IR 05000289/2013007
ML13233A228 | |
Person / Time | |
---|---|
Site: | Three Mile Island ![]() |
Issue date: | 08/20/2013 |
From: | Paul Krohn Engineering Region 1 Branch 2 |
To: | Pacilio M Exelon Generation Co, Exelon Nuclear |
Krohn P | |
References | |
IR-13-007 | |
Download: ML13233A228 (21) | |
Text
UNITED STATES ust 20, 2013
SUBJECT:
THREE MILE ISLAND STATION - NRC EVALUATION OF CHANGES, TESTS, OR EXPERIMENTS AND PERMANENT PLANT MODIFICATIONS TEAM INSPECTION REPORT 05000289/2013007
Dear Mr. Pacilio:
On July 12, 2013, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Three Mile Island, Unit 1 (TMI) facility. The enclosed inspection report documents the inspection results, which were discussed on July 12, 2013, with Mr. Mark Newcomer, TMI Plant Manager, and other members of your staff.
The inspection examined activities conducted under your license as they relate to safety and compliance with the Commissions rules and regulations and with the conditions of your license.
In conducting the inspection, the team reviewed selected procedures, calculations and records, observed activities, and interviewed station personnel.
Based on the results of this inspection, no findings were identified.
In accordance with 10 CFR 2.390 of the NRC's "Rules of Practice," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of the NRC's document system, Agencywide Documents Access and Management System (ADAMS).
ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).
Sincerely,
/RA/
Paul G. Krohn, Chief Engineering Branch 2 Division of Reactor Safety Docket No: 50-289 License No: DPR-50
M.
Enclosure:
Inspection Report 05000289/2013007 w/ Attachment: Supplemental Information
REGION I==
Docket No.: 50-289 License No.: DPR-50 Report No.: 05000289/2013007 Licensee: Exelon Facility: Three Mile Island Nuclear Power Plant Location: Middletown, PA Inspection Period: June 24 through July 12, 2013 Inspectors: David Kern Senior Reactor Inspector Division of Reactor Safety (DRS)
Team Leader Stephen Pindale Senior Reactor Inspector, DRS Richard Montgomery Project Engineer, DRP Approved By: Paul Krohn, Chief Engineering Branch 2 Division of Reactor Safety i Enclosure
SUMMARY OF FINDINGS
IR 05000289/2013007; 6/24/2013-7/12/1013; Three Mile Island Nuclear Power Plant (TMI);
Evaluation of Changes, Tests or Experiments, and Permanent Plant Modifications.
This report covers a two week on-site inspection period of the evaluations of changes, tests, or experiments and permanent plant modifications. The inspection was conducted by two region based engineering inspectors and one region based reactor projects inspector. No findings were identified. 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.
ii
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, and Barrier Integrity
1R17 Evaluations of Changes, Tests, or Experiments and Permanent Plant Modifications
.1 Evaluations of Changes, Tests, or Experiments (25 samples)
a. Inspection Scope
The team reviewed five safety evaluations to determine whether the changes to the facility or procedures, as described in the Updated Final Safety Analysis Report (UFSAR), had been reviewed and documented in accordance Title 10 of the Code of Federal Regulations (10 CFR) 50.59 requirements. In addition, the team evaluated whether Exelon had been required to obtain U.S. Nuclear Regulatory Commission (NRC) approval prior to implementing the changes. The team interviewed plant staff and reviewed supporting information including calculations, analyses, design change documentation, procedures, the UFSAR, Technical Specifications (TS), and plant drawings to assess the adequacy of the safety evaluations. The team compared the safety evaluations and supporting documents to the guidance and methods provided in Nuclear Energy Institute (NEI) 96-07, Guidelines for 10 CFR 50.59 Evaluations, Revision 1, as endorsed by NRC Regulatory Guide 1.187, Guidance for Implementation of 10 CFR 50.59, Changes, Tests, and Experiments, to determine the adequacy of the safety evaluations.
