Imagine a temporary dam reaching deep into the Congaree River in the Vista, with walls that protrude some 14 feet above the water, as part of a three-year environmental cleanup that also is likely to uncover Civil War munitions.
SCANA Corp.’s $18.5 million project to remove about 40,000 tons of black tar discharges from a power plant that closed six decades ago should look something close to that.
Tar was discovered in the water near the Gervais Street bridge several years ago. SCANA in 2010 told the public it would have to come out. But only now is anyone beyond a select few finding out the scope of the project and the fact that studies have shown that buried beneath the tar are objects that are likely captured Confederate ordnance dumped by Union troops 150 years ago.
The stone cofferdam under consideration by state and federal environmental regulators calls for it be 171/2-feet tall, to have a 60-foot base and to snake as much as 3,990 feet around the edges of the dam, between the Gervais and Blossom street bridges. Behind the dam, about 15 acres of river bottom will be exposed in stages and scraped clean to the bedrock.
Never miss a local story.
The project will be surrounded by 2,100 feet of fencing, 210 warning signs, security guards and include construction of a debris-processing shed, a paved truck-hauling road and a prefabricated bridge to protect a city sewer line.
From May to December each year, river water would be diverted to the West Columbia side while workers remove tar described as being solid to taffy-like and averaging 2-feet thick.
The cap over natural sediment is up to 150 feet wide and 1,800 feet in length. The target area extends plume-like from the Columbia side of the riverbank to nearly 200 feet into the scenic river that measures about 800 feet wide at that point. The tar emits a distinctive oil-like odor and health officials say it poses a risk to humans only by direct contact.
Those descriptions are taken from the utility company’s formal proposal to regulators who have yet to approve required permits because they have many questions about the project, first proposed in 2002.
SCANA’s director of environmental services, Tom Effinger, would not discuss details of the project, citing the ongoing permitting process. Neither he nor a SCANA spokeswoman would acknowledge the likelihood of military ordnance under the tar cap.
“We don’t have any direct knowledge of ordnance,” Effinger said. “We don’t know if it’s hubcaps or what is there.”
Yet Effinger did not dispute data from a survey it commissioned from a Columbia research company. A September 2014 draft report by Tidewater Atlantic Research obtained by The State newspaper, states that a list of “potential unexploded ordnance” locations were found. More than 400 samples were found as “potentially being ordnance.” That includes 67 that demonstrate “signature characteristics” of what could be ordnance.
Congaree Riverkeeper Bill Stangler said he’s been working with the utility on the project for about 21/2 years as an advocate for the river. “I don’t know how much we’re supposed to say about that,” Stangler said.
Effinger said SCANA’s message is one of reassurance.
“Whatever we do in the river, we’re going to do it right and we’re going to do it safe,” the utility executive said. “We’re going to make sure we do this thing the best way possible.”
Project being changed, shrunken
SCANA, its subsidiary, South Carolina Electric & Gas Co., and the regulators decided Wednesday that the utility will submit a revised proposal that would scale back the size of the coffer dam and possibly to use material other than stone, Jim Beasley, a spokesman for the state’s environmental regulatory agency, said last week.
The size could be reduced “perhaps greatly,” the Department of Health and Environmental Control spokesman said.
Beasley would not specify the proposed changes, other than to say, “The design is going through substantial revision. The overall effect of the revised design will be to reduce in scale the size of the coffer dam, and, possibly, to use different materials.”
DHEC and the U.S. Army Corps. of Engineers, the lead federal agency on the project, have raised a number of questions about it.
Brice McKoy, supervisor of the Corps’ Columbia office, said its list of concerns range from water topping the temporary dam when the river is flush to backwater effects and clean up procedures.
He declined to itemize the issues his agency has but said they amount to about 21/2 pages. That’s not an unusually large number of concerns for a cleanup of this magnitude, McKoy said.
“This is a very complex project,” he said. “Imagine damming up half the Congaree River. We want to make sure that this thing is done absolutely correctly. We’re talking public safety, so we don’t want to rush (SCANA).
“The corps does have concerns about the project and those concerns are currently being addressed by the applicant,” McKoy said.
SCANA officials would not discuss the talks, which have gone on throughout the permitting process. Public discussions will occur once permits are finalized, they said.
Effinger declined to detail the issues raised by regulators. But he said the dam’s height is one of the key matters in question.
None of the parties to the dredging project would say when permits might be approved.
The budget of $18.5 million – all paid by the utility – will not result in rate increases for SCE&G customers, Effinger said. SCANA has a fund set aside for environmental cleanups, among them the Congaree River project, which is one of the largest, he said.
Some 22,000 truckloads of debris will have to be removed from the site, according to a source long familiar with the project.
The truck access route to the project is to be moved from SCANA’s first proposal in the Vista southward, near the University of South Carolina baseball stadium, said Dixon Lee, an attorney who lives in City Club on Gervais Street, the closest residential site to the dig. Owners in the high-end complex of 38 condos overlooking the river opposed the original route, which would have taken trucks along Gervais, Huger, I-126 and I-20 to a Richland County landfill.
