Friday, March 15, 2019

What’s in a name: Defining the problem with nuclear waste

Two developments in recent weeks herald potential major changes in the long-term federal effort to clean up the highly contaminated Hanford nuclear reservation in southeast Washington. The result, if we’re not vigilant, could be significant degradation in the quality and long-term effectiveness of that cleanup.
  • A new report greatly increased both the estimated cost and the time it will take to finish the Hanford cleanup.
  • The U.S. Department of Energy wants to redefine what constitutes high-level nuclear waste.

Multiple images pieced together showing panoramic view of Hanford waste tank interior.
A panoramic view, assembled from multiple photos, inside Hanford tank AX-104.
What’s at stake? Whether millions of gallons of toxic, radioactive waste are effectively removed from the environment, or whether that waste will be left to eventually make its way into the groundwater and from there into the Columbia River.

Even before the cost and timeline report came out at the end of January, pressure was building for the federal government to reduce Hanford clean-up costs. This proposal would accomplish that by backing off the federal government’s decades-old legal and moral commitment to a clean-up that truly protects public health and the environment from waste that makes the site one of the most contaminated places on Earth.

Origin vs. characteristics

One of the chief arguments in favor of the federal Energy department’s move to redefine high-level nuclear waste is that the definition is based on where the waste originated, rather than on its level of radioactivity. It only makes sense, the argument goes, to define waste based on its physical characteristics rather than where it came from.

If that were to happen, proponents say, only about 10 percent of Hanford’s tank waste would qualify as high-level. The rest could be treated much more quickly and cheaply as low-level.

While that has a certain logical appeal, it misses the point. Here’s why: Regulators and the federal Energy department agreed years ago to treat 90 percent of Hanford’s tank waste as if it were low-level, provided that the waste is vitrified (incorporated into glass). That is the status quo.

The crux: how to treat the waste

So what’s the question? The real issue here is how that low-activity waste will be treated and disposed of.

Currently, Energy has agreed to incorporate much of the waste into glass, encase it in steel canisters and place it in engineered landfills on the Hanford site. Glass should hold the waste stable and keep it from re-entering the environment. Especially, it should keep it out of the water table and the Columbia.

If Energy is allowed to redefine waste, it could unilaterally – without oversight from the Nuclear Regulatory Commission, the Environmental Protection Agency or our own Department of Ecology – determine how to treat and dispose of the 90 percent it would likely declare to be low-level.

Since it already plans, with our concurrence, to treat 90 percent as if it were low-level, we conclude that there’s really only one reason to proceed with a new definition. And that is to back away from its commitments to retrieve as much waste as possible from Hanford’s 177 underground tanks and incorporate much of it in glass. 

Leave it in the tanks?

Instead, Energy could propose to leave millions of gallons of waste in the tanks and simply dump concrete on top of it. Or it could propose to retrieve the waste and essentially do the same thing – incorporate it into concrete and dispose of it at Hanford or elsewhere.

The problem: concrete is porous and relatively short-lived. It might keep the waste out of the water table for a few years, or even a few decades, but eventually waste mixed with concrete will seep out, back into the environment. Our environment.

As for cost and timeline, we agree that the new projections are troubling. The federal government already has spent billions designing and building plants intended to glassify Hanford’s tank waste. The low-activity waste plant is on schedule to begin operation in just a few years. 

A promise made

However, the total cost of Hanford cleanup – even at the new projected levels – is a small fraction of the total the nation has spent on nuclear defense. We in Washington State and our neighbors along the Columbia River in Oregon have done our part. We expect the federal government to stick to its promises to properly, effectively clean up the mess it made.

Furthermore – the costs and timelines are based on current levels of funding. We’ve been pointing out for years that if spending was increased now to the levels required to meet current commitments, the longterm total cost and the time to complete the cleanup both would be significantly reduced.

For these reasons, we remain opposed to the federal Energy department’s proposal to give itself unilateral authority to redefine high-level nuclear waste.

1940s-era nuclear reactor with smokestack, surrounded by shrubbs and hills.
Hanford's B Reactor - the world's first nuclear reactor.

Hanford: The cradle of nuclear waste 

Nuclear waste, like all things nuclear, began at Hanford. 

Hanford’s B Reactor was the world’s first large-scale nuclear reactor. And as soon as it began operation, it began to create radioactive waste. In a commercial reactor, once the uranium fuel rods no longer yield enough heat to generate power, they are removed and that’s essentially the end of the process. But in the production of weapons-grade plutonium, those rods are treated with toxic chemicals to separate the small quantities of plutonium created by the reaction.

The plutonium was collected, refined and made into nuclear weapons. The radioactive, toxic stew that created in the process was stored in Hanford’s underground tanks.

Although the definition of high-level nuclear waste evolved in the early days, it has for decades been defined as the spent fuel rods and associated materials created in nuclear reactors. Energy’s current proposal would base the definition on the level of radioactivity – and would give Energy sole authority to make that determination.

Earthen berm covering Hanford PUREX Tunnel 1 showing hole where part of roof collapsed.
PUREX Tunnel 1 showing the hole where part of its roof collapsed in 2017.

What about PUREX?

In 2017 and again in 2018, we approved Energy projects to stabilize the two PUREX tunnels with concrete.

So if concrete was good enough for PUREX, why not for tank waste?

The answer: Because these are two very different applications. While the material in the two PUREX tunnels is highly radioactive, it is almost all equipment. There is little, if any, liquid. Also, a portion of PUREX Tunnel 1’s roof collapsed and the consensus was that Tunnel 2 was vulnerable to collapse.

Concrete fills the tunnels so they can’t collapse, and stabilizes the contents.

Waste in the tanks, on the other hand, contains a high percentage of liquid. If a tank is filled with concrete, the liquid will eventually seep out of the concrete, out of the corroding tank and into the ground.

- Randy Bradbury, communications manager, Nuclear Waste Program

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