View source for L-2006-240, Presentation Material Pertaining to Regulatory Conference on Turkey Point Preliminary White Finding Held on 10/10/06

{{Adams
| number = ML062980382
| issue date = 10/17/2006
| title = Presentation Material Pertaining to Regulatory Conference on Turkey Point Preliminary White Finding Held on 10/10/06
| author name = Jones T
| author affiliation = Florida Power &amp; Light Co
| addressee name = 
| addressee affiliation = NRC/Document Control Desk, NRC/RGN-II
| docket = 05000250
| license number = DPR-031
| contact person = 
| case reference number = EA-06-200, IR-06-015, L-2006-240
| document type = Letter type:L
| page count = 24
| project = 
| stage = Other
}}

=Text=
{{#Wiki_filter:fAttachment                     2 Exempt from Public Disclosure in Accordance with 10CFR2.390 FIPL                                                                              L-2006-240 10CFR50.4 10CFR2.390 ATTN: Document Control Desk                                                     OCT47 2006 U.S. Nuclear Regulatory Commission Washington, DC 20555-0001

==Subject:==
Florida Power and Light Company Turkey Point Unit 3 Docket Nos. 50-250 Presentation Material Pertaining to Regulatory Conference On Turkey Point Preliminary White Finding Held October 10, 2006

==Reference:==
Letter, Mr. C. A. Casto to Mr. J. A. Stall, Turkey Point Nuclear Plant - NRC Integrated Inspection Report 05000250/2006015; EA-06-200, Preliminary White Finding, dated August 24, 2006 On October 10, 2006, a meeting was held between Florida Power and Light Company (FPL) and the Nuclear Regulatory Commission (NRC) in Atlanta, Georgia regarding a Preliminary White Finding discussed in the above referenced letter.
Provided in the attached are copies of the presentation material presented at the October 10, 2006 meeting. Attachment 1 is non-proprietary. Attachment 2 is considered proprietary and contains potentially sensitive security information. FPL requests that Attachment 2 be withheld from disclosure in accordance with 10CFR2.390.
If there are any questions regarding this letter, please contact Jim Connolly at 305-246-6632.
Sincerely Yours, Terry 0. Jones Vice President Turkey Point Nuclear Plant Attachments: 1) Turkey Point Non-Proprietary Presentation Material Regarding Preliminary White Finding 05000250/2006015-01
: 2) Turkey Point Proprietary Presentation Material Regarding Preliminary White Finding 05000250/2006015-01 cc:      NRC Regional Administrator Senior Resident Inspector, USNRC, Turkey Point an FPL Group company

ATTACHMENT 1 Turkey Point Non-Proprietary Presentation Material Regarding Preliminary White Finding 05000250/2006015-01

FPL Nuclear Division   ReguLatory Uonference NVRC Region II, Turkey  Point Nuclear  Plant Turkey Point Nuclear-Plant Unit 3 Loss of Decay Heat Removal Event I

FPL Nuclear Division
* Introductions
* Overview
* Topics of Discussion
         -      Event description
         -      Corrective actions
         -     Thermal-hydraulic analysis of event
         -      Mitigating actions
         -      SDP Analysis
* Closing Remarks 2

FPL Nuclear Division
  "     FPL agrees that it did not comply with requirements of 10 CFR 50.65(a)(4)
* FPL has learned from the loss of decay heat removal event and has taken actions to prevent recurrence
  " FPL evaluation concludes that the change in core damage frequency is less than 1.OE-6/yr 3

F=PL Nuclear Division
  "     Initial conditions
         - Unit 3 in Mode 5
         - Draindown in progress to support reactor head removal
  " Sequence of events
         - While restoring power to 3C 480V load center, spurious undervoltage signal sent to 3A load sequencer
         - 3A load sequencer de-energized 3A 4kV bus, causing loss of running 3A RHR pump
         - 3A EDG re-energized 3A 4kV bus
         - 3A load sequencer does not automatically re-start the 3A RHR pump after loss of offsite power
         - Operator started 3B RHR pump and terminated the event in approximately 9 minutes 4

FPL                         ases Nuclear Division
* Insufficient defense in depth to prevent the event
* The outage risk assessment procedure was insufficient e Experience in maneuvering plant was low with significant shutdown maintenance in progress
* Vendor human error in the configuration of auxiliary switch contacts on a 480V load center breaker that went undetected 5

FP               Immdiae CrrctiveActions Taken0 Nuclear Division
* Senior managementlteam augmented by fleet after event for additional oversight
* Additional reviews of remaining outage schedule performed
* Additional controls of protected plant and switchyard equipment implemented
* Outage schedule changes subject to more rigorous review and approval process 6

FPL                      Long Term Corrective k tions Nuclear Division
  "     Outage risk assessment and control procedure upgraded
          - Responsibility for procedure transferred to Operations
          - PNSC approval required for procedure changes
          - Clearly identifies required protected in-service equipment for higher risk evolutions
          - Provides logic ties for risk significant activities
  "     Use of dedicated and more experienced licensed operators for outage planning and risk assessment (complete) 7

