IR 05000282/2007004
| ML073170686 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 11/13/2007 |
| From: | Richard Skokowski Region 3 Branch 3 |
| To: | Wadley M Nuclear Management Co |
| References | |
| IR-07-004 | |
| Download: ML073170686 (32) | |
Text
November 13, 2007
SUBJECT:
PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2 NRC INTEGRATED INSPECTION REPORT 05000282/2007004; 05000306/2007004
Dear Mr. Wadley:
On September 30, 2007, the U. S. Nuclear Regulatory Commission (NRC) completed an integrated inspection at your Prairie Island Nuclear Generating Plant, Units 1 and 2. The enclosed report documents the inspection findings which were discussed on October 4, 2007, with you and other members of your staff.
This inspection examined activities conducted under your license as they relate to safety and to compliance with the Commission rules and regulations and with the conditions of your license.
The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel.
Based on the results of this inspection, two licensee-identified violations were identified and are listed in Section 4OA7 of this report.
If you contest the subject or severity of a Non-Cited Violation, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S.
Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, D.C.
20555-0001, with a copy to the Regional Administrator, U.S. Nuclear Regulatory Commission-Region III, 2443 Warrenville Road, Suite 210, Lisle, IL 60532-4352; the Director, Office of Enforcement, U.S. Nuclear Regulatory Commission, Washington, D.C. 20555-0001; and the Resident Inspector Office at the Prairie Island Nuclear Generating Plant. In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter and its enclosure will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRC's document system (ADAMS), accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Richard A. Skokowski, Chief Branch 3 Division of Reactor Projects Docket Nos. 50-282; 50-306;72-010 License Nos. DPR-42; DPR-60; SNM-2506 Enclosure:
Inspection Report 05000282/2007004; 05000306/2007004 w/Attachment: Supplemental Information
cc w/encl:
D. Cooper, Senior Vice President and Chief Nuclear Officer M. Sellman, President and Chief Executive Officer Regulatory Affairs Manager J. Rogoff, Vice President, Counsel & Secretary Nuclear Asset Manager State Liaison Officer, Minnesota Department of Health Tribal Council, Prairie Island Indian Community Administrator, Goodhue County Courthouse Commissioner, Minnesota Department of Commerce Manager, Environmental Protection Division Office of the Attorney General of Minnesota
SUMMARY OF FINDINGS
IR 05000282/2007004, 05000306/2007004; 07/01/07 - 09/30/07; Prairie Island Nuclear
Generating Plant, Units 1 and 2; Routine Baseline Inspection Report.
This report covers a three month period of baseline resident inspection and announced baseline inspection by regional inspectors. The inspection was conducted by the resident inspectors and inspectors from the Region III office. No findings of significance were identified.
The significance of most findings is indicated by their color (Green, White, Yellow, Red) using Inspection Manual Chapter 0609, Significance Determination Process (SDP). Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 4, dated December 2006.
A.
Inspector-Identified and Self-Revealed Findings No findings of significance were identified.
Licensee-Identified Violations
Two violations of very low safety significance, which were identified by the licensee, have been reviewed by the inspectors. Corrective actions taken or planned by the licensee have been entered into the licensees corrective action program. The violations and corrective action tracking numbers are listed in Section 4OA7 of this report.
REPORT DETAILS
Summary of Plant Status
Unit 1 operated at or near full power throughout the inspection period.
Unit 2 operated at or near full power throughout the inspection period except that power was reduced to about seven percent from September 28 through October 1, 2007, for condenser cleaning and turbine balancing.
REACTOR SAFETY
Cornerstone: Initiating Events, Mitigating Systems, and Barrier Integrity
1R04 Equipment Alignment
.1 Partial Walkdowns
a. Inspection Scope
The inspectors performed partial system equipment alignment inspection samples comprised of in-plant walkdowns of accessible portions of trains of risk-significant equipment associated with the Mitigating Systems and Barrier Integrity cornerstones.
