FARGO — Unsafe contamination from coal ash disposal sites at half a dozen power plants in western North Dakota has seeped into groundwater sources, according to a report from an environmental group.
The Environmental Integrity Project collected industry monitoring data for its nationwide report, which found that six of seven coal-fired power plants in North Dakota leaked contamination into groundwater sources at levels exceeding those deemed safe — in one case, by a factor of 100.
But state health officials and representatives of the utilities that run the coal-fired power plants say none of North Dakota’s ash disposal sites fail to comply with standards set by the Environmental Protection Agency.
The report appears not to have used the requirement of logging “statistically significant increases” that the EPA uses to determine whether higher monitoring readings reflect pollution or high background levels that occur naturally, said Chuck Hyatt, director of the waste management division of the North Dakota Department of Health.
“Their methodology is significantly different than the methodology that the EPA recommends in its CCR rule,” which governs disposal of coal combustion residuals, including ash, he said.
The authors of the report, released this month, said 91 percent of the nation's coal plants have unsafe levels of one or more coal ash constituents in groundwater, "even after we set aside contamination that may be naturally occurring or coming from other sources."
Although the report said unsafe levels from coal ash disposal sites were detected in groundwater near those sites, the report did not find that drinking water supplies were affected by the contamination in North Dakota.
Among the report’s findings for coal ash disposal sites in North Dakota — all of which the sites’ operators deny actually exceeded allowable levels or caused groundwater contamination:
Antelope Valley Station near Beulah in Mercer County had levels of cadmium 100 times greater than levels considered safe, a level the power plant’s owner calls incorrect.
Coal Creek Station near Underwood in McLean County had levels of arsenic that were twice the level deemed safe; nine times for boron, six times for cobalt, twice for lead, 15 times for lithium and 10 times for sulfate.
Coyote Station near Beulah had cobalt concentrations five times the level considered safe, selenium twice the safe level, and sulfate 10 times greater.
R.M. Heskett Station near Mandan in Morton County, which is slated to close in 2021, had levels of lithium 54 times greater than levels considered safe and sulfate 21 times greater than safe levels.
Stanton Station, which was near Stanton in Mercer County before it was demolished last fall, had levels of arsenic 18 times greater than considered safe, molybdenum at twice safe levels.
Leland Olds Station near Stanton had unspecified "unsafe" groundwater readings.
“This is a wake-up call for the nation,” said Lisa Evans, senior counsel with Earthjustice, which helped the Environmental Integrity Group on the report. “Using industry’s own data, our report proves that coal plants are poisoning groundwater nearly everywhere they operate.”
No regulatory violations
The information cited in the report, compiled from 4,600 groundwater monitoring wells surrounding the ash disposal sites of 265 coal-fired plants around the country, was recently made public for the first time under federal coal ash requirements issued in 2015.
Nationally, groundwater near 242 of the 265 power plants with monitoring data contained unsafe levels of one or more pollutants, according to the report. Even if drinking water supplies are not immediately threatened, more stringent regulation would help before contamination gets worse and travels farther in the environment, the report said.
“None of the solid waste facilities associated with the power plants in North Dakota have compliance issues and have not had any notices of violations,” said Diana Trussell, the state’s solid waste program manager.
How to explain, then, the “unsafe” levels in the Environmental Integrity Project’s report? It’s hard to say, Hyatt said, especially since the report lists contamination levels as multiples of safe levels, rather than listing actual values.
Hyatt rejects the possibility that groundwater contamination could have resulted before the state adopted its more stringent regulations in the early 1980s.
“Indiscriminate disposal of coal waste into surface mines has not occurred for twenty years,” according to a 2002 North Dakota Department of Health report that outlined the history of coal waste disposal in the state.
“There will be variability in any dataset — the statistical method allows us to determine with some confidence if the variability is the result of actual changes in concentration, or random error,” Hyatt said. “Selecting an individual datapoint or simple average, as it appears EIP did for their report, does not provide these assurances.”
