An environmental cleanup company has confirmed that a mistake led to the release of a foul-smelling substance that created a stench in Charlotte on Thursday.
Legacy Environmental Services, LLC released mercaptan during a metal tank recycling process at its North Graham Street location, the company said in a statement to the Charlotte Observer on Friday.
Mercaptan is added to colorless, odorless natural gas, giving it “a characteristic rotten egg odor,” Piedmont Natural Gas said.
According to Legacy, four small tanks were said to have been empty when they were picked up for removal and disposal.
“Dismantling the tanks for cleaning released the mercaptan vapors into the surrounding atmosphere,” the company said.
Around 8:45 a.m. Thursday, reports of the smell of natural gas flooded the 911 system, the Charlotte Fire Department said.
The smell reached many parts of Charlotte due to a temperature inversion. This happens when air temperatures rise at higher altitudes, trapping colder air and odors closer to the surface, according to the National Weather Service.
Several buildings were evacuated as the smell seeped inside, including the Mecklenburg County Courthouse. Firefighters then gave the go-ahead, but the district court closed early as a precaution.
The stench had largely dissipated by mid-afternoon.
The tanks have been resealed and will be prepared for disposal at another location, Legacy said. Authorities have been notified at the time of publication, the company said.
Legacy’s statement did not include an apology.
What is Legacy Environmental?
Indiana-based Legacy Environmental Services was founded in 2003 by Lorrie and Carl Lisek to “fill a void in the environmental industry,” according to the company’s website.
Legacy is an environmental consulting firm that helps the public, private, and nonprofit sectors with policies and practices for “sustainable, more profitable operations,” according to its website.
The company claims to have worked with nearly 500 clients in 17 US states and Canada. Its clientele represents more than 40 local, county and regional government agencies, 15 school corporations and universities, several state and federal agencies, including the US Department of Energy.
Legacy was not hired by Piedmont Natural Gas, and Thursday’s incident did not involve any Piedmont assets or resources, a utility spokesperson told the Observer.
The Environmental Protection Agency has been notified of the leak, according to Charlotte Fire.
Mecklenburg County Air Quality is working with local, state and federal partners to conduct a follow-up investigation into the odorous gas release, said Megan Green, county air quality program manager. It will likely take several weeks to complete a “full and thorough investigation”, she said.
Exposure to mercaptan in NC
Since 2004, eight similar cases of mercaptan exposure have been reported in the state, according to the North Carolina Division of Air Quality’s complaints database.
The most recent complaint, in January 2020, involved a woman from the town of Plymouth, in northeastern North Carolina, who reported that the smell all day was affecting her breathing and sinuses.
According to the database, four complaints involved sawed off, released or tampered with propane tanks.
New Indy Stationery Case
U.S. Representative Ralph Norman, a Republican from South Carolina whose 5th District includes York County, wrote a letter in May urging the EPA to carry out enforcement action against the New Indy paper mill. This would solve the odor issues that many people — including many in south Charlotte — have complained about, according to Norman’s letter.
In December 2021, the EPA proposed a $1.1 million fine against the Catawba paper mill if it failed to address the smell, the Columbia State Journal previously reported. Colorless hydrogen sulfide gas is the biggest source of the odor, but mercaptan is also another contributor to air pollution and the region’s horrible smell.
In May, New Indy said it had made “substantial progress” in reducing hydrogen sulfide pollution and had been in contact with Norman’s office.
This story was originally published July 15, 2022 2:52 p.m.