Radioactive contaminants found in coal ash

September 2, 2015, Duke University
Hyco Lake, N.C., is a coal ash holding pond. Credit: Duke University

A new Duke University-led study has revealed the presence of radioactive contaminants in coal ash from all three major U.S. coal-producing basins.

The study found that levels of radioactivity in the ash were up to five times higher than in normal soil, and up to 10 times higher than in the parent coal itself because of the way combustion concentrates radioactivity.

The finding raises concerns about the environmental and human health risks posed by , which is currently unregulated and is stored in ' holding ponds and landfills nationwide.

"Until now, metals and contaminants such as selenium and arsenic have been the major known contaminants of concern in coal ash," said Avner Vengosh, professor of geochemistry and water quality at Duke's Nicholas School of the Environment. "This study raises the possibility we should also be looking for radioactive elements, such as radium isotopes and lead-210, and including them in our monitoring efforts."

Radium isotopes and lead-210 occur naturally in coal as chemical by-products of its uranium and thorium content. Vengosh's research team revealed that when the coal is burned, the radium isotopes become concentrated in the coal ash residues, and the lead-210 becomes chemically volatile and reattaches itself to tiny particles of fly ash. This causes additional enrichment of radioactivity in the fly ash.

"Radioactive radium and lead-210 ends up concentrated in these tiny particles of fly ash, which though individually small, collectively comprise the largest volume of coal ash waste going into holding ponds and landfills," said Nancy Lauer, a Ph.D. student in Vengosh's lab who was lead author of the study.

Vengosh, Lauer and their colleagues published their peer-reviewed paper Sept. 2 in the journal Environmental Science & Technology.

The study comes as the U.S. Environmental Protection Agency's first-ever regulations on coal ash disposal are set to go into effect in October.

Currently, coal ash disposal sites are not monitored for radioactivity, Vengosh noted, "so we don't know how much of these contaminants are released to the environment, and how they might affect human health in areas where coal ash ponds and landfills are leaking. Our study opens the door for future evaluation of this potential risk."

Smokestack scrubbers installed at U.S. power plants keep these contaminants from escaping into the air when the coal is burned, he stressed. But if the contaminated coal ash is spilled, or if effluents leak from ponds or landfills, it may pose a hazard.

"Because of the tiny size of the particles, they are much more likely to be suspended in air if they are disposed in a dry form. People breathing this air may face increased risks, particularly since tend to be more enriched in radioactivity," Lauer said.

Vengosh said this study is the first systematic study to compare radioactivity in coal and coal ash from the Illinois, Appalachian and Powder River basins. The researchers collected multiple samples of coal and coal ash from all three coal-producing basins and then measured the radioactive elements in each sample.

Their tests showed that coal and coal ash from different basins exhibited different levels of radioactivity - the Illinois basin had the most, followed by the Appalachian and then the Powder River, which is in Wyoming and Montana. The tests also showed that the ratio of radium to uranium in the parent coal was consistent with the ratio found in its residual coal ash.

"This means we can predict how much potential radioactivity will occur in coal ash by measuring the uranium content in the parent coal, which is easily discerned," Vengosh said. "This analysis can be applied to all coal ash worldwide, and is useful information for regulators, industries and scientists alike."

Because the isotopic ratios of the coal and coal ash varied between basins but were consistent within each individual basin, researchers can also use them to determine the source of environmental contamination. "They allow us to not only distinguish between the three basins, but also to determine whether contaminants are coming from coal ash or some other naturally occurring source in the local environment," Lauer said.

Explore further: New tracers can identify coal ash contamination in water

More information: "Naturally Occurring Radioactive Materials in Coals and Coal Combustion Residuals in the United States," Nancy E. Lauer, James C. Hower, Heileen Hsu-Kim, Ross K. Taggart, Avner Vengosh. Environmental Science & Technology, Sept. 2, 2015. DOI:

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1.8 / 5 (16) Sep 02, 2015
Slow, agonizing death from cancers is just one of the hallmarks of radiation. Genetic mutations also are caused by radiated DNA. Look up the Children of Chernobyl, if you can take it.

