MANSFIELD — The Mansfield Board of Control on Tuesday awarded a $154,000 contract to a Toledo engineering firm to evaluate and suggest improvements to the city’s wastewater treatment plant.
Jones & Henry Engineers Ltd. has worked with the city since 2014 on issues at the 385 S. Illinois Ave. facility, a process that began when the Ohio EPA noted issues at the plant and began requiring improvements.
City engineer Bob Bianchi told the Board of Control the study will help the city find solutions to “revamped” EPA orders at the plant, the final stop for wastewater before it flows back into the Rocky Fork branch of the Mohican River.
Previous improvements at the plant between 2014 and 2018 proved inadequate to meet the EPA’s more stringent permit licensure restrictions approved seven years ago.
“The plant began to routinely exceed the new limits on total suspended solids and (carbonaceous biochemical oxygen demand),” according to an April 15 proposal by Jones & Henry.
CBOD is one of the regulated parameters for polluted water, including for wastewater at wastewater treatment plants, according to the Wastewater Digest online website.
“Occasionally, the plant was able to meet permit limit concentrations. However, due to the high volume of storm water during wet weather, it would exceed the total loading,” Jones & Henry said.
“The city’s permit exceedances have led to significant non-compliance throughout the 2018-2023 permit cycle,” the company said.
Bianchi said Jones & Henry would provide, “an interim study and a more permanent study of what improvements are needed to meet our permit and how we’re going to execute those over time.”
According to Jones & Henry, the Ohio EPA is evaluating revisions to its final findings and orders due to the significant non-compliance.
Bianchi said sewer funds would be used to pay for the study, which would take about a year to complete.
Finance Director Kelly Blankenship asked Bianchi if he knew this would be required and has planned for it.
“I knew we were going to have to do some of the big ticket construction items. I was hoping that we could just award those construction contracts in the next few years, but now the EPA is making us do a more,” he said.
“They want and updated plan (with) a defined schedule,” Bianchi said. “There’s a little bit more work that I did not anticipate in terms of the study.”
After the meeting, Bianchi said he didn’t have a feel for the costs of what improvements may be required.
“We’ve already made a lot of improvements,” he said.
In 2021, for example, the city purchased four new pumps, manufactured by Gorman-Rupp Pumps, for the the Park Avenue East Pump Station, replacing six-decade-old equipment, at a total cost of $4.5 million.
“Our goal is to do whatever we can to make the improvements within the existing (sewer) rate structure that’s set up by (City Council),” he said. “That’s our goal. This study is going to show us all the improvements that are needed.
“The EPA is going to look at it and approve the study, and then we’re going to move forward with design,” he said.
Bianchi said sanitary sewer systems are considered to be separate from stormwater systems.
“But our system is 100-plus-years old. In some locations, groundwater inevitably gets into those pipes. In some older homes, their foundation drains are connected to the sanitary sewer.
“So during a rain event, we get a wave of water to the treatment plant. The treatment plan is a biological process. It takes time to treat a certain amount of flow. When we exceed that flow limit, that’s when we have violations,” the engineer said.
Bianchi said all of the wastewater, even during rainstorms, gets “some level of treatment before it goes to the Rocky Fork. But it’s not full treatment.”