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Assessment of the Effects of Holding Time on Fecal Coliform and Salmonella Concentrations in Biosolids

The purpose of this study was to determine whether biosolid samples can be held for 24 hours without significant change in bacterial densities for these analytes. This report presents the result of biosolids holding time study of most probable number (MPN) procedures for the analysis of fecal coliform (using EPA Methods 1680 and 1681) concentrations in Class A and Class B matrices and Salmonella (using EPA Method 1682) concentrations in Class A matrices. 

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