Lee said he and other City Club owners have held numerous meetings with SCANA officials for 18 months.
“Our chief concern was that it would create a traffic nightmare,” Lee said. “You can imagine six months for three years of huge trucks going in and out. We got a huge accommodation when they agreed to go the other way.”
Effinger would not talk about the new route. He said the state Department of Transportation and the city of Columbia must first finalize it.
On Feb. 17, 1865, Gen. William T. Sherman’s Union army stormed and burned Columbia after shelling it from afar as they headed north after taking Savannah.
An inventory of the rebel ordnance and ordnance stores captured that day lists:
• 1.2 million ball cartridges
• 100,000 percussion caps
• 6,000 unfinished arms
• 4,000 bayonet scabbards
• 3,100 sabers
Some of those weapons have long been believed to be at the bottom of the river. Through the years, fishermen and swimmers have found some munitions. And in the 1930s, a large cache was salvaged from the sandy bottom.
But how much history is buried under the tar and its condition remain mysteries.
James Spirek, the state’s underwater archeologist, said he’s not persuaded that lots of Civil War armaments will be found. “I’m sure there will be some interesting items. I don’t anticipate huge volumes.”
But historians and Civil War enthusiasts are excited about what treasures the dredging will unearth.
Instructor Bill Thomas discovered the tar during a lesson in May 2010 while teaching inexperienced kayakers how to do “Eskimo rolls” so they could right themselves after tipping over.
“I waded into the water,” Thomas said. “First I noticed the smell. When I got out of the water there was a gooey, black gunk ... all over my feet. It smelled strongly of petroleum.”
He reported what he saw to DHEC, which began looking into the complaint.
Downstream water quality effects from the tar are negligible, according to documents reviewed by the newspaper in regulatory files. The Congaree is one of the city’s sources of drinking water as well as being popular for fishing, walking and recreation.
The coal tar came from a gas-making plant once located on Huger Street between Hampton and Williams streets. It was completed in 1906 and closed in 1954 before there were national pollution standards.
The plant produced flammable “town gas,” which was used for heating, cooking and lighting before the city had natural gas pipelines. A series of purchases of the company that owned the plant ended when SCE&G was listed as its owner by 1950, according to documents filed as part of the environmental permitting process.
Records SCANA has sent to regulators show more than a dozen different chemicals were found in river sediments at levels of concern.
Those include benzene, which can cause cancer, and related compounds. In some cases, the levels were higher than levels typically considered safe in soil.
Benzene was discovered in an alluvial fan and sand bar of the Congaree, as well as some other areas. They are at concentrations that exceed residential screening values, according to the Interstate Technology Regulatory Council.
Concentrations of pollutants above screening values often require further investigation. But there are no national criteria or standards for chemical concentrations in sediment – only guidelines, SCANA’s project manager of the cleanup, Bob Apple, wrote in a Jan. 15, 2013, report to DHEC.
A risk assessment of the project site found “the cumulative ... cancer risk was exceeded for the recreational user. Therefore, it may be concluded that the cumulative ... cancer risk would be exceeded for the Congaree River sediment containing (the tar),” Apple’s report to DHEC states.
Apple’s report also noted the project area contains a diverse ecology, including flora.
The short-nosed sturgeon is on the federal and state endangered species list while the Rafinesque big-eared bat is listed as endangered only by federal officials. The Gervais Street bridge is a roosting area for the bats. Several species of mussels and the Rocky Shoals spider lily also inhabit the area. That lily is a “species of concern” under federal standards.
Apple cited a 2007 short-nose sturgeon study done as part of relicensing a hydroelectric plant found no captures of the fish or its eggs.
Attorney and City Club resident Lee said he did Internet searches that showed that a short-nosed sturgeon has not been sighted in rivers immediately around Columbia since the 1920s.
Lee has dubbed the fish “the hypothetical short-nosed sturgeon.”
Yet the prospect of the fish being in area rivers has forced SCANA to drop plans to do year-round work on the project, Lee said, citing that he and his neighbors received their most recent update from Apple in December.
And the utility company has offered to shorten work on the project by a year, the attorney said. SCANA is proposing two stages of dredging instead of three to ease any impact on the sturgeon, Lee said.
Effinger would not discuss proposals that have not been formalized in a permit.
Apple told Stangler, the riverkeeper, in a July 31, 2014, letter that the shore, including the site of a processing facility for the debris before it is trucked away, will be disturbed minimally and will be repaired after the project ends.
City Club homeowner’s association president, Rebecca McMillan, said she supports the cleanup despite the inconveniences.
“Our (City Club) community – which this is not something that we coveted – feels we’ll be much better off for not having that tar in the river.”
Fellow resident Mary Langston sees a broader advantage. “In the long run, it’s going to be a benefit for all of Columbia.”