity (EC) , whic varied between 4.1and 5.29 mmhos/crn (Table 16) in the undiluted extract of 17. Significantmortality of fathead minnow fry has been observed in reconstituted water in