By Melanie Addington/The Oxford Eagle
OXFORD – It may not be pretty, but it might as well be a little more green.
Sludge from the former wastewater treatment plant lagoon may soon have a new job — feeding crops.
The Oxford Board of Aldermen recently approved for Burle Engineering services to move the sludge from the lagoon onto the fields of Briscoe and Sons Farm. Now the city must wait for approval from the Mississippi Department of Environmental quality for its biosoilds land application.
Sludge, or biosolids, is the semi-solid remains of sewage treatment processes and has been commonly recycled as fertilizer in Europe. According to the United States Environmental Protection Agency (EPA), biosolids that meet treatment and pollutant content criteria “can be safely recycled and applied as fertilizer to sustainably improve and maintain productive soils and stimulate plant growth.”
The MDEQ can either approve the sludge to be spread across the fields at one time or over two to three years.
When the upgrades to the plant were made, the city went from holding 3.5 million gallons of wastewater to 6.5 million a day, but had to build a new lagoon for sludge and overflow.
“We had an existing lagoon at the plant which was constructed in the early ’90s, but it had reached its life span,” City Engineer Bart Robinson said. “We don’t want to lose it as a lagoon, but since we have the new one, we have time to rehabilitate and eventually be able to use it again.”
Robinson said the city explored several options. The traditional way is to drain the lagoon and dry the sludge before hauling it off. The other option is to apply it to farm fields as fertilizer.
“We got to looking at that option and knew we would like to do it,” Robinson said. “It is the environmentally sound way to do it.”
The benefit of going green is that the alternative also costs less. A ballpark estimate, Robinson said, is around $500,000 whereas drying the sludge and hauling it would cost close to $800,000.
The one struggle to recycle the waste in Lafayette County are the regulations on the type of fields that are allowed. With not as many crop fields in the area, Robinson said it was challenging to find the right size field that has a certain amount of buffer between creeks, rivers and residences.
“This limits to two or three sites in Lafayette County,” Robinson said.