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Browns Ferry: A New Milestone in Nuclear Plant Fire Protection

Barry Miller
Senior Project Manager, Fire Protection Branch

The NRC recently marked a milestone with the transition of the Browns Ferry nuclear power plant to the National Fire Protection Association’s Standard 805 (NFPA 805). The license amendment, issued October 28, is significant because it marks 23 reactors at 15 plants to have completed the transition since 2010. It is symbolically important because a fire at Browns Ferry in March of 1975 prompted the NRC and the industry to focus on fire safety at nuclear power plants.

Fire Protection infographic_r13The Browns Ferry fire started when a worker used a candle to test airflow around a temporary penetration seal in the cable spreading room. The flame ignited the temporary seal material, and the fire spread to the reactor building where it burned many of the cables in systems required to safely shut down the plant.

Although plant operators were able to shut the plant down safely, the event led the NRC to promulgate prescriptive fire safety requirements (10 CFR Part 50, Appendix R). For example, plants were to ensure there was at least 20 feet of separation between trains of redundant safety systems. However, this requirement was impractical for some plants that had already been built, so in many cases licensees had to find an alternative means of achieving an equivalent level of safety.

“The fire at Browns Ferry in 1975 was a turning point for the nuclear industry,” said Bill Dean, director of the Office of Nuclear Reactor Regulation. “It put a spotlight on the risk fires can pose to nuclear safety. Many safety improvements have been made industry-wide since that time, but the adoption of NFPA 805 represents perhaps the most significant undertaking in fire safety since the institution of Appendix R. This transition means Browns Ferry has performed a full re-analysis of the fire risk at its three reactors and identified the most efficient and effective means to protect its most fire-sensitive areas.”

The NFPA 805 is a performance-based means of using advanced fire analysis tools to assess the risk of fire at various areas of a nuclear power plant. That way, a plant’s fire protection scheme can be customized to focus on the most risk-significant areas and to protect the reactor’s safety systems.

Using the NFPA 805 standard is optional. Newer plants constructed after 1975 were typically built to the prescriptive requirements. So they may opt to remain under those requirements, contained in 10 CFR 50.48 and still be in compliance with the agency’s fire protection regulations. Although NFPA 805 offers certain advantages from a risk-informed perspective, both methods provide reasonable assurance that a plant would be able to cope with a serious fire.

The following plants have now completed the transition to the NFPA 805 fire protection standard: Shearon Harris; Oconee 1, 2 & 3; D.C. Cook 1&2; Duane Arnold; Callaway; Fort Calhoun; V.C. Summer; Cooper; Nine Mile Point 1; Turkey Point 3 & 4; Farley 1 & 2; Brunswick 1 & 2; Palisades; Arkansas Nuclear One Unit 2; and Browns Ferry 1, 2 & 3.

Preparing for Subsequent License Renewal

Albert Wong
Division of License Renewal
Office of Nuclear Reactor Regulation

The NRC’s operating licenses for commercial nuclear power reactors are valid for 40 years and may be renewed for an additional 20 years at a time.  So far the agency has renewed 78 licenses and has applications for another 16 under review. We received the first license renewal application in April 1998, and we’re expecting to receive the last application for a first renewal sometime after 2020.

Today, Dominion Virginia Power announced that it expects to submit a subsequent license renewal application in 2019 – a renewal beyond the 60 years of operation from the first license and the initial renewal — for Surry Power Station.

Subsequent renewal applications will be reviewed under the same regulations (10 CFR Part 54) as the initial renewals. That means they will get similar scrutiny for both safety (focusing on how the plant operators manage the effects of aging on certain plant components) and environmental impacts. There will also be opportunities for public input and hearings.

Of course, operating plants beyond 60 years may raise different technical issues for us to address in these reviews. So we are drawing on our experience with the initial license renewals, plant operating experience, ongoing research, and expert opinions to identify strategies for dealing with the challenges of extending operation to 80 years. Two draft guidance documents will be published in December 2015 for public comment. They are “Generic Aging Lessons Learned for Subsequent License Renewal Report” and the “Standard Review Plan for Review of Subsequent License Renewal Applications for Nuclear Power Plants.”

The final guidance documents – including responses to public comments and explanations of any changes from the drafts – will be published in time to support our review of subsequent license renewal application.

Plant operators applying for subsequent license renewal will need a detailed technical basis, along with associated research and “aging management programs,” to demonstrate how they will keep their plants operating safely during the additional 20 years. The NRC staff will give these applications the same thorough reviews we give initial renewals. We expect the reviews will take about two years, though the quality of the applications could affect the schedule.

The NRC is proactively preparing for anticipated subsequent license renewal applications and stands ready to ensure the continued safety of operating plants once applications are received.



FitzPatrick Nuclear Power Plant to Halt Production in 2016 or 2017

Neil Sheehan
Public Affairs Officer
Region I

The James A. FitzPatrick nuclear power plant has become the latest U.S. commercial power reactor to announce plans to cease operations by the end of the decade. Situated on Lake Ontario, the Scriba (Oswego County), N.Y., facility will permanently shut down either in late 2016 or early 2017, its owner, Entergy, said Monday.

fitzAs was the case with other plants that have previously disclosed shutdown plans, poor economics fostered by an abundance of low-cost natural gas was cited by the plant owner as a primary driver in the decision-making.

