Stichting Laka

Event Report Forms (ERFs) are filed to the IAEA. Sometimes there are multiple event reports, updating the rating, the event description. Here you only see the latest event report

ERF send date: Thu, 23-07-1998
ERF description: On 24 June 1998, with the reactor operating at 99% of rated thermal power, the plant lost offsite power due to severe weather, including lightning strikes to the electrical switchyard and a tornado that damaged the switchyard and turbine building roof. The reactor automatically shut down as a result of the loss of electrical power and emergency diesel generators (EDGs) provided power to safety equipment. The licensee declared an ALERT emergency classification as a result of the event. The reactor was cooled down at a reduced rate of approximately 5.6C (10 deg F) per hour due to the unavailability of reactor coolant pumps, which require offsite electrical power. On 25 June 1998, with offsite electrical power still unavailable, the licensee conservatively declared one of the two EDGs inoperable with respect to the plant Technical Specifications after the air temperature in the EDG room slightly exceeded the maximum design temperature. Although the EDG was declared inoperable, it operated normally and continued to supply power to its associated safety equipment until offsite electrical power was restored. Due to the reduced reactor cooldown rate, the licensee was unable to comply with the requirements of the Technical Specifications, and reported the deviation to the USNRC. The air temperature in the room continued to fluctuate near the maximum design temperature throughout the event. One source of offsite electrical power was restored to the plant during the evening of 25 June 1998, and the emergency was terminated during the afternoon of 26 June 1998.
Justification: The event was initially rated as level 0/below scale in accordance with Table II of the INES Users Manual, as an event with a high initiator frequency and full safety function availability. The rating was escalated to level 1 due to the duration of the unavailability of offsite electrical power and the tornado damage to plant structures.
ERF rating date: 10-07-1998
ERF contact person: R.J. BARRETT
ERF address: United States
ERF affiliation: USNRC, EMERGENCY RESPONSE BRANCH, OFFICE FOR ANALYSIS AND EVALU

This map shows a selection of reports from nuclear and radiological incidents stored in the IAEA NEWS-database.
Locations are estimates. Contact us if a location is wrong.
The map shows a maximum of 100 incidents. If hundred incidents or more are within the map, the yellow perimeter indicates from where events are excluded. Drag or zoom the map to explore different areas.

Power Reactor Research Reactor Radwaste Facility Enrichment Facility Radiation Source Irradiation/Accelerator Facility Transportation

Fuel Fabrication Fuel Reprocessing Research Facility Mining/Milling Radioisotope Processing/Handling Facility Other