Unearthed at the Hanford Site: a bottle, containing Pu-239, dating to 1946. Image credit: Washington Closure.
Way back in 2004, workers began carefully excavating several burial grounds near the Hanford Site’s 300 Area. One of their discoveries had the feel of an archeological find:
A safe was encountered during the excavation of the 618-2 Burial Ground that contained a very pure form of Plutonium-239 on the interior surfaces and possibly in various liquids contained in the safe. The safe appears to be legacy waste from research performed in the 1940s. A metal beaker containing plutonium residue (with high Pu/Am concentration) was also uncovered in the stockpiles of waste from the 618-2 excavation.
That find, and a number of other contaminated bits and pieces, made the news; you can see more photos of the safe and its contents here.
It was yet another reminder to the public that the Cold War legacy is more than nuclear arsenals and treaties; there’s a significant, extremely complex environmental legacy as well.
Hanford’s plutonium problems, in particular, aren’t just limited to old, leaky tanks full of plutonium processing waste. During the Cold War years, a lot of contaminated equipment and other solid waste was buried at the Hanford Site, and many of the earliest records of what was buried at the site are incomplete. Liquid waste was also discharged to the soil. In summary, it’s a difficult, dangerous remediation task.
This all leads me to a recent New York Times article by Matthew Wald that bothered me, for a number of reasons.
All The News That’s Fit To Print?
The Wald article deals with a paper which will be published “later this year” claiming that the Department of Energy’s assessment of underground plutonium at Hanford is far less than what is really there:
The amount of plutonium buried at the Hanford Nuclear Reservation in Washington State is nearly three times what the federal government previously reported, a new analysis indicates, suggesting that a cleanup to protect future generations will be far more challenging than planners had assumed.
Plutonium waste is much more prevalent around nuclear weapons sites nationwide than the Energy Department’s official accounting indicates, said Robert Alvarez [of the Institute for Policy Studies], a former department official who in recent months reanalyzed studies conducted by the department in the last 15 years for Hanford; the Idaho National Engineering Laboratory; the Savannah River Site, near Aiken, S.C.; and elsewhere.
Okay, that sounds fascinating and dramatic, and like there’s definitely cause for concern. It goes on to give some background, explaining that Hanford has the most plutonium contamination of any DOE site, that the danger of it reaching the vadose zone and the Columbia River is why all of this is worrying, and that if there’s so much more plutonium contamination than previously thought, it’ll take longer to clean it up. If you keep reading, you find that Alvarez has compared numbers released by the DOE in 1996 to more recent DOE reports, and has drawn his conclusions from that comparison.
There’s also a bit of hyperbole, like the activist who claims that drinking water will be so contaminated with plutonium in a few hundred years that “We’re going to be killing people, pure and simple.” and then “Mr. Alvarez’s estimate indicates that enough plutonium is buried at Hanford to create 1,800 Nagasaki-size bombs…”.
None of this is helpful, or accurate. Let me explain.
The article mentions that the Alvarez paper “has been accepted for publication later this year”. In other words, the author of the New York Times article is asking us to just believe everything he’s written, when we have absolutely no way to verify it, since Alvarez’s paper hasn’t even been published yet. Additionally, the article doesn’t make it clear that though much of the plutonium may be bomb-grade (plutonium-239), it’s all contamination, not pure, metallic, ready-for-prime-time-use-in-a-bomb plutonium. The bit about “1,800 Nagasaki-sized bombs” is just not relevant.
The Paper: Assumptions, Approximations, and Inaccuracies
What I did find, after a lot of digging and some leads from friends, is that Alvarez’s paper is available online. When the New York Times article first came out, Alvarez’s paper (pdf) was not easy to find, but he sent it to the Blue Ribbon Commission on America’s Nuclear Future prior to their visit to the Hanford Site, along with a letter (pdf) indicating that this, indeed, is the same paper that will be published later this year. (He has since posted his paper on the Institute for Policy Studies website.)
