Air quality monitors near the underground fire at a landfill in Moody show the hazard is continuing to pollute the air more than 50 days after it began.

The air quality monitor closest to the fire registered unhealthy conditions on Monday, AL.com reported, although the monitor later reported improving air quality. Another air quality monitor in Trussville showed pollution levels that are acceptable, but may present a risk for some people with 24 hours or more of exposure, especially those who are unusually sensitive to air pollution, the Associated Press reported.

In late December, air quality readings over the threshold for hazardous, which is worse than the unhealthy level, were common near the fire.

A class-action lawsuit was filed in December against the owners and operators of the Environmental Landfill, Inc., which owns the site. The lawsuit, filed in St. Clair County, cites inspection reports from the Alabama Department of Environmental Management. They note the presence of unauthorized waste at the landfill and describe the site as a fire hazard.

Representatives of the company have declined to comment to news outlets.

St. Clair County Commission Chairman Stan Batemon said he still gets smoke complaints, but the fire is actually shrinking, according to the AP.

He said ADEM officials told him the smoke hugs the ground in the mornings and evenings, making air quality worse.

St. Clair County has declared an emergency, but is not authorized to spend money on private property, Batemon said. He said the fire could take another month or more to burn out.

Environmental experts have warned against pouring water onto the fire, Batemon said, saying steam could carry more impurities into the air and runoff could pollute the Cahaba River.