Semantic search
| Entered date | Event description | |
|---|---|---|
| ENS 47502 | 6 December 2011 17:07:00 | On 12/06/2011 at approximately 1306 CST, a major offsite underground communications line was severed, cutting telephone lines to Clinton Power Station. The lost communications include the Health Physics Network (HPN), Emergency Notification System (ENS) and the ability to send Emergency Response Data System (ERDS) data to the NRC. Alternate communications have been established with the NRC and other agencies. This event is reportable due to the major loss of emergency assessment capability per 10CFR50.72 (b)(3)(xiii). The time to repair the lines and restore communications is unknown at this time. The NRC Resident Inspector has been notified.
The communication lines have been repaired and HPN, ENS, and ERDS have been restored. Notified R3DO (Skokowski). |
| ENS 46771 | 20 April 2011 18:05:00 | During the performance of operator rounds in the Lake Screenhouse Safe Shutdown System (SX) pump rooms, two water tight doors were left opened simultaneously during the room checks. These two doors opened simultaneously (which) allowed for communication between the Division 1 SX room and Division 2 SX pump room. The operator was in constant attendance in the Division 2 SX pump room during the performance of the equipment checks. During site review, it was determined that a flood in either the Division 1 or Division 2 SX pump rooms would not be isolated to the initiating room, but potentially affect both trains of SX. This could result in a loss of cooling for both Residual Heat Removal systems, therefore, a condition that could have prevented fulfillment of a safety function under 10CFR50.72(b)(3)(v)(B). The NRC Senior Resident has been notified. Offsite power is normal and emergency diesel generators are operable and available. * * * RETRACTION FROM ED TIEDEMANN TO PETE SNYDER ON 6/8/11 AT 1141 EDT * * * A subsequent plant barrier impairment evaluation consistent with Exelon Procedure CC-AA-201, 'Plant Barrier Control Program' has determined that no loss of safety funct ion would have occurred. Each of the following door functions and related postulated events were reviewed for impact: ventilation; flooding, internal and external; high energy line breaks; missiles; radiation protection; and fires. For the condition with the SX pump room water tight doors being open with an operator in the area, the conclusion is an SX division remains protected to ensure that in any of the evaluated events the safety function of SX has been maintained. The licensee has notified the NRC Resident Inspector. |
| ENS 45965 | 1 June 2010 11:45:00 | On June 1, 2010, at 0900 hours CDT, Clinton Power Station removed the Technical Support Center (TSC) ventilation system from operation to facilitate preventive maintenance to replace charcoal media in the ventilation system filter assembly. This work is expected to last approximately 3 days, during which the TSC ventilation system will be unavailable. If an emergency is declared requiring TSC activation during this period, the TSC will be staffed and activated using existing emergency planning procedures unless the TSC becomes uninhabitable due to ambient temperature, radiological, or other conditions. If relocation of the TSC becomes necessary, the Station Emergency Director will relocate the TSC staff to an alternate TSC location in accordance with applicable site procedures giving first consideration to the Control Room. TSC facility leads have been made aware of this contingency. This notification is being made in accordance with 10CFR50.72 (b) (3) (xiii) due to the potential loss of an emergency response facility (ERF) because of the unavailability of the emergency filtration mode of the ventilation system. An update will be provided once the TSC ventilation has been restored to normal operation. The NRC Resident Inspector has been notified.
At 1300 hours CDT, the charcoal media in the ventilation system filter assembly has been replaced and post maintenance testing completed satisfactorily. The TSC ventilation system is now available. The licensee has notified the NRC Resident Inspector. Notified R1DO (Pelke). |