NRC MONITORING AN EVENT AT BYRON NUCLEAR PLANT
The Nuclear Regulatory Commission Region III office in Lisle, Illinois, has activated its incident response center and entered monitoring mode due to an Unusual Event declared at the Byron nuclear power plant Unit 2. The event was declared due to a loss of offsite power at 10:18 a.m. CT. The two-unit plant is operated by Exelon Generation Co., located in Byron, Ill., 17 miles southwest of Rockford.
The plant automatically shut down in response to the loss of offsite power. Smoke was seen from an onsite station transformer. When the plant’s fire brigade responded, no evidence of fire was found. The diesel generators are currently supplying power to plant equipment. Steam is currently being released from the non-nuclear side of the plant to aid in the cooling process. The steam release does not present a threat to the public.
NRC resident inspectors at the plant are monitoring the situation in consultation with staff in the Region 3 office in Lisle, Ill.
An Unusual Event is the lowest of four levels of the NRC’s emergency classification system.
Feb. 2 AP Update:
CHICAGO (AP) -- The U.S. Nuclear Regulatory Commission says the amount of radioactive tritium released in steam to cool a reactor during a shutdown at an Illinois nuclear plant was not enough to present a danger to the public.
Agency spokeswoman Viktoria Mitlyng (MIT'-ling) says preliminary calculations indicate that the radiation dose from Monday's release at the Byron Generating Station was less than 0.001 (one one-thousandth) percent of the NRC's annual limit. That amount is thought to be safe to workers and the public.
The Byron plant is about 95 miles northwest of Chicago.
Even less tritium escaped in a 2010 steam release at the Braidwood nuclear plant about 50 miles southwest of Chicago.
Final data will be available to the public after the Commission conducts a special investigation.
Jan. 31 Update: BYRON (WIFR) -- The emergency classification at the Byron Nuclear Plant has been lifted.
It is no longer considered an "Unusual Rvent" which is the lowest of four classifications. We've also learned, some water pumps at the station turned off when the unit two reactor lost power and then came back on without being manually reset. The Nuclear Regulator Commission is conducting a special inspection into why this happened. Also, the Illinois' Emergency Management Agency is collecting water and soil samples to check for contamination, from when steam was released. Those results should be available within a few days.
This extra steam is the plant's way of releasing pressure. IEMA spokespeople say they don't expect to find dangerous levels of tritium. They’re also taking water and vegetation samples; they should get results back in a few days.
Exelon has since traced the failure at reactor two to an electrical insulator in a switchyard. The insulator will be sent to a lab for analysis and officials hope to replace it by tonight. As soon as power is restored the low-level emergency classification will be lifted. No word when unit two will be back up and running.
IEMA Environmental Personnel Collect Samples Near Byron Nuclear Power Plant: Agency Continues to Monitor Plant Conditions
through Remote Monitoring System
SPRINGFIELD (IEMA) -- Environmental monitoring personnel from the Illinois Emergency Management Agency (IEMA) are collecting samples around the Byron Nuclear Power Plant today to confirm that a steam release during the Unusual Event on Jan. 30 poses no hazard to the public. While IEMA officials do not expect to find hazardous levels of radioactive tritium, the sampling will allow the agency to verify if tritium is present in the environment and, if present, at what levels.
“While we don’t expect to find harmful levels of tritium from the steam release at Byron, I believe it’s prudent to collect these samples and verify what levels are present,” said IEMA Director Jonathon Monken. “We have no reason to believe that harmful levels were released, but we have a duty to the public to ensure what, if any, tritium from the steam release is in the environment around the plant.”
IEMA personnel are collecting water and vegetation samples. Some of the samples will be in the same locations as routine sampling conducted by IEMA within the past month. The samples will be taken to the agency’s laboratory in Springfield for analysis. Results should be available within a few days.
