Just a few hundred yards from Lake Robinson lies an old waste pond that, until this year, was among the least of Duke Energy’s worries in the Carolinas.
The pond had virtually dried up and, as coal ash basins go, didn’t appear to present the same threat to groundwater, rivers or lakes that other ash basins do, environmentalists say.
But documents that have surfaced recently show the unlined 55-acre basin has leaked arsenic – and it has the unusual legacy of being a dump site for low-level nuclear waste. Both findings are producing new questions about how to cleanse the mess at Duke Energy’s H.B. Robinson power station.
Pollution test results from last year show that the Hartsville plant’s coal waste pond has released higher levels of arsenic into groundwater than state regulators ever had recorded there. In some cases, the arsenic levels rival those at other power plant sites in South Carolina that already are undergoing cleanup.
And in the 1980s, at least 69,000 cubic meters of radiation-tinged sediment wound up in the coal ash pond from the nuclear plant, a rare occurrence because most power plants don’t include both coal-and nuclear-fired units.
State regulators in South Carolina said they knew of no other power plant site where atomic waste wound up in a coal ash pond. A spokesman for the Nuclear Regulatory Commission in Atlanta said the practice is rare.
Records show the Robinson plant’s former owner, Carolina Power & Light, received federal approval to put low-level nuclear waste in the ash pond after arguing it would be expensive to ship the material to a low-level atomic waste dump in Washington state. Some radioactive material in the waste was not suitable for South Carolina’s low-level nuclear waste landfill in Barnwell County, records show.
Duke spokeswoman Erin Culbert said the company, which acquired the site as part of a corporate merger in 2012, is learning more about both issues. It will determine how to best address a cleanup at the eastern S.C. site, she said.
“Those are the exact types of issues we are considering when we recommend the appropriate” cleanup strategies, Culbert said. “All of those things would be weaved into that closure recommendation.”
Duke, under pressure to clean up coal ash ponds across North and South Carolina, has several options for dealing with the material.
It could dig up all the polluted ash and haul it to a landfill. Or it could cap the old waste ash pond to keep water from leaking in, which in theory would stop any further leaks into the groundwater.
One of Duke’s chief critics says the company should dig up the ash and truck it to a lined landfill, as soon as possible. That would limit future leaks to groundwater and threats to nearby Lake Robinson from either arsenic or radioactive material, said Frank Holleman, a Greenville attorney who is with the Southern Environmental Law Center.
“This site needs to be cleaned up, and the ash needs to be removed,” Holleman said. “It will ensure the lake, the aquifer and the surrounding community are protected.”
Potentially complicating such disposal is the low level radioactive waste. In some cases, it is legal to dispose of such waste in municipal garbage landfills. Anti-nuclear activist Tom Clements said he’d like to know more about whether a better disposal site would be an atomic waste landfill. Clements also said that digging up the ash could cause radioactive material to become airborne.
Holleman said leaving the ash in place won’t stop the source of leaking arsenic. He said he was shocked to find that the Robinson plant waste pond, in addition to having coal ash in it, also contained nuclear waste – and that groundwater beneath the pond had high levels of arsenic. Arsenic typically is associated with coal ash disposal.
“I didn’t expect this because there were no previous reports with that high a level of contamination,” Holleman said. “And nowhere have I seen low-level radioactive waste disposed of in an open ash pit.”
The arsenic levels rival those of what were considered some of the most contaminated coal ash sites in South Carolina, said Holleman, who found out about the arsenic pollution and nuclear waste disposal through a state open records request.
Up to 18 feet of coal ash buried at the Robinson site are saturated by groundwater, even though much of the surface water from the pond has evaporated, records show.
The law center has been in the midst of a legal war with Duke Power in North Carolina over ash pond cleanups. Duke Energy has only two sites in South Carolina with coal ash ponds. Until recently, most of the attention in South Carolina was on two Duke ash ponds in Anderson County. Duke has agreed to dig up and remove the ash from the ponds along the Saluda River.
So far, Duke says there is no evidence Lake Robinson is being polluted by cobalt-60, the material CP&L put in the ash pond decades ago. But the long-term impact is unknown.
The 2,250-acre lake, built in 1959 to provide cooling water to the site’s power plants, today is not a drinking water source. But it is popular with recreational boaters, anglers and campers. Many people who live in the area are served by a public water system, although some drink from wells.
Many enjoy lake
A drive along the shores of Lake Robinson reveals a collection of camper trailers, mobile homes, public boat landings and private campgrounds.
The lake is not an upscale reservoir, like Lake Murray near Columbia or Lake Keowee near Clemson. Still, Robinson has a loyal constituency of people who pack the lake on busy summer days, swimming and fishing in its waters.