The NRC does not have a role in decisions made by plant owners on continued operations based on economics and other factors.

FitzPatrick, a roughly 840-megawatt boiling water reactor that came online in July 1975, joins these plants that will be closing in coming years: Pilgrim, in Plymouth, Mass., by June 1, 2019, and Oyster Creek, in Lacey Township, N.J., by Dec. 31, 2019.

The Vermont Yankee nuclear power plant, in Vernon, Vt., generated electricity for the last time in December of 2014. Entergy also owns Pilgrim and Vermont Yankee while Exelon owns Oyster Creek.

By contrast, an operating license was just granted last month to Watts Bar 2.

The NRC will continue to provide rigorous regulatory oversight of the FitzPatric facility. Our inspections will be focused on ensuring plant safety and security for the remainder of its operational life.

That oversight will include the ongoing presence of two NRC Resident Inspectors based at FitzPatrick on a full-time basis until the reactor is removed from service.

More information regarding the agency’s nuclear power plant oversight activities can be found on the NRC’s website.

Counting the Costs on Advanced Reactor Reviews

Anna Bradford, Chief
Advanced Reactors and Policy Branch
Office of New Reactors

We’re continuing to examine topics from the recent two-day public workshop we jointly hosted with the Department of Energy regarding non-light water reactor designs. One topic getting a lot of attention is the possible costs for NRC reviews of applications for these designs.

Last month’s workshop included presentations on the NRC’s experience licensing non-light water designs, as well as discussions of proposed advanced reactor designs.

Last month’s workshop included presentations on the NRC’s experience licensing non-light water designs, as well as discussions of proposed advanced reactor designs.

For instance, some people interpreted a DOE presentation on the Next Generation Nuclear Plant project as saying it costs $800 million to receive a final certification or license from the NRC. The bulk of that $800 million, however, falls outside of NRC fees and would be made up of the designer’s costs to develop and test its design to ensure that it works as planned.

In other words, the designer does not pay the NRC $800 million to review a reactor design. Looking at recent reviews of large light-water reactors, we see designers spent approximately $50 – $75 million for NRC fees to certify their designs.

A recent Government Accountability Office assessment, “Nuclear Reactors: Status and Challenges in Development and Deployment of New Commercial Concepts” says costs can be “…up to $1 billion to $2 billion, to design and certify or license the reactor design.” A different portion of the GAO report, however, pointed out most of these costs aren’t attributable to the NRC review. The largest part of the price tag would be research, development, and design work to develop and test a new reactor design.

We can also examine information from the public workshop on design development costs versus NRC review costs for the developer of a new small modular reactor design. The company said that of approximately $300 million in design investment to date, only $4 million of that amount (or slightly more than 1 percent) is from NRC fees for several years of pre-application interactions with the agency.

Here’s something to keep in mind: NRC review costs depend on the quality and maturity of the applicant’s information. The NRC always aims to efficiently and effectively review designs. Incomplete or inadequate information will very likely increase costs, however, since the NRC will spend more time and effort getting the data necessary to determine whether the reactor could operate safely and securely.

Everyone benefits from a common understanding of NRC costs as we discuss the next generation of reactor designs. The NRC’s website has more information on how the agency is approaching advanced and small modular reactor designs.

Defining the Color of Oversight

Lara Uselding
Public Affairs Officer
Region IV

We regularly interact with various audiences from the media to the public and one question pops up often: Why does the NRC use colors to discuss issues found at a plant and what does it all mean?

PI_ROPThe quick answer is that color-coding is a lot more understandable to people outside the agency than trying to interpret a probabilistic risk calculation of core damage frequency of 10-5. (The NRC uses probabilistic risk in assessing the potential safety significance of nuclear safety issues and plant performance indicators so inspections focus on those plant activities that could have the greatest impact on safety.)

The colors we use — green, white, yellow and red — are used to prioritize the findings with greater safety significance. A more risk-significant issue is called a red finding and that will move an operating plant into our highest category for oversight followed by thousands of extra hours of inspection. An example would be a failure in a key safety-related component.

A green finding might be given when an inspector finds that one of 10 bolts on a valve is looser than the others and should be tightened. While it may not sound like a big deal, the NRC has high standards for safety and a low threshold for issues.

White and yellow findings are medium risk. In 2015, 428 green findings, 13 white findings and two yellow findings were issued. An example of a yellow finding was one given for seals that were not adequate to protect a room housing electrical equipment from flooding. An example of a white finding was for improper maintenance that resulted in a failed emergency diesel generator fan belt.

Who decides the colors? Initially, the inspector determines the safety significance and assigns a tentative color. A green finding may not require additional analysis. But with the higher colors, there is a detailed assessment that could involve NRC risk experts and, in some cases, a discussion with the plant operator to obtain more information.

The final outcome of the review — evaluating whether the finding is green, white, yellow, or red — will be used to determine what further NRC action may be called for, such as moving a plant up in the columns that comprise the NRC’s performance “Action Matrix.” When poor performance lands a plant in one of these higher oversight columns with increased inspections, it takes a lot of hard work to return the plant to a better standing.


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