United States Nuclear Regulatory Commission - Protecting People and the Environment

ACCESSION #:  9411030366

                              Boston Edison

                      Pilgrim Nuclear Power Station
                             Rocky Hill Road
                      Plymouth, Massachusetts 02360

E.  T.  Boulette, PhD
Senior Vice President-Nuclear
                                                         October 31,1994  
                                                        BECo Ltr #94-118  

US Nuclear Regulatory Commission
Attention: Document Control Desk
Washington, DC 20555

                                                         Docket No 50-293 
                                                       License No. DPR-35

                     10 CFR Part 21 - 30 Day Report

Enclosed with the letter is a 30 day report to the NRC required by 10 CFR
21.21(c)(3)(ii) regarding incorrect trip units (i.e.; long time/short
time/instantaneous (LSIT1) vs long time/short time (LST1)) installed in
safety related electrical feeder breakers, General Electric (GE) Type AK-
50.

The breakers were supplied to Boston Edison Company (BECo) at Pilgrim 
Nuclear Power Station(PNPS) by the General Electric Company, King of
Prussia, PA.

The Significant Safety Hazards determination was made on September 30,
1994. The NRC was notified by fax on October 7, 1994.


                                                  E. T. Boulette, PhD
Enclosure:  10 CFR Part 21--30 Day Report

ETB/GGW/21brakr.doc

cc        Mr. R. Eaton, Project Manager 
          Division of Reactor Projects - I/II
          Mail Stop 14D1
          U. S. Nuclear Regulatory Commission 
          1 White Flint North
          11555 Rockville Pike
          Rockville, MD 20852

          U.S. Nuclear Regulatory Commission
          Region I
          475 Allendale Road
          King of Prussia, PA 19406

          Senior Resident Inspector
          Pilgrim Nuclear Power Station


                      10 CFR Part 21-30 Day Report

     The format of the report follows the requirements found in 10 CFR
Part 21.21(c)(4), paragraphs (i) through(viii). The Part 21 requirement
is quoted in CAPITALIZED BOLD print followed by the BECO response.

          "10 CFR PART 21.21(C)(4):"
          "THE WRITTEN REPORT REQUIRED BY THIS PARAGRAPH SHALL INCLUDE,
BUT NEED NOT BE LIMITED TO, THE FOLLOWING INFORMATION, TO THE EXTENT
KNOWN:"

          "(I) NAME AND ADDRESS OF THE INDIVIDUAL OR INDIVIDUALS          
INFORMING THE COMMISSION.

          E. T. Boulette, Ph.D., Senior Vice-President, Nuclear 
          Boston Edison Company,
          Pilgrim Nuclear Power Station
          600 Rocky Hill Road
          Plymouth, MA 02360

          "(II) IDENTIFICATION OF THE FACILITY, THE ACTIVITY, OR THE
BASIC COMPONENT SUPPLIED FOR SUCH FACILITY OR SUCH ACTIVITY WITHIN
THE
UNITED STATES WHICH FAILS TO COMPLY OR CONTAINS A DEFECT."

          The facility is Pilgrim Nuclear Power Station (PNPS),           
          Docket No 50-293,
          Facility Operating License No. DPR-35 
          
          "(III) IDENTIFICATION OF THE FIRM CONSTRUCTING THE FACILITY OR
SUPPLYING THE BASIC COMPONENT WHICH FAILS TO COMPLY OR CONTAINS A
DEFECT."

          The defective electrical feeder breakers were supplied to PNPS  
          by the General Electric Company, NPSD, King of Prussia, PA.

          "(IV) NATURE OF THE DEFECT OR FAILURE TO COMPLY AND THE SAFETY
HAZARD WHICH IS CREATED OR COULD BE CREATED BY SUCH DEFECT OR
FAILURE TO
COMPLY."

