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Monthly Archives: April 2014

The NRC Keeps Watch Over Comanche Peak During Chapter 11 Proceedings

Lara Uselding
Region IV Public Affairs Officer
 

The owner/operator of the Comanche Peak nuclear power plant — Luminant Generation Company LLC – told us that its parent company, Energy Future Holdings (EFH), has filed for Chapter 11 bankruptcy. Chapter 11 provides time for a business to sort out its financial problems.

cpThis is not the first time an action like this has involved a nuclear plant. The owner of the Diablo Canyon plant went through a bankruptcy in 2001, and, in the 1980s, the Seabrook plant went through a similar process.

The NRC has been actively monitoring the situation since EFH told the Securities and Exchange Commission last year it may have difficulties meeting debt obligations. NRC staff has looked at any potential impacts on plant safety and security, the decommissioning fund, and the implementation of post-Fukushima action items. We determined the plant continues to be sufficiently funded.

Based on NRC management visits to the Texas plant and monthly calls and meetings with company executives at the NRC Region IV office, the NRC has been assured EFH’s financial issues will not have a negative impact on the safe operation of the plant.

Staff from NRC’s regional office in Arlington, Texas, will continue to conduct inspections and assessments to ensure public health and safety is maintained. They will also evaluate whether the financial conditions are impacting plant staffing, maintenance activities and emergency preparedness capabilities.

Moving forward, the NRC has reminded the company  it must continue to meet requirements of its license. For example, EFH/Luminant must have a financial support agreement of $250 million to ensure operating and maintenance costs for the two reactors can be met for a year. And EFH and Luminant must inform the NRC prior to transferring significant funds — greater than 10 percent of total accounts — away from Luminant.  Once a new corporate entity is established the firm must notify the NRC to begin the license transfer process.

The plant is in compliance with our decommissioning funding assurance requirements, and the NRC will work with the bankruptcy authorities to ensure decommissioning funds are insulated from creditor claims.

Two NRC resident inspectors live in the local community and work at the plant. They are the agency’s eyes and ears at the plant and their daily oversight helps to ensure the plant continues to be operated safely, and protects public health and the environment.

A New Look at Reactor Decommissioning

David McIntyre
Public Affairs Officer
 

 Four nuclear power plants closed in 2013 and another is expected to shut down later this year. That puts decommissioning in the spotlight – so the NRC has produced a new video explaining how it’s done.

map_Decommissioning_8By way of background, the owners of Crystal River 3 in Florida, Kewaunee in Wisconsin, and San Onofre 2 and 3 in California already have taken the first steps toward decommissioning their plants. They’ve certified that they permanently ceased operations and removed the fuel from the reactors into their spent fuel pools. Their licenses no longer allow them to operate the reactors.

The owners of Vermont Yankee will do the same when that plant stops operating as scheduled late this year.

The companies then have up to two years to develop and submit decommissioning plans – called the post-shutdown decommissioning activities report, or PSDAR. The report includes a description and a schedule for decommissioning activities and their estimated cost. The report also includes a discussion of why any anticipated environmental impacts have already been reviewed in previous reports on the plant. Crystal River submitted its report last December.

Plant owners typically combine two decommissioning approaches: DECON, in which the plant is dismantled and the site cleaned up to the NRC’s specifications, and SAFSTOR, maintaining the plant as is for a period of time before final cleanup. Waiting allows the radioactivity at the site to decay, making cleanup easier. (A third approach, entombing the reactor in place, has never been used by NRC licensees.)

Two years before the license is to be terminated, the plant owner submits its License Termination Plan to the NRC. The NRC surveys the site to verify the cleanup has been successful before terminating the license (or amending it if spent fuel is still stored there).

We hope you’ll take a few minutes to view the new video. Even more information about the decommissioning process can be found on the NRC website.

Untangling Foreign Involvement in New Reactors

Scott Burnell
Public Affairs Officer
 

For the second time in two years, the NRC’s administrative law judges have offered a decision on what role overseas companies can play in building and operating new U.S. nuclear power plants.

stpIn this most recent case, the Atomic Safety and Licensing Board concluded that Toshiba’s participation in the South Texas Project new reactor project south of Houston is acceptable.

When Congress created the Atomic Energy Act, it included language that prohibits “foreign ownership, control or domination” of nuclear facilities. In an August 2012 decision, the Board examined a company applying for a new reactor at the Calvert Cliffs site in Maryland. That decision concluded the company was 100 percent foreign-owned and therefore ineligible for a reactor construction and operation license.

The South Texas case presents a different set of facts. The company applying for two new reactors, Nuclear Innovation North America, is a joint venture. A U.S. utility, NRG Energy, owns about 90 percent of NINA. Toshiba’s North American subsidiary owns the rest.

The NRC has previously approved joint ownership of U.S. reactors where the foreign partner owned more than 10 percent. In the South Texas application, however, the NRC technical staff determined in May 2013 that Toshiba’s overall financial support of the project equaled improper control or domination.

The Board’s decision on the South Texas new reactor application explores some previously uncharted territory. Legal precedent on foreign ownership almost exclusively refers to transferring the licenses of existing reactors. Those license transfers largely have been made in the context of ownership percentage. The Board’s decision applies the terms “control or domination” to the South Texas arrangement.

The Board relied on the NRC’s existing standard review plan to resolve the “control or domination” question. The ultimate decision is based on the South Texas application’s corporate ownership structure and other measures. The Board concluded that those measures meet the review plan’s aim of ensuring U.S. control of safety-related decisions.

Both the NRC staff and the groups opposing the South Texas new reactors have the opportunity to appeal the Board’s decision to the five-member Commission in charge of the NRC. A final decision on the South Texas proposal will take a couple more years due to ongoing technical reviews.

Closing In on Finishing the ESBWR Design Review

Michael Mayfield
Director, Advanced Reactor and Rulemaking Program
 

After a lot of technical discussions, the NRC is ready to take the next step in considering whether GE-Hitachi’s Economic Simplified Boiling Water Reactor meets our standards for U.S. use.

esbwrWe’ve been reviewing this new reactor design for several years. This design includes new types of safety systems that would use gravity to direct cooling water into the core during an emergency, even when electrical power is lost. Our review path took a major turn in 2011.

In March of that year we issued our technical conclusions on the design. The NRC then drafted a regulation that would approve the ESBWR, but later in 2011, we received additional information related to the steam dryer design that made us pause. (The steam dryer prevents excess moisture from damaging the plant’s turbine.)

We spent 2012 and 2013 making sure we had all the necessary information from GE-Hitachi on the ESBWR steam dryer design.  We’ve completed the review of the additional steam dryer design information and now have what we need to complete the design certification.

The NRC expects to seek public comment on a supplemental proposed certification rule next month and to send a draft final rule to the five-member Commission in July. This process could lead to final certification of the ESBWR later this year.

Utilities interested in new reactors can reference NRC-certified designs to simplify parts of their license reviews. The utilities applying for licenses to build ESBWRs, Detroit Edison in Michigan and Dominion in Virginia, will have to update their applications to account for any changes to the design.

Our letter to GE-Hitachi on these developments is available in the NRC’s electronic document database.

 

 

NRC Science 101 — Different Types of Radiation

Donald Cool
Senior Radiation Safety Advisor

science_101_squeakychalkIn earlier Science 101 posts, we talked about what makes up atoms, chemicals, matter and ionizing radiation. In this post, we will look at the different kinds of radiation.

There are four major types of radiation: alpha, beta, neutrons, and electromagnetic waves such as gamma rays. They differ in mass, energy and how deeply they penetrate people and objects.

The first is an alpha particle. These particles consist of two protons and two neutrons and are the heaviest type of radiation particle. Many of the naturally occurring radioactive materials in the earth, like uranium and thorium, emit alpha particles. An example most people are familiar with is the radon in our homes.

The second kind of radiation is a beta particle. It’s an electron that is not attached to an atom (see previous blog post). It has a small mass and a negative charge. Tritium, which is produced by cosmic radiation in the atmosphere and exists all around us, emits beta radiation. Carbon-14, used in carbon-dating of fossils and other artifacts, also emits beta particles. Carbon-dating simply makes use of the fact that carbon-14 is radioactive. If you measure the beta particles, it tells you how much carbon-14 is left in the fossil, which allows you to calculate how long ago the organism was alive.

The third is a neutron. This is a particle that doesn’t have any charge and is present in the nucleus of an atom. Neutrons are commonly seen when uranium atoms split, or fission, in a nuclear reactor. If it wasn’t for the neutrons, you wouldn’t be able to sustain the nuclear reaction used to generate power.

The last kind of radiation is electromagnetic radiation, like X-rays and gamma rays. They are probably the most familiar type of radiation because they are used widely in medical treatments. These rays are like sunlight, except they have more energy. Unlike the other kinds of radiation, there is no mass or charge. The amount of energy can range from very low, like in dental x-rays, to the very high levels seen in irradiators used to sterilize medical equipment.

fordoncools101As mentioned, these different kinds of radiation travel different distances and have different abilities to penetrate, depending on their mass and their energy. The figure (right) shows the differences.

Neutrons, because they don’t have any charge, don’t interact with materials very well and will go a very long way. The only way to stop them is with large quantities of water or other materials made of very light atoms.

On the other hand, an alpha particle, because it’s very heavy and has a very large charge, doesn’t go very far at all. This means an alpha particle can’t even get through a sheet of paper. An alpha particle outside your body won’t even penetrate the surface of your skin. But, if you inhale or ingest material that emits alpha particles, sensitive tissue like the lungs can be exposed. This is why high levels of radon are considered a problem in your home. The ability to stop alpha particles so easily is useful in smoke detectors, because a little smoke in the chamber is enough to stop the alpha particle and trigger the alarm.

Beta particles go a little farther than alpha particles. You could use a relatively small amount of shielding to stop them. They can get into your body but can’t go all the way through. To be useful in medical imaging, beta particles must be released by a material that is injected into the body. They can also be very useful in cancer therapy if you can put the radioactive material in a tumor.

Gamma rays and x-rays can penetrate through the body. This is why they are useful in medicine—to show whether bones are broken or where there is tooth decay, or to locate a tumor. Shielding with dense materials like concrete and lead is used to avoid exposing sensitive internal organs or the people who may be working with this type of radiation. For example, the technician who does my dental x-rays puts a lead apron over me before taking the picture. That apron stops the x-rays from getting to the rest of my body. The technician stands behind the wall, which usually has some lead in it, to protect him or herself.

Radiation is all around us, but that is not a reason to be afraid. Different types of radiation behave differently, and some forms can be very useful. For more information on radiation, please see our website.

Don Cool, who holds a Ph.D. in radiation biology, advises the NRC on radiation safety and for 30 years has been active on international radiation safety committees.
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