The inspectors conducted the inspections during times when the trains were of increased importance due to the redundant trains or other related equipment being unavailable. The inspectors also reviewed documents entering deficient conditions associated with equipment alignment issues into the corrective action program verifying that the licensee was identifying issues at an appropriate threshold and entering those issues into their corrective action program in accordance with the corrective action procedures.
The inspectors utilized the valve and electric breaker checklists, where applicable, to verify that the components were properly positioned and that support systems were lined up as needed. The inspectors also examined the material condition of the components and observed operating parameters of equipment to verify that there were no obvious performance deficiencies. The inspectors reviewed outstanding work requests, work orders (WOs), and corrective action program action requests (CAPs)associated with the operable trains to verify that those documents did not reveal issues that could affect the completion of the available train(s) safety functions. The inspectors used the information in the appropriate sections of the Updated Safety Analysis Report (USAR) to determine the functional requirements of the systems.
The inspectors completed two inspection samples by verifying the alignment of the following trains:
- D1 diesel generator during the unavailability of D2 diesel generator for planned testing on July 9, 2007; and
- D6 diesel generator during the unavailability of D5 for troubleshooting on July 16, 2007.
Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
.2 Complete Walkdowns
a. Inspection Scope
During the week of August 13, 2007, the inspectors performed a detailed in-plant walkdown of the alignment and condition of the Unit 2 component cooling system. The component cooling system is a risk-significant and safety-related mitigating system that removes heat from major components in the Nuclear Steam Supply System under normal conditions and from all components associated with removal of reactor core decay heat under accident conditions. The inspectors also reviewed CAPs associated with equipment alignment issues to verify that the licensee was identifying issues at an appropriate threshold and entering them into their corrective action program in accordance with the licensees corrective action procedures.
The inspectors used applicable alignment checklists and plant drawings to verify that system components were properly positioned to support the completion of system safety functions and to verify that the as-found system configuration matched the configuration specified in the system alignment checklists and plant drawings. The inspectors examined the material condition of the components, such as pumps, supports and snubbers, motors, valves, instrumentation, controls, bus relays, and electrical panels.
Where applicable, the inspectors examined outstanding design issues, temporary modifications, and operator workarounds. Where applicable, the inspectors verified that tagging clearances were appropriate and attached to the specified equipment. The inspectors reviewed outstanding WOs, work requests, and CAPs associated with the trains to determine if any degraded conditions existed that could affect the accomplishment of the systems safety functions. The inspectors referred to the Technical Specifications (TS), USAR, and other design basis documents to determine the functional requirements of the systems and verified those functions could be performed if needed. Key documents used by the inspectors in conducting this inspection are listed in the Attachment to this report.
This review constituted the completion of one inspection sample.
b. Findings
No findings of significance were identified.
1R05 Fire Protection Area Walkdowns
a. Inspection Scope
The inspectors conducted in-office and in-plant reviews of portions of the licensees Fire Hazards Analysis and Fire Strategies to verify consistency between these documents and the as-found configuration of the installed fire protection equipment and features in the fire protection areas listed below. The inspectors selected fire areas for inspection based on their overall contribution to internal fire risk as documented in the Individual Plant Examination of External Events, their potential to impact equipment that could initiate a plant transient, or their impact on the plants ability to respond to a security event. The inspectors assessed the control of transient combustibles and ignition sources, the material and operational condition of fire protection systems and equipment, and the status of fire barriers. In addition, the inspectors reviewed CAPs associated with fire protection issues to verify that the licensee was identifying issues at an appropriate threshold and entering them into their corrective action program in accordance with corrective action procedures.