Nukes and coal are killing us, and threatening the safety and health of all our descendants, since much of this nasty stuff lasts forever in Human terms.

How can their supporters face themselves?
1.5 / 5 (15) Sep 02, 2015
Some utilities, such as Duke, have taken responsibility for their decades of coal use, and are making good strides in cleaning it up. It is an impressive utility.
Sep 02, 2015
This comment has been removed by a moderator.
2.6 / 5 (5) Sep 02, 2015
What would happen if you built your home right on top of a pile of coal ash? Your total yearly exposure to radiation would increase by about 20%. Big Deal! Normal every day radon levels are a much bigger problem.

5 / 5 (6) Sep 02, 2015
Says something about the change in views when you can actually do such studies of King Coal's pollution, never mind publish...
3.5 / 5 (11) Sep 02, 2015
Yawn. Coal ash has all sorts of interesting stuff in it. The radioactivity has been known for many decades. It should not be a surprise to anyone.

Do note: many well water supplies have naturally occurring radium and uranium. Filters have been developed to take out those contaminants.

Like many things, radioactivity rises and sets with the sun every day. Safety is a matter of degree. Five times a very small number is still a small number, though perhaps a number worth paying more attention to. Remember that we're dealing with a logarithmic scale here, not a linear one.
2.1 / 5 (14) Sep 02, 2015
Nik, I'm waiting for the trial of Don Blankenship, who ran his workers to death, essentially.
1.6 / 5 (7) Sep 02, 2015
ab3a, yes, The EPA even considered a rule making for radionucleotide emissions at coal fired power plants.
4.6 / 5 (9) Sep 02, 2015
NoTennisNow: That's one of the funny things I point out about nuclear power: More radiation goes up the stack of a coal fired power plant than you'll ever see coming out of a nuclear reactor.

I'm not belittling this hazard, but we do need to consider it in context of other risks. I'm far more concerned about the sulfur dioxide than I am about a slight amount of radium that one may detect going up the stack.

In fact, coal ash may prove quite lucrative if someone were ever to find a way to safely and inexpensively extract the heavy metals from it.
1.3 / 5 (13) Sep 02, 2015
"In fact, coal ash may prove quite lucrative if someone were ever to find a way to safely and inexpensively extract the heavy metals from it."
Exactly right. Meantime, it is a toxic nuisance. But whoever has it for a few years might just turn that liability to an asset.
1.5 / 5 (8) Sep 02, 2015
ab3a: my consulting career was with the coal fired power industry. Mostly related to comments on proposed EPA SO2 control stuff. I used to have a file folder with stuff about radioactivity in fly ash. Since I retired it is either buried in a box somewhere of lost to history.
2.6 / 5 (5) Sep 03, 2015
This article is a prime example of taking a true fact and distorting it so as to become an apocalyptic worry. OMG 5x normal radiation levels we are all going to die. 5x very very little is still very little.
2.3 / 5 (9) Sep 03, 2015
Coal ash disposal is a big issue in NC. We had a leak of a fly ash retention pond into a river. Duke Energy, the NC Department of Environment and Natural Resources (DENR) and the courts had a big "dustup" (pun intended).
1.3 / 5 (13) Sep 03, 2015
NoTennis, I am repeatedly surprised at the forward-looking management at Duke. They seem to have thrown themselves into cleaning up their act professionally.
1 / 5 (6) Sep 03, 2015
MR66: So far so good.
Uncle Ira
4.4 / 5 (13) Sep 03, 2015
NoTennis, I am repeatedly surprised at the forward-looking management at Duke. They seem to have thrown themselves into cleaning up their act professionally.

