A new analysis of data collected from coal-fired power plants shows that groundwater contamination from coal ash dumps is nearly universal.

The Guardian writes that of the 265 coal power plants in the U.S. that monitor groundwater, 242 of them report unsafe levels of at least one pollutant. Contaminants include arsenic, a known carcinogen, as well as cobalt, cadmium, and lithium.

The study, led by Environmental Integrity Project (EIP) attorney Abel Russ, is based on data that became available to the public for the first time in 2018, three years after new federal coal ash regulations were issued. EIP and Earthjustice, which also took part in the study, said stronger regulations are needed to protect drinking water from contaminants.

Data was collected from more than 4,600 monitoring wells around ash dumps at the 265 coal-fired plants, about three-quarters of the total number of coal-fired plants operating in the U.S. The remainder of the plants were not required to meet the federal monitoring rules because they had closed their ash dumps before the rule went into effect, or because they were eligible for an extension, EIP said.

Although groundwater extracted from the monitoring wells showed widespread contamination, the safety of drinking water in nearby wells is not known because power companies are not required to test private wells.

The report’s authors said U.S. coal plants produce about 100 million tons of coal ash annually. For much of the last century, they said, the ash has gone into unlined landfills and waste ponds that were vulnerable to leaks. The majority of the coal plants report unsafe levels of at least four toxic constituents of coal ash, according to the report.

“Many of the coal ash waste ponds are poorly and unsafely designed, with less than 5% having waterproof liners to prevent contaminants from leaking into the groundwater, and 59% built beneath the water table or within 5 feet of it,” the statement said.

In addition, the report notes, the federal Coal Ash Rule does not cover coal ash dumps that have been closed, even though they, too, are polluting groundwater. The report says there are hundreds of these ash dumps across the country.

A trade group representing the coal ash industry contested the findings and said EIP’s interpretation of the monitoring data was faulty.

The top polluter is in Texas

The list of the 10 sites where groundwater pollution was worst included power plants in Texas, North Carolina, Wyoming, Pennsylvania, Tennessee, Maryland, Utah, Mississippi, and Kentucky. Heading the list is the San Miguel Power Plant in Christine, Texas, about an hour south of San Antonio along Interstate 37. The report notes that groundwater near the plant is contaminated with at least 10 pollutants that are leaking from coal ash dumps. They include cadmium and lithium at concentrations more than 100 times what are considered safe.

The 400 MW plant is owned by the San Miguel Electric Cooperative, a member-owned mining and power generating cooperative.

The cooperative’s website devotes several pages to the benefits of coal ash. “Coal ash is king in Texas,” the website says. In a section titled “Coal Ash: Beneficial for Everyday Life,” the cooperative says coal ash has a variety of uses in construction, manufacturing, and environmental remediation. Fly ash, another byproduct of burning coal, is useful for road construction and for making concrete.

The website asserts that the Environmental Protection Agency has classified coal combustion products (CCPs) as non-hazardous.

“The agency made that determination after more than 20 years of study,” the website says. “In fact, it and other federal agencies encourage the use of CCPs and other recycled materials in construction.”

According to the website Ashtracker, the San Miguel plant has 26 groundwater monitoring wells, all of which have been polluted above federal advisory levels. Groundwater contains unsafe levels of lithium, sulfate, boron, beryllium, cobalt, cadmium, thallium, arsenic, selenium, radium, fluoride, mercury, molybdenum, and antimony.

The second and third most polluting plants are, respectively, Duke Energy’s Allen Stream Station in Belmont, North Carolina, and PacifiCorp’s Jim Bridger power plant in Wyoming.

San Miguel responds

Nothing new here, the San Miguel Electric Cooperative said in a written statement to Green Building Advisor. The cooperative said that data the Environmental Integrity Project used in its analysis had already been cited in an earlier report on groundwater contamination.

“As was the case with that report, San Miguel is well aware of the situation, as the data was collected and reported by San Miguel and is posted on San Miguel’s own CCR website,” the statement says.

The cooperative took issue with the report’s  ranking system because it does not recognize that groundwater could be “previously impacted by naturally occurring levels of constituents making it unfit to drink,” as is the case at San Miguel.

“Never in the EIP report does it disclose, recognize or explain that there is no evidence of risk to human health at San Miguel given that the groundwater alleged to be contaminated by CCR units is not used for drinking,” the cooperative said.

The statement adds, “This appears to be an intentional omission, indicating EIP’s clear purpose of triggering fear and suspicion, as opposed to presenting a balanced view of the facts.”

San Miguel said it was conducting all required investigations and that it would take any corrective actions required by law.

The industry says it is fixing the problem

Tom Adams, the executive director of the American Coal Ash Association, a trade group that promotes the recycling of CCPs, said he had not seen the EIP report. He said his organization is focused on recycling, not managing coal ash in landfills and ponds.

He referred questions on that issue to another industry group, the Utility Solid Waste Activities Group.

Jim Roewer, its executive director, said in a telephone call that the EIP report overstates the extent of the problem. The report’s authors interpreted the data differently than the procedure outlined in the federal coal ash rule.

“The evaluation of the data that EIP took is overstating the extent of violation of groundwater protection standards,” Roewer said. “In some cases, they’re pointing to constituents that there aren’t groundwater protection standards for and saying that’s a violation. Well, no, it’s not, under the rule.”

He also said that results of groundwater monitoring don’t necessarily mean that anyone’s drinking water is contaminated.

Roewer said some companies have already started looking at corrective measures, as outlined in the federal rules. “There are impacts out there,” he said. “Those impacts are being addressed by the industry… Any impacts we’re having on groundwater that have been identified as a result of our monitoring program will be addressed as required by the rule.”