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Event Notification Report for May 15, 2002

                         
                    U.S. Nuclear Regulatory Commission
                              Operations Center

                              Event Reports For
                           05/14/2002 - 05/15/2002

                              ** EVENT NUMBERS **

38915  38919  

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|Power Reactor                                    |Event Number:   38915       |
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| FACILITY: COOK                     REGION:  3  |NOTIFICATION DATE: 05/13/2002|
|    UNIT:  [] [2] []                 STATE:  MI |NOTIFICATION TIME: 02:39[EDT]|
|   RXTYPE: [1] W-4-LP,[2] W-4-LP                |EVENT DATE:        05/12/2002|
+------------------------------------------------+EVENT TIME:        23:01[EDT]|
| NRC NOTIFIED BY:  BRADDOCK D. LEWIS            |LAST UPDATE DATE:  05/14/2002|
|  HQ OPS OFFICER:  LEIGH TROCINE                +-----------------------------+
+------------------------------------------------+PERSON          ORGANIZATION |
|EMERGENCY CLASS:          NON EMERGENCY         |ANTON VEGEL          R3      |
|10 CFR SECTION:                                 |                             |
|ARPS 50.72(b)(2)(iv)(B)  RPS ACTUATION - CRITICA|                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
+-----+----------+-------+--------+-----------------+--------+-----------------+
|UNIT |SCRAM CODE|RX CRIT|INIT PWR|   INIT RX MODE  |CURR PWR|  CURR RX MODE  
|
+-----+----------+-------+--------+-----------------+--------+-----------------+
|                                                   |                          |
|2     A/R        Y       100      Power Operation  |0        Hot Standby      |
|                                                   |                          |
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                                   EVENT TEXT                                   
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| AUTOMATIC REACTOR TRIP DUE TO AN INSTRUMENTATION RACK POWER SUPPLY
FAILURE   |
| WHICH CAUSED A STEAM GENERATOR FEEDWATER REGULATING VALVE TO FAIL
CLOSED     |
|                                                                              |
| The following text is a portion of a facsimile received from the licensee:   |
|                                                                              |
| "DC Cook Unit 2 tripped from full power due to an instrumentation rack power |
| supply failure on 05/12/02 [at] 2301.  All control rods fully inserted.  No  |
| Safety Injection was required.  The Unit 2 Reactor is stable and             |
| subcritical.  The Steam Generator Stop Valves were manually closed by the    |
| Operating Crew to stabilize RCS Temperature in accordance with Plant         |
| operating procedures.  Reactor Coolant Temperature is being maintained       |
| manually on the Steam Generator Atmospheric relief valves at No-Load T(ave)  |
| in accordance with plant procedures."                                        |
|                                                                              |
| "This instrumentation rack power supply failure caused the #21 Steam         |
| Generator Feed Regulating Valve to fail CLOSED.  The Unit 2 Reactor          |
| subsequently TRIPPED on Low Level in [the] #21 Steam Generator coincident    |
| with Low Feedwater Flow.  Several control systems were affected by the       |
| control rack instrumentation failure:  Pressurizer Pressure Control -        |
| transferred control to manual and restored Pressurizer pressure, Pressurizer |
| Level Control - transferred control to manual and restored Pressurizer water |
| level, Refueling Water Sequence - Manually transferred Charging Pump Suction |
| to the RWST.  Manual Operator response maintained and restored critical      |
| plant parameters in MANUAL to normal parameter values."                      |
|                                                                              |
| "Unit 2 entered Technical Specification 3.0.3 for 34 minutes because the     |
| control system failures and plant system response temporarily caused the     |
| Boration Flow paths from both the Refueling Water Storage Tank and Boric     |
| Acid Storage Tanks to become INOPERABLE.  Both Boration flow paths were      |
| subsequently returned to OPERABLE status by manual Operator action."         |
|                                                                              |
| "The Reactor trip is reportable in accordance with 10 CFR 50.72(b)(2)(iv)(B) |
| as an actuation of the Reactor Protection System (RPS) when the Reactor was  |
| critical.  The Reactor TRIP was the result of an instrumentation rack power  |
| supply failure and was not part of any preplanned test or evolution."        |
|                                                                              |
| The licensee stated that the unit is currently stable in Mode 3 (Hot         |
| Standby).  The reactor coolant pumps are available for primary system        |
| transport control.  Pressurizer level and pressure control are in manual.    |
| Normal charging and makeup are available, but the automatic function of the  |
| refueling water sequence is not available.  The auxiliary feedwater pumps    |
| automatically started as expected and are currently being utilized to supply |
| water to the steam generators.  Secondary steam is being dumped to           |
| atmosphere.  There is no evidence of steam generator tube leakage, and       |
| containment parameters are as expected.  There were no safety injections and |
| none were required, and none of the primary power-operated relief valves     |
| lifted.                                                                      |