Among the most popular spots at Lake Robinson is Johnson’s Landing, a campground directly across the water from the nuclear energy plant and the old coal ash pond. It includes a swimming beach, a tire swing, picnic tables and areas to grill hamburgers.
On a cool March afternoon, the campground contained about a half-dozen trailers, but by midsummer, the property will be packed with tents – and visitors, owner Jimmy Johnson said.
“People come in and they’ll put up tents for the weekend,’’he said. “They’ll have boats and jet skis and all this kind of stuff. And (they will be) swimming.’’
The 61-year-old Johnson said he had not heard about the arsenic leaks and nuclear disposal practices until a reporter for The State newspaper showed him documents detailing the problem. While he has never worried about contamination from the plant and he said the power company has been a good neighbor, Johnson would prefer that Duke remove the coal ash from the site.
“I would, now that I know about the arsenic,” said Johnson, who said he was about 5 when the lake was established on land his family used to farm. “What about 10 years from now or 20 years from now, with my grandchildren running around?”
Charles Wilson, 66, said contamination threats to the lake need to be addressed.
He has caught plenty of bass, catfish and crappie on Lake Robinson through the years. One of his favorite places was the “Hot Hole” because it was a hot spot to land fish. It no longer is open to the public, but there are plenty of other places to cast a line, said the Vietnam War veteran who moved home to Darlington County in 2003.
“If that contamination gets out there in the water and stuff, I imagine some of the waste products could get into the fish and could harm you from eating the fish,” said Wilson, as he took a break from fishing with his buddies near a boat landing on the lake’s upper end.
Neil Montgomery, who can see the nuclear plant from the back yard of his lakefront house, said his daughter sometimes worries about his grandchildren swimming in the lake. But he said he’s not particularly worried about the nuclear plant or the coal waste pond.
Nuclear and coal plants are regulated by government agencies, said the 75-year-old Montgomery, who worked in the coal industry in West Virginia before retiring to Lake Robinson 25 years ago.
“I’ve got no problem,’’ he said. “I was concerned about (the nuclear plant) when I first moved here, but I don’t pay any attention to it at all now.’’
Cobalt and arsenic
Duke’s 177-megawatt coal plant, built in 1960, closed in 2012 amid national concerns about how the burning of coal was contributing to climate change. The 724-megawatt nuclear plant, completed for use in 1971, still is operating.
The most unusual environmental issue centers on the disposal of cobalt-60 in the ash pond during the 1980s. The material, like other radioactive contaminants, can cause cancer if ingested through water or food. It can linger in the environment for decades.
Records show that the Nuclear Regulatory Commission allowed the disposal of cobalt-60 in the Robinson ash pond on at least two occasions, in 1983 and 1984 – after then-owner Carolina Power & Light had dumped the material at least once in the pond without federal approval. Records indicate that disposal also occurred in 1998.
In 1983, Robinson plant managers said it would be more expensive to send the radioactive material to a disposal site in Richland, Wash. That would cost more than $13 million, the company said. Dumping it in the Darlington County ash pond would cost only about $100,000, according to a 1983 request to the NRC.
Records show that Progress was denied access to dispose of the material at South Carolina’s low-level nuclear waste dump at Barnwell. A form of radium in the waste was considered “technologically enhanced,” records show. That classification can indicate that relatively benign, naturally occurring radioactive material has become more radioactive because it has been packed together and concentrated.
S.C. Department of Health and Environmental Control spokeswoman Cassandra Harris said the cobalt-60 has not been found in any detectable concentrations in groundwater at the Robinson plant. But nuclear waste disposal is rare in a coal ash pond, and she said it “will be part of the evaluation” on how to close the pond.
Meanwhile, arsenic – historically used as a poison – is a more immediate question. Arsenic, often associated with coal waste, has been linked to cancer of the bladder, lungs, skin, kidneys and nasal passages, according to the U.S. Environmental Protection Agency.
Test results in a December 2014 consulting report showed levels of arsenic in one shallow well below the pond that are more than a hundred times higher than the level considered safe for drinking. Records show the well at the ash pond site contained arsenic levels in excess of 1,000 parts per billion, according to the report for Duke. The safe drinking water standard is 10. The December report also noted elevated levels of nine pollutants in the ash, including mercury, lead and selenium.
The December report outlined the high levels of arsenic in groundwater after DHEC hit Duke with a notice of violation last fall for exceeding safe drinking water standards. But at the time, DHEC only had discovered arsenic levels of 115 parts per billion, or just over 10 times the drinking water standard.
A follow-up report for Duke, completed last month, said two other wells at the pond had arsenic levels that exceeded the standard of 10. Both readings were higher than previously found at the site before 2014. DHEC’s Harris said the highest arsenic level previously found in groundwater at the site was 23 parts per billion in 2011.