Tag Archives: Coal ash

Dominion Tweaks Coal-Ash Dewatering Process

Coal ash pond at Possum Point Power Station.

Coal ash pond at Possum Point. Photo credit: Prince William Times and Potomac Riverkeepers Network.

Dominion Virginia Power has temporarily shut down the $35 million water treatment facility at its Possum Point Power Station as it adjusts the process of cleaning water from its coal ash ponds,

Levels of selenium, a chemical element that can be toxic at high levels, rose above a “trigger” point specified in agreement between Dominion and Prince William County, reported the Prince William Times. However, Dominion was never in violation of its water quality permit, which requires the company to test treated water for selenium and a dozen other coal-ash contaminants.

Dominion officials attribute the pause in de-watering the coal ash ponds to “lessons learned” from operational challenges at Possum Point. Changes detailed in a revised engineering report, which must be approved by state and county officials, should result in discharges of selenium and zinc even lower than called for in the water permit. Also, the water-treatment facility should operate more efficiently.

“We decided to stop, redesign and update,” Jason Williams, environmental manager, told Bacon’s Rebellion. The company plans to switch from a geotube technology to clarifiers and settling tanks like the system in operation at the Bremo Power Station, he said. Also, by adding two more water-holding tanks like at Bremo, there will be less stop-and-go in the water discharge. “It will be much more efficient than firing up the system, waiting for test data, and discharging.”

Dewatering should resume early next year, pending regulatory approvals.

Possum Point De-watering Permit Upheld

Possum Point coal ash ponds

Possum Point coal ash ponds

A Richmond Circuit Court judge has upheld the state’s issuance of a water-discharge permit for Dominion Virginia Power’s coal ash pond at the Possum Creek Power Station.

The permit sets the effluent limits and monitoring requirements for the discharge of water from coal ash Pond D. The Potomac Riverkeepers Network had challenged the permit on two main grounds: (1) that the Department of Environmental Quality (DEQ) had failed to conduct an analysis of the best available technology to control the release of toxic compounds; and (2) that the discharge of “metals-laden” waste-water into the Quantico Creek added to the impairment of the creek in violation of the Clean Water Act.

Judge Beverly W. Snukals ruled that state regulators followed the law in issuing the permit. Also, she wrote, “DEQ had substantial evidence in its record to support its conclusion that the Permit protects existing instream water uses in Quantico Creek.”

Dominion is pleased with the court’s ruling, said Dominion spokesman Bob Richardson. “We’ve worked hard to design a system that treats the water better than the stringent limits set by DEQ and we prove our commitment to the environment everyday as we do the work required to safely close ash ponds at Possum Point and across our fleet.”

“We are still in the process of reviewing the Court’s opinion, but we are disappointed with the outcome,” said Greg Buppert, senior attorney with the Southern Environmental Law Center, which is representing the Potomac Riverkeepers. “We strongly believe Quantico Creek and the Potomac River deserve the highest level of protection from Dominion’s decades of coal ash contamination at Possum Point.”


Hexavalent Chromium May Be Endemic in Piedmont Well Water

hexavalent-chromiumby James A. Bacon

Hexavalent chromium, a potent carcinogen, is detectable in 90% of the North Carolina water wells sampled in a Duke University research study, and in many cases exceeds levels deemed safe for drinking water.

The chemical, made famous by the movie “Erin Brockovich,” originates not from coal ash ponds but from the natural leaching of mostly volcanic rock in aquifers across the Piedmont region, said Avner Vengosh, professor of geochemistry and water quality at Duke’s Nicholas School of the Environment in a press release issued yesterday.

Piedmont formations with volcanic rocks are common across the southeastern United States, Vengosh noted, so millions of people in regions outside North Carolina with similar aquifers may be exposed to hexavalent chromium without knowing it. Vengosh published his findings Oct. 26 in the peer-reviewed journal Environmental Science and Technology Letters.

The controversy over hexavalent chromium has roiled politics in North Carolina. In 2015 the state’s water-quality officials issued temporary “do not drink” recommendations to residents living near coal-burning plants after tests detected potentially harmful levels of hexavalent chromium in their well water samples. Because elevated levels of chromium typically occur in coal ash, many people assumed the contamination was linked to the coal ash ponds. The Vengosh study, states the Duke press release, is the first to show otherwise.

A similar controversy has raged in Virginia where the compound has been detected in well water of homes near the Bremo Power Station and the Possum Point Power Station where Dominion Virginia Power is de-watering coal ash ponds and has applied for permits to cap the dried coal-combustion residue in place.