Cher, if you would try the Google-Skippy every now and then, you would see that the Duke-Skippys had to be dragged kicking and screaming into doing something about it and are still resisting doing all that they should. PLEASE change sides, you are really not helping any of the causes you slogan on.
1.6 / 5 (7) Sep 03, 2015
nkalanaga: Thanks for the post. I believe this was the reference that I used as part of my work.
not rated yet Sep 03, 2015
I am sure that the Duke Energy study isn't going to cause the EPA to modify its regulations regarding coal ash but in 19 enough for other studies at the University level to be conducted into how safe it is to be living near coal ash pits, or even to use products which are made from recycled coal ash.
4.2 / 5 (10) Sep 03, 2015
NoTennis, I am repeatedly surprised at the forward-looking management at Duke. They seem to have thrown themselves into cleaning up their act professionally.
Sad. Another lie which ira exposed in only a few minutes.
1 / 5 (11) Sep 04, 2015
They have been mining the Mountain View dump for decades.
1 / 5 (6) Sep 04, 2015
I believe that there are at least two dockets created by EPA in support of rule making (proposed rules) for radionuclide enissions from Fossil Fuel Fired Electric Utility Steam Generators,one in the early 80"s (late 70' s?), and one much more recent (around 2010 or so).
1.8 / 5 (5) Sep 05, 2015
Slow, agonizing death from cancers is just one of the hallmarks of radiation. Genetic mutations also are caused by radiated DNA.
Wind/solar is much more dangerous, it uses rare-earth metals that contain traces of radioactive uranium and thorium.
1 / 5 (10) Sep 05, 2015
" it uses rare-earth metals that contain traces of radioactive uranium and thorium."

Yes. "traces" of, not substantial parts of, compared to hundreds of tons of intensely-radioactive materials we get from nuclear powerplants each fuel cycle.
2.3 / 5 (9) Sep 05, 2015
Also, granite can emit Radon gas. So, radionuclides are sll over the place.
1 / 5 (7) Sep 05, 2015
If that is bad then so is the Iran "Deal".
1.6 / 5 (13) Sep 05, 2015
"If that is bad then so is the Iran "Deal"."

We are really sorry to take away your right to another Republican Religious War.

But you haven't paid for the last several.
2.1 / 5 (7) Sep 05, 2015
What is so new here? It's been known for decades that coal plants produce more radiation that a properly operated nuclear plant.

Sorry, gkam, that was supposed to be "5". Duh, me.
2.5 / 5 (11) Sep 05, 2015
Slow, agonizing death from cancers is just one of the hallmarks of radiation. Genetic mutations also are caused by radiated DNA. Look up the Children of Chernobyl, if you can take it.

Hysteria has caused more mortality and morbidity in the Chernobyl area than the radiation did. The radiation is not innocuous, but that was an accident. The fear mongering is deliberate.
1.6 / 5 (7) Sep 05, 2015
hundreds of tons of intensely-radioactive materials we get from nuclear powerplants
It is already well known that all waste containers cover a plot of land the size of a football field.
"To put this in perspective, if we were to take all the nuclear waste produced to date in the United States and stack it side-by-side, end-to-end, it would cover an area about the size of a football field to a depth of about thirty feet."

While construction of a 25-turbine wind facility clears enough trees to fill 100 football fields; 4-6 acres of forest is clearcut for each turbine.
Furthermore, " ton of rare earth minerals produces about one ton of radioactive waste.."
2 / 5 (8) Sep 05, 2015
Thorium is the major contaminate in rare earth bearing minerals.
2.3 / 5 (9) Sep 05, 2015
"There ain't no free lunch"
2 / 5 (4) Sep 06, 2015
I'd like to see a source for that.
"Rare Earth .. come mixed with the slightly radioactive thorium."
"..11,000 truckloads of radioactively contaminated material.."
"The ore tends to carry uranium and thorium, the most radioactive element on the planet.."
"..but also radioactive elements such as thorium which, if ingested, cause cancers of the pancreas and lungs, and leukaemia."
Wind/solar pollutes much more than nuclear.
1.4 / 5 (11) Sep 06, 2015
"Wind/solar pollutes much more than nuclear."

