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 Start dateTitleDescriptionTopic
ENS 4823927 August 2012 13:00:00Discovery of After-The-Fact Emergency Condition - Alert - High Co2 Concentration in a Safe Shutdown Area

At 0927 EDT on 08/28/2012, it was identified that access to a table H-1 Safe Shutdown Area had been prohibited and that an ALERT had not been declared as required by Surry EPIP-1.01, EAL HA 3.1. At 0900 EDT on 08/27/2012, Electrical Maintenance was performing a surveillance on the Unit 2 Cable Vault and Cable Tunnel Low Pressure CO2 System. A high CO2 level was observed using portable gas detection equipment and access to the space was prohibited for a period of approximately 20 minutes. This report is being made in compliance of VPAP-2802, section 6.3.3(h), which states that a one hour report is required if an Emergency Action Level (EAL) is exceeded, the basis for the emergency class no longer exists at the time of discovery, and no other reasons exist for an emergency declaration. The licensee will notify the NRC Resident Inspector and Virginia Emergency Management Agency.

  • * * RETRACTION ON 7/15/13 AT 1342 EDT FROM BARRY GERBER TO DONG PARK * * *

Based upon initial air monitor readings, EN #48239 reported that an oxygen deficient condition existed in a Table H-1 area for approximately 20 minutes. When the initial information was presented to the Shift Manager on 08/28/2012, it was determined that a one-hour report should have been declared in accordance with EPIP-1.01, Emergency Action Level HA 3.1, which states that an ALERT condition exists if 'access to a Table H-1 area is prohibited due to toxic, corrosive, asphyxiant or flammable gases which jeopardize operation of systems required to maintain safe operations or safely shutdown the reactor.' Since the ALERT condition was not recognized on 08/27/2012, a one-hour report was deemed necessary. A root cause evaluation reviewed the oxygen monitor data and determined that the maximum time of oxygen deficiency was approximately 8 minutes. Operator Time Critical Actions were reviewed to determine whether prohibition of access to the Cable Vault and Cable Tunnel for approximately 8 minutes would jeopardize operation of systems required to maintain safe operations or safely shutdown the reactor. No specific references to activities within this area were identified. Therefore, this event was determined not to be an Alert. The root cause evaluation also noted that Operations was notified of the test, administrative control was established for the CO2 Tank shutoff valve, an Electrician was posted in the control room to notify Operations of alarms associated with the test, a fire watch posted, and the test areas were posted and evacuated. The brief period of time the condition existed did not result in a threat to safe plant operation or the health of plant personnel. Therefore, this event was determined not to be an Unusual Event in accordance with EPIP-1.01, Emergency Action Level HU 3.1, which states, 'report or detection of toxic, corrosive, asphyxiant or flammable gases that have or could enter the Owner Controlled Area in amounts that can affect normal plant operations.' This notification is being made to retract the report made on 08/28/12 based on the above discussion. The NRC Resident (Inspector) has been notified. Notified R2DO (Nease).

Safe Shutdown
Time of Discovery
Fire Watch
ENS 428887 October 2006 22:01:00Manual Scram Due to Unusual Noise in Turbine Building

The main turbine cross-under safety relief valves lifted for no known reason and blew siding off the side of the Unit 2 Turbine building. This siding hit the feeder lines to the A & C Reserve Station Service Transformers (RSSTs). The operator manually scrammed the plant due to swings in steam generator level and unusual noise coming from the turbine building . Unit 2 shutdown currently de-energized A & C Reserve Station Transformers, which effects D & E transfer buses. This also effects 1J bus, which is de-energized, and 1H & 2J buses which are energized with #1 diesel and #3 diesel. Decay heat removal is being performed thru the SG PORV's and auxiliary feedwater system, with forced cooling from the "B" RCP. Safety related systems are available if required. Notified USDA (A. Jimenez) in addition to the other agencies already identified. The licensee notified the NRC Resident Inspector, as well as State and local agencies.