Also, because the report does not give the sampling date and specific location, such as the monitoring well designation, he said, “This makes it extremely difficult to quickly go back to the original date and find the numbers that they used.”
In 2014, in a decision that was controversial at the time, the EPA labeled coal ash as a non-hazardous waste. A hazardous waste designation would have cost each of North Dakota’s coal-fired power plants millions of dollars in operational changes, industry representatives said at the time.
The Trump administration is trying to roll back federal regulations on coal ash, a move criticized by environmentalists.
Power companies respond
Since March 2018, most coal plant owners, including those for all plants in North Dakota, have posted the results of their initial groundwater monitoring online, as required.
Utilities that own the coal-fired power plants in North Dakota echoed state health officials in saying their ash disposal sites are in compliance with regulations.
If monitoring identifies concerns, the rules require the utilities to take corrective action. The rules also require notification of property owners if their wells have been impaired by contamination.
“No exceedances have been observed at any of our facilities that would be indicative of groundwater contamination from our CCR units,” or coal combustion residual waste, including ash, said Stephanie Hoff, a spokeswoman for Otter Tail Power Co., which owns the Coyote Station near Beulah.
“No groundwater impacts have been identified at OTP’s facilities,” Hoff said. Later this year, she added, Otter Tail Power plans to close and remove coal ash from impoundments at Coyote Station. Last year, it closed its coal ash impoundments for its power plant near Big Stone, S.D.
Joan Dietz, a spokeswoman for Basin Electric Power Cooperative, which owns Antelope Valley Station near Beulah, said the report’s reference to cadmium levels 100 times the safe level is incorrect.
“The analytical results show all but one sample taken at Antelope Valley indicated undetectable amounts of cadmium, with one sample detecting less than one-tenth the limit, which is five micrograms per liter,” Dietz said. “We are in compliance, with absolutely no evidence of any contamination.”
The same is true for Montana-Dakota Utilities’ R.M. Heskett Station near Mandan, said spokesman Mark Hanson.
“No groundwater impacts from R.M. Heskett Station’s coal ash landfill have been observed at this time,” he said, adding the site is in compliance. “We continue to monitor groundwater as the rule requires and address corrective action if that would change.”
Hanson added: “It is important to note that even if groundwater impacts are identified at a facility, that does not necessarily mean drinking water is affected downstream of the facility.”
Minnkota Power Cooperative’s Milton R. Young Station near Center had levels of lithium about equal to the EPA groundwater protection standard, according to the Environmental Integrity Project’s report.
“We are confident that this measurement is not attributable to our coal-ash disposal facility, but at levels typical of groundwater quality around our facility,” Minnkota spokesman Ben Fladhammer said.
A spokesman for Great River Energy’s Coal Creek Station near Underwood said the power plant’s ash disposal site is in “full compliance” with all regulations.
“To date, there have been no indications that our existing CCR units” — coal combustion residuals, or ash — "are contributing to groundwater contamination,” said Great River spokesman Lyndon Anderson.
ND plants produce millions of tons of coal ash waste
North Dakota mines roughly 30 million tons of lignite coal each year. Most of it is burned to generate electricity at power plants dotting the prairie in west-central North Dakota in the Missouri River Valley.
All of that coal produces millions of tons of coal ash waste — 2.7 million tons in 2017, according to the most recent state figures available.
Of that total, 640,147 tons were used in some manner, including soil stabilization, as an ingredient to make concrete, and to solidify drill cuttings from bore holes, including oil and gas wells.
For example, Great River Energy’s Coal Creek Station is a 1,200-megawatt power plant near Underwood. It produces about 500,000 tons of ash each year, and sells or donates about 400,000 tons.
Coal ash can be used to make concrete stronger and reduce costs. Great River has sold coal ash to ready-mix companies for more than two decades, and the company says the ash is found in nearly all concrete poured in North Dakota.
State health regulations require coal ash disposal sites to have a liner comprised of two feet or more of clay soil and a thick, impermeable plastic layer. Once retired, they must be covered with a vegetation cover and monitored for at least 30 years.