The Duke study undoubtedly will change the tenor of the coal ash debate in Virginia, whose Piedmont geology is similar to North Carolina’s. The Duke findings are consistent with Dominion’s contention that the hexavalent chromium found in wells did not originate from its coal ash ponds. Dominion’s own measurements had indicated no such groundwater impact.

But controversy over coal ash disposal will not go away. Tests by the Potomac Riverkeeper Network have found elevated levels of lead in wells near the Possum Point coal ash ponds and also have detected potentially toxic levels of other heavy metals found in coal ash. However, Virginia Department of Environmental Quality tests have not replicated the results.

Meanwhile, the Duke findings raise issues about the safety of well water generally. Speaking about the situation in North Carolina, Vengosh said: “The bottom line is that we need to protect the health of North Carolinians from the naturally occurring threat of hexavalent chromium, while also protecting them from harmful contaminants such as arsenic and selenium, which our previous research has shown do derive from leaking coal ash ponds. The impact of leaking coal ash ponds on water resources is still a major environmental issue.”

Bacon’s bottom line: Hopefully, Vengosh’s findings will elevate the discussion about coal ash in Virginia. The most important takeaway is this: Just because a particular chemical is found in both in coal ash and the water from nearby wells, we cannot assume that the chemical necessarily came from the coal ash. Underground aquifers contain many chemicals that have leached from naturally occurring rocks and minerals. Nature is not pristine. Underground water is not as pure as distilled water. When we start measuring water quality in parts per billion, we will find all sorts of compounds we never imagined were there.

Conversely, just because hexavelent chromium occurs in natural conditions, we cannot assume by analogy that lead, selenium, arsenic or other chemicals found in well water near coal ash ponds are naturally occurring as well. We just don’t know. We need to conduct more comprehensive testing before making multi-billion dollar decisions on the best way to dispose of coal ash and/or commit ourselves to remedies that we (and our descendants) have to live with for hundreds of years.

The Economics of Coal Ash Disposal

A trucks hauls coal ash from a retention pond to a permanent pond at Domiion's Possum Point Power Station. Photo credit: AP

A truck hauls coal ash from a retention pond to a permanent pond at Dominion’s Possum Point Power Station. Photo credit: AP

To cap coal ash pits in existing locations or to haul it off to landfills is the multibillion dollar question facing the electric utility industry.

by James A. Bacon

The debate over coal ash hasn’t gone away — it’s just morphed. For much of the year, public attention focused on how to de-water millions of tons of coal-combustion residue that utilities and industrial companies accumulated over decades in large retaining ponds. Discussion centered on how to ensure that the water released into rivers and streams did no harm to aquatic life and human health. Now attention is turning to what to do with coal ash once it’s dry.

The October 17 deadline is fast approaching for industrial-scale coal burners to file written closure plans for their coal ash ponds. Each company must choose whether to go with the “closure-in-place” option or the removal option. Closure in place could spare ratepayers billions of dollars in added costs, but “removal” could reduce long-term health risks from potentially toxic metals that could leach from the coal ash pits into the groundwater and, from there, into rivers and streams.

Here in Virginia, Dominion Virginia Power has laid out plans to consolidate coal ash on-site at its power stations, and to cap the material with an impermeable plastic lining and vegetation to prevent rainwater from percolating through. Environmentalists say that won’t prevent groundwater from migrating through the ponds and picking up heavy metals in the process. As evidence, they point to water quality tests that show elevated levels of metals appearing in locations outside Dominion’s facilities. Clouding the matter, however, the state Department of Environmental Quality says that its tests show contradictory results.

In a recent conference call with media, Jim Roewer, executive director of the Utility Solid Waste Activities Group, emphasized the high cost of transporting the ash to lined landfills, as environmental groups have called for. In an informal survey early in the regulatory process, he said, four out of five utilities said they expected to go with the closure-in-place option. That preference reflected the economics of coal ash disposal at their particular locations. A June Tennessee Valley Authority study concludes that it would cost about $280 million to close its six coal-ash sites using closure-in-place but $2.7 billion using the cheapest combination of truck and train — almost ten times as much.

Dominion has said that the tab for the removal option could run the clean-up cost to as much as $3 billion. Virginia environmental groups have pointed to decisions by Duke Energy, Santee Cooper, and SG&E in the Carolinas to transport the coal ash to landfills, arguing that Virginia citizens should have no less protection from exposure to toxic levels of chemicals than those of North and South Carolina.

