CHARLESTON, W.Va. -- Officials at Charleston's Sanitary Board don't expect the pollutant levels to rise at their treatment plant because of contaminated water from last week's "Crude MCHM" spill into the Elk River.The board's water flow is up to about 20 million gallons a day, more than twice its normal level, according to operations manager Tim Haapala.The system is getting diluted water because the flushing process West Virginia American Water implemented Monday. Rain from the weekend is also increasing dilution and flow rates in the city's storm-sewer system, Haapala said."What we're getting in is a fairly low-strength waste load," Haapala said.Crude MCHM is nothing the board tests for, but Haapala said because it is a methanol-based chemical, the treatment facility's biomass -- or, bacteria used to consume organic matter in sewer water -- uses it as a carbon source.
"We, with a high level of oxygen, can oxidize materials that some other municipal plants can't," Haapala said.In general, the board must remove 85 percent of total suspended solids and measure how much oxygen is needed to break down organic matter (called "biochemical oxygen demand") as part of its treatment process."The Sanitary Board runs at about 93 to 95 percent removal," Haapala said.The sanitary board doesn't treat water for consumption. Once its intake goes through a separation and disinfection process, it is released into the Kanawha River.The board is submitting water samples to the state Department of Environmental Protection for testing. It routinely submits data on its pollutant output to the DEP, Haapala said.Reach Rachel Molenda at firstname.lastname@example.org or 304-348-5102.