COVINGTON - Monitoring of methane gas contamination in and around the Newton County Landfill on Lower River Road is being stepped up after the discovery that the previous monitoring system was in disrepair.
There is no evidence that contamination has reached any residential properties, according to Robert Krasko, a hydrogeologist with Geological, Environmental and Management Services Inc., a company recently hired by the county to do environmental monitoring at the landfill.
The migration of methane gas from an old unlined landfill cell that is now closed has been a long-standing issue, Krasko said. It's a problem that's typical in unlined landfills where there is nothing to contain the gas that builds up from the decomposition of buried waste.
Over the years, the county has implemented several methods to take corrective action.
"There were several things done. They were just not maintained and operated adequately," Krasko said.
Krasko was hired by the county in January and soon discovered the existing system, which involved extracting the gas through wells, was not functioning properly.
A solar flare that has panels used to ignite and burn the gas was not working and some vents were damaged, clogged or turned toward the ground preventing venting, he said.
The problems have been corrected, Krasko said, and the county is now working on a long-term solution that involves excavating waste from the unlined cells and moving it to a lined cell.
"There's been no danger to human health out there," he said. "It's always our first concern to make sure everybody is protected."
While gas has been detected at the fence line that borders the landfill property, none has been detected across the street, Krasko said.
"The environmental impacts are located to the south of the Animal Control Shelter owned by the county. There are no residences there," he said.
Gases are broken down by microorganisms in the soil within a few hundred feet of where the are emitted, he added.
As a precautionary measure, however, the six monitoring points required by law will be increased to 36.
The animal shelter and Keep Covington/Newton Beautiful office are being monitored, according to District 4 Commissioner J.C. Henderson, who said he's concerned about the situation.
Henderson said he first heard about the problem when he was elected 12 years ago.
At that time, the county was told that contamination had reached across the street.
"What have we done since then to stop it?" he said. "We're talking about people's lives.
"If we are monitoring the animal control shelter, we should monitor people's homes," he said.
Henderson said he wants to hold a public meeting to inform residents of the situation, an idea Krasko said he supports.
The better informed people are, the less likely they are to panic, he said.
The county is taking action to permanently resolve the issue, applying to redesign the entire landfill and in doing so, tripling its life expectancy, he said.
The landfill currently includes one unlined cell and one lined cell, along with two unlined construction and demolition cells, one of which is not in use.
Currently, the landfill waste comes to within 50 to 100 feet of the property boundary, Krasko said.
The new design will increase that to 200 feet.
Since the gas is migrating between 50 and 100 feet from the waste, the new design should prevent any gas from the existing cell from getting to the property boundary, he said.
Though the landfill capacity will be increased, expansion is a misleading word, he said, because property boundaries will not increase. The expansion will occur internally, not laterally, by filling dead space.
Krasko described the expansion as similar to lining up three isoceles triangles and then filing in dead air space with upside down triangles.
This method, which will extend landfill capacity by 20 years, is a fairly new trend in the industry, and is more cost-effective than building a new landfill, he said.
"It's already there, it's gong to be there for a very long time, so why not utilize the property much more wisely?" he said.
Crystal Tatum can be reached at firstname.lastname@example.org.