Really? I do not see any long-term cleanup at Altamont.

Now, let's look at Fukushima and Chernobyl, and some of the weapons sites. All nuclear technology is dangerous.
2.6 / 5 (10) Sep 06, 2015
Ok, how many Bequerels for these wasts?
1.4 / 5 (11) Sep 06, 2015
It depends on what you are measuring and where.

Go to Fukushima Diary and see the reports from TEPCO and the other sources.

or go to:

Both are news aggregators, with the sources listed.
1 / 5 (10) Sep 06, 2015
NoTennis, if you looked into the condition of our weapons materials waste, you would have a hard time believing we could do that to the Earth, . . and ourselves.
2 / 5 (4) Sep 06, 2015
Both are news aggregators, with the sources listed.
Both are scaremonger websites; they induce abortions, heart-attacks, anxiety/agony, suicides, by spreading irrational fear on civilian population through myths/beliefs and fictional data. They provoke more deaths than radiation.
1 / 5 (11) Sep 06, 2015
Wilie is right. You don't want to die of fright, do you?

We should just buck up, go to Fukushima, . . . and walk into the glow.

2.8 / 5 (6) Sep 06, 2015
So, is there any method of generating commercial quantities of electricity that are acceptable?
nuclear is proven to generate commercial quantities of electricity with fewer fatalities and less environmental impacts than renewables. Death/TWh: Solar 0.44 , Wind 0.15, Hydro 0.10, Nuclear 0.04; nuclear is safer than solar, wind and hydro.
5 / 5 (3) Sep 06, 2015
This is so not only not news, and more 'same old wine in new bottles'! When I was in civil engineer school in Sacramento in the mid know, when velociraptors roamed the earth, one of my profs stated his opinion about coal. Dr Post called it a 'garbage can' of all kinds of problem substances. That included radium, the stuff they painted watch face numbers with in the bad old days of ignorance=bliss=1926, etc...and killed many of the painters in later life.

When you think of it, what is coal but the sum of all the offal, shit, pee, rotten veggies, putrid bodies, and other organic material that ever fell to the ground and rotted away...or fossilized...; and was covered up with more layers..rinse, lather, repeat for eons until some event covered the whole layer. But of course that was only for ONE coal seam from land deposition. Earth the serial changer soon had many more in the space of geologic time.
As new generations are not told of past sins, we repeat them!!
4 / 5 (4) Sep 06, 2015
Heeyyyy GKam, coal ash is used now. It is in every re-inforced concrete structure as part of the concrete add mix. Some have called it the 'new pozzolan'. I will leave it to your limited intellect to look that up. Mean while try to avoid welfare offices when you go to get your checks and EBT cards. Most of them are concrete as well. Some quite artistic and designed by Frank Lloyd Wright. That last fella is an old 'fart' who left us many years ago God rest his creative soul. You can look him up too, or go to Florida Southern University and see his work first hand.
2.5 / 5 (8) Sep 06, 2015
WillieWard: Are you trying to equate thorium and un-enriched uranium with reprocessing waste?

If you (or anyone else) want to really worry, look up the term Banna Equivalent Dose:

"Is an informal expression of ionizing radiation exposure, intended as a general educational example to indicate the potential dose due to naturally occurring radioactive isotopes by eating one average-sized banana. One BED is often taken as 0.1 µSv, however, in practice this dose is not cumulative, as the principal radioactive component is excreted to maintain metabolic equilibrium. The BED is only an indicative concept meant to show the existence of very low levels of natural radioactivity within a natural food and is not a formally adopted dose quantity".
1 / 5 (9) Sep 06, 2015
Gosh, Osiris, what will they think of next, except they thought of all that decades ago, so you are not telling anybody anything, Go look that up when you go back to school.
2 / 5 (4) Sep 07, 2015
Coal fly ash is sprayed out in Chemtrails to block solar radiation and offset global warming.

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