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Category Archives: Radioactive Waste

Keeping Proper Track of Spent Fuel Pool Conditions

Lauren Gibson
Project Manager
Japan Lessons-Learned Directorate
 

While “spent fuel pool #4” at Fukushima Daiichi did keep its contents safe during the March 2011 accident, no one could confirm that during the accident. The plant’s staff and other experts, including the NRC, simply didn’t have enough information to know what was going on in the pool. Why not? There was no reliable way to measure the pool’s water level.

SFP_instrKnowing the water level is important because if the pool had boiled dry, it would have damaged the fuel and added to the accident’s radiation release. The Japanese plant’s staff did the right thing in assuming the worst and making many attempts to add water to the pool. They even dropped water from helicopters. If they had known the pools were OK, however, they would have been able to focus on addressing the real problem: the damaged reactors.

This experience led the NRC to order U.S. nuclear power plants to add instrumentation to their spent fuel pools. That way, if an accident occurs at a U.S. reactor, plant staff will be able to tell when the spent fuel pool needed attention. Spent fuel pool instrumentation will help plant staff properly prioritize their accident response and keep the public safe.

U.S. reactors already monitor a small fraction of the water level in the spent fuel pool. However, this system may not work if power is lost, as it was at Fukushima, and can’t provide advance warning of low water levels.

The NRC’s order requires U.S. reactors to be able to tell whether water is at or above certain important levels. The highest level means enough water is available for the normal cooling system to work. The second level marks the level of water needed to protect someone standing next to the pool from the fuel’s radiation. The lowest level is still enough to cover the fuel, but the plant staff should begin adding more water to the pool.

Of course, water may be added—and most likely would be—prior to reaching this point. The order also requires that plant staff must be able to read these levels from somewhere away from the pool, such as in the control room.

U.S. reactors must install the new instruments no later than two refueling cycles after they submit their plan to the NRC or by the end of 2016, whichever comes first. All U.S. plants submitted their instrumentation plans in February 2013. We’ve been reviewing the plans and we recently issued interim staff evaluations. These documents give the plants feedback so they can continue on the right track for implementing the order.

The evaluations also ask plants for additional information we need to complete our review. While the agency’s final approval is yet to come, the interim evaluations give plants the confidence to order equipment and move forward with installing the instruments. We’ll provide the plants a final staff evaluation when we can conclude that they’ll comply with the order by the deadline by following their plan. We’ll continue inspecting plants to confirm they’ve finished complying with the order.

Our website’s Japan Lessons Learned section has a page with more information about the order and related guidance.

We’re Waiting To Hear — Your Comments are Due on Waste Confidence

Keith McConnell
Director, Waste Confidence Directorate
 

The public comment period on the Waste Confidence proposed rule and generic environmental impact statement (GEIS) ends December 20. During the 98-day public comment period (the end date was extended due to the government shutdown), the NRC staff conducted 13 meetings around the country to receive your feedback.

wcd_banner_smallWe’d like to thank the more than 1,400 people who attended these meetings, either in person or by teleconference. We have posted transcripts of the public meetings on the Public Involvement section of our Waste Confidence webpage. We appreciate all of you who spoke at the meetings providing your thoughtful comments. The safe storage of spent nuclear fuel and the impact on the environment are critical issues in the country’s nuclear policy. We here at the NRC are committed to ensuring that spent fuel remains safely stored until a repository can be built for permanent disposal.

So what’s next? The staff of the Waste Confidence Directorate is busy cataloguing the tens of thousands of public comments we have received so far. You can read the comments we’ve processed already using ADAMS and http://www.regulations.gov/(search for Docket ID NRC-2012-0246). We are continuing to post comments, and of course we expect to receive additional comments up to the December 20 deadline. Instructions on how to submit comments are on the Public Involvement section of our Waste Confidence webpage.

Once the comments are fully catalogued, the staff will consider them and prepare responses to be included in the final GEIS and rule. These final versions will of course include any changes from the drafts stemming from the comments. We are working to issue the final rule and environmental study later in 2014.