The team also reviewed a sample of twenty 10 CFR 50.59 screenings, applicability reviews, item equivalency changes, commercial change packages, equivalency change packages, temporary configuration change packages, and commercial grade dedications for which Exelon had concluded that a safety evaluation was not required. These reviews were performed to assess whether Exelon's threshold for performing safety evaluations was consistent with 10 CFR 50.59. The sample included design changes, calculations, and procedure changes.
The team reviewed the safety evaluations and screenings that Exelon had performed and approved during the time period covered by this inspection that had not been previously reviewed by NRC inspectors. All safety evaluations since the last modifications inspection were reviewed, and the screenings and applicability determinations selected were based on the safety significance, risk significance, and complexity of the change to the facility.
In addition, the team compared Exelons administrative procedures used to control the screening, preparation, review, and approval of safety evaluations to the guidance in NEI 96-07 to determine whether the procedures adequately implemented the requirements of 10 CFR 50.59. The reviewed safety evaluations and screenings are listed in the Attachment.
b. Findings
No findings were identified.
.2 Permanent Plant Modifications (12 samples)
.2.1 Equivalent Pressure Switch for FW-PS-29A
a. Inspection Scope
The team reviewed equivalent change TM 11-00571-000, which modified the alarm function of components connected to the output of the 1A feedwater pump governor oil pressure switch (PS29A). This pressure switch had been recently replaced; however, Exelon discovered that certain switch contacts opened instead of closing upon decreasing governor oil pressure. As a result, annunciator M-2-2 and a computer point did not respond as expected to governor oil pressure signals. This modification changed annunciator M-2-2 and computer point S2045 to alarm on decreasing oil pressure when PS29A output contacts opened instead of when they closed. The redundant features associated with PS29B still alarmed on decreasing oil pressure and therefore that pressure switch was not changed.
The team reviewed the modification to verify that the design and licensing bases had not been degraded by the reversed contacts. The team interviewed the responsible engineer and reviewed associated evaluations to verify that the modified configuration was consistent with existing design assumptions. The team reviewed the associated procedures and drawings to ensure the necessary changes were implemented. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the
.
b. Findings
No findings were identified.
.2.2 Alternate Once-Through Steam Generator Tube Stabilizer
a. Inspection Scope
The team reviewed equivalent change TM 11-00543-000, which permitted the use of a standard full-length stabilizer for specific tube locations in the once-through steam generators (OTSG), as opposed to the hybrid design stabilizer. The purpose of tube stabilizers is to maintain the structural integrity of a tube that has shown indications via eddy current testing, such that in the presence of flow-induced vibration the tube does not completely sever. The hybrid design incorporated a solid alloy rod along the length of the assembly in combination with strand wire rope cables, and was designed for installation along the periphery of the OTSG grid and for tubes with indications in the top span of the tube. Due to installation interference issues, this modification evaluated the use of the standard full-length stabilizer. The 30 degraded tubes affected by this modification did not have indications in the top span of the tubes. The associated analysis accepted the use of this stabilizer for two operating cycles. The team reviewed the modification to verify that the design and licensing bases had not been degraded by the use of the alternate OTSG tube stabilizer. The team interviewed the responsible engineers and reviewed the associated evaluations to verify that the modified configuration was consistent with existing design assumptions. A sample of post-installation tests of the OTSG tube stabilizers was reviewed to verify the integrity of the installed components. Also, the team reviewed Exelons current plans to initiate actions to further assess the alternate configuration beyond the two operating cycles permitted by this modification. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.3 MU-V-16A/B Multiple Spurious Operation Modification
a. Inspection Scope
The team reviewed modification TM 12-00331-000, which modified make-up system valves MU-V-16A and MU-V-16B to address a specific multiple spurious operation (MSO) scenario, MSO Scenario 53 (spurious motor-operated valve operation, and wire-to-wire short(s) bypass torque and limit switches). Previously, only the open function for these valves was addressed for this scenario. This modification implemented a similar circuitry modification to provide defense-in-depth to protect the valves while being closed for the same postulated scenario. Specifically, the valves torque and limit switches were electrically repositioned to the ground side of their respective close contactor coils, and sleeving was applied to jumpers within the valve motor control center buckets to add protection for a postulated localized motor control center fire.