Monken said reactor and environmental analysts at IEMA have been closely monitoring data on conditions at the plant since the Byron Unit 2 reactor tripped Monday morning due to a loss of off-site power. The data is received through the agency’s state-of-the-art remote monitoring system, which continuously relays information about conditions within the reactor as well as analyzes releases through the plant’s stacks and from detectors located in a two-mile radius around the plant.
The agency’s Resident Inspector for the Byron plant has been providing IEMA analysts with additional information about plant conditions and utility actions and is monitoring the utility’s recovery activities.
BYRON (WIFR) -- An update on the emergency situation at the Byron Nuclear Plant. Engineers now know what caused the plant to lose power and shut down one of its reactors.
That overpowering sound coming from the Byron Nuclear Plant is nothing to worry about. But it's startling enough to Patricia Carter, who was prepared to take iodide tablets. A supply she stores in case of a nuclear meltdown.
"My first thought was, what do I take out of here, where do I go."
The plant remains under "an unusual event" classification. It's the lowest emergency ranking set by the U.S. Nuclear Regulatory Commission. Exelon says Unit Two was shutdown when a failed piece of equipment in the switch-yard triggered a power outage.
"When I found out it was nothing, I just went down, it was a relief believe me," says Carter.
And it's a good thing there wasn't an imminent threat.
"We responded out to the plant and we were stuck held up in security for a while until they could release us and let us through," says Byron Fire Chief Galen Bennett.
Byron firefighters weren't needed. So they left after about ten minutes.
As for that sound, it's steam helping reduce pressure in the plant. It does contain tritium, a radioactive form of hydrogen.
"That's at very low levels and it dissipates quickly so it's not an issue for our workers here on site or for people in the community," says Byron Nuclear Plant Communication Manager Paul Dempsey.
Unit one remains up and running. ComEd says you won't notice any disruption to your power. That's because the Nuclear Plant provides power to a grid, not individual communities. No word when Unit Two will be fully operational.
A little before 10:30 this morning the Byron Nuclear Plant lost power and unit two went offline. Plant engineers are still trying to figure out why it happened.
The plant has safeguards that go into effect automatically when emergencies arise. Fire crews were dispatched to the plant immediately to make sure that workers and neighbors weren't in any danger and back up generators kicked on. The station also started to depressurize itself by releasing steam. We’re told some of that steam contains a mildly radioactive isotope called tritium.
Today’s outage is considered an ''unusual event,” which is the lowest of four emergency classifications used at nuclear plants.
BYRON (WIFR) -- Operators at Byron Generating Station declared an Unusual Event at 10:18 a.m. CT, due to the loss of offsite power and Unit 2 coming offline.
The nuclear facility’s diesel generators activated as designed to provide power to the facility when there is a loss of offsite power to the facility. The facility remains in a safe condition. Station engineering experts are looking into the cause of the loss of offsite power.
Byron Station is designed to depressurize to reduce steam pressure as part of the many redundant safety systems built into the facility. Steam from the unit is released through safety relief valves that are specifically designed for this purpose. The steam, which will evaporate quickly, contained expected levels of tritium. Local residents may see or hear the steam release in progress, which will continue throughout the day until the unit cools down. These types of station releases are regulated by the Nuclear Regulatory Commission.
There is no health or safety impact to workers or to the public from the release, and Exelon Nuclear has notified all appropriate local, state and federal officials of the Unusual Event.
An Unusual Event is the lowest of four emergency classifications established by the U.S. Nuclear Regulatory Commission.
Tritium is an isotope of hydrogen with a weak level of radioactivity. It is formed naturally in the upper atmosphere, is a component of rain and is found in virtually all of earth’s surface water. Tritium is produced in greater concentrations in commercial nuclear reactors and is routinely discharged into the environment under strict regulatory guidelines. Tritium eventually breaks down into helium.
Byron’s Unit 1 continues to supply clean electricity to Exelon customers.
Byron Generating Station is in Ogle County, Ill., about 25 miles southwest of Rockford.