Commission Sets Path Forward on Yucca Mountain

Dave McIntyre
Public Affairs Officer
 

The Commission today directed the NRC staff to finish the safety evaluation report (SER) for the Department of Energy’s Yucca Mountain construction authorization application. This direction is the agency’s response to the U.S. Court of Appeals for the District of Columbia Circuit, which in August ordered us to resume work on the application using approximately $11 million in unspent money from the Nuclear Waste Fund.

yucca 2The Commission reached this decision after obtaining views from numerous parties involved in the licensing process as to how it should proceed.

By way of background, Yucca Mountain is the proposed repository for spent nuclear fuel and high-level nuclear waste, a site selected by DOE at the direction of Congress. DOE submitted its license application in June 2008, but two years later withdrew it after the Obama administration decided not to pursue the project.

The NRC closed out its unfinished review of the Yucca Mountain application during Fiscal Year 2011. But a lot has happened since then, so it’s important to clarify what today’s action does and does not do.

The Order issued by the Commission today DOES:

• Direct the staff to complete and issue the SER left incomplete when the Yucca Mountain review was closed out;

• Direct the NRC Secretary and other agency staff to enter thousands of documents from the old Licensing Support Network (LSN) into the NRC’s ADAMS documents database so they will be available to the staff and eventually, assuming the availability of funding, to the public;

• Ask the Department of Energy to complete a supplement to its environmental impact statement on Yucca Mountain as the NRC staff found to be necessary back in 2008.

The Order DOES NOT:

• Direct the staff to reconstitute the LSN, which was dismantled in FY 2011;

• Restart the adjudicatory hearing on the application, which remains suspended;

• Signal that a licensing decision is imminent. Before a final licensing decision can be made, the adjudicatory hearing must be completed, and the Commission must perform its own review.

The Commission said it would consider the future of the LSN and the adjudicatory hearing once the tasks it directed today are completed and it can determine what tasks it can perform with whatever funds remain. The agency can only use money Congress has appropriated from the Nuclear Waste Fund for activities related to Yucca Mountain.

The SER is the key technical document of the NRC’s review of the Yucca Mountain application. It was to be published in five volumes: Volume 1, essentially the introduction, was published in August 2010. Subsequent volumes were not completed before the review was shut down – they were eventually published as “technical evaluation reports,” which are less formal documents that don’t contain regulatory conclusions about the proposed repository.

Although a finished SER would contain those conclusions, it will not be equivalent to a licensing decision, as discussed above.

Transporting Spent Nuclear Fuel: How Do We Know It’s Safe?

John Cook
Senior Transportation Safety Scientist
Division of Spent Fuel Storage and Transportation
 

In May, we talked about changes to NRC regulations regarding shipments of nuclear materials – including spent fuel. This month, we wanted to share the results of a periodic evaluation of the risk posed by spent fuel shipments. The NRC expects to publish the final study later this year. A draft was published in 2012.

Microsoft Word - diagram-typical-trans-cask-system-2.docSpent fuel shipments are strictly regulated and have not released any radioactive materials since they began more than 30 years ago. But the NRC still periodically evaluates the risks. As more data become available and computer modeling improves, these studies allow us to refine our understanding of these risks.

The latest study, Spent Fuel Transportation Risk Assessment, modeled the radiation doses people might receive if spent fuel is shipped between various sites. The study confirmed that NRC regulations for spent fuel transport are adequate to ensure safety of the public and the environment.

Both the NRC and the U.S. Department of Transportation oversee radioactive material transport. DOT regulates shippers, vehicle safety, routing, and emergency response. The NRC certifies shipping packages for the more hazardous radioactive materials, including spent fuel.

To be NRC-certified, a package must provide shielding, dissipate heat, and prevent a nuclear chain reaction. It must also prevent the loss of radioactive contents under both normal and accident conditions. The package must be able to survive a sequence of tests meant to envelope the forces in a severe accident. These tests include a 30-foot drop onto an “unyielding” surface (one that does not give, so the package absorbs all the force), a puncture test drop onto a steel peg, and then a 1475-degree Fahrenheit fire that engulfs the package for 30 minutes.

