By Brian Wheeler
Thursday, July 19, 2012
Now at least one of its members has come to the conclusion that avoiding chloramines may help maintain public confidence in the water supply.
County resident May Liao started the conversation by encouraging the ACSA to give further scrutiny to the costs of one of the chloramines alternatives, granular activated carbon.
“It really seems like the only reason that people are doing this is for costs,” Liao said about the Rivanna Water & Sewer Authority’s plan to use chloramines. “We have been working with … Integrated Resource Management, which suggests that Hazen & Sawyer’s numbers are greatly inflated.”
Hazen & Sawyer is the lead consultant working for the RWSA and California-based Integrated Resource Management’s Robert W. Bowcock participated in the June safe water symposium hosted by the authority.
“It would be great if we could get a further breakdown of how Hazen & Sawyer came up with those numbers,” Liao added. “Just as when you are remodeling a house, maybe we could get a third-party bid and not just trust this number that they are giving.”
In February, the RWSA approved a $5 million capital project to put chloramines in public water as a secondary disinfectant. Chlorine is and will remain the primary disinfectant. Chloramines was determined to be more cost effective than alternatives like GAC, which was estimated to cost $18.3 million.
RWSA executive director Thomas L. Frederick Jr. says the cost estimate for carbon filtration is based on the urban water treatment plants running 365 days a year at their full treatment capacity.
Chloramines are created by combining chlorine and ammonia and are intended to prevent pathogens from growing within the water distribution system. The RWSA says a new treatment approach is necessary to meet standards set by the Environmental Protection Agency.