The following 10 fire areas were inspected by in-plant walkdowns supporting the completion of 10 fire protection zone walkdown samples:
- Fire Area 22, Bus 111 Switchgear Room, on July 5, 2007;
- Fire Area 31/32, Auxiliary Feedwater Pump Rooms, on August 15, 2007;
- Fire Area 80, Bus 121 Switchgear Room, on July 5, 2007;
- Fire Area 58, Unit 1 Auxiliary Building Elevation 695, on July 6, 2007;
- Fire Area 59, Unit 1 Auxiliary Building Elevation 715, on July 6, 2007;
- Fire Area 73, Unit 2 Auxiliary Building Elevation 695, on July 6, 2007;
- Fire Area 74, Unit 2 Auxiliary Building Elevation 715, on July 6, 2007;
- Fire Area 79, Train A Event Monitoring Room, on July 6, 2007;
- Fire Area 60, Unit 1 Auxiliary Building Elevation 735, on July 10, 2007; and
- Fire Area 75, Unit 2 Auxiliary Building Elevation 735, on July 10, 2007.
Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
1R06 Flood Protection Measures
Review of Operating Experience Smart Sample FY2007-02 Related to NRC Information Notice 2005-30 and Issues Associated with Conduit/Hydrostatic Seals
a. Inspection Scope
The inspectors reviewed licensee actions taken to address concerns described in NRC Information Notice 2005-30, and operating experience communication of the Kewaunee Turbine Building internal flooding issues. This inspection completed one internal flooding inspection sample.
The inspectors conducted a review of the details associated with the Kewaunee internal flooding issues and Turbine Building design to the Prairie Island plant design for similar internal flooding vulnerabilities. The inspectors reviewed the licensees corrective action program to verify that the licensee had entered and adequately evaluated the concerns identified at Kewaunee as part of their operating experience review process. The inspectors reviewed licensee procedures for the inspection and evaluation of flood seals, interviewed engineers responsible for internal flood protection, and conducted in-plant walkdown of internal flooding features with a specific focus on the penetration into the residual heat removal pump pits.
b. Findings
No findings of significance were identified.
1R07 Heat Sink Performance
Biennial Review of Heat Sink Performance
a. Inspection Scope
The inspectors reviewed the performance of the 121 safeguards control room chiller and the 22 diesel-driven cooling water pump jacket water heat exchanger which satisfied the requirement for two samples. These heat exchangers were chosen for review based on many factors, e.g., the high risk assessment worth in the licensees probabilistic risk analysis, the important safety-related mitigating system support functions and relatively low margin. This review resulted in the completion of two inspection samples. While on-site, the inspectors verified that the inspection, engineering, and maintenance activities were adequate to ensure proper heat transfer. This was done by conducting independent heat transfer capability calculations, reviewing the methods used to inspect the heat exchangers, verifying that the as-found results were appropriately dispositioned, and personnel interviews. The inspectors also verified, by review of procedures, test results, and interviews that chemical treatments, ultrasonic tests, and methods used to control biotic fouling corrosion and macro-fouling were sufficient to ensure required heat exchanger performance. The inspectors verified that the condition and operation of these heat exchangers were consistent with design assumptions in heat transfer calculations by reviewing related procedures and surveillance. This was performed by reviewing inspect/clean work orders, calculations, and completed surveillance tests. During the inspection, the inspectors walked down the accessible portions of the selected heat exchangers, and verified installation configurations complied with design documents and material condition was adequate.
Also while on-site, the inspectors verified two attributes of the ultimate heat sink as required by the NRC inspection procedure 71111.07B, Section 2.02, Items d.6 and d.7.
The inspectors verified that the licensee had appropriate controls in place to ensure functionality of the ultimate heat sink during adverse weather conditions, e.g., icing or high temperatures. The inspectors also verified that the licensee had appropriately completed recent performance testing for each of the three safety-related cooling water pumps. During the inspection, the inspectors walked down the screen house, focusing on the accessible portions of the safety-related intake bay, and cooling water pumps, and verified installation configurations complied with design documents and material condition was adequate.
The inspectors reviewed corrective action documents concerning heat exchanger or heat sink performance issues to verify that the licensee had an appropriate threshold for identifying issues. The inspectors also evaluated the effectiveness of the corrective actions for identified issues, including the engineering justifications for operability.