What immediately jumps out at me is that the author of the New York Times article either didn’t read the paper, or willfully exaggerated what it says. The paper actually says the DOE overall has three times more underground plutonium contamination than previously thought, and that Hanford may have twice as much as previously thought.
But the biggest problem is in the analysis itself. The underground “plutonium waste” at Hanford is not all the same, and therefore it does not all threaten to enter the groundwater in the same way. Some of it may never contaminate the groundwater; some of it already has.
Though Alvarez initially acknowledges that “[t]he behavior of plutonium in the environment depends upon its chemical form,” and that plutonium chemistry is quite complicated, he quickly moves on from that good point and leaps into a dangerous assumption: that you can lump all the buried plutonium waste at Hanford into the same environmental threat category, if you will. It’s true that that reclassification and underestimation of waste types at Hanford give the appearance that more plutonium is buried than they originally thought, but surface contamination on a piece of equipment in a cardboard box is not going to travel the same way underground as, say, plutonium in the plumes of underground waste from leaking tanks. Equating types of plutonium contamination for the sake of saying that it’s all going to be an environmental hazard is a huge generalization, and a mistake.
Basically, Alvarez comes up with a very good idea: he raises the interesting question of how the DOE is classifying plutonium waste, how much is really out there, and how should federal agencies address it, but he makes quite a few assumptions. Everyone knows that Hanford is a mess, and everyone would like to know more about it, but his paper doesn’t accomplish that goal. It’s based on too many estimates and lacks the accuracy that would make it a solid piece of research.
What the Department of Energy Says
I received a statement via email from a contact at the Department of Energy regarding the New York Times article, and Alvarez’s paper. They made it clear to me that they consider the Alvarez paper as part of the public comment process on their Environmental Impact Statement (EIS) on Tank Waste Closure. They also emphasized that their final analysis will be based on actual data, versus estimates (emphasis mine):
The DOE Office of Environmental Management has asked an independent technical review board made up of scientists from the national labs, the Office of Science and NNSA to do a more comprehensive examination of Alvarez’s estimates. The board is reviewing the report now. This follows the normal protocol for completing an independent analysis of outside reports that are provided to the Department.
Many of Alvarez’s estimates are based on data we have collected as part of the EIS process. The Department’s estimates are based on our knowledge of the waste inventories and the processes used to generate them and include conservative bounds of what the contamination could be. But before we finalize any decisions on the cleanup, we undertake actual characterizations of the waste and base our final decision on that actual data.
During my recent visit to the Hanford Site, I got the impression that they are striving for transparency, which is why I’ll be very interested in what the outcome of their verification of Alvarez’s study will show.
As An Aside…
Finally, there are some statements that Alvarez makes that diverge, quite unexpectedly, from the topic of environmental concerns and plutonium waste. Curiously, he brings up accounting for fissile materials as part of arms reductions:
Characterization of radioactive wastes at nuclear weapons sites can reduce fissile material uncertainties necessary for deep nuclear arms reductions…
and, at the end of his paper, he talks about IAEA safeguards, which is confusing. Is Hanford plutonium waste something the IAEA should be interested in? It’s not exactly easy to make a weapon from it, so I’m not sure why Alvarez even brings this up:
The DOE’s Waste Acceptance Criteria system for WIPP appears to provide an adequate basis to allow for verification by the International Atomic Energy Agency. This would substantially increase the quantity of excess U.S. defense plutonium under IAEA safeguards, and demonstrate the U.S. commitment to irreversible nuclear arms reductions and set a precedent for international safeguards on other radioactive waste repositories containing significant quantities of plutonium.
I’ve given my input on the bulk of the paper, and some of the chemistry and environmental issues. I’d love to hear your thoughts on that, but I’m also interested in your thoughts on his ideas about DOE plutonium waste as something about which the IAEA should be concerned. What do you think?