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Event Notification Report for July 11, 2007

U.S. Nuclear Regulatory Commission
Operations Center

Event Reports For
07/10/2007 - 07/11/2007

** EVENT NUMBERS **


43475 43479

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Power Reactor Event Number: 43475
Facility: CRYSTAL RIVER
Region: 2 State: FL
Unit: [3] [ ] [ ]
RX Type: [3] B&W-L-LP
NRC Notified By: RICHARD SWEENEY
HQ OPS Officer: JOHN MacKINNON
Notification Date: 07/07/2007
Notification Time: 11:51 [ET]
Event Date: 07/07/2007
Event Time: 11:03 [EDT]
Last Update Date: 07/10/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(3)(xiii) - LOSS COMM/ASMT/RESPONSE
Person (Organization):
JAY HENSON (R2)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
3 N Y 100 Power Operation 100 Power Operation

Event Text

LOSS OF SAFETY PARAMETER DISPLAY SYSTEM (SPDS) DUE TO PLANNED MODIFICATION

"At 11:03 hours EST, on July 7, 2007, the Plant Information Computer System (PICS) was removed from service to perform a planned modification to install and test a Standard Digital I&C System Platform (DICSP) infrastructure and to update the network configuration of PICS. The expected duration of PICS inoperability is approximately 24 to 36 hours. PICS provides monitoring and communications capability for plant data systems including the Emergency Response Data System (ERDS), Safety Parameter Display System (SPDS), Plant Process Computer System (PPCS), Emergency Response Computer Logger (ERCO-1), Meteorological Data link system and the Inadequate Core Cooling Monitor (ICCM). The loss of PICS requires alternate methods, as described in plant procedures, to be used for the above described functions. Therefore, appropriate assessment of plant conditions, notifications and communications can still be made, if required, during the time that PICS is inoperable. This report is being made in accordance with 10 CFR 50.72(b)(3)(xiii) which is any event that results in a major loss of emergency assessment capability, offsite response capability or offsite communications capability. As previously stated, alternate means remain available to assess plant conditions, make notifications and accomplish required communications, as necessary. An additional notification will be provided when PICS operability is restored.

"The NRC Resident Inspector has been notified."

* * * UPDATE FROM RICHARD SWEENEY TO JOE O'HARA AT 1653 ON 7/8/07 * * *

"Engineering change (EC) of PICS continues. Testing of the installed modifications is now in progress. As stated above, alternate means remain available to assess plant conditions, make notifications, and accomplish required communications, as necessary. Testing of the EC and EC turnover is expected to be completed on 07/09/2007. The plant computers, including SPDS, are presently running providing plant data thus are available but not operable."

The licensee notified the NRC Resident Inspector.

Notified R2DO(Henson)


* * * UPDATE FROM RICKY RAWLS TO JOHN KNOKE AT 2043 ON 7/10/07 * * *

"Crystal River Unit 3 initially reported removal of its Plant computer systems from service for planned modification on 07/07/07 at 11:51 and made the required notification in accordance with 10 CFR 50.72(b)(3)(xiii). The Engineering change associated with the Safety Parameter Display System (SPDS) and the Plant Information Computer System (PICS) has been completed and the systems are currently running providing data. Modification testing has been completed and the systems are considered operable. The compensatory measures put in place to assure appropriate assessment of plant conditions, notifications and communications have been terminated."

Licensee also stated that the ERDS system is now operable.

The licensee notified the NRC Resident Inspector. Notified R2DO (Hopper)

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Power Reactor Event Number: 43479
Facility: PILGRIM
Region: 1 State: MA
Unit: [1] [ ] [ ]
RX Type: [1] GE-3
NRC Notified By: DAVID NOYES
HQ OPS Officer: MARK ABRAMOVITZ
Notification Date: 07/10/2007
Notification Time: 22:55 [ET]
Event Date: 07/10/2007
Event Time: 19:54 [EDT]
Last Update Date: 07/10/2007
Emergency Class: NON EMERGENCY
10 CFR Section:
50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL
50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Person (Organization):
JOHN ROGGE (R1)

Unit SCRAM Code RX CRIT Initial PWR Initial RX Mode Current PWR Current RX Mode
1 A/R Y 50 Power Operation 0 Hot Shutdown

Event Text

MAIN TURBINE TRIP CAUSING A REACTOR SCRAM

"During a planned power reduction to support thermal backwash of the main condenser, an automatic reactor scram resulted from a main turbine trip. The cause for the turbine trip is currently under investigation. Following the reactor scram, the expected reactor level shrink resulted in valid group 2, Reactor Building Ventilation, and group 6, Reactor Water Cleanup System isolations. All safety systems and equipment functioned as designed. A schedule for plant restart has not yet been determined."

All control rods fully inserted and no safety relief valves lifted from the scram. Minimum level after the scram was -10 inches.

Decay heat is being removed using the main turbine bypass valves to the main condenser and maintaining level using normal reactor feed water. The plant is using the normal shut down electrical lineup and slowly cooling down (currently at 820 psi).

The licensee notified the NRC Resident Inspector.

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Thursday, March 29, 2012