AWWA ACE70572

This powerpoint presentation begins by providing a brief overview of biological perchlorate reduction and molecular biology tools (MBTs) for treatment processes. Research objectives included: develop quantitative assay targeting perchlorate-reduction gene; examine relationship between perchlorate removal and gene expression levels; and, apply qPCR and RT-qPCR assays to perchlorate treatment bioreactor. Research tasks included: development of quantitative molecular assays for perchlorate treatment; and, application of assays to a bioreactor. Conclusions indicated that: qPCR and RT-qPCR assays provide an additional line of evidence that microbial perchlorate reduction was occurring in the bioreactor; cld gene copy numbers generally were higher when perchlorate removal was higher; cld gene transcript copy numbers generally were higher when perchlorate removal was higher; when bioreactor performance declined, gene copies and gene transcript copies also declined; and, bioreactor failure may be explained, at least in part, by changes in the microbial community. Includes figures.