IR 05000483/2016007
| ML16214A363 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 08/01/2016 |
| From: | Thomas Farnholtz Region 4 Engineering Branch 1 |
| To: | Diya F Union Electric Co |
| References | |
| IR 2016007 | |
| Download: ML16214A363 (19) | |
Text
UNITED STATES ust 1, 2016
SUBJECT:
CALLAWAY PLANT, UNIT 1- NRC EVALUATIONS OF CHANGES, TESTS, AND EXPERIMENTS AND PERMANENT PLANT MODIFICATIONS BASELINE INSPECTION REPORT 05000483/2016007
Dear Mr. Diya:
On June 30, 2016, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Callaway Plant, Unit 1. On June 30, 2016, the NRC inspectors discussed the results of this inspection with T. Hermann, Site Vice President, and other members of your staff.
Inspectors documented the results of this inspection in the enclosed inspection report.
The NRC inspectors did not identify any findings or violations of more than minor significance.
In accordance with Title 10 of the Code of Federal Regulations 2.390, Public Inspections, Exemptions, Requests for Withholding, of the NRC's "Rules of Practice and Procedure," a copy of this letter, its enclosure, and your response (if any) will be available electronically for public inspection in the NRCs Public Document Room or from the Publicly Available Records (PARS)
component of the NRC's 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/
Thomas R. Farnholtz, Chief Engineering Branch 1 Division of Reactor Safety Docket No. 50-483 License No. NPF-30
Enclosure:
Inspection Report 05000483/2016007 w/Attachment: Supplemental Information
REGION IV==
Docket(s): 50-483 License(s): NPF-30 Report(s): 05000483/2016007 Licensee: Union Electric Company Facility: Callaway Plant, Unit 1 Location: Junction Highway CC and Highway O Steedman, MO Dates: June 13 to June 30, 2016 Inspectors: G. George, Senior Reactor Inspector, Engineering Branch 1, Lead W. Smith, Reactor Inspector, Engineering Branch 1 J. Watkins, Reactor Inspector, Engineering Branch 2 Approved By: Thomas R. Farnholtz Chief, Engineering Branch 1 Division of Reactor Safety Enclosure
SUMMARY OF FINDINGS
IR 05000483; 06/13/2016 - 06/30/2016; Callaway Energy Center; Evaluations of Changes,
Tests, and Experiments and Permanent Plant Modifications.
This report covers a two-week announced baseline inspection on evaluations of changes, tests, and experiments and permanent plant modifications. The inspection was conducted by Region IV based engineering inspectors. No findings of more-than-minor significance were identified. The significance of most findings is indicated by their color (i.e., greater than Green, or Green, White, Yellow, Red) using Inspection Manual Chapter (IMC) 0609, Significance Determination Process (SDP). Cross-cutting aspects were determined using IMC 0310,
Aspects Within the Cross-Cutting Areas. Findings for which the SDP does not apply may be Green or be assigned a severity level after NRC management review. All violations of NRC requirements are dispositioned in accordance with the NRCs Enforcement Policy, dated July 9, 2013. The NRCs program for overseeing the safe operation of commercial nuclear power reactors is described in NUREG-1649, Reactor Oversight Process, Revision 5, dated February 2014.
NRC-Identified Findings
and Self-Revealed Findings No findings of more-than-minor significance were identified.
Licensee-Identified Violations
No findings of more-than-minor significance were identified.
REPORT DETAILS
REACTOR SAFETY
Cornerstