Toxic gunk cleansed from South Carolina's Congaree River 13 years after first reported. What's next?

Thirteen years after a kayaker reported stepping into a stinging patch of muck in the Congaree River, contractors have cleaned up the toxic mess that covered a stretch of the river bottom below the Gervais Street bridge in Columbia, South Carolina.

Work crews excavated and removed some 38,500 tons of coal tar from two sections of river bed between the Gervais and Blossom street bridges in what has been one of the largest environmental cleanup projects in Columbia's recent history.

The $20 million Congaree cleanup effort was pronounced officially complete during a public event along the river Monday that featured Gov. Henry McMaster, Columbia Mayor Daniel Rickenmann and Keller Kissam, Dominion Energy's South Carolina president.

Officials said the cleanup work, underway for more than a year, finished about a year ahead of schedule.

"There were many who doubted that it could be done, but I'm here today to say proudly that not only did our exceptionally talented and dedicated team do it, they did it in a manner that sets an example for others to follow," Kissam said in a prepared statement.

McMaster, who took a personal interest in the cleanup effort, told the crowd gathered at the river that having to clean up the Congaree shows why it is important to protect the environment. The coal tar is believed to have drained into the river from an old manufactured gas plant, which operated on Huger Street from around the turn of the 20th century to the 1950s.

"There's a lesson in here: That it's easy to mess things up, but it's hard to clean up," McMaster said. "Here we are cleaning up something that was done probably inadvertently without thinking. Everything went into the river back way back then."

"We have to be sure now that what we are doing is not messing something up so somebody has to clean it up later."

With the work completed, Rickenmann said plans to develop parts of the river can move more smoothly. Columbia leaders have long envisioned having a riverfront park near where the cleanup occurred.

The city also wants to expand the system of trails along the area's rivers and plans are on the table to open Williams Street, which runs parallel to the Congaree between Gervais and Blossom streets.

"Opening up the river and the connectivity is something we have talked about for so long," Rickenmann said. "This riverfront is really ..... the catalyst for Columbia."

Perhaps more importantly, the cleanup makes it safer for swimmers and kayakers below the Gervais Street bridge. The area near the end of Senate Street has historically been a popular spot to launch watercraft.

Dominion contractors dug up the material and hauled it away after building two temporary dams to hold back water in parts of the river. The dams, highly visible in Columbia during the cleanup, have now been removed and the state Department of Health and Environmental Control says the project was a success.

Work done in the river occurred on about three acres that contained the vast majority of the coal tar, which was located in two spots where the public might most be likely to have come in contact with it. A small amount of coal tar was left in other, less accessible parts of the river, according to Dominion. Overall, the coal tar was scattered over an 11 to 14 acre area.

Dominion's Tom Effinger said the muck dug from the river bottom was hauled to a landfill on Screaming Eagle Road in Richland County for disposal.

During the cleanup, more than coal tar was removed. Work crews pulled out 2.5 tons of trash and debris, such as tires, Kissam said.

Contractors also found more than 100 Civil War era relics, including a wagon wheel, a Confederate saber, cannon balls and an anchor. Some of the Civil War era relics were believed to have wound up in the river during the time of Union General William Sherman's assault on Columbia in 1865.

Hundreds of other artifacts were recovered from other eras, including from when Native Americans lived in the area.

Work crews found at least one unexploded bomb that was from an era after the Civil War. A special military bomb crew hauled it off. To protect workers, armor-plated heavy equipment was used to dig through the mud, Kissam said.

The cleanup work started in May 2022 after years of disagreements on whether to remove the tar or cover it up with rocks and leave the material in place.

SCE&G, later acquired by Dominion, had initially considered cleaning up the tar in the face of pressure from DHEC. But the company then changed its mind after saying cleaning up the tar would be a difficult, expensive process.

Leaving the tar in place and covering it up with stones and fabric would have saved the company $11 million at the time. SCE&G said it was having trouble getting environmental permits for the work, which is why it opted for leaving the material.

Critics said, however, that it was the company's responsibility to get the tar out of the river since the pollution had drained from the manufactured gas plant site on Huger Street.

Then, after the Congaree River keeper organization threatened a pair of lawsuits, Dominion restarted efforts to cleanse the river bottom of coal tar. The power company restarted the project and got the permits it needed.

Once the cleanup work finally began in May 2022, it went smoothly, officials said.

Coal tar is a goopy black substance generated from the 1800s to the 1950s at manufactured gas plants that produced energy. It is filled with toxins, including cancer causing benzene and substances that can cause tumors on fish.

Nationally, an estimated 5,000 coal tar sites exist across the country, including spots in other parts of South Carolina, besides the Congaree River.

In 2010, a kayaker notified DHEC that he had stepped in the substance, prompting the agency to post public warning signs along parts of the river. Other people, including riverkeeper Bill Stangler, also came in contact with the burning muck.

Stangler, the riverkeeper for the Congaree, Broad and lower Saluda rivers, said the coal tar cleanup took a lot of effort on the part of his organization, state regulators and local politicians. Had people not pushed the power company to restart the cleanup, it may never have been done, said Stangler, who said he was not invited to Monday's public event along the river.

"We've been advocating on this for more than a decade, ever since a local river user stepped in that tar," Stangler said. "It took a lot of work to get there. It was contentious at times, but we are happy to see this project get done."

"It sends a signal to our community and communities across the country that if you stand up and speak and fight for your rivers, great things can happen."

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