Background:

                Spare PNPS 480V circuit breakers were sent to the 
          General Electric Company (GE), King of Prussia, PA, for
          overhaul and upgrade (dedication) for safety related
          applications. This was specified in BECo PO # RRR001864, items
          3 & 4.
               During shop work testing by PNPS, conducted during pre-
          installation testing but prior to final acceptance, it was
          noted that the trip units installed in the upgraded safety
          related breakers were of the "long time/short time/
          instantaneous" (LSIT1) type rather than the specified long
          time/short time" (LST1) type.
               Although the deviations from the technical requirements of
          the purchase order were properly identified prior to
          installation, the PNPS guidelines for conforming to 10 CFR Part
          21 require that a Substantial Safety Hazard Evaluation (SSH) be
          performed assuming the deviation remains undetected and is
          subsequently installed in the plant.


          Substantial Safety Hazards (SSH) Determination:

                 On September 30, 1994, the following Substantial Safety
          Hazards determination was made after discovery of the incorrect
          trip units during pre-installation testing and prior to final
          acceptance.

                 The worst case random single failure of a safety related
          component would be the loss of the "A" Emergency Diesel
          Generator (EDG).  Because of the deviation contained in the
          upgraded 480 volt feeder breakers, a loss of breaker trip
          coordination would occur from Load Center B2 to Load Center B6. 
          Therefore, an electrical fault in a non-safety related load on
          B6 could cause the "B" train feeder breakers to trip before the
          load breaker.  Consequently, a loss of the "A" EDG would leave
          B6 de-energized.

                 The following is a hypothetical sequence of events
          relating to the subject breakers:
                 o DBA LOCA Inside Containment coincident with loss of    
                   offsite power
                 o EDG "A" fails to start
                 o A non-safety related load on B6 faults causing the B2  
                   feeder breakers to trip

                 The above events would leave B6 and the "A" train ECCS
          de-energized. This means only "B" core spray would be available
          for makeup because the LPCI loop selection components are
          powered from B6. The availability of only one core spray pump
          during a DBA LOCA is an unanalyzed condition.
                 Using the definition of defect contained in Part 21, the 
          evaluated deviation could cause a Substantial Safety Hazard and 
         is, therefore, reportable to the NRC.

         "(V) THE DATE ON WHICH THE INFORMATION OF SUCH DEFECT OR FAILURE
TO COMPLY WAS OBTAINED."

              The determination of a substantial safety hazard regarding
          the incorrect trip units was made on September 30, 1994.

         "(VI) IN THE CASE OF A BASIC COMPONENT WHICH CONTAINS A DEFECT
OR FAILS TO COMPLY, THE NUMBER AND LOCATION OF ALL SUCH COMPONENTS
IN USE
AT, SUPPLIED FOR, OR BEING SUPPLIED FOR ONE OR MORE FACILITIES OR
ACTIVITIES SUBJECT TO THE REGULATIONS IN THIS PART."


              The two (2) breakers supplied to PNPS by GE with incorrect
          trip units were spare PNPS breakers sent to GE for upgrading
          for use in "dedication" for safety related applications.  The
          breakers were specified for the application described in the
          above SSH evaluation.  We know of no other instance of this
          event at any other nuclear power plant. Such information would
          be available from GE, if at all.

         "(VII) THE CORRECTIVE ACTION WHICH HAS BEEN, IS BEING, OR WILL
BE TAKEN; THE NAME OF THE INDIVIDUAL OR ORGANIZATION RESPONSIBLE
FOR THE
ACTION; AND THE LENGTH OF TIME THAT HAS BEEN OR WILL BE TAKEN TO
COMPLETE
THE ACTION."

              Within days of the discovery of the defects, the defective
          breakers were returned to GE for rework to supply the correct
          type of trip unit as specified on the original purchase order. 
          The corrected breakers were returned to PNPS and are now
          installed after successfully passing the required bench and
          load testing.


         "(VIII) ANY ADVICE RELATED TO THE DEFECT OR FAILURE TO COMPLY
ABOUT THE FACILITY, ACTIVITY, OR BASIC COMPONENT THAT HAS BEEN, IS
BEING,
OR WILL BE GIVEN TO PURCHASERS OR LICENSEES."

               Continued diligent receipt inspection and very specific    
           instructions on purchase orders would be the only advice       
           offered by PNPS to other licensees or purchasers of safety     
           related components.


*** END OF DOCUMENT ***

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