AWWA JAW69265

Accurate and representative measure of treatment system performance in removing Cryptosporidium depends on the nature of the surrogate. This research was undertaken to assess the performance of two point-of-use (POU) systems in removing microbial contaminants and to evaluate appropriate surrogates for Cryptosporidium removal in POU systems with charged media. The POU devices tested achieved virtually complete removal of microbial contaminants and satisfied the U.S. Environmental Protection Agency requirements of microbial purifiers for Escherichia coli and viruses. In addition, results showed that Bacillus subtilis spores were a more reasonable and effective conservative surrogate for Cryptosporidium removal than were polystyrene latex beads for separation systems that function predominantly on charge mechanisms. Furthermore, the spores offer the advantages of being easy to separate and quantify. Given the expensive and time-consuming analytical techniques for Cryptosporidium, utility managers will want to select the most appropriate surrogates to evaluate the performance of treatment systems. Includes 39 references, tables.