The documents that were reviewed are included in the Attachment to this report.
b. Findings
No findings of significance were identified.
1R11 Licensed Operator Requalification
a. Inspection Scope
On July 16, 2007, the inspectors performed a quarterly review of licensed operator requalification training in the simulator, completing one licensed operator requalification inspection sample. The inspectors observed a crew during an evaluated exercise in the plants simulator facility. The inspectors compared crew performance to licensee management expectations. The inspectors verified that the crew completed all of the critical tasks for each exercise scenario. For any weaknesses identified, the inspectors observed that the licensee evaluators noted the weaknesses and discussed them in the critique at the end of the session.
The inspectors assessed the licensees effectiveness in evaluating the requalification program ensuring that licensed individuals would operate the facility safely and within the conditions of their licenses, and evaluated licensed operator mastery of high-risk operator actions. The inspection activities included, but were not limited to, a review of high-risk activities, emergency plan performance, incorporation of lessons learned, clarity and formality of communications, task prioritization, timeliness of actions, alarm response actions, control board operations, procedural adequacy and implementation, supervisory oversight, group dynamics, interpretations of TS, simulator fidelity, and licensee critique of performance.
Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
1R12 Maintenance Effectiveness
a. Inspection Scope
The inspectors reviewed repetitive maintenance activities to assess maintenance effectiveness, including Maintenance Rule (10 CFR 50.65) activities, work practices, and common cause issues. The inspectors performed two issue/problem-oriented maintenance effectiveness samples under the Mitigating Systems and Barrier Integrity cornerstones. The inspectors assessed the licensees maintenance effectiveness associated with problems on:
- Recurring unavailability of cooling water system components; and
- Diesel generator D5 unavailability due to fuel rack position indication and elevated crankcase pressure.
The inspectors conducted in-office reviews of the licensees Maintenance Rule evaluations of equipment failures for maintenance preventable functional failures and equipment unavailability time calculations, comparing the licensees evaluation conclusions to applicable Maintenance Rule (a)(1) performance criteria. Additionally, the inspectors reviewed scoping, goal-setting (where applicable), performance monitoring, short-term and long-term corrective actions, functional failure definitions, and current equipment performance status.
The inspectors reviewed CAPs for significant equipment failures associated with risk-significant and safety-related mitigating equipment to ensure that those failures were properly identified, classified, and corrected. The inspectors reviewed other CAPs to assess the licensees problem identification threshold for degraded conditions, the appropriateness of specified corrective actions, and that the timeliness of the implementation of corrective actions was commensurate with the safety significance of the identified issues. Key documents used by the inspectors in conducting this inspection are listed in the Attachment to this report.
b. Findings
No findings of significance were identified.
1R13 Maintenance Risk Assessments and Emergent Work Control
a. Inspection Scope
The inspectors conducted in-plant walkdowns and in-office reviews of risk assessments for the following combinations of equipment unavailability completing five risk assessment and emergent work control inspection samples:
- Planned unavailability of the 121 instrument air compressor, the 121 instrument air receiver, and along with the emergent condition of the transmission system in a Yellow condition on July 25, 2007;
- Planned unavailability of the 12 motor-driven auxiliary feedwater pump, the 12 containment spray pump, and the 124 station air compressor on August 16, 2007;
- Planned unavailability of the 22 component cooling pump, the 22 component cooling heat exchanger, and the 124 station air compressor on September 4, 2007;
- Planned unavailability of the 12 component cooling pump, the 12 component cooling heat exchanger, and the 124 station air compressor on September 10, 2007;
- Planned unavailability of the 121 and 122 safeguards traveling screens, the 22 charging pump, and the 124 station air compressor, along with the emergent unavailability of the Byron 345kV [kiloVolt] transmission line and severe weather on September 18, 2007.
Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
1R15 Operability Evaluations
a. Inspection Scope
The inspectors reviewed the technical adequacy of six operability evaluations completing six operability evaluation inspection samples. The inspectors conducted these inspections by in-office review of associated documents and in-plant walkdowns of affected areas and plant equipment.