The team reviewed the modification to verify that the design and licensing bases had not been degraded by repositioning the torque and limit switches. The team interviewed the responsible engineer and reviewed associated evaluations to verify that the modified configuration was consistent with existing design assumptions and regulatory requirements. Operation and design of similar valves to evaluate whether the valves were the team also reviewed the appropriately protected for the same MSO scenario.
Drawings were reviewed to verify that the necessary updates were implemented, and post-modification testing was reviewed to verify that the testing confirmed acceptable valve operation. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.4 Engineered Safeguards Actuation System Alternating Current (AC) Relay Replacement
a. Inspection Scope
The team reviewed modification TM 12-00471-002, which was designed to replace the engineered safeguards actuation system (ESAS) relays. The existing relays were problematic (e.g., armature misalignment, abnormal buzzing, high resistance contacts)and are expected to be discontinued. The project scope for this modification included replacement of 238 relays. At the time of this inspection, one upgraded ESAS relay had been installed, which was implemented via modification TM 12-00534. Each relay or relay group will be implemented via a separate modification number, which is a sub-modification to parent modification TM 12-00471-002.
The team reviewed the modification to verify that the design and licensing bases had not been degraded by the relay replacement modification. The team interviewed the responsible engineer and reviewed associated evaluations to verify that the modified configuration and relay operating characteristics were consistent with design assumptions. The team conducted a walkdown to observe a mockup relay installation that was performed prior to implementing the work package, as well as a walkdown of the installed replacement relay in ESAS Cabinet 4A. Drawings requiring revision due to the modification were reviewed to verify appropriate changes were made, and post-modification test results were reviewed to verify that the testing confirmed acceptable relay installation and operation. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.5 Issue Nuclear Service Pump In-Service Testing Flow Accuracy Calculation
a. Inspection Scope
The team reviewed equivalent change TM 11-00031 that issued calculation C-1101-541-E420-037. TMI implemented this modification to evaluate the Nuclear Service Closed Cycle Cooling Water pump in-service testing quarterly flow accuracy and to prove that the flow accuracy satisfied the American Society of Mechanical Engineers (ASME) Operations and Maintenance (OM) code requirement of two percent of full scale. While the design basis was changed, no physical plant changes were made by this modification.
The team reviewed the calculation to verify that the design bases, licensing bases, and performance capability of the Nuclear Service pumps (NS-P-1A/B/C) had not been degraded by the modification. The team interviewed design engineers and reviewed associated calculations, evaluations, and issue reports to verify that the modification adequately determined that the current design was capable of meeting the ASME OM code requirements for flow measurement accuracy. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section
1R17 .1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.6 Replacement Valve for DF-V-23A/B
a. Inspection Scope
The team reviewed Item Equivalency Change (IEC) TM 11-00085, which permitted, the replacement of the currently installed and obsolete single poppet diesel fuel oil tank foot valve (Dover OPW Part Number 85) with the manufacturers new recommended double poppet foot valve (Dover OPW Part Number 86-0033). The double poppet design provided redundancy for holding the prime in the system and was recommended for installation in applications where the valve is not easily accessible.
The team reviewed the modification to verify that the design bases, licensing bases, and performance capability of the diesel fuel oil tank foot valves would not be degraded by the modification. The team interviewed design engineers and reviewed associated calculations, evaluations, drawings, and issue reports to verify that the modified configuration was consistent with existing design assumptions. The team also reviewed IEC TM 09-00689, which was superseded by this IEC to ensure that a complete re-evaluation was performed. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.7 Diesel Generator Ventilation Calculation Revision
a. Inspection Scope
The team reviewed equivalent change TM 12-00005, which involved a revision to the Emergency Diesel Generator (EDG) ventilation calculation (C-1101-831-5360-002).
