State, power company abandon plan to dig up polluted coal tar from Congaree River
At the request of state regulators, SCE&G has abandoned plans to excavate and remove polluted coal tar from the Congaree River in a decision that could save the power company $11 million, records show.
The utility, which is responsible for addressing the contamination, would leave tons of coal tar on the bottom of the Congaree and cover some of the river bed with fabric and stones, according to federal and state correspondence reviewed by The State newspaper.
That’s a significant departure from SCE&G’s plan two years ago to deal with tar that drained from a company-owned site. At the time, SCE&G had developed a plan to temporarily dam part of the river so it could excavate the gooey material and haul it away. The project was expected to cost $18.5 million.
But in correspondence with the utility, the S.C. Department of Health and Environmental Control said diverting the river with a dam or sandbags isn’t practical, so the excavation can’t be done.
A temporary dam could cause erosion on the river’s shoreline and flooding in some areas, while sandbags simply would not work, agency officials said. The project’s potential for success was further compromised by a 2015 flood that deposited up to 5 feet of new sediment atop the tar, DHEC spokeswoman Jennifer Read said in an email Tuesday.
The agency told SCE&G in August to leave the material in the river bed and cover it with a cap, most likely composed of stones, records show. The area is near the Gervais Street bridge and covers less than 3 acres of river bottom.
“Based on the construction and permitting limitations, it is not feasible to conduct a removal of the (tar) impacted sediment in the Congaree River,’’ according to an Aug. 16 letter from DHEC to SCE&G, which was obtained recently by the Congaree Riverkeeper. The letter said “SCE&G should begin the design and permit process for the capping alternative, as soon as possible.”
Leaving the material in the riverbed and putting a fabric-and-stone cap over it would cost the company about $7.7 million, about $11 million less than originally proposed, a spreadsheet on DHEC’s website shows.
The change in plans, which is not final, sparked criticism Tuesday from the Congaree Riverkeeper organization. Riverkeeper Bill Stangler said the new plan was hatched without a chance for the public to comment. Stangler said SCE&G and government agencies, including DHEC, have known about the shift in plans for months, but only confirmed the change when he asked them about it recently. He said reasons for the change are unconvincing.
“You can’t just say this project got harder, so we’re not going to do it,’’ Stangler said. “We are very concerned about the direction this has taken. SCE&G was very public about their commitment to cleaning it up several years ago. When the plan shifted, they did it very quietly. That concerns me for the future and health of the river.’’
The S.C. Department of Natural Resources also has expressed reservations, including whether placing a stone cap in the riverbed could be hazardous to swimmers, fishermen and others who walk in the Congaree. The agency urged the U.S. Army Corps of Engineers, which like DHEC must authorize the project, not to approve it, as proposed, unless regulators can satisfy environmental concerns.
The coal waste, which DHEC calls “tar-like material,’’ contains an array of chemicals, including carcinogens such as benzene and a class of chemicals known as polynuclear aromatic hydrocarbons. Many sediment and soil samples collected from the tar-coated river bed have shown “high levels of contamination’’ above recommended federal levels, according to DHEC’s website.
Agency officials say, however, that the material is only a risk to people who come in skin contact with it. They say the water of the Congaree is not contaminated with “tar-related chemicals of concern.’’
SCE&G spokeswoman Ginny Jones said DHEC has told her company that the plan to put a cap over the coal tar and leave it in the river is enough to restore the area for recreational use. Work should begin this year on the capping project, Jones said.
“The cap, when in place, will create a permanent barrier between the affected sediment and recreational river users,’’ she said in an email. “Over time, the cap will be covered by silt that will naturally deposit over the capped area.’’
DHEC’s Read said “the original cleanup option is no longer feasible or safe.’’ But Read said the public would get a chance to comment at a future meeting.
The health of the Congaree River is significant because the waterway is a recreational attraction for Columbia. Formed by the Saluda and Broad rivers, the Congaree runs through the center of town and separates the capital city from West Columbia and Cayce.
Kayakers, canoeists, fishermen and tubers regularly use the rocky river, which flows past Congaree National Park to the Lake Marion area 50 miles downstream. The area where the coal tar was found is near a public boat landing next to the Gervais Street bridge. A kayaker reported the coal tar to state regulators in 2010 after stepping in the black muck near the public landing.
The department then launched an investigation that indicated the tar had come from an early 20th century manufactured gas plant uphill from the river near Huger Street. The tar had apparently been on the river bottom for more than 50 years.
Leaving polluted soil in place and stabilizing contamination is sometimes used on industrial cleanup projects. Rather than cleanse industrial sites to pristine standards, regulators sometimes allow for more limited cleanups so the site can be used again by businesses.
Capping projects can rely on rock, synthetic sheeting or other material in an effort to seal an area and prevent polluted sediment from being dispersed. A site SCE&G developed in the Charleston area relied on a cap that covered coal tar, according to the Corps of Engineers.
Stangler, the Congaree Riverkeeper, said coal tar pollution is nothing to dismiss — and leaving it in the river is risking future environmental problems.
Coal tar “is highly toxic, and the proposed capping operation is not necessarily a permanent solution or the most environmentally beneficial option,’’ he said in a Dec. 20 letter to the U.S. Army Corps of Engineers. “In fact, these sorts of liners are known to fail and to continue to result in the release of toxic materials into nearby waters.’’
In the Dec. 20 letter to the Corps, Stangler said the project design was revised “with no notice to interested parties like Congaree Riverkeeper.’’
Stangler said he understands the cap would consist of blocks of stone, akin to pavers used in people’s back yards, that would be dropped into the river. Underlying the stone would be a geotextile material that is supposed to seal the tar and keep pollutants in the tar from escaping. The work could be done without diverting the river.
Sen. John Courson, R-Richland, and Rep. James Smith, D-Richland, said they were concerned about abandoning the excavation project and want to know more. Courson said he learned about the proposal to leave the coal tar in the river only last week.
This story was originally published January 3, 2017 at 8:49 PM with the headline "State, power company abandon plan to dig up polluted coal tar from Congaree River."