The inspectors compared degraded or nonconforming conditions of risk-significant structures, systems, or components associated with barrier and mitigating systems and against the functional requirements described in the TS, USAR, and other design basis documents; determined whether compensatory measures, if needed, were implemented; and determined whether the evaluation was consistent with the requirements of Administrative Work Instruction 5AWI 3.15.5, Operability Determinations. The following operability evaluations were reviewed by inspectors:
- Prompt operability of transformer CT 11 which had 7 of 18 cooling fans out of service on July 11, 2007;
- Operability Recommendation (OPR) 01109322, documenting the operability of the 11 and 21 reactor coolant pumps with seal parts installed without proper evaluation on September 4, 2007;
- Prompt operability of CAP 01099609, evaluating the impact of potential water hammer on line downstream of Unit 1 pressurizer power operated relief valves;
- Prompt operability of CAP 01104923, evaluating the D5 engine 1 dirty fuel oil tank level increase;
- OPR 01106141 that documents the historical operability of a failure of Breaker 26-9 to manually close during Surveillance Procedure (SP) 2090B on August 13, 2007; and
- OPR 01109516 documenting the operability of Safety Injection Pipe 3/4-2SI-7A with a missing pipe support on September 4, 2007.
Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
1R19 Post-Maintenance Testing
a. Inspection Scope
The inspectors assessed post-maintenance testing completing six post-maintenance test inspection samples. The inspectors selected post-maintenance tests associated with important mitigating, initiating events, and barrier integrity systems to ensure that the testing was performed adequately, demonstrated that the maintenance was successful, and that operability of associated equipment and/or systems was restored.
The inspectors conducted these inspections by in-office review of documents, in-plant walkdowns of associated plant equipment, and interviews with responsible personnel.
The inspectors observed and assessed the post-maintenance testing activities for the following maintenance activities:
- D5 diesel generator following troubleshooting for elevated crankcase pressure on July 17, 2007;
- Replacement of the 22 containment spray (CS) pump breaker following failure of breaker 26-9 to close during a surveillance test on August 9, 2007;
- 12 motor-driven auxiliary feedwater pump auxiliary lube oil pump following replacement of the timer relay on August 17, 2007;
- Control valve (CV)-31199, boric acid to 11 boric acid blender, following corrective maintenance on August 21, 2007;
- Refueling water storage tank to safety injection pumps valve MV-32183 following corrective maintenance on September 6, 2007; and
- CV-31411, component cooling water heat exchanger temperature control valve, following the execution of corrective and preventive maintenance activities on September 11, 2007.
The inspectors reviewed the appropriate sections of the TS, USAR, and maintenance documents to determine the systems safety functions and the scope of the maintenance. The inspectors also reviewed CAPs to verify that the licensee was identifying issues at an appropriate threshold and entering them into their corrective action program in accordance with the licensees corrective action procedures. Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
1R20 Refueling and Other Outage Activities
a. Inspection Scope
The inspectors observed the licensees performance during a planned Unit 2 maintenance outage (2F2402) conducted between September 29, 2007, and October 1, 2007. The purpose of the outage was to clean condenser tubes and balance the turbine generator. These inspection activities represent one outage inspection sample.
This inspection consisted of an in-office review of the licensees outage schedule, safe shutdown plan, and procedures governing the outage. Key documents used by the inspectors in conducting this inspection are listed in the Attachment to this report.
The inspectors conducted in-plant observations of the following outage activities daily:
- Attended outage management turnover meetings to verify that the current shutdown risk status was accurate, well understood, and adequately communicated; and
- Performed walkdowns of the main control room to observe the alignment of systems important to shutdown risk.
b. Findings
No findings of significance were identified.
