CLARKSVILLE, TN (CLARKSVILLE NOW) – The city’s wastewater treatment plant is one step closer to a $40 million upgrade, one that should end the seasonal stench coming from the landfill in Woodlawn.
The project will receive $15 million in funding from the America’s Rescue Plan Act.
“This grant will allow for significant infrastructure upgrades that will benefit residents and businesses throughout the community,” said state Sen. Bill Powers in announcing the grant.
The big project: Thermal dryers
The grant will help pay for a new six-story building that will contain thermal dryers to be built at the current wastewater treatment facility, according to Mark Riggins, general manager of Clarksville Gas & Water.
Thermal dryers dry residual sludge — a byproduct of the water treatment plant’s cleaning process — making it easier to dispose of properly in ways other than just dumping it in a landfill, Riggins said.
Rhonda Fulton, marketing coordinator for Gas & Water, described the heat dryer process.
“The dewatered waste sludge is folded into a rotary drum with an additional heat source to dry the sludge even further to create a Class A biosolid. It will then be pelletized to create a product that is easier to handle,” he said.
After the sludge is removed for treatment, the treated liquid is discharged into the Cumberland River, and this has been the practice since the beginning. For those concerned about the river’s health, Riggins said treated sewage is cleaner than drinking water.
The remaining sludge has been sent to the Bi-County Landfill. “Solids themselves, they’re treated and there (are) different ways you can treat them and then dispose of them,” Riggins said.
Before the 2010 flood, crews at the Wastewater Treatment Plant were processing sludge into a grade that could be applied to land. “And people use it as fertilizer,” Riggins said. “We moved it out there to a farm, or something like that, that they wanted, and then we had a … manure spreader that people could load into it and then spread on their farms.”
According to epa.gov, the end product of sewage treatment plants is often a Class A humus-like material with no detectable levels of pathogens that can be applied as a soil conditioner and fertilizer to gardens, food and forage crops.
But Riggins said the flood caused major damage to the sewage plant, and returning to the fertilizer-making process would be expensive. “This sludge… is (called) a biosolid, it is currently being landfilled and disposed of.
“Now, then, when that decision was made, the landfill was willing and happy to do it,” he said.
But in recent years, the smell has become a problem. “There (are) a lot of complaints (from nearby neighbors) about the smell at the landfill,” Riggins said.
Mark Neblett, executive director for the Bi-County Solid Waste Management System, said they get about five loads of sludge a day and it smells really bad.
“The other problem is that it’s hard to mix it with the other waste to compact it,” Neblett said, noting that if there’s too much sludge mixed in with regular waste, it creates a sort of quicksand, causing heavy equipment to stick. . .
Long term solution
When looking for a solution, Riggins said a consultant suggested Gas & Water move the sludge to a different landfill, at a cost of $15 million.
“I just felt it was a waste of ratepayers’ money,” he said. “If I’m going to spend $15 million, I want it to be something that will work for this plant for eternity.”
Riggins said that with the new thermal dryers, production will be reduced by up to 70% and the process will allow the sludge to be re-graded for use as fertilizer for farmers.
“We are grateful to the Tennessee State Department of Environment and Conservation for their approval of our grant application,” said Clarksville Mayor Joe Pitts. “The funding will help resolve a long-standing issue at our wastewater treatment plant. Credit to Mark Riggins and our family of CGW employees for their work in securing these funds.”
The next step is to put the project out to bid, and the project should be completed in about two years, Riggins said.