Revision 0 of this calculation incorrectly assumed that EDG room fans AH-E-29A/B needed to be manually restarted after a Loss of Offsite Power (LOOP). The calculation assumed it would take an operator 20 minutes to manually restart the fans. However, fans AH-E-29A/B run continuously during normal operation and start automatically upon an EDG start following a LOOP. No manual operator action was necessary to start these fans. Therefore, the scope of this calculation revision was to remove the 20 minute manual operator requirements to start the fans. While the design basis of the fans was changed, no physical plant changes were made by this modification. The team reviewed the calculation to verify that the design bases, licensing bases, and performance capability of the EDG fans AH-E-29A/B had not been degraded by the modification. The team interviewed design engineers and reviewed associated calculations, evaluations, drawings, procedures, and issue reports to verify the modification was consistent with existing design assumptions. Additionally, the team walked down the control room to verify that the fans where running and that operators where familiar with the fans continuous mode of operation. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.8 Security Improvements
a. Inspection Scope
The team reviewed commercial change TM 10-00114, for advance work associated with a security improvements project to verify that the design bases, licensing bases, and performance capability of the plant had not been degraded by the modification. The team interviewed the responsible engineer, Site Operations Security Manager, and Station Fire Marshal and reviewed associated calculations, evaluations, drawings, work orders, and procedures to verify that the modifications were appropriately implemented and would function in accordance with the design assumptions. Additionally, the team walked down the accessible portions of the multiple modifications to ensure they were installed in accordance with the design instructions. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section
1R17 .1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.9 Recent Security Upgrades
a. Inspection Scope
The team reviewed commercial change TM 12-00210, for advance work associated with the recent security upgrades to verify that the design bases, licensing bases, and performance capability of the plant had not been degraded by the modification. The team interviewed the responsible engineer and Site Operations Security Manager, as well as reviewed associated evaluations, drawings, work orders, and procedures to verify that the modifications were appropriately implemented and would function in accordance with the design assumptions. Additionally, the team walked down the accessible portions of the multiple modifications to ensure they were installed in accordance with the design instructions. The 10 CFR 50.59 screening determination associated with this modification was reviewed as described in section 1R17.1 of this report. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.10 12-00395, Fire Hazards Analysis Report Change for Letdown Manual Actions,
Revision 0
a. Inspection Scope
The team reviewed modification TM 12-00395, which removed manual operator actions for reactor coolant system letdown restoration from the Fire Hazards Analysis Report (FHAR) for certain fire zones/areas. Letdown restoration is required for Fire Safe Shutdown when reactor coolant pump seal cooling has been maintained and one of the following conditions is met in a fire zone/area: 1) High pressure injection cooling is credited for decay heat removal in the fire zone/area or 2) Both pressurizer heater groups are subject to unavailability in the fire zone/area. Engineers had determined that several of the station fire zones/areas for which letdown restoration was credited in the FHAR, did not meet either of the two conditions specified above. Accordingly engineers removed letdown restoration requirements from the FHAR for those identified fire zones/areas.
The team reviewed the modification to verify that the design and licensing bases for postulated 10 CFR Part 50, Appendix R events had not been degraded by the modification. The team interviewed engineering staff and reviewed the FHAR, selected procedures, and drawings to confirm the details and assumptions in the modification.
The team reviewed the revised FHAR to ensure it was properly updated for the fire zones/areas which did not require manual operator actions for letdown restoration. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.11 Commercial Grade Dedication of One Time UL Class K5 General Purpose Fuse
250 Volts
a. Inspection Scope
The team reviewed commercial grade dedication (CGD) TI-92-0013, which certified commercially procured 6 amp fuses for use in safety related applications. The CGD technical evaluation identified six critical characteristics to be verified for acceptance of the fuses. A 10 CFR Part 50, Appendix B certified facility was contracted to perform testing and evaluation to verify the fuses met the specified critical characteristics.
Procurement engineers reviewed the test results and implemented this CGD on April 22, 2010 to certify eight fuses. Material inventory records indicated six of the eight fuses were subsequently issued for use and two remained in stock. Three of the fuses were issued under work order R2153711, EDG 1B Generator (EG-Y-1B) relay cabinet inspection and cleaning, performed on June 14, 2011.