1R22 Surveillance Testing
a. Inspection Scope
During this inspection period, the inspectors completed five surveillance inspection samples. Observation of SP 1088 and SP 1106B completed the quarterly inservice testing inspection sample requirement of a risk-significant pump or valve surveillance test. The observation of SP 2132 completed the requirement for a containment isolation sample. The inspectors selected the following surveillance testing activities as samples:
- SP 2307, D6 Diesel Generator 6-Month Fast Start Test, on July 2, 2007;
- SP 2132, Unit 2 Personnel and Maintenance Airlock Door Seal Test, on August 22, 2007;
- SP 1106B, 22 Diesel-Driven Cooling Water Pump Monthly Test, on August 12, 2007;
- D2 Diesel Generator 18-Month 24-Hour Load Test on July 9, 2007; and
- SP 1088A, Train A Safety Injection Quarterly Test, on July 26, 2007.
During completion of the inspection samples, the inspectors observed in-plant activities and reviewed procedures and associated records to verify, when applicable, that:
- Preconditioning did not occur;
- Effects of the testing had been adequately addressed by control room personnel or engineers prior to the commencement of the testing;
- Acceptance criteria were clearly stated, demonstrated operational readiness, and were consistent with the system design basis;
- Plant equipment calibration was correct, accurate, properly documented, and the calibration frequency was in accordance with TS, USAR, procedures, and applicable commitments;
- Measuring and test equipment calibration was current;
- Test equipment was used within the required range and accuracy;
- Applicable prerequisites described in the test procedures were satisfied;
- Test frequency met TS requirements to demonstrate operability and reliability;
- The tests were performed in accordance with the test procedures and other applicable procedures;
- Jumpers and lifted leads were controlled and restored where used;
- Test data/results were accurate, complete, and valid;
- Test equipment was removed after testing;
- Where applicable for inservice testing activities, testing was performed in accordance with the applicable version of American Society of Mechanical Engineers Code,Section XI, and reference values were consistent with the system design basis;
- Where applicable, test results not meeting acceptance criteria were addressed with an adequate operability evaluation or declared inoperable;
- Where applicable for safety-related instrument control surveillance tests, reference setting data have been accurately incorporated in the test procedure;
- Equipment was returned to a position or status required to support the performance of its safety functions; and
- All problems identified during the testing were appropriately documented in the corrective action program.
Key documents used by the inspectors in conducting this inspection are listed in the to this report.
b. Findings
No findings of significance were identified.
1R23 Temporary Plant Modifications
a. Inspection Scope
The inspectors conducted in-plant observations of the physical changes to the equipment and an in-office review of documentation associated with one temporary modification. This constituted one temporary modification inspection sample. The inspectors reviewed Temporary Modification EC 10362, which was implemented to remove parts from the manual valve actuator on CV-39412 (11 and 13 fan cooling unit chilled water return valve) to eliminate the possibility of the damaged threads on the hand wheel stem shaft interfering with the valves safety-related function to close.
The inspection activities included a review of design documents, safety screening documents, and the USAR to determine that the temporary modification was consistent with modification documents, drawings, and procedures. The inspectors also reviewed the post-installation test results to confirm that tests were satisfactory and the actual impact of the temporary modification on the permanent system and interfacing systems were adequately verified. The key documents reviewed by the inspectors are listed in the Attachment to this report.
b. Findings
No findings of significance were identified.
OTHER ACTIVITIES
4OA1 Performance Indicator Verification
Cornerstones: Mitigating Systems
Mitigating System Performance Index (MSPI) Verification of Emergency Alternating Current (EAC) Power Systems, High Pressure Safety Injection (HPSI), and Auxiliary Feedwater (AFW)
a. Inspection Scope
The inspectors reviewed the licensees MSPI unavailability and unreliability data, Consolidated Data Entry MSPI reports, monitored component demands, and demand failures, where applicable, for Prairie Island Units 1 and 2, EAC, HPSI, and AFW, completing six performance indicator verification inspection samples. The inspectors used performance indicator guidance and definitions contained in National Energy Institute Document 99-02, Regulatory Assessment Performance Indicator Guideline, Revision 4, to verify the accuracy of the performance indicator data. The inspectors review included conditions and data from control room narrative logs, control room limiting condition of operation (LCO) logs and calculations. The inspectors did not review MSPI risk coefficients since none had changed since the previous performed review.
