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Monthly Archives: February 2013

Deconstructing the Decommissioning Process

Dave McIntyre
Public Affairs Officer
 

Duke Energy’s decision to shut down the Crystal River 3 reactor in Florida rather than pay for expensive repairs to its containment dome has focused attention once more on the lengthy process for decommissioning nuclear power plants. Since Dominion Nuclear’s announcement last year that it will shutter its Kewaunee plant in Wisconsin, the country now has two reactors entering this process.

crDuke took the first step on Feb. 20, when it gave the NRC its official certification that it had permanently ceased operations at Crystal River 3 and permanently removed the fuel from the reactor. Those certifications effectively changed the plant’s operating license to a “possession only” license – in other words, the company is no longer permitted to load fuel into the reactor vessel and operate the plant.

After these initial certifications, the process can be quite slow. Duke will have up to two years to develop and submit its decommissioning plan – officially called the post-shutdown decommissioning activities report, or PSDAR in NRC-speak. The report will include a description and schedule for decommissioning activities, their estimated cost, and a discussion of why any anticipated environmental impacts have already been reviewed in previous environmental reports on the plant.

Once the NRC receives the PSDAR, we will publish it for public comment and conduct a public meeting near Crystal River to explain the decommissioning process. Duke will not be able to conduct any major decommissioning activities until 90 days after NRC receives the PSDAR.

Under NRC regulations, Duke can take up to 60 years to complete the process, from cessation of operations to final decommissioning and termination of license. Why so long? There are actually two advantages: Radioactivity decays over time, making the final cleanup easier; and the company’s decommissioning trust fund continues to grow. This stage of decommissioning is called SAFSTOR, as the company maintains the shuttered plant in safe storage until final cleanup begins.

Throughout this process, Duke will be able to use some of its decommissioning funds. It can spend up to 3 percent of the fund on decommissioning planning as it develops the PSDAR, and up to 20 percent to maintain and monitor plant safety during the SAFSTOR period. NRC limits use of the funds to ensure that enough money remains to complete cleanup and follow the process through to license termination.

The NRC requires Duke to clean up the site so that residual radiation is quite low – specifically, that no person on the site would receive a dose above 25 millirem per year. (In comparison, the average American receives 310 millirem per year from natural radiation, and the dose from a single chest X-ray is about 10 millirem.) At least two years before Duke reaches that point, it must submit a license termination plan, detailing the final steps. NRC inspectors will verify that the site has been decontaminated to the NRC’s requirements. Duke will then ask the NRC to terminate the license, or modify it to apply only to a spent fuel storage facility, if needed.

One popular question is the cost of decommissioning a nuclear power plant. Estimates vary, and of course it has been several years since a plant has been decommissioned, but the NRC estimates that the costs generally range from $300-400 million. This estimate applies only to NRC-mandated activities – in other words, reaching the radiological criteria. Dismantling other parts of the plant (such as support buildings) would cost extra, so the company’s estimate might be higher.

Throughout the entire decommissioning process, the NRC’s objective is to protect public health and safety while ensuring that the site is cleaned up to our requirements.

For more information, NRC regulations on decommissioning are 10 CFR 50.82 and 10 CFR 20, Subpart E.

Additional Note: There are two other possible methods for decommissioning. DECON involves active decontamination of the site, either immediately after operations cease or after a period of SAFSTOR. The third, ENTOMB, is just what it sounds like – radioactive contaminants are permanently encased on site in structurally sound material such as concrete and appropriately maintained and monitored until the radioactivity decays to a level permitting restricted release of the property. To date, no NRC-licensed facilities have requested the ENTOMB option.

Celebrating African American History Month: NRC Applauds Achievement of Dr. Haile K. Lindsay

Note: Dr. Lindsay was honored this month with a Special Recognition Award at the 2013 Black Engineer of the Year Science, Technology, Engineering, and Mathematics (STEM) Conference. Lindsay holds a B.S., M.S., and Ph.D. in mechanical engineering from North Carolina A&T State University.

Haile K. Lindsay
Thermal Engineer
 

After receiving my award, I was asked to write a bit about what I do at the NRC and how I contribute to the African American community – thus this post.

Haile-Work-Picture-March2008I will have been with the agency for five years. I came to the NRC right after getting my PhD. My job is to review the thermal and containment sections of the license applications we receive for packages to either store or transport spent fuel or radioactive materials. My job allows me to apply the knowledge I acquired in school about heat transfer, thermodynamics, and other critical subjects. I review the package designs to see if they meet NRC regulations for safety and security of people and the environment. If a design does not meet our requirements, we will not issue a license.

The mantra I live by is: “Hard Work Pays Off.” If you work hard, you can be successful at anything you do. I saw that come true as a student, and now in my career at the NRC. My dissertation focused on treating liposarcoma (a rare tumor that develops in fat cells, typically in extremities) using hyperthermia – that is, heating cancer cells enough to destroy them. I am proud that my research contributed to the body of knowledge on this relatively new mode of cancer treatment.

At work, I was honored to learn that my branch chief at the time, Victor Cusumano, had nominated me for this prestigious award. I credit my hard work toward becoming a qualified thermal reviewer, ensuring that corporate knowledge is transferred to the newer NRC employees, as well as papers I have presented at nuclear and government conferences and the work I have done to organize NRC conferences.

I also work hard to give back to my community. In my role as NRC Chapter President for Blacks in Government, last year I organized a clothing and toiletries drive entitled Winter H.O.P.E. (Helping Others by Providing Them Essentials). The clothing and toiletries, donated by the NRC staff, were given to The Dwelling Place – an organization that provides housing opportunities and support services in Montgomery County, Md., for families experiencing homelessness. I also organized a luncheon last summer for 17 D.C. Summer Youth Employment Program interns who worked at the NRC. We provided pizza and organized a panel to talk with these young people about our respective career paths and provide some helpful tips for success.

I feel truly honored and blessed to have been recognized with such a prestigious award. This award will fuel me to continuously do even greater work for this agency and my community.

Thermal Hydraulics: Heat, Water, Nuclear Power and Safety

Scott Krepel
Reactor System Engineer
 

One of the most important safety questions in a nuclear power plant is: Can you cool the very hot nuclear fuel in an accident when normal cooling is disrupted? The scientific field best equipped to answer this question is called “thermal hydraulics.”

bwrThe first part of the term, “thermal,” relates to heat transfer, such as the movement of heat from the burner on a stove to the water in a pot via the metal of the pot. The second part, “hydraulic,” relates to the flow of a fluid such as water. The combination, “thermal hydraulics,” can be applied to systems where both the flow of fluid and the transfer of heat are important – such as a nuclear power plant.

I work in the NRC’s Office of Nuclear Regulatory Research as part of a team dedicated to expanding our understanding of thermal hydraulics and applying that understanding in nuclear power plant safety. Over time, we’ve put much effort into incorporating existing knowledge into the NRC’s thermal hydraulics computer simulation program, TRACE. This program allows NRC staff to construct computer models of the cooling systems of a nuclear power plant and then simulate accidents such as pipe breaks (but not wildly improbable events such as the considerable destruction caused near the end of a typical superhero action movie).

TRACE is constantly being pushed to become more accurate, reliable and versatile. Universities and test facilities around the world are conducting experiments and accident simulations to collect real-world data that can be used to determine TRACE’s ability to accurately predict specific phenomena. We use the outcomes to update the program as needed to make it more accurate and to better capture certain phenomena.

Sometimes, new safety issues may result in further investigation of certain scenarios and further evolution of TRACE. Ultimately, the goal of this work within the research arm of the NRC is to continuously expand our understanding of situations which may impact the cooling of the nuclear fuel. This knowledge can then be used to ensure that the public and the environment are protected in the unlikely event of an accident at an U.S. nuclear power plant.

How the NRC is Responding to the Cooling Water Leak At the Palisades Nuclear Plant

Prema Chandrathil
Region III Public Affairs Officer
 

On Friday, the Palisades plant in Covert, Mich., shut down so plant personnel could find and repair a leak somewhere in the reactor’s cooling water system. Soon after, the NRC dispatched an additional inspector from the Regional III office, located in Lisle, Ill., with a background in mechanical testing and repairs. He supplements the two NRC resident inspectors as they evaluate the plant’s repair activities.

palisades_smallFor more than a week now, the NRC resident inspectors on site have been following the actions taken by workers at Palisades to find the leak. The resident inspectors reviewed the data. They also watched plant workers as they isolated different parts of the system to conduct tests to try and identify exactly where the leak was coming from.

Plant workers caught the problem because the water level in the component cooling water system was going down slowly. This system uses non-reactor water to cool certain safety equipment. Per NRC regulations the system is required to be monitored. When the plant shut down the system was leaking about 35 gallons per hour. This water was captured and released to Lake Michigan through an established monitored release path. The leak did not place the plant or the public in danger.

It’s now believed a heat exchanger in the system is the source of the leak. A heat exchanger is basically a box that contains around 2,000 tubes. The tubes have water running through them to remove heat from equipment, such as seals or pumps. This heat exchanger plays an important role to cool necessary equipment during normal operation, but also during potential accident scenarios.

Palisades has two safety-related heat exchangers in this particular system; both are required by NRC regulations to be in working condition and ready to respond at a moment’s notice. With one of the two exchangers potentially not working right the plant decided to shut down before the regulations required it. NRC regulations state if there is a problem with the heat exchanger it would need to be fixed within 72 hours. If that’s not possible the regulations require the plant to shut down to find the leak and make the appropriate repairs. The plant will only be able to restart when the heat exchanger is working correctly.

Over the weekend all three NRC inspectors continued to monitor and assess the repair work to find and fix the leak. The NRC will continue to closely follow this event and observe how the plant goes about these activities with safety in mind from start to finish. We know the community is interested and concerned about these types of issues and continue to work to keep our commitment to ensure they are informed.

One of our initiatives is to provide summaries of conversations between the NRC and plant staff to the public. A summary of such a conversation about this leak, which took place on Thursday, Feb.14, will be available to the public in the near future. Our assessment of this issue will also be documented in a publically available inspection report.

The Online Public Meeting Schedule – A Resource for the Interested Public

Adam Glazer
Librarian, Public Document Room
 

calendar

The NRC hosts hundreds of meetings throughout the year. Many of the meetings are held so you, the public, can share your thoughts about nuclear power issues. While the meeting topics vary, the way to find out about them doesn’t — you check the Public Meeting Schedule on the NRC’s Web site.

You’ll find the date and time, purpose and agenda, location, and contact name and phone number. When you click on the link to the agenda, you’ll be able to find out more information, such as who from the NRC is planning on attending the meeting. If there’s a telephone icon, there will be a phone number so you can listen in on the meeting remotely instead of traveling to it.

Our goal is to give you at least 10 days advance notice before a meeting, so that you can arrange your schedule to participate if it’s a topic you’re interested in. A word of caution – please keep checking the Web site in case there’s been a change to the meeting. Also, if there’s bad weather, we may have to cancel or postpone the meeting.

In 2012, we posted information about 1,147 meetings. There are sure to be many meetings in 2013. Perhaps one will interest you?

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