  • * * UPDATE ON 10/8/2006 AT 05:45 FROM MIKE CHRIS TO ABRAMOVITZ * * *

The site terminated the Alert at 05:40 due to having the "A" RSST in service with bus 1J being powered from its normal power supply. No damage was found from the displaced siding with the exception of the "C" RSST (which should be repaired around noon). The "C" RSST is currently tagged out for maintenance. The licensee notified the NRC Resident Inspector, state, and local governments. Notified: R2DO (Decker), R4DO (Pick), NRR (Dyer, Weber, Quay), IRD (Blount, Wilson), R2 (McCree), DHS (Gray), FEMA (Dunker), DOE (Steve Bailey), EPA (Allison), USDA (Dean Giles), and HHS (Lt. Smith).

  • * * RETRACTION ON 10/16/06 AT 1724 FROM L. WHEELER TO M. ABRAMOVITZ * * *

At 1827 hours on 10/07/06, an Emergency Notification System (ENS) notification was made for an Alert declaration at Surry Power station. The steam discharge from the turbine system safety valves that had lifted caused pieces of siding from the turbine building to dislodge and come in contact with two phases of the overhead bus for the 'A' and 'C' reserve station service transformers (RSST). The basis for the declaration was the Emergency Action Level (EAL) Tab K-11: 'Notification of missile impact causing damage to safety-related equipment or structures'. Upon further review, the RSSTs were determined not to be safely-related equipment. Therefore, the conditions for an Alert emergency did not exist and the notification is being retracted. A notification will be made to the Virginia Department of Emergency Management. This is being reported In accordance with 10 CFR50.72, (b) (2) (xi). As noted in EN# 42890, conditions for a Notification of Unusual Event (NOUE) did exist at the time of the Alert notification. The licensee notified the NRC Resident Inspector. Notified the R2DO (Henson).

Reserve Station Service Transformer
ENS 4077022 May 2004 01:46:00Unanalyzed Condition Due to Auxiliary Feedwater Not Being in Compliance with Justification for Continued Operation (Jco).

At 2146 hours on 05/21/04, Unit 2 entered a 30 Hr. clock to Cold Shutdown (CSD) in accordance with T.S.3.0.1 due to Auxiliary Feedwater (AFW) not being in compliance for Continued Operation (JCO) SC 03-002 configuration. Auxiliary Feedwater was declared inoperable at 2146 hours. During post trip recovery, Emergency Procedure, 2-ES-0.1, directed that the six (6) AFW motor operated valves (MOVs) be checked opened after securing the AFW Pumps. This is contrary to the AFW JCO, which requires four (4) MOVs out of six (6) to be closed for AFW to remain Operable. At 0040 hours on 5/22/04 the correct valve alignment in accordance with the JCO was established and the 30 hour TS 3.0.1 clock was exited. This event is reportable in accordance with 10CFR50.72(b)(3)(ii)(B); any event or condition that results in the Station being in an unanalyzed condition that significantly degrades plant safety. The NRC resident has been notified. The licensee found out about this event today during event investigation. See Surry Unit 2 events 40769, 40768 and 40771.

  • * * RETRACTION FROM WOODZELL TO CROUCH ON 05/25/04 @ 2347 EDT * * *

The following information was received from the licensee via facsimile: At 1506 hours on 5/22/04, Surry Power Station made an 8-hour Non-Emergency Notification in accordance with 10CFR50.72 (b)(3)(ii)(B) for an unanalyzed condition due to Auxiliary Feedwater (AFW) not being aligned in accordance with Justification for Continued Operation (JCO) SC 03-002 for 2 hours and 54 minutes following a reactor trip. (Event Number 40770). Upon further analysis, this event was determined not to be immediately reportable. Based on calculations performed by Dominion Nuclear Safety Analysis in Engineering Transmittal ET NAF-04-0045, Rev 0, a risk-based period of time was calculated to allow operations personnel a defined period of time to realign the AFW system in accordance with this JCO. Operators must not exceed 150 hours to restore the acceptable JCO configuration during all modes where AFW is required to be operable. Since the amount of time the system was not in the JCO alignment was less than 150 hours, plant risk increase was maintained less than the limits specified in Regulatory Guide 1.177. This notification is being made to retract the report made on 5/22/04 based on the above discussion. The NRC resident has been notified. The NRC Headquarters Operations Officer notified R2DO (Ayres).

Unanalyzed Condition