The inspectors reviewed the CAPs listed in the Attachment to this report to verify that the licensee was identifying issues at an appropriate threshold and entering them into their corrective action program in accordance with corrective action procedures. Key documents used by the inspectors in conducting this inspection are listed in the to this report.
The licensees reporting of the following performance indicators were verified:
Unit 1
Unit 2
b. Findings
No findings of significance were identified.
4OA2 Identification and Resolution of Problems
.1 Routine Review of Identification and Resolution of Problems
a. Inspection Scope
As required by NRC Inspection Procedure 71152, Identification and Resolution of Problems, and in order to help identify repetitive equipment failures or specific human performance issues for follow-up, the inspectors performed screening of all items entered into the licensees corrective action program. This was accomplished by reviewing the description of each new CAP and attending selected daily management review committee meetings. Documents reviewed are listed in the Attachment to this report. This does not constitute an inspection sample.
b. Findings
No findings of significance were identified.
.2 Selected Issue Follow-up Inspection - Operator Workarounds
a. Inspection Scope
As required by NRC Inspection Procedure 71152, Identification and Resolution of Problems, the inspectors performed a review of the operator workarounds. This review verified that the licensee is identifying operator workaround problems at an appropriate threshold and entering them in the corrective action program, and has proposed or implemented appropriate corrective actions.
The issue selected for in-depth review was the three-way valves controlling bearing water sources for the safeguards cooling water pumps require operations to change out seal water filters once per shift. A bearing water supply modification was being implemented in three phases and was in progress with an estimated completion in September 2007.
This constitutes the completion of one inspection sample. The key documents reviewed by the inspectors associated with this inspection are listed in the Attachment to this report.
b. Findings and Observations
No findings of significance were identified.
4OA3 Event Follow-up
a. Inspection Scope
(Closed) Licensee Event Report (LER) 05000306/2007-001-01: Unit 2 Reactor Trip, Supplement 1.
On April 5, 2007, at approximately 9:08 a.m., Unit 2 tripped during surveillance testing of the Unit 2 train A safeguards logic. A spurious train A safety injection actuation occurred resulting in actuation of the reactor protection system and the reactor trip. The train was in Test at the time and should not have caused the reactor trip. The licensee entered the event into the corrective action program as CAP 01086219, replaced the defective Westinghouse MG-6 relay, and conducted a root cause evaluation of the event. The root cause was determined to be high electrical resistance on the relay contacts that did not allow enough current to reach the reset coil of the relay, resulting in failure of the relay to reset. It was further determined that the high electrical resistance was due to lack of developing and implementing a preventive maintenance program for MG-6 relays. Corrective actions planned include replacement and testing of the relays and implementation of a preventive maintenance strategy for the MG-6 relays. The LER supplement and root cause evaluation report were reviewed by the inspectors and no findings of significance were identified. This LER supplement is closed. The NRCs review of the original LER and disposition of the associated regulatory aspects were documented in NRC Inspection Report 05000306/2007003.
4OA6 Meeting(s)
.1 Exit Meeting
The inspectors presented the inspection results to Mr. M. Wadley and other members of licensee management at the conclusion of the inspection on October 4, 2007. The inspectors asked the licensee whether any materials examined during the inspection should be considered proprietary. No proprietary information was identified.
.2 Interim Exit Meeting
An interim exit meeting was conducted for:
- The results of the heat sink biennial inspection were presented to the Director of Site Operations, Mr. J. Sorensen, and other members of licensee management and staff at the conclusion of the inspection on June 29, 2007.
4OA7 Licensee-Identified Violations
The following three violations of very low significance were identified by the licensee and are violations of NRC requirements which meets the criteria of Section VI of the NRC Enforcement Manual, NUREG-1600, for being dispositioned as Non-Cited Violations.
