Located about 19 miles north of Omaha, OPPD’s Fort Calhoun Nuclear Station is designed to withstand severe natural disasters, including:
An earthquake registering 6.0 on the Richter scale, assuming the plant is at the quake’s epicenter (worst-case scenario)
Tornadic winds up to 500 miles per hour projecting objects such as a telephone pole
1,000-year flood of the Missouri River
Fort Calhoun Station’s “defense in depth” systems include multiple sources of offsite and onsite power. Plant personnel train on and follow written procedures for both normal and emergency operations.
As part of OPPD’s Emergency Response Organization, employees from Fort Calhoun Station and throughout the company participate in regular training drills to help prepare for a serious event at the plant.
OPPD has good working relationships with emergency management personnel at the federal, state, regional and county level.
What Happened in Japan?
Regarding the earthquake, tsunami and resulting nuclear plant problems in Japan, all the reactors operating at the time of the earthquake shut down as designed.
That included those at the Tokyo Electric Power Company’s Fukushima Daiichi plant, 170 miles northeast of Tokyo.
The trouble with the Fukushima reactors started about 20 to 30 minutes after the earthquake hit, when the tsunami waves reached the plant site, cresting at a height of 21 to 30 feet and traveling up to 500 miles per hour.
That caused a loss of offsite power at the plant, resulting in the loss of cooling water for the reactor. A high amount of heat remains within a reactor for some time after shutdown.
Venting of steam from the reactor containment building causes the outside radiation readings to fluctuate.
The plant was designed with a series of redundant safety systems, which greatly reduce the chance of an accident. In addition, the plant’s design includes a “defense in depth” system of barriers to prevent the escape of radioactivity to the environment in the unlikely event of an accident.
In 2006, Fort Calhoun Station underwent a refurbishment outage that reached a scope no power plant in the U.S. had ever attempted.
Containment Building - Constructed of steel-reinforced concrete, with walls almost four feet thick.A one-fourth-inch-thick carbon steel liner on the inside of the Containment Building ensures leak-tightness.
Auxiliary Building - Houses the reactor auxiliaries, including waste-treatment facilities, certain safety components, the control room, emergency diesel generators, and fuel-handling and storage facilities.