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NRC — Ready for the 2015 Hurricane Season UPDATED

Update: Due to Hurricane Bill, the South Texas Project nuclear power plant, located near Bay City, Texas, has started tropical storm/hurricane procedures. Actions taken include performing a plant walkdown to secure and tie down anything that could be become a projectile missile or flying debris. The plant operator has implemented restrictions for employees to stay inside if winds get above 40 mph. Today, winds are projected to be sustained at 50 mph with gusts up to 60 mph. Both units are at full power unless winds reach speeds above 75 mph, but that is not expected at this time. They have additional staff onsite and supplies (cots, food, water). The resident inspectors are not evacuating and an additional group of NRC inspectors has been on site and will remain so to back up the residents if need be. (At this time the hurricane is not expected to affect River Bend or Waterford nuclear power plants, but the NRC’s Region IV will continue to monitor the projected path.)

Roger Hannah
Senior Public Affairs Officer
Region II

The hurricane season officially began June 1, but this year the Carolina coast experienced a tropical storm named Ana in early May. While Ana produced winds of more than 60 miles an hour near the Brunswick nuclear plant, there was no major damage. It did, however, serve as an early reminder of the NRC’s role in ensuring nuclear plants remain safe during damaging winds and storm surges.

A hurricane as seen by satellite. Be assured, it's not happening now.

A hurricane as seen by satellite. Be assured, it’s not a current photo and is NOT happening now.

The NRC has years of experience with hurricanes and other severe storms. Nuclear facilities were affected by Hurricane Andrew in Florida in 1992, by Katrina in Louisiana in 2005, by Sandy along the East Coast in 2012 and by many others. Although the National Oceanic and Atmospheric Administration predicts fewer storms this year than the historical average, any storm can be dangerous.

How does the NRC oversee the safety of nuclear plants and other facilities during these storms?

The NRC staff monitors tropical storms as they form, and if the projected path is towards the coast, the agency’s regional offices begin continuous tracking. If a storm’s path shows the possibility of it affecting a nuclear plant or other NRC-licensed facility, the NRC collects more information on the storm and NRC resident inspectors check the plant’s preparations. Depending on the projections, additional NRC inspectors may be dispatched to some nuclear plants.

Around 12 hours before predicted hurricane-force winds, nuclear facilities that may be in the path provide the NRC updates and NRC inspectors monitor the plant staff’s actions. Plant procedures require the plant operators to shut the reactor down if winds greater than a certain speed are expected on the plant site.

Nuclear plants are built to withstand all expected local meteorological events, including hurricanes, and actual storms have shown that plants can safely shut down and with little or no damage to important safety equipment.

The NRC stays in contact with plants and NRC inspectors on site as the storm passes over, and the agency has backup systems if regular communications channels are lost.

Once the storm is over, the NRC and FEMA assess damage and make sure local emergency response organizations can resume their normal roles. If the plant shut down, it will only be restarted after the NRC is satisfied there is no damage to safety equipment and emergency response capabilities have been restored.

Fortunately, most tropical storms and hurricanes do not adversely affect nuclear plants, but the NRC is ready in case one does.

A Focus on NRC Annual Assessment Meetings

Prema Chandrathil
Public Affairs Officer
Region III

formal meetingIt’s Spring – and annual assessment meetings are popping up all over. The NRC holds these important meetings every year for every nuclear power plant to provide information about how the plant performed in the previous year.

What happens at these meetings? If you attend, you can expect to hear about NRC inspection activities, how the plant performed from a safety perspective, and how it met NRC requirements, including if there were any violations and, if so, what actions were taken to correct those issues. You would also hear directly from NRC resident inspectors, who are at the plant on a daily basis and know the plant inside and out. They and other specialists inspect the plant to help ensure protection of the public health and safety.

We just posted a short YouTube Video on the subject today. “Three Minutes with an NRC Expert on the Annual Assessment Meetings” can be found here.
community outreachAs the video underscores, annual assessment meetings are not all the same. There are different types, including a formal meeting, an open house and community outreach event. The most common meeting is a formal meeting where the public is invited to observe the interactions between the NRC and plant staff. Open houses are informal and are designed to encourage one-on-one conversations. An example of a community outreach event is where the NRC would staff a booth at a local event in an effort to talk to more folks. The type of meeting will vary depending on the plant’s performance, community feedback and local interest.