Roewer argues that the economics of closure-in-place versus removal vary widely from site to site. While removal may be an economically viable option in some locations, it is far more expensive in others. Trucking coal ash long distances is economically impractical. While most coal-fired power plants are served by railroads, that doesn’t mean it’s simple to load the ash into trains for shipment to landfills. The rail lines were designed to dump coal at the station; loading facilities would have to be constructed at considerable cost to load the ash onto trains. Unless the landfill were located directly on the rail line, the other end of the line also would require another facility to unload the coal ash onto trucks for the short haul to the landfill.

Environmentalists suggest that recycling the gritty coal ash into cinderblocks or other products could reduce the need to dispose of so much ash. “Recycling of coal ash … costs far less than excavation and removal,” says Brad McLane, a Southern Environmental Law Center (SELC) attorney who has represented the James River Association in coal ash litigation. “This is happening at the Winyah plant in South Carolina and is being performed by the Southeastern Fly Ash Association. Coal ash recycling may not be feasible everywhere, but where it is feasible, it is a win-win solution.”

Recycling coal ash tends to be most feasible in large metropolitan areas where a third party enjoys a big enough market to justify building a dedicated recycling facility. Dominion has ruled out that option for its rural Bremo Power Station. In urban areas, obtaining the needed permits to build a recycling plant could add years to the disposal process. And any solution that entails trucking large volumes of coal ash through residential areas, as would be the case with Dominion’s Possum Point Power Station, poses problems of its own.

But McLane also questions Roewer’s estimate that four out of five power stations will pursue closure-in-place. “That is not consistent with our experience in our region.  All sites in South Carolina are being excavated, and more than half of the sites in North Carolina are being excavated, with review still occurring regarding the long-term approach for the remaining sites in North Carolina.”

Moreover, Roewer is not considering some of the costs and risks associated with closure-in-place, McLane says. The Environmental Protection Agency’s Coal Combustion Residue (CCR) rule generally provides for only 30 years of post-closure care, but coal ash pits, some of which in Virginia are located near low-lying waterways, will incur “the risk of catastrophic failure over the millennia” to sea level rise and increased storm intensity as a result of climate change.

EPA’s risk assessment looks at the risk of coal ash leaching over a 5,000-year period. If heavy metals do leach into the groundwater and contaminate surface waters after 30 years, additional measures will be required to address the pollution, McLane says. “Utilities may end up needing to go back and excavate these sites years in the future to comply with the CCR rule after having wasted money on half measures that will not work. Why not do the right thing from the start?

Bacon’s Rebellion asked Dominion for input to this story but, preoccupied with hurricane preparations, the company was unable to respond.

Maryland Drops Coal Ash Appeal

The coal ash ponds at Possum Point

The coal ash ponds at Possum Point

The state of Maryland has dropped its appeal of permits granted to Dominion Virginia Power for discharging treated water from its Possum Point Power Station coal ash ponds into Quantico Creek and the Potomac River.

“Maryland is supportive of recent agreements in Virginia to increase wastewater treatment protections and monitoring protocols,” Ben Grumbles, Maryland’s secretary of the environment, said in a statement. “We are engaged in and encouraged by the ongoing discussions with Virginia and Dominion to do even more testing for fish tissue, water quality and sediment in the river beyond the current testing and monitoring in current or soon-to-be-proposed permits.”

Jay Apperson, a spokesman for the department, cited Dominion’s commitments to enhanced treatment of the water drawn from coal ash ponds and to specifications that meet or exceed Maryland’s water quality standards, reports the Richmond Times-Dispatch. He continued:

Moreover, Virginia DEQ has pledged to draft a stringent and comprehensive solid waste permit for the Dominion facility that incorporates all federal requirements. Virginia DEQ has further discussed its intent to engage Maryland during this permitting process as groundwater monitoring and surface water monitoring safeguards are included to protect Quantico Creek and the Potomac River.

The only group persisting in an appeal of the coal ash water-discharge permits is the Potomac Riverkeeper Network.

Bacon’s bottom line: The big remaining issue is how Dominion will dispose of the coal ash itself. Dominion has applied for permits to consolidate the material in capped pits on-site, asserting that the alternative preferred by environmentalists — trucking it to lined landfills — would cost $3 billion more. The statements from Maryland’s Department of the Environment suggests that Maryland has taken part in intensive, behind-the-scenes negotiations with Virginia DEQ, as Virginia regulators decide whether to grant the solid waste permits or not.


