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NRC Talks Research in Tennessee

Salman Haq
Reactor Engineer
Office of Nuclear Regulatory Research

We recently issued the draft report summarizing detailed research and analyses into what might happen during an accident at a nuclear power plant. Tomorrow, we’ll head to the third plant we analyzed, Sequoyah Nuclear Plant, to discuss the results with the surrounding communities. The plant is located in Soddy-Daisy, Tenn.

Cover of SOARCA Communications Brochure (NUREG BR-0359 Rev2)The project, called the State-of-the-Art Reactor Consequence Analyses, or SOARCA, looked at potential situations that could disable a reactor’s normal safety systems. The project used powerful computer programs to predict the plants’ behavior based on decades of real-world experiments into issues such as how reactor fuel responds during the extreme temperatures expected during these accidents.

SOARCA then plugged up-to-date information about the plants into the programs and examined how a potential accident might unfold.

We found that safety equipment the NRC required after the 9/11 attacks, or additional equipment that industry voluntarily added following the Fukushima event, if used according to plan, would help prevent or mitigate a reactor accident. Even for the most severe accidents the research came to three basic conclusions:

  • Accidents occur more slowly than we originally thought;
  • Accidents release less radioactive material than we originally thought; and
  • The emergency plans every U.S. reactor has in place can help keep people safe.

The project came to some more specific conclusions about accident effects around the three plants, Surry (southeast of Richmond, Va.), Peach Bottom (southeast of Lancaster, Pa.), and Sequoyah. For example, the slowly developing nature of the accidents and the existing emergency plans would help keep people safe, even during uncontrolled accidents.

Some of the NRC staff involved in SOARCA discussed the Sequoyah project on April 20, at the TVA Sequoyah Nuclear Training Building.

If you have comments on the draft report, you have until May 12, 2016 to send them in. The best way to comment is through regulations.gov, using Docket ID NRC-2016-0074. You can also mail comments (referencing the Docket ID) to Cindy Bladey, Office of Administration, Mail Stop: OWFN-12-H08, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

If you submit comments in writing or in electronic form, they will be posted on the NRC website and on regulations.gov. The NRC will not edit or remove any identifying or contact information; please don’t include any information you wish to keep private.

We’ve also developed a public communications brochure to help explain the SOARCA project to a wider audience of stakeholders using plain language and more illustrations.

El Nino and NRC Preparedness

F. Paul Peduzzi
Branch Chief
Division of Preparedness and Response

elninoEl Niño is already making itself felt along the West Coast. This phenomenon occurs every two to seven years. It warms sea surface temperatures in the eastern-central Pacific Ocean, shifting average sea level pressure and tropical rainfall in dramatic fashion, and leading to weather pattern changes over parts of the northern and southern hemispheres.

Forecasters expect this year’s El Niño to be one of the strongest ever, based on changes in the sea surface temperatures of the Pacific.

No two El Niño’s are exactly alike, but the pattern generally has these effects:

  • Increased rain and snow across California and the southern United States, with less in the Pacific Northwest and in the Ohio and Tennessee valleys
  • Milder than normal winter across the northern United States
  • More hurricanes than normal in the eastern Pacific and fewer in the Atlantic during hurricane season (June 1 – November 30)

The NRC is alert to potential impacts on our licensees. Facilities such as nuclear power plants are designed to withstand much more severe weather than El Niño typically brings. Nuclear power plants are designed and built to withstand the most severe weather and floods historically reported for their area. Several plants experienced strong El Niño weather patterns in the ‘80s and ‘90s with no major problems.

Following the Fukushima events in Japan in 2011, the plants have enhanced their ability to deal with major floods. For example, additional portable safety equipment, such as pumps and generators, is now available both onsite and offsite.

However, El Niño’s storms could block roadways, making it difficult for plant staff to get to the site and impeding public evacuation routes. Plant operators can use other transportation means to get staff and equipment to the site, if needed. And emergency plans have provisions to clear evacuation routes or use alternate routes. These provisions have been tested before, such as during the Missouri River flooding of 2011

The bottom line? California may be unusually soggy this winter, but the NRC does not expect the current El Niño to cause any safety issues for the nation’s nuclear power plants. As always, we remain vigilant and continue to work with other federal agencies on emergency preparedness and incident response, just in case.

Plenty of Progress to Report on Fukushima-related Enhancements

Scott Burnell
Public Affairs Officer

fukushimaThe NRC’s technical staff, industry executives and a public interest group will brief the Commissioners Thursday on the agency’s efforts to implement what we’ve learned from the Fukushima nuclear accident. The bottom line is the NRC is ahead of schedule on several fronts.

Some of the best news involves U.S. reactors meeting requirements from two of the NRC’s Fukushima-related Orders issued in March 2012. By the end of this spring, almost a quarter of the U.S. fleet will comply with the Mitigation Strategies and Spent Fuel Pool Instrumentation Orders. We expect more than half the fleet will meet those Orders by the end of December, which is a full year before the Orders’ deadline.

Every U.S. reactor will comply with the instrumentation requirements by the December 2016 deadline. Every reactor will also comply by that time with a major Mitigation Strategies requirement – additional, well-protected onsite portable equipment to support key safety measures if an extreme event disables a plant’s installed systems. The U.S. industry has already set up two response centers with even more equipment that can be transported to any U.S. reactor within 24 hours. By the time we say good-bye to 2016, almost every reactor will also have made all modifications needed to use those portable systems. In preparing to meet the deadlines, U.S. reactors have already enhanced their ability to keep the public safe.

About a dozen plants will have made all those modifications except changes closely related to the third Order, which requires Hardened Vents for reactors with designs similar to those at Fukushima. These vents would safely relieve pressure in an emergency and help other systems pump cooling water into the core. All the reactors subject to the Order have completed plans for the first set of vent enhancements or installation of new vents.

The NRC staff finished reviewing these plans earlier this month, ahead of schedule, and issued written evaluations to each plant. The agency is also about ready to issue guidance on how these plants can meet the second part of the Order, which involves an additional vent or other methods to protect the structure surrounding the reactor.

The staff’s presentation will also cover topics including revising the NRC’s rules in these areas, as well as the ongoing effort to re-evaluate flooding hazards for all U.S. nuclear power plants. The NRC’s regional offices will provide their perspective on the overall implementation effort’s progress.

Waves of Uncertainty: The Demise of the Floating Reactor Concept (Part II)

Thomas Wellock
NRC Historian
 

Offshore Power Systems, apparently, did not appreciate that putting land-based reactors out to sea was bound to raise new safety, environmental and regulatory questions. Concerns about ship collisions, off-shore fishing grounds, barge sinking and the challenge of creating a new regulatory process for floating reactors were just some of the unique issues facing regulators.

Even the trade press raised concerns. Nuclear News worried about the “incredibly tangled mass of overlapping jurisdictions, state, national, and international law, inter-agency authority” that included new players such as the U.S. Coast Guard.

Drawing from a 1978 GAO report.

Drawing from a 1978 GAO report.

Events conspired to worsen OPS’s prospects. The oil crisis that began in 1973 made construction financing expensive and slowed electricity consumption. Facing slack demand, PSEG postponed delivery of the first floating plant from 1981 to 1985 and later to 1988. Tenneco backed out of the OPS partnership in 1975. With the entire enterprise threatened, Westinghouse and the Florida Congressional delegation asked the federal government to purchase four plants. But, the prospect of “bailing out” OPS did not appeal to officials in the Ford Administration. The purchase proposal died.

Floating reactors did not solve regulatory or political problems. The production facility in Jacksonville needed an NRC manufacturing license. There were so many technical and regulatory uncertainties that the licensing review ran three years behind schedule. A 1978 report from the U.S. General Accounting Office criticized the NRC for what it believed was an incomplete safety review, particularly for not accounting for impacts on the ocean ecosystem during an accident where a melting reactor core broke through the bottom of the barge.

Local and state opposition to the plant was intense. Nearby counties voted in non-binding referendums 2 to 1 against the Atlantic Generating Station, and the New Jersey legislature refused to introduce a bill to turn the offshore site over to PSEG.

Westinghouse held out hope for a brighter future; PSEG didn’t. In late 1978, the utility announced it canceled its orders for all four of its floating plants. Slack demand, it noted, was “the only reason” for the cancellations. “We simply will not need these units” in the foreseeable future, a utility official admitted.

Others blamed excessive regulation. In March 1979, John O’Leary, a Department of Energy deputy secretary, provided to the White House a “grim—even alarming report,” as one staffer said, that the NRC delays with the OPS license were symptomatic of a larger problem. “It has become impossible to build energy plants in America” O’Leary said, due to excessive environmental regulations and an indecisive bureaucracy. Environmental laws, O’Leary complained, had created “a chain of hurdles which effectively kill energy projects” and damage to the nation’s economy. He wanted presidential action.

Drawing from a 1978 GAO report.

Drawing from a 1978 GAO report.

Events rendered O’Leary’s plea for action moot. Two and a half weeks later the Three Mile Island accident occurred, ending any hope of an imminent industry rebound. The accident raised anew questions about a core melt accident and further delayed the manufacturing license. The NRC did not issue a license until 1982. In 1984, Westinghouse formally abandoned the OPS enterprise, dismantled the Jacksonville facility, and sold its huge crane to China.

Going to sea, OPS discovered, did not allow it to escape the problems that beset nuclear power. A novel technological solution could not overcome public distrust and economic, technical and regulatory uncertainty. We shall see how Russia handles the challenges.

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