No matter the format of the meeting, the public will have an opportunity to not only hear about the plant’s performance and NRC inspection efforts but also ask questions, make comments and talk to the NRC staff.

A common misconception is that these meetings are transcribed — they are not. The basis for the NRC’s discussion is the annual assessment letters issued by the NRC to individual plants. These letters are documented and publically available. You can find them on the NRC website.

3 minutes with AA_1The NRC continues to reach out in an effort to inform people about what the agency does, how we regulate and how a particular plant is doing in meeting NRC rules and regulations. We are committed to protecting public health and safety, and strive to be open and responsive in these annual assessment meetings.

If you are interested in any upcoming public meeting you can check out the public meeting schedule and review the meeting notice as well as the press release.

We hope you’ll check out the video to learn more.

Heeding the Sirens – Despite A Few Mishaps

Victor Dricks
Senior Public Affairs Officer
Region IV

sirenResidents of St. Charles Parish, Louisiana, who live within the 10-mile emergency planning zone for the Waterford 3 nuclear plant, got an unexpected benefit last week when 37 emergency sirens were sounded for a tornado warning.

St. John Parish is similarly protected by 36 sirens. But thousands of other residents who live in surrounding parishes have no sirens.

The reason: The NRC and FEMA work together to make sure the commercial nuclear power plants in this country have sirens around their sites to alert the public in the event of a serious incident. Various federal, state and local agencies also have emergency notification systems they can use to alert the public to a variety of emergencies — including one at a nuclear plant.

“The people of St. Charles Parrish got the benefit of the emergency sirens that surround Waterford 3,” said Ron Perry, the Director of Emergency Preparedness for Homeland Security in St. Charles Parish.

Each nuclear plant is required to exercise its emergency plan with offsite authorities at least once every two years – which includes checking the siren systems. This helps make sure the plant operator, and state and local authorities, can implement their emergency plans if needed. If all goes according to plan, the interface among all these agencies is seamless.

But things do not always go as planned.

Last year, while preparing for an upcoming emergency exercise at the plant, the National Weather Service inadvertently alerted the public around the Cooper Nuclear Station in Brownville, Neb., of an unspecified emergency at the plant. The weather service was updating the wording of messages stored in a computer system when someone pushed the wrong button. This sent an advisory to various news media organizations and some members of the public.

The weather service quickly realized what happened and sent a message explaining the error to the media 13 minutes later. But, the mishap received plenty of news coverage.

Unfortunately, this was the second recent incident about emergencies at the Cooper nuclear plant. On July 24, Nebraska Public Power District workers were working on a computer system that controls sirens in Nemaha County when a false alarm was broadcast.

There have been two other similar incidents at Region IV nuclear plants in recent memory:

Last summer, Pacific Gas & Electric Co. workers were upgrading their siren system around Diablo Canyon when they inadvertently activated one at 3:30 in the afternoon. It sounded continuously for 14 minutes before workers were able to deactivate it remotely. It took 10 minutes before county officials sent out an advisory noting the error. Some people vented their anger about all the confusion on the county’s Facebook page, and several local TV stations and the Associated Press carried reports about the incident.

sirenNot a week later, something similar happened in Washington State. During a training class at the state Emergency Operations Center, a staffer inadvertently faxed a partially filled out form for an Alert (the second lowest level of nuclear emergency) at Columbia Generating Station. The fax went to nine different emergency management agencies, including one in Canada. A second fax was quickly sent out correcting the error.

The NRC is primarily concerned with the reliability of sirens. The NRC tracks the performance of licensee alert and notification systems by measuring the number of successful siren tests conducted quarterly at each plant. These types of incidents are embarrassing to all involved and in each instance corrective actions have been taken to minimize the chance of future mishaps.

But the bottom line is that residents in the communities around nuclear power plants need to heed the warning, and trust the emergency alert systems. A few false alarms should not change their response. If you hear a siren, or get a text message on your phone announcing an emergency, please heed the warning.