The 2013 risk assessment examined how three NRC-certified packages would behave during both normal shipments and accidents. It modeled a variety of transport routes using population data from the 2000 census, as updated in 2008. It used actual highway and rail accident statistics. It considered doses from normal shipments to people living along transportation routes, occupants of vehicles sharing the route, vehicle crew and other workers, and anyone present at a stop. And it used state-of-the-art computer models. The risk assessment found:

 Doses from routine transport would be less than 1/1000 the amount of radiation people receive from background sources each year

 There is less than a 1 in 1 billion chance that radioactive material would be released in an accident

 If an accident did release radioactive material, the dose to the most affected individual would not cause immediate harm

The 2013 risk assessment builds on earlier studies of transportation risks. It uses real-world data and equipment in place of generic designs and conservative assumptions. The first study, done in 1977, allowed the NRC to say that its transport regulations adequately protect public health and safety. Other studies done in in 1987 and 2000 found the risks were even smaller than the 1977 study predicted. These studies, together with analyses we perform on major transportation accidents, previous physical testing of package performance, and the global experience with thousands of completed spent fuel shipments, give the NRC confidence in the safety of spent fuel shipments.

For more information on how the NRC regulates spent fuel transportation, click here. To read our updated backgrounder on the subject, click here.

Let’s Chat about Waste Confidence

Andy Imboden
Chief of the Communications, Planning, and Rulemaking Branch
Waste Confidence Directorate
 

Update: My name is Keith McConnell and I am the Director of the Waste Confidence Directorate. Unfortunately, Andy Imboden, who was scheduled to moderate today’s Chat, can’t be here so I’ll be answering your questions.

I have been at the NRC since 1986, bringing my background and expertise as a geologist to various projects, including waste management, decommissioning and uranium recovery, as well as other positions. I have also served three NRC chairmen and in the Office of General Counsel.

I have a Bachelor’s degree in Geology from Clemson, a Master’s in Geological Sciences from Virginia Tech and a Ph.D. in Geological Sciences from the University of South Carolina.

Also, we’ve just posted a new YouTube Video – NRC Q&As Series: Three Minutes with Waste Confidence Directorate. Please give it a look.

 

On June 8, 2012, a U.S. Court of Appeals struck down the NRC’s Waste Confidence Rule. That rule contained the NRC’s determination that the environmental impacts of storing spent nuclear fuel after the end of a nuclear power plant’s license are not significant. The Waste Confidence ruling affected commercial nuclear power plant license reviews and spent-fuel storage reviews.

Picture2Tomorrow, from 2 to 3 p.m. EDT, I’ll respond to your questions during a Chat about NRC’s ongoing efforts to develop an updated Waste Confidence Rule. As you can imagine, many policy, legal, and technical issues will affect the rule.

By way of background, the Department of Energy is the federal agency with responsibility for the final disposal of the spent fuel in a deep geologic repository; the NRC’s role is to evaluate the application submitted to license the construction and operation of a repository. What the NRC is addressing currently (and in the Chat tomorrow) is how we’ll address the environmental impacts of the spent fuel after the nuclear power plant that generated it has stopped operating, but before it’s moved to permanent disposal elsewhere.

In the coming months, the NRC will release both a proposed new Waste Confidence rule and a draft generic environmental impact statement for public review and comment. But before we have that official comment period, I’m looking forward to answering your questions about proposed Waste Confidence Rule and the draft generic environmental impact statement. We want you to have as much chatdropquoteinformation as possible so you can fully participate in the official comment process.

Prior to our Chat, you can visit NRC’s Waste Confidence website for more information.

If you have any questions before tomorrow’s Chat, you can submit them to OPA.Resource@nrc.gov. I’m looking forward to your questions and comments. Just one note, though, this Chat is informal and your comments will not be included in our official comment process.

I look forward to hearing from you on July 23d.

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