Champ Landfill in Maryland Heights will pay $1.6 million in air quality improvements, under the terms of a settlement it reached with the Environmental Protection Agency Thursday.
Agency officials inspected the landfill in May and detected methane emissions from the surface that exceed the federal limit. Methane makes up 50 percent of landfill gas.
"Those values were exceeded approximately 16 times during our inspection," said Mark Smith, chief of the air permitting and compliance branch for EPA region 7. "We suspect they are not conducting the monitoring properly."
EPA regulation states that surface methane emissions should not exceed 500 parts per million. Officials found levels as high as 10,000 parts per million at Champ Landfill.
At high concentrations, methane can displace oxygen in the air and can cause difficulty breathing, headaches, nausea and other health effects.
Federal officials don't know the cause of such excessive amounts of methane. The agreement requires Champ Landfill to pay for a third party to investigate its gas collection system and install 21 landfill gas extraction wells. The landfill has 60 days to complete the audit and another 180 days to execute a compliance plan.
Ed Smith, policy director at the Missouri Coalition for the Environment, said he feels confused about the settlement.
"It really leaves me more questions than answers about what's going on at Champ Landfill," he said. "The fact that they're installing more gas extraction wells means that they're collecting more gas and does that mean there are more flares at the landfill? And if there are more flares, what impact is that having on air quality?"
Champ Landfill sits about two miles from the West Lake Landfill in Bridgeton, close to where many residents have complained of foul odors.