Duke Study Documents Coal Ash Leakage into Groundwater

Graphic credit: Environmental Science and Technology

Graphic credit: Environmental Science and Technology

by James A. Bacon

New tests and analysis conducted by Duke University add to the body of evidence indicating that heavy metals in coal ash ponds leach into the water and and make their way into surrounding water, sometimes in excess of federal standards for drinking water and aquatic life.

The researchers sampled surface water near seven coal ash pits and seeps from berms ringing the unlined ponds at seven sites in four states, including Dominion Virginia Power’s Bremo and Chesapeake power stations, and combined it with data from 156 shallow groundwater monitoring wells in North Carolina. The scientists used “forensic tracers” — isotopes of boron and strontium created in coal combustion and not found in a natural environment — to track the movement of metals from the coal ash ponds to nearby waters.

The research, which was funded by the Southern Environmental Law Center, appeared in Environmental Science and Technology, a peer-reviewed journal.

Read the study here. And read the more-comprehensible-to-the-layman coverage by the Richmond Times-Dispatch here. Writes Robert Zullo with the T-D:

At Bremo, samples were taken from Holman Creek, a leak from the ash pond wall that was running toward the river and the river itself downstream of the power plant. … One test, for example, showed arsenic at a concentration of 45.4 parts per billion, more than 45 times background levels and 4.5 times the federal Environmental Protection Agency drinking water maximum contaminant level of 10 parts per billion. Another test showed arsenic at 10.7 parts per billion.

Bacon’s bottom line: Coal Combustion Residuals, of which coal ash is one type, is the largest source of industrial waste in the United States. Yet the processes by which leachate from the coal residue works its way into surrounding waters appears not to be terribly well understood. The federal government has ordered a particular set of remedies — treat and drain the water, then cap or landfill the mineral residue — in what appears to be a state of imperfect knowledge. State governments have the authority to exceed federal standards, which environmental groups are pressing them to do. They are dealing with the same imperfect knowledge.

When the water is drained from the coal ash, the next question is what to do with the mineral residue. Dominion proposes consolidating the material on site and capping it to prevent rainwater from seeping through. Environmental groups, concerned that groundwater migrating through the ash pits could contaminate nearby waters, want Dominion to dispose of it in lined landfills — a process that Dominion says could cost rate payers $3 billion.

The Duke study is potentially important because, as the authors write in their abstract, “Given the large number of coal ash impoundments throughout the United States, the systematic evidence for leaking of coal ash ponds shown in this study highlights potential environmental risks from unlined coal ash ponds.”

We’re talking about what could be a genuine problem here in Virginia. We can quantify the very real, $3 billion cost of disposing of the coal ash in lined landfills, but it is exceedingly difficult to put a dollar value on the risk to human and aquatic life posed by leaving the mineral in capped but unlined pits. I’m not sure how we go about even conducting that analysis. I would like to think that any regulatory decisions are made after rigorous study and thought. But that’s probably too much to ask in a world in which political decisions are made under time pressure on the basis of ideology and self-interest.

Coal Ash, Parts Per Billion, and Risk


Coal ash ponds at Possum Point before Dominion Virginia Power started draining the ponds and consolidating the coal ash.

Kudos to Robert Zullo with the Richmond Times-Dispatch for digging beneath the dueling press releases to shed light on the contamination risks that coal ash ponds pose to drinking water. Focusing on the carcinogenic chemical hexavalent chromium, which has been detected in well water near Dominion Virginia Power’s Possum Point Power Station, he broaches key questions: How much of the chemical is too much? What level should the state permit?

Other questions he touched upon in passing: If hexavalent chromium exists in well water, how did it get there? Did it come from the coal ash ponds, or does it occur naturally in minute quantities?

The Environmental Protection Agency (EPA) sets a drinking-water standard of 100 parts per billion for chromium, which Virginia’s Department of Environmental Quality (DEQ) has adopted as its own standard. However, hexavalent chromium is widely regarded as a more dangerous version of the metal. California has set a separate limit of 10 parts per billion for drinking water for that compound, Zullo reports, reflecting a balance between health risks and the cost to water utilities of meeting the level.

Dealing with its own coal ash problem, the state of North Carolina conducted tests last year of well water within 1,500 feet of coal ash basins, using a standard of 0.07 parts per billion, which it determined was associated with a “potential one-in-a-million cancer risk for an average person drinking this water over an average lifetime.” Tarheel regulators issued several hundred “do not drink” letters to private well owners last year. Critics contended that the 0.07 parts-per-billion level was so strict that even municipal water systems could not meet it, and the state reversed course, telling residents that their well water was “just as safe as the majority of public water supplies in the country.”

