The city of Bowling Green is moving closer to putting into action a plan to control leachate at a closed city-owned landfill in Butler County.
Leachate is contaminated water that has been in contact with garbage.
“It’s a burden for all landfills,” said Matt Powell, environmental manager for the city.
The Butler County landfill is a remnant of when the city operated its own trash collection service. It ceased operation in 1992.
The landfill was shut down because it was reaching capacity and because new, stricter regulations were coming into effect at that time. In 2011, the city entered into a memorandum of agreement with the state in which the state agreed to provide funding for the design of landfill improvements through the Historic Landfill Program.
Plans for phase one of the leachate control project are being finalized, Powell said.
It is expected to go out to bid through the Kentucky Division of Waste Management in November, he said.
Phase one includes the installation of an exposed geomembrane synthetic cap over about 10.8 acres of the landfill to prevent precipitation from reaching the area it covers, Powell said. The cap is a layer of high-density polyethylene plastic.
Similar caps are used frequently in landfills but are usually covered with a layer of dirt to prevent UV damage and movement of the cap, he said. The cap at the Butler County landfill won’t have that covering and is designed to resist UV damage. It should also help to prevent erosion and slope failure of steep areas at the landfill.
Phase one also includes the installation of above-ground tanks to hold leachate that will be pumped up from existing below-ground tanks, Powell said.
Phase one of the project will help reduce the amount of leachate that is created at the landfill and consolidate the leachate that is created to a single location so that it can initially be moved to a treatment facility more easily, he said. Phase two of the project includes a system to treat the leachate on site.
The estimated cost of phase one of the project is $1,485,000, with the entire cost set to be covered by state government, Powell said.
So far, about $191,984 has been invested in the design of the project, he said. The state has contributed $125,000, and the city has contributed about $66,984.
The hope is that ground can be broken on phase one of the project in March, and it will take about six months to complete, Powell said. Completion will be followed by a six-month evaluation period.
Current plans for phase two of the project include using a system called a phytocap to get rid of the leachate, he said.
There have been delays in starting work on the leachate control project because both the exposed geomembrane synthetic cap and the phytocap are methods of leachate control that are new to the state, Powell said.
A phytocap uses trees and plants to absorb the leachate. However, the system is not effective in the winter and leachate will have to be stored and hauled away to a treatment facility during those months, he said.