Droning On Over Nuclear Power Plants

Monika Coflin
Technical Assistant
Division of Security Policy

Drones, or unmanned aerial vehicles, have been in the news lately. Last fall, unidentified drones breached restricted airspace over 13 of France’s 19 nuclear power plants in a seemingly coordinated fashion. In January, a drone crashed onto the lawn of the White House. And this week, a drone was found on the roof of the Japanese prime minister’s office.

PrintDrones may be fun toys, but they pose a number of concerns. They can be used to conduct surveillance to gather intelligence about facility security. They can also be used to deliver payloads that could include explosives. While the majority of drones currently in use are relatively small, larger ones are becoming available that could possibly deliver payloads capable of causing damage to facilities that are not hardened.

Security experts haven’t yet identified who was responsible for the French flyovers, but with the prices of drones falling and their popularity rising, the potential threat will likely continue to grow.

There are ways to detect and intercept drones, such as jamming radio signals or using helicopters to pursue encroaching drones. Chinese scientists are developing a laser weapon that can detect and shoot down small, low-flying aircraft, and interception drones have the ability to drop nets over intruding drones. However, there are many legal issues that challenge the use of these techniques.

The Federal Aviation Administration (FAA) has a long-standing “Notice to Airmen” warning pilots not to linger over nuclear power plants. The FAA has also issued guidelines on where users should not fly drones, but the industry is largely unregulated as more companies look to use the relatively new technology in their businesses. The FAA has been working to craft a comprehensive regulatory framework for drones, following calls from Congress and the President, and recently issued draft regulations for the commercial use of drones.

PrintPresident Obama likened the drone industry to cyberspace, which has brought new technologies that U.S. laws are still trying to catch up to.

“These technologies that we’re developing have the capacity to empower individuals in ways that we couldn’t even imagine 10-15 years ago,” the President said, pledging to work to create a framework that “ensures that we get the good and minimize the bad.”

Given the evolving nature of technology and the need to balance the threat with the potential benefits of drones, the NRC is actively engaging with the departments of Homeland Security, Energy, and Defense to move this government collaboration effort forward. For example, we have reached out to the FAA to examine available legal and regulatory options, and attended inter-agency meetings to learn about how other agencies are addressing potential impacts from drones.

In addition, NRC will participate in a U.S.-initiated drone working group under the nuclear counterterrorism umbrella with the governments of France and the United Kingdom. The NRC has provided, and will continue to provide, pertinent information on this topic in a timely manner to its licensees to ensure continued safe and secure operations.

REFRESH — What is a Reactor Trip and How Does it Protect the Plant?

Samuel Miranda
Senior Reactor Systems Engineer

Note: Last week, the Prairie Island nuclear power plant “tripped.” So, it seemed like a good time to revisit a blog post we did two years ago on the subject.

refresh leafOn occasion, a nuclear power plant will “trip,” meaning something happened that caused the reactor to automatically shut down to ensure safety. In other words, a trip means a plant is doing what it’s supposed to do. Let’s look at the term a bit more closely.

Key operating parameters of a nuclear power plant, such as coolant temperature, reactor power level, and pressure are continuously monitored, to detect conditions that could lead to exceeding the plant’s known safe operating limits, and possibly, to damaging the reactor core and releasing radiation to the environment.

If any of these limits is exceeded, then the reactor is automatically shut down, in order to prevent core damage. In nuclear engineering terms, the automatic shutdown of a nuclear reactor is called a reactor trip or scram. A reactor trip causes all the control rods to insert into the reactor core, and shut down the plant in a very short time (about three seconds).

How do control rods do their job?

pwr[1]The control rods are composed of chemical elements that absorb neutrons created by the fission process inside the reactor. They are placed methodically throughout the nuclear reactor as a means of control. For example, as the control rods are moved into the reactor, neutrons are absorbed by the control rods and the reactor power is decreased. Inserting them all at the same time shuts down the reactor. Control rods can also be inserted manually, if necessary.

The plant operator then determines the reason for the trip, remedies it and, when it’s determined to be safe, restarts the reactor. So, while not common, a reactor trip is an important way to protect the components in a nuclear power plant from failing or becoming damaged.

REFRESH is an occasional series where we re-run previous blog posts. This post originally ran in December 2012.

 

 

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