BYRON, Ill. - Exelon Nuclear has added seven mobile, high-volume diesel-driven pumps at its nuclear energy facilities, among thousands of equipment purchases, upgrades and validations completed at Exelon's 10 plants, including the Byron Generating Station, in the year following the tragic earthquake and tsunami in Japan.
Exelon technical experts have verified readiness of more than 1,700 other pieces of equipment; inspected more than 1,900 flood barriers and seals; and invested more than 43,000 worker hours checking and testing equipment and procedures that might be needed in an emergency.
Those actions represent just a portion of the inspections, upgrades and other work undertaken by Exelon Nuclear following the Fukushima-Daiichi disaster. The company operates the largest fleet of commercial nuclear facilities in the U.S., with 17 reactors at 10 sites.
Within a week of the March 11, 2011 events, teams of engineers and technical experts from Exelon Nuclear and others in the industry traveled to Japan to provide expertise and to begin understanding as many lessons as possible from the experience. The primary lesson: expect the unexpected, and prepare for the unimaginable.
Learnings from Fukushima have translated into extensive reviews of equipment, structures and procedures at Byron Station, purchases of additional backup emergency equipment, updates of emergency procedures, and additions to emergency training.
"At Byron Station we recognize that nuclear power is special and unique, and our top priority is operating our facility with the highest safety standards," said Tim Tulon, Byron Station site vice president.
"Since last March, we have taken the learnings from Fukushima, critically assessed our operations and taken immediate actions," said Mike Pacilio, president and chief nuclear officer of Exelon Nuclear. "We have additional safety measures planned for Exelon and the entire U.S. nuclear industry in the months ahead with additional guidance being issued by the U.S. Nuclear Regulatory Commission. We take pride in always being a learning organization dedicated to the safety of our facilities."
Among other tasks completed over the past 12 months, Exelon Nuclear engineers and experts have:
• Revised more than 1,300 safety procedures and guidelines, and created new ones, based on Fukushima lessons.
• Verified the capability of all sites to withstand the most severe floods for their areas, and are in the process of re-evaluating base assumptions about maximum historical flooding.
• Broadened operator training to incorporate lessons from Fukushima.
• Inspected and validated the seismic supports and restraints for thousands of pieces of equipment and pipes.
In February, Exelon and other U.S. nuclear operating companies unanimously agreed to purchase or order additional safety equipment for their plants by March 31. This includes emergency and portable equipment such as diesel-driven pumps, electric generators, hoses, fittings, communications gear and other equipment.
Well before the events at Fukushima, Byron Station had multiple physical barriers and layers of backup safety systems to ensure safe operations even in extreme events, including floods, hurricanes, tornadoes, and earthquakes. Equipment purchases and work over the past year has strengthened those barriers and systems, and enhancements will continue for years.
Byron Station is protected from flooding by watertight doors, elevation of equipment above flood levels and specially engineered flood barriers. Byron Station can automatically and safely shut down and keep the fuel cooled even without electricity from the grid, using massive backup power generators that have second, third and fourth layers of backups. Reactors and other critical components are protected by concrete walls up to four-feet thick. Byron Station undergoes frequent emergency training and exercises involving government emergency response agencies at all levels.
Byron Station's emergency operating procedures are constantly tested, challenged and simulated to ensure they will work properly when needed. Such drills are overseen by the NRC with NRC inspectors stationed at all U.S. nuclear facilities on a full-time basis.
Over the last 12 months, the U.S. nuclear industry has pooled resources to ensure the lessons from Japan are systematically gathered, analyzed and implemented. The process identified short- and long-term actions that further increase the margin of safety at U.S. nuclear facilities.
"Exelon Nuclear is dedicated to full transparency," said Pacilio. "We know that the more the public knows about the safety of the U.S. nuclear industry, the more confident they feel about nuclear power as a source of safe, abundant and clean energy."