|                                                                              |
| The licensee notified the NRC resident inspector.                            |
|                                                                              |
| ****UPDATE 5/14/02 At 13:20 From B. Bates To R. Laura****                    |
|                                                                              |
| The initial report stated that the reactor coolant temperature is being      |
| maintained manually on the steam generator atmospheric relief valves at      |
| no-load Tave in accordance with plant procedures.  Temperature control was   |
| actually established in automatic on the steam generator atmospheric relief  |
| valves and remains in automatic.                                             |
|                                                                              |
| A statement was made in the original report that Unit 2 entered Technical    |
| Specification 3.0.3 for 34 minutes. Upon further review, there was no        |
| requirement to enter Technical Specification 3.0.3. The control system       |
| failures and plant system response caused the boration flowpaths from both   |
| the Refueling Water Storage Tank (RWST) and Boric Acid Storage Tanks to      |
| become inoperable. Therefore, the Unit  was actually in Technical            |
| Specification 3.1.2.2 actions (a)and (b) concurrently. This did not          |
| constitute an entry into Technical Specification 3.0.3 because entry into    |
| both actions is not prohibited.                                              |
|                                                                              |
| Another statement was made that both boration fiowpaths were subsequently    |
| returned to operable status by manual operator action. The boration flowpath |
| from the boric acid storage tanks was returned to operable. However, after   |
| further investigation, it was determined that the boration flow path from    |
| the RWST remained inoperable due to the inability of the refueling water     |
| sequence to automatically initiate.  The NRC Resident Inspector was          |
| notified.                                                                    |
|                                                                              |
| Notified R3DO R. Gardner.                                                    |
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|General Information or Other                     |Event Number:   38919       |
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| REP ORG:  ABB, INC.                            |NOTIFICATION DATE: 05/14/2002|
|LICENSEE:  ABB, INC.                            |NOTIFICATION TIME: 08:05[EDT]|
|    CITY:  FLORENCE                 REGION:  2  |EVENT DATE:        05/14/2002|
|  COUNTY:                            STATE:  SC |EVENT TIME:             [EDT]|
|LICENSE#:                        AGREEMENT:  Y  |LAST UPDATE DATE:  05/14/2002|
|  DOCKET:                                       |+----------------------------+
|                                                |PERSON          ORGANIZATION |
|                                                |DANIEL HOLODY        R1      |
|                                                |ROBERT HAAG          R2      |
+------------------------------------------------+RONALD GARDNER       R3      |
| NRC NOTIFIED BY:  PATRICK O'NEAL (fax)         |DAVE LOVELESS        R4      |
|  HQ OPS OFFICER:  LEIGH TROCINE                |VERN HODGE           NRR     |
+------------------------------------------------+                             |
|EMERGENCY CLASS:          NON EMERGENCY         |                             |
|10 CFR SECTION:                                 |                             |
|CCCC 21.21               UNSPECIFIED PARAGRAPH  |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
|                                                |                             |
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                                   EVENT TEXT                                   
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| NOTIFICATION OF A POTENTIAL DEFECT REGARDING K-LINE MECHANISM FAILURES
TO    |
| CHARGE AND CLOSE                                                             |
|                                                                              |
| The following text is a portion of a facsimile received from ABB, Inc.:      |
|                                                                              |
| "In August of 2001, Southern California Edison, San Onofre Nuclear           |
| Generating Station, reported and submitted an operating mechanism for        |
| evaluation to the ABB, Inc., Florence, SC Breaker Manufacturing Facility due |
| to suspected shipping damage causing 'failure to charge' symptoms.  The      |
| mechanism was a special configuration of the base 709774 Model '05'          |
| mechanism manufactured in 10/1997.  This mechanism was in a Nuclear          |
| Safety-Related application.  The mechanism was received by the factory in    |
| September of 2001, and the reported failure mode was not duplicated in       |
| Florence.  However, under the auspices of a 'refurbishment,' ABB, Inc.,      |
| personnel performed an evaluation of critical characteristics for parts that |
| could be contributory to the failure mode described herein."                 |
|                                                                              |
| "On 7 February 2002, Ameren - Union Electric's Sioux Generating Plant        |
| reported a failure to charge and close of a Model '05' K-Line K-600S circuit |
| breaker (Serial Number 935461B--010496) manufactured 04/96.  This breaker    |