Cornerstone: Initiating Events, Mitigating Systems, and Barrier Integrity
.1 Degraded Fire Barrier Between Auxiliary Feedwater Pump Rooms
On August 9, 2007, the licensee identified that a four-inch penetration between Fire Areas 31 and 32 was not intact due to the three-inch fire hose passing through the penetration. Fire Areas 31 and 32 contain all Unit 1 and 2 safety-related auxiliary feedwater pumps, instrument air compressors, and both Unit 1 and Unit 2 remote shutdown panels. The licensees investigation determined that this condition had existed for the previous ten years. During portions of that 10-year period, compensatory measures were not continuously in place. The Prairie Island Operating License Condition DPR-42 for Unit 1 and DPR-60 for Unit 2 required that the licensee maintain, in effect, all provisions of the approved fire protection program. The licensee failed to meet this requirement when the required compensatory measures per Plant Safety Procedure F5, Appendix K, Fire Protection Systems Operability Requirements, Revision 10, had not been maintained as required. A risk evaluation conducted by a Region III fire protection inspector and a senior risk analyst using the fire protection significance determination process, determined that the finding was of very low safety significance (Green) since no credible fire scenarios were identified that would damage important safe shutdown equipment in both areas. The licensee immediately restored the penetration integrity upon discovery and entered the deficient condition into their corrective action program with CAP 01106157.
.2 22 Containment Spray Pump Failed to Close During Surveillance Test Due to
Improperly Performed Maintenance On August 9, 2007, plant operators were performing a quarterly surveillance test of the 22 CS pump. Step 7.4.3 of SP 2090B directed operators to start the pump. When the control switch was taken to the start position, the safety-related 22 CS pump failed to start. The licensees troubleshooting revealed that open circuit condition existed in the breaker closing circuit. The licensee entered this deficient condition into their corrective action program with CAP 01106141 and conducted a root cause investigation of the event. The root cause investigation identified that the breakers L2 auxiliary contacts were not correctly adjusted during a major overhaul performed in May 2005. The root cause evaluation identified the improper assembly of the breaker linkage between the L2 auxiliary contacts and the breaker main contacts. Maintenance procedures were also identified as having insufficient guidance for successful completion of the maintenance activity. Appendix B, Criterion V, of 10 CFR 50 requires that procedures include appropriate qualitative or quantitative acceptance criteria for determining that important activities have been satisfactorily accomplished. Plant Maintenance Procedure PE 0008, 5HK250/350 Breaker Testing Maintenance and Repair - Major, Revision 3, contained neither appropriate qualitative or quantitative acceptance criteria, and therefore, failed to meet the regulatory requirements. The failure of the 22 CS pump did not result in a significant increase in either the core damage frequency or the large early release fraction. Therefore, the risk significance of this event was of very low safety significance (Green).
ATTACHMENT:
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee
- M. Wadley, Site Vice President
- T. Allen, Nuclear Safety Assurance Manager
- J. Anderson, Radiation Protection and Chemistry Manager
- M. Carlson, Engineering Director
- M. Davis, Regulatory Affairs Analyst
- K. Den Herder, GL 89-13 Program Owner
- F. Forrest, Operations Manager
- P. Gorman, Employee Concerns Manager
- P. Huffman, Plant Manager
- J. Kivi, Regulatory Compliance Engineer
- C. Mundt, General Supervisor, Instrument and Control Maintenance
- S. Northard, Regulatory Affairs Manager
- C. Sansome, former GL 89-13 Program Owner
- S. Skoyen, Engineering Project Manager
- J. Sorensen, Director Site Operations
- E. Weinkam, NMC Licensing Director
- P. Wiltse, Maintenance Manager
LIST OF ITEMS OPENED, CLOSED, AND DISCUSSED
Opened
- 05000306/2007-001-01 LER Unit 2 Reactor Trip, Supplement 1
Closed
- 05000306/2007-001-01 LER Unit 2 Reactor Trip, Supplement 1
Discussed
None.