Part of that corrective action was already in the works when the city was issued the director’s order on Dec. 13 by the Tennessee Department of Environment and Conservation’s Division of Water Resources.
Water Superintendent Bill Pearson has been drafting bid specifications to rehab the city’s six water tanks, and on Tuesday the Board of Mayor and Aldermen agreed to advertise for bids.
That project will include cleaning the tanks and installing mixers and aeration systems in certain tanks.
The BMA also voted Tuesday to approve a $15,336 one year “service support” contract with the manufacturer of the city’s Miex water filtration system. The city will also pay $100 per hour if an engineer is needed.
Pearson said the manufacturer will help make the system more efficient and reduce disinfectant byproduct.
What does the TDEC order say?
Rogersville is required to pay $1,424 of the $7,120 fine by Jan. 31, and exemption from the rest of the fine is contingent on future compliance.
That compliance includes providing the state with a plan for a 180-day distribution system optimization study that characterizes water quality in relation to disinfection byproducts.
After the study is completed, Rogersville must submit a CAP (corrective action plan) and implement it within one year of its approval by the state.
You can view the entire TDEC order in the photo gallery of the online version of this article at www.timesnews.net.
What are disinfection byproducts?
Disinfection byproducts can form when water treatment disinfectants, such as chlorine, react with naturally present compounds in water.
Rogersville’s fine is the result of exceeding the state limit for TTHM (total trihalomethanes) in the first, second and third quarters of 2018 as well as exceeding HAA5 (haloacetic acids) in the first, second and third quarters of 2016.
TTHMs are the result of a reaction between the chlorine used for disinfecting tap water and natural organic matter in the water. At elevated levels, TTHMs have been associated with negative health effects such as cancer and adverse reproductive outcomes.
Haloacetic acids are chemicals that can form as a result of water treatment when water acidity and temperature are slightly high and treatment chemicals react with organic particles or bromide.
Some people who drink water with high levels of HAA5s over time may have a higher risk of cancer and/or reproductive problems.
Only slightly over the limit
“We were very close,” Pearson told the BMA Tuesday. “We missed being in compliance by 0.35 (mg/l) front end average. ... So, we’ve made improvements, and we’ve got to continue making improvements. The things I’ve been talking to you about — tank rehab and managing the MIEX (filtration) system to get the best efficiency — will help.”
Pearson said he believes part of the problem is the city has too much reserve water.
“The study will evaluate water age, it will evaluate turnover and mixing,” Pearson said. “We’ve got more volume than we actually need. We’re required to have a 24 hour supply for fire protection, but in reality we’ve got more than that. We’ve got six tanks. Five of them are older. ... The tank rehab includes mixing and aeration. That tank rehab will play right into this.”
The engineering firm of Vaughan and Melton is in the process of creating a proposal and plan to conduct the study and is expected to make a presentation to the BMA next month.
That study will include creating a model of the Rogersville water system to show how water flows through and how it is turned over. Pearson said the system is currently undergoing a flushing program which has helped reduce disinfectant byproducts.
“Without turnover in your tanks, you’re going to have disinfected byproducts,” he added.