The team reviewed the modification to verify that the design bases, licensing bases and performance capability of the EDG had not been degraded by the modification. The team interviewed procurement engineering staff and reviewed technical evaluations, industry test standards, and test results associated with the CGD to determine if the EDG and its support systems would function in accordance with design assumptions (Issue Report (IR) 1534891). The team reviewed the associated work order to verify that maintenance personnel implemented the modification as designed. The team reviewed the associated post-modification test results and performed a field verification of the fuse installation in the EG-Y-1B relay cabinet to verify the fuses were properly installed and no abnormal visual characteristics were present. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
.2.12 Joslyn Clark XKPM-10 Magnet and Rod Relay Kit
a. Inspection Scope
The team reviewed commercial grade dedication 09-00772, which certified commercially procured magnet and rod relay kits for use in safety related applications. The CGD technical evaluation identified nine critical characteristics to be verified for acceptance of the relay kits. The critical characteristics and acceptance criteria were developed based on TMI site operating experience, troubleshooting, corrective action program evaluations of failed relays, and a consultation with the manufacturer. All verification of critical characteristics for the group of 20 relay kits was performed by TMI staff. Material inventory records indicated one of these relay kits was issued for installation in ESAS cabinet 4B.
The team reviewed the modification to verify that the design bases, licensing bases and performance capability of the ESAS had not been degraded by the modification. The team interviewed procurement engineering staff and reviewed technical evaluations, industry test standards, and test results associated with the CGD evaluate whether the ESAS and its support systems would function in accordance with design assumptions.
The team reviewed the associated work order to verify that maintenance personnel implemented the modification as designed. The team reviewed the associated post-modification test results and performed a field verification of the relay kit installation in ESAS cabinet 4B to verify the relay kit was properly installed and no abnormal visual characteristics were present. The documents reviewed are listed in the Attachment.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA2 Identification and Resolution of Problems (IP 71152)
a. Inspection Scope
The team reviewed a sample of issue reports associated with 10 CFR 50.59 and plant modification issues to evaluate whether Exelon was appropriately identifying, characterizing, and correcting problems associated with these areas, and whether the planned and/or completed corrective actions were appropriate. In addition, the team reviewed IRs written on issues identified during the inspection to verify adequate problem identification and incorporation of the problem into the corrective action system.
The IRs reviewed are listed in the Attachment.
b. Findings
No findings were identified.
4OA6 Meetings, including Exit
The team presented the inspection results to Mr. M. Newcomer, Plant Manager, and other members of Exelon's staff at an exit meeting on July 12, 2013. The team returned the proprietary information reviewed during the inspection and verified that this report does not contain proprietary information.
ATTACHMENT
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Exelon Personnel
C. Armer System Engineer
- D. Atherholt Manager, Regulatory Assurance
D. Auch Mechanical Design Engineer
- P. Bennett Manager, Mechanical Design Engineering
S. Diven System Engineer
S. Dunkelberger Mechanical Design Engineer
- J. Dullinger Director, Site Engineering
R. Ezzo Electrical Design Engineer
M. Fitzwater Senior Regulatory Assurance Engineer
D. Hull Mechanical Design Engineer
K. Hurstic Mechanical Design Engineer
D. McGettrick Lead Design Engineer
F. McGuire Mechanical Design Engineer
W. McSorley Flood Protection Engineer
M. Mullens Mechanical Design Engineer
M Newcomer Plant Manager
- J. Piazza Senior Manager, Design Engineering
J. Sherk Mechanical Design Engineer
P. Sier Electrical Design Engineer
- B. Stein Supervisor, Procurement and Procurement Engineering
W. Stanley Reactor Engineer
K. Tremblay Senior Procurement Engineer
NRC
- D. Werkheiser NRC, Senior Resident Inspector
- J. Heinly NRC, Resident Inspector
LIST OF ITEMS
OPENED, CLOSED AND DISCUSSED
None