| was purchased for a Non-1E application.  The cause of the breaker failure    |
| was determined to be a culmination of energy utilization deficits.           |
| Specifically, the condition of lubricant (Anderol 757), the surface and      |
| finish of parts critical to the charging operation, and the interaction of   |
| critical latching surfaces serve to impede the ability of the mechanism to   |
| fully charge through the end of the charge cycle."                           |
|                                                                              |
| "In March 2002, Dominion Virginia Power's Surry Nuclear Station reported the |
| failure to charge and close of a 1993 K-800M (Serial Number                  |
| 865613B033--010793).  In this case the breaker was refurbished in the hopes  |
| of alleviating the symptoms, only to find they returned a short time after   |
| return to service.  ABB, Inc., had already initiated Part 21 reporting       |
| proceedings as this latest failure was announced, and the Florence Breaker   |
| Manufacturing Facility is awaiting a customer report to verify the failure   |
| mode."                                                                       |
|                                                                              |
| "In all cases, the end user is observing a failure to charge and/or close in |
| electrically operated mechanisms.  These failures are due to one of the      |
| following two scenarios:"                                                    |
|                                                                              |
| "1.  A failure to charge and close, either mechanically or electrically,     |
| until the needed energy is supplied to rotate the charging cam over the      |
| center-point into a fully charged position -- either by mechanical vibration |
| or operator rotation of the charging cam."                                   |
|                                                                              |
| "2.  A failure to close where the above scenario does not exist but the      |
| fully charged mechanism does not close due to the fact that the primary      |
| close latch does not fully clear in response the secondary close latch       |
| actuation."                                                                  |
|                                                                              |
| "With the introduction of the Model '07' mechanism in December 1998, while   |
| maintaining backward compatibility with pre-existing models, ABB has         |
| facilitated improvements to be incorporated into every mechanism that is     |
| built at the Florence Breaker Manufacturing Facility.  ABB recognizes that   |
| this failure mode may exist in any K-Line circuit breaker manufactured or    |
| having undergone mechanism repair, refurbishment, or replacement between     |
| January 1, 1988 and December 31, 1998 and, therefore, recommends that        |
| utilities address this issue at the next available maintenance interval.     |
| This includes any 'spare' K-Line mechanisms manufactured during the afore    |
| determined time frame that may be in stock."                                 |
|                                                                              |
| "Three equally viable options are available to rectify this situation. They  |
| are, listed in order of ABB preference, most desirable first:"               |
|                                                                              |
| "1.  Replacement of suspect K-Line operating mechanism (ABB part number      |
| 709774T##) with a Model '07' mechanism (ABB part number 716785T##).  This    |
| option will require the purchase of an Engineering Qualification Report      |
| Addendum so that 1E dedication traceability is maintained."                  |
|                                                                              |
| "2.  Upgrade of suspect K-Line operating mechanism to a Model '07' mechanism |
| utilizing one of ABB upgrade kits, numbers 716659T03 through T10.  This      |
| option will require the purchase of an Engineering Qualification Report      |
| Addendum so that 1E dedication traceability is maintained."                  |
|                                                                              |
| "3.  Improvement of suspect K-Line operating mechanism within the original   |
| model class utilizing ABB repair kit number 716659T01 or T02."               |
|                                                                              |
| "Work required by the options listed above should only be performed by       |
| personnel trained and/or authorized by ABB, Inc.  ABB is available to        |
| perform the work in the Florence, South Carolina, factory or perform         |
| in-factory training if non-ABB personnel are to be used or contracted."      |
|                                                                              |
| "Note:  If work associated with options 2 or 3 above is performed by         |
| personnel outside of the Florence, SC factory, one minor configuration       |
| change must be noted.  During mechanism re-assembly, technicians must        |
| relocate the washer (ABB part number 650351A57) from its original location   |
| on the control device side on the Primary Close Latch Pivot Pin (ABB part    |
| number 702883D00) to the charging motor side."                               |
|                                                                              |
| "ABB [plans to] notify all Nuclear Utility Companies."                       |
|                                                                              |
| Call the NRC operations officer for ABB, Inc., contact information.          |
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