Mount Vernon City Engineer said heavy rains on March 25 and 26, 2023, necessitated reinforcement measures at 1700 Old Delaware Road, the temporary storage site for lime material removed from the city's west lagoon last summer. The city and the Ohio Environmental Protection Agency negotiated an agreement which states the city will spend $125,000 each year to remove the material. The OEPA will help the city find alternative uses for the material.
Heavy rain hitting solidified lime material traveled down the spillway to the catch basin at the entrance of the water treatment plant on Saturday, March 25, 2023. This photo, taken March 27, is looking east toward the plant.
That agreement was reached last week, and the Mount Vernon City Council approved it on Monday. It becomes effective once the OEPA signs it.
“The city has agreed that we will spend $125,000 every year to remove the lime from 1700 Old Delaware Road,” Law Director Rob Broeren told Knox Pages on Wednesday. “We have committed to try and have this done by 2025. However, there is a special provision in the agreement to allow us to extend that provision.
“Additionally, the Ohio EPA has agreed to work with us for other potential uses for the lime,” he added.
City Engineer Brian Ball said the city can potentially sell the lime material to companies such as Com-til, which blends the lime material with compost material such as leaves and sticks for beneficial reuse. Selling it would return money to the city's water utility and help offset the cost of removal.
The city began removing lime sludge material — formally known as drinking water treatment material — from its west lagoon in June 2022. The lagoon was full as the city had not removed material from the lagoon for about 40 years.
Additionally, the east lagoon was filling up rapidly, and Tom Marshall, the public utilities director at the time, was concerned the submerged pipe would clog. If that happened, the city would have to shut down the water treatment plant.
The city offered the lime material at no charge to farmers for placement on farm fields. At the same time, the city began removing the material and dumping it at 1700 Old Delaware Road as a temporary storage site. The OEPA ruled the site was not a beneficial use site and in September 2022 ordered the city to begin removing it.
The OEPA's removal timeline was 7,500 cubic yards by Dec. 31, 2022, and another 7,500 cubic yards by Mar. 30, 2023. All material was to be removed by Dec. 30, 2023.
From the City of Mount Vernon, Special to Knox Pages
The city appealed the order.
“Drinking water treatment material is not a hazardous waste,” Broeren said. “We questioned whether the Ohio EPA has the authority to regulate it, as well as the specific timetable for which they wanted us to remove it.”
Ball noted that farmers have 180 days to apply the material, but the material has been in the lagoon — which is not a beneficial use site — for 40 years.
“There was also no rational basis between the amounts they wanted us to remove and when,” Broeren said.
The material can only be applied to fields before planting and after harvesting. It can be delivered during the winter providing the ground is frozen. This past winter did not include much freeze other than around Christmas.
Broeren said the Ohio EPA basically wanted the city to “quarterly remove these amounts” onto farm fields or haul it to a landfill. The cost for landfill was upward of $3 million in tipping fees plus the cost for hauling.
“That was extremely wasteful because of the money and the waste of good material which is very beneficial,” he said. “It was only going to go [to the landfill] because of unrealistic deadlines.”
Broeren said the OEPA agreement will help the city.
“We don't have to have X number of cubic yards removed every three months. We can take a measured approach to setting up a process for long term,” he said.
“That is why time is so significant: It allows us to build relationships and find alternative uses,” he added.
Ball said the agreement gives the city time to determine what permits are needed for non-agricultural uses. Regarding the long-term plan, he said, “Once we're done at 1700, we'll move to the east lagoon for removal. [The $125,000] will be a permanent fixture in the budget.”
Heavy rains on March 25 and 26 necessitated additional measures at 1700 Old Delaware Road.
Overflow from the rain hitting solidified lime material in the north section of the field left lime deposits along the spillway. Straw bales and a sock around the catch basin at the entrance to the plant held back deposits as the water filtered through, but the volume of rain caused water to flow around the bales and the sock.
City crews placed an additional sock at the base of the controlled release point and added more straw bales to provide extra filtration and collection along the spillway. On Monday morning, crews removed lime deposits from around the catch basin.
City workers also placed a siphon in the southern pond to prevent overflowing. Runoff from the siphon goes into a drain that leads to a stormwater retention pond on the east side of the treatment plant.
Runoff going into the catch basin at the plant's entrance also goes to the retention pond. The pond catches lime deposits that get past the straw bales and socks. On Monday, city engineer Ball said there was a trace of lime in the retention pond.