Nuclear Division norrective              Actios (cont'd)
* As-left auxiliary switch contact configuration to be verified by Nuclear Receipt Inspection for 4kV &480V breakers (complete)
* Plant procedures for safety-related breakers revised to check auxiliary switch contact configuration on 4kV &
480V breakers (completed for procedures needed for Fall outage breaker work)
* Applicable plant procedure revised to defeat the sequencer during replacement of 480V load center breakers (complete) 8

Nuclear Division nPLore                  tive cti       (c nt')
  "     Fleet peer reviews of outage schedule (complete)
  " Management challenge of outage schedule (prior to Fall
        -outage)
* Enhanced operator and staff training on shutdown risk assessment (in-progress, complete prior to Fall outage)
* Outage risk management improvements (perform prior to RCS draindown)
          - Pressurizer code safety removed
          - At least two Core Exit Thermocouples available (until just prior to detensioning reactor vessel head)
          - Containment closure ability confirmed 9

    .PL Nuclear Division s           oU -  nnt
* Thermal-hydraulic simulation to determine effects of loss of RHR scenarios
             - Case 1 - No operator actions
             - Case 2 - HHSI feed only
             - Case 3 - HHSI feed & PORV bleed
* Use results to develop FPL SDP event tree
* Using event tree and failure probabilities, calculate change in core damage frequency 10

Nuclear Division ntn           ant Conditions
* 63 hours 50 minutes after shutdown
           - prior to shutdown reactor was at - 50% power for 24 hours
* RCS     being drained to support reactor vessel head lift
* RCS     level near reactor vessel flange
* RCS     temperature ~115 OF
* RCS     vented via:
           - Reactor vessel head vent line with 0.219" diameter orifice
           - Pressurizer vent line 0.742" diameter
* A-RHR in service e B-RHR in standby I1

FPL                         Ifnt        'ii Inditions       (cont'd)
Nuclear Division
* SG secondary side water levels average 84 %wide range
* SG atmospheric steam dumps full open
* Both RWSTs with inventory ~295,000 gal per unit available for HHSI pump use while maintaining NPSH
* Equipment required to mitigate loss of RHR in service
* 2nd qualified Unit Supervisor supervising draindown 12

7PP.                     CL2se V No OperEtorf 3tion Nuclear Division

== Conclusion:==

            -     With no operator action, RHR cooling will be restored simply by starting an RHR pump within approximately 9 hours after event initiation
            -     No core damage with RHR pump start anytime during first 9 hrs of event 13

FPL                       C&se 2       kZ,71 Feeo Only Nuclear Division

== Conclusion:==

                - Able to sustain steady state condition for at least 24 hours with single RWST
                - No core damage for at least 24 hours
                - Sufficient time available to implement RWST inventory management or SG secondary water makeup 14

NPL Nuclear Division Case 3      HHSI Feed & PORVs Bleed e

== Conclusion:==

           -     No core damage for at least 16 hrs using both RWSTs
           -     Sufficient time available to restore RHRor implement RWST inventory management 15

FPL Nuclear Division Th rmal-hydraulicAnalysis Conclusions
* SG reflux cooling will prevent core damage without operator action for at least 9 hours
* The minimum time to start a RHR pump is at least 9 hours (time to boil is overly conservative as the criterion for RHR pump start)
  " Feed & bleed prevents core damage regardless of pressurizer PORVs position
* Managing RWST inventory is proceduralized with options to:
         - Throttle HHSI flow
         - Establish RWST makeup
         - Use opposite unit RWST 16

FPL Nuclear Division e Factors or Additiona:IRC Consideration
"     Base RHR restoration time on NPSH requirements (9hr) rather than core boiling (21 min)
* Failure of PORVs to open for feed & bleed does not result in core damage
* Late restoration of RHR based on additional time provided by SG reflux cooling and feed & bleed
* Additional RWST inventory management strategies to extend availability of HHSI suction source
       -    Throttling HHSI pump flow
       -     Using opposite unit RWST 17

FSPL                 MM. of &lo   73.ZZAs Nuclear Division
* Based on a more detailed SDP analysis FPL estimated the total CDF increase for this event to be approximately 2.OE-7Iyr
* CDF increase below risk significance threshold of 1.OE-6/yr
* FPL concluded this violation to be GREEN 18

Nuclear Division OP ornerstone
"     NRC ROP Cornerstone for this finding should be "Initiating Events"
         -     ROP "Initiating Events" Cornerstone objective: limit frequency of events that upset plant stability and challenge critical safety functions
"     Definitions: NRC Manual Chapter 0308- ROP Basis Document
         -     Initiating Events- "such events include reactor trips due to turbine trips, loss of feedwater, loss of off-site power..."
         -     Mitigating Systems- "include those systems associated with safety injection, residual heat removal, and their support systems..."
"     Event attributable to the loss of 3A 4kV bus normal electrical power to the running 3A RHR pump, not involving a failure attributable to the RHR System 19

FPLCousions Nuclear Division
  "      FPL agrees that it did not comply with requirements of 10 CFR 50.65(a)(4)
   " Review of SDP analysis shows low safety significance with delta CDF < 1.OE-6/yr
   " FPL has taken timely and aggressive corrective actions to prevent recurrence 20

FPL Nuclear Division Regulatory Conference Open Discussion Questions 21

FNPL Nuclear Division Regulatory Conference Final Remarks 22}}