SALEM - What to do about sludge - that's what Salem Utilities Commission members have to decide after studying their options for getting rid of the waste material left after the wastewater treatment process.
Sludge disposal options were the topic during a work session of the commission last week, with Assistant Utilities Superintendent Matt Hoopes highlighting them during a powerpoint presentation. The commission took the information under advisement, with Chairman Geoff Goll saying the options need more study and they need to look at what's really needed.
The city does not have sludge storage at the wastewater treatment plant and contracts with Synagro to dewater and transport the sludge from the facility. Dewatering is the process used to remove as much moisture as possible from the solids.
When possible, the sludge is applied to agricultural lands, but at times when that's not permitted due to moisture conditions of the land, the material must be transported to an Ohio Environmental Protection Agency-approved landfill. The landfill being used for the city's sludge had been located in Alliance, but the landfill closed in June, with the closest alternative twice the distance away near the Pennsylvania border in Lowellville.
The commission members were told in June that using the new landfill site would increase the cost of hauling the sludge away by $197,000 over the remaining 17 months of the Synagro contract, due to increased transportation costs and increased tipping fees. Utilities Superintendent Don Weingart suggested the commission look into constructing a sludge storage pad onsite which could hold sludge until it could be applied to farm fields instead of having to go to a landfill.
Burgess and Niple Inc. provided the commission with an estimate of $448,300 for construction of a 100 feet by 100 feet storage pad with 6-foot high kick walls at the wastewater treatment plant on Pennsylvania Avenue. At present conditions, with Synagro still doing some dewatering, the capacity would be about 75 days. After planned improvements to the wastewater treatment plant, the capacity would increase to about 251 days. The total cost for the pad, dewatering and land applying totaled $654,944.
At the August meeting, Goll had asked the department to look at the cost of buying trucks so the city could haul the sludge to a landfill using city employees. The cost was estimated at $224,990 for the truck and semi tractor and two dump trailers from MAC Trailer, with an additional $206,944 to use Synagro for dewatering and $88,192 per year to hire an additional employee dedicated to sludge removal with a Class A commercial driver license for a total cost of around $535,000.
Another option would be to landfill all of the sludge, with Synagro doing the transportation at a cost of $397,317.
Both the truck option and the storage pad option include capital costs which wouldn't always be there.
Commission member Primo Citino asked if anyone had looked at what other communities are doing and what it costs them. Goll questioned if the city was transporting the sludge, whether the city could take advantage of its size and maybe offer transportation services to other communities to haul their sludge.
Hoopes said he thought having a storage pad with permanent dewatering onsite through wastewater treatment plant improvements was the best option for the facility longterm.
"We're having a real hard time spending half a million dollars for a piece of concrete," Goll said about the storage pad, with commission member Bob Hodgson adding,"It seems like an awful lot of money."
Goll said they needed more time to study the options, noting, "this isn't being done lightly."
Mary Ann Greier can be reached at firstname.lastname@example.org