The Environmental Protection Agency and other environmental investigators are looking into a strong odor that's been reported along the North Carolina-South Carolina border near Charlotte.
The smell has been most prevalent in South Carolina's Lancaster and York counties but has been reported in many surrounding areas as well.
Residents describe it as an intense, rotting stench that can wake people up at night or cause people to develop nosebleeds and intense nausea.
Thousands of complaints have been filed with South Carolina's Department of Environmental Quality since January, which prompted the state to investigate the odor's origins. A preliminary state investigation took many of the complaints and matched them with wind speed and direction data to figure out where the air may have traveled from.
The results found much of the offending air had passed over or near the New Indy Containerboard paper mill in Catawba, South Carolina.
The investigation also determined the smell was likely due to hydrogen sulfide, which is prevalent around decaying organic matter, such as at a wastewater treatment plant or a pulp or paper mill.
Additionally, investigators say they examined nearby wastewater plants and landfills but found no evidence that they were responsible for the odor.
The paper company has denied that the mill is responsible for the stench. In a response to the state, the company said it hired a team of investigators with the Atlanta-based consulting firm Weston Solutions, who did not find any evidence of strong odors near the facility.
The EPA has since deployed a mobile air monitoring vehicle to Catawba, South Carolina, to conduct follow-up testing.
The paper mill changed from making bleached paper to brown paper in February, and the state says an inspection of the facility found the plant had made several unapproved changes or modifications to its treatment process, and there appeared to be operational issues with the plant's wastewater treatment.
Separately, New Indy had filed a request with South Carolina to increase its emissions by 48% in early April.
State Sen. Michael Johnson of Tega Cay has vocally opposed the request and filed a budget proviso that would prevent South Carolina from approving any emissions increase for any paper companies in York County from July 1, 2021, through June 30, 2022.
"People can't live like they're living right now," Johnson said. "Citizens can't get up with nosebleeds, and people who have asthma can't have asthma attacks every day because of a smell."
The budget proviso passed the state Senate unanimously and is now under consideration by the House.
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