The issue surfaced in Virginia when DEQ tested seven private wells near Possum Point and found hexavalent chromium in one — 5 parts per billion, right at the state’s reporting limit. The Southern Environmental Law Center (SELC) commissioned other tests and found another house where the chemical was found at a 1.2 parts-per-billion level.

SELC argues that DEQ should use testing methods that identify the chemical at levels lower than its 5 parts-per-billion standard. Said Greg Buppert, an SELC attorney: “This is a human carcinogen and we should be looking at it at lower concentrations, because we know it’s a concern.”

Bacon’s bottom line: What we’re talking about here is measuring minutes quantities of hexavalent chromium and parsing minute risks. From my (admittedly primitive) understanding, there is no known level above which a given chemical in the drinking water is dangerous and below which it is “safe.” We’re dealing with a continuum in which the statistical risk diminishes with smaller concentrations of the chemical. North Carolina’s level of 0.07 poses a risk of one-in-a-million people getting cancer after a lifetime of drinking the water. That’s crazily low. Even if hundreds of households drank the well water for years, the odds are remote that a single person would get cancer from the chemical.

One must balance that against the cost of eliminating that risk, which in Dominion’s service territory could approach $3 billion. If Virginia rate payers kept that money, what would they do with the money? Presumably, they would spend it on other things. Sure, they might buy a bigger house or purchase more movie tickets. But they also might purchase safer cars, have more frequent medical check-ups, eat healthier food, or join a health club. When we take money from people, whether through taxes or regulation, we fail to take into account the fact that we deprive them of the means to mitigate every-day risks to their health and safety.

Life is full of risks but we as a society say we can live with them. The Virginian-Pilot reports today on a fluke accident in which a beach umbrella on Virginia Beach was blown loose from its moorings in the sand and struck a woman, killing her. Should we ban beach umbrellas to offset the risk of umbrella impalements?

On the other hand, Virginia’s legal limit for hexavalent chromium is more than 100 times North Carolina’s one-in-a-million level. Assuming a straight-line correlation between the hexavalent chromium level and the risk it poses, that implies a one-in-ten-thousand risk or greater for Virginians drinking contaminated well water. That sounds like enough risk to justify having a conversation. Continue reading

Coal Ash to Cold Cash?

There's gold in them thar ponds! Well, not gold, but rare earth elements.

There’s gold in them thar ponds! Well, not gold, but rare earth elements.

by James A. Bacon

A Duke University study of coal ash has found that the mineral residue from coal combustion contains high concentrations of valuable rare-earth elements neodymium, europium, terbium, dysprosium, yttrium and erbium used in uses as varied as cell phones, rechargeable batteries, fluorescent lighting, air pollution controls, and night-vision goggles.

Demand for the exotic elements has exploded in recent years. While no rarer than metals such as chromium, nickel or zinc in the earth’s surface, they are rarely found in extractable concentrations. In 2010 China, which produced 95% of the world’s supply of rare earth elements, restricted exports, sending prices shooting higher and prompting a search for alternate sources of supply.

“The Department of Energy is investing $20 million into research on extraction technologies for coal wastes, and there is literally billions of dollars’ worth of rare earth elements contained in our nation’s coal ash,” said Heileen Hsu-Kim, a professor of civil and environmental engineering at Duke, as quoted in Science Daily.

Researchers studied coal ash samples from power plants located mostly in the Midwest that burn coal sources from all over the country. Analysis showed that ash collected from the Appalachian Mountains has the highest concentration of rare earth elements at 591 parts per billion. However, Appalachian ash is harder to extract, perhaps because it is more likely to be encapsulated within a glassy matrix of aluminum silicates.

“The reagents we used are probably too expensive to use on an industrial scale, but there are many similar chemicals,” said Hsu-Kim. “The trick will be exploring our options and developing technologies to drive the costs down. That way we can tap into this vast resource that is currently just sitting around in disposal ponds.”

Bacon’s bottom line: The next big environmental debate over coal ash is over how to dispose of the ash once it is de-watered. Dominion Virginia Power and many other power companies say it is cheaper to consolidate the material in compounds capped to prevent rainwater from percolating through. But environmentalists would like to see the coal ash disposed in landfills with heavy plastic lining that eliminates any risk of groundwater contamination.

Will the Duke University finding change power company calculations? If a given power station’s coal ash potentially contained a hundred million dollars worth of rare earth metals, would a power company be more likely to hang on to the material for future extraction? Who knows — the world works in strange and unpredictable ways.