U.S. NRC Blog

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Monthly Archives: July 2013

Astounding Facts about the NRC and Radioactive Materials: Part II

Brenda Akstulewicz
Regulatory Information Conference Assistant

As promised, here are some more interesting bits of information about the NRC and nuclear history and science.

washingmachine• The indicator lights in early appliances ─ such as clothes washers and dryers, coffeemakers, and stereos ─ used Krypton–85, a radioactive isotope.

• The Office of Federal and State Materials and Environmental Management Programs consults with 31 federally recognized Native American tribes on proposed new uranium recovery projects in Wyoming, South Dakota and Nebraska.

• The NRC performs classified reviews of new Naval Reactor submarine and aircraft carrier reactor plants and provides advice to the Navy on the designs. This practice was initiated by President Kennedy in the 1960s.female

• Three women, including the current chairman, Allison Macfarlane have held the title of Chairman, Nuclear Regulatory Commission. The other two are Shirley Jackson and Greta Dicus.

• From 2007 to 2012, NRC received 68 petitions for rulemaking. Of those, 21 were denied and 17 were either fully considered or partially considered in the rulemaking process. The remaining 30 are under staff review.

• In the past five years, the Office of Nuclear Regulatory Research has issued 244 new or revised regulatory guides, withdrawn 43 guides, and determined another 48 guides to be acceptable as written.

• Glenn T. Seaborg, the scientist who discovered plutonium, was also a chairman of the Atomic Energy Commission – the predecessor of the NRC.

florida• In 1992 Hurricane Andrew struck the Turkey Point nuclear power plant in Southern Florida, which prompted the NRC and FEMA to enter into a “Memorandum of Understanding” regarding emergency preparedness.

• NRC’s longest serving commissioner was Commissioner Edward McGaffigan. He served 11 years (from1996-2007) after appointments twice by President Clinton and once by President Bush. He died while still serving on the Commission.

• There are 438 nuclear power reactors operating worldwide.

exitsigns• Tritium gas is used to illuminate exit signs in buildings so they will function without power. Promethium-147 and Krypton-85 are approved by the NRC for use in exits signs.

• On average, NRC expends 6,160 hours of inspection effort at each operating reactor site each year.

Keeping Fort Calhoun’s Tornado Analysis Up To Date

Scott Burnell
Public Affairs Officer

When someone mentions the Fort Calhoun plant in Nebraska, flooding issues are probably what comes to mind these days. But the tornadoplant has to withstand everything that Mother Nature can throw at it and tornadoes, obviously, are in the mix.

Fort Calhoun’s been doing some work recently that has the plant operator asking the NRC for permission to revise how its license specifies how to determine tornado effects. Fort Calhoun’s request fits into its ongoing efforts to resolve the issues that have kept the plant shut down since early 2011. The plant, about 19 miles north of Omaha, Neb., has already reinforced several areas of the site against potential tornado damage based on analysis with an NRC-approved method.

That method uses more realistic criteria related to the impact of flying debris in a tornado. While that tornado analysis method is approved, Fort Calhoun’s license still reflects older information, so the plant needs to formally bring the license into line with the analysis method’s criteria.

Fort Calhoun’s owner, the Omaha Public Power District, believes their proposed license change won’t affect the plant’s overall risk of an accident, and the company’s asked the NRC to review the request using a faster process. If we agree a quicker review is appropriate, we could come to a decision on the license change within a couple of days and then offer an opportunity for a public hearing after the change.

More information on Fort Calhoun’s request is available on the NRC’s website, and we have a notice in the local paper as well. Our public meeting in Omaha tonight will discuss our inspection activities and the overall progress Fort Calhoun has made in addressing agency concerns, as well as this most recent request.

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.

Fort Calhoun: Progress but Scrutiny Continues

Lara Uselding
Public Affairs Officer, Region IV

Here are some of the latest statistics related to the ongoing shutdown of the Ft. Calhoun nuclear power plant in Nebraska:

• 27 months being shutdown

• Seven separate NRC team inspections on site in 2013

• About 40 NRC inspectors on site this year

• 15 restart checklist items left to be evaluated and resolved by the plant owner before restart

fcsWhat does this add up to? A nuclear power plant still being scrutinized by the NRC since a 2011 refueling outage followed by record Missouri river floods, a breaker fire and additional restart complications.

Yesterday, the NRC issued the results of a restart readiness inspection at the plant, which is, operated by the Omaha Public Power District (OPPD). The inspection report is a lengthy document detailing 36 findings by NRC inspectors.

A majority of the findings have to do with the plant operator not thoroughly or consistently evaluating and resolving problems within the Corrective Action program. Some of the other findings deal with not following procedures as outlined by plant documents known as technical specifications.

Based on the results of the inspections, the NRC has concluded that five areas on the Confirmatory Action Letter Restart Checklist were adequately addressed by the licensee and will be closed. That means that NRC believes OPPD has appropriately addressed third-party safety culture assessment, quality assurance, integrated organizational effectiveness, human performance, and their review of licensing commitments. A second report issued last week also closes out the area of emergency preparedness.

This means plant’s officials have made improvements in areas that led to their performance decline. For example, OPPD completed a third-party safety culture assessment that gave them a better understanding of human performance, problem identification and resolution, and decision-making deficiencies that led to their performance decline. They have implemented short term actions and are developing long-term action plans to address future performance improvements.

In addition, the NRC has determined that OPPD has successfully addressed the area of organizational effectiveness that translates to improvements in management oversight of facility activities.

NRC has announced the next public meeting will be held in Omaha on July 24. At this meeting, we will present a status of our inspection activities and OPPD will provide an update on their actions.

The NRC will later conduct follow-up inspections to look at the remaining open performance areas and to see if plant personnel, equipment, and processes are ready to support the safe restart.

Where There’s Steam, There’s … a Steam Generator

Kenneth Karwoski
Senior Advisor for Steam Generators

News articles recently brought the phrase “steam generators” into the national conversation, but we’re not talking about teakettles. pwr[1]Steam generators provide vital technical and safety functions at many U.S. nuclear power plants.

In the United States, steam generators are only found in 65 pressurized-water reactors, one of the two types of U.S. reactors. There can be two to four steam generators for each reactor unit. The generators mark the spot where two closed loops of piping meet. The first loop sends water past the reactor core to carry away heat, and this loop is at such high pressure that the water never boils. The second loop is at a lower pressure, so the water in this loop turns to steam and runs the plant’s turbine to generate electricity.

The steam generator’s main technical job is to let the first loop pass its heat to the second loop as easily as possible. To do this, a steam generator packs thousands of small tubes closely together, allowing the maximum area for heat to pass through the tubes and into the second loop’s water.

At the same time, the steam generators provide an important safety barrier – the first loop can contain radioactive material, so the tubes must keep the two loops of water separate. NRC rules require plants to closely monitor the second loop and immediately shut the reactor down if a tube leak exceeds very strict limits.

The NRC’s rules for inspections, maintenance and repair of steam generator tubes help ensure the tubes continue providing the safety barrier. If an inspection shows a tube is starting to get too thin, the plant will repair or even plug a tube to maintain safety.

Steam generator tube material has improved over time. The first steam generators had tubes made from a type of stainless steel that experience showed could be corroded by the chemicals, temperatures and pressures in the first and second loop. Over time, plants have replaced those steam generators with ones using more advanced alloys that are less likely to corrode. Steam generator replacement only happens when the reactor is shut down for refueling, and plant owners bring in hundreds of specialized workers to safely remove the old generators and install the new ones. The old generators have to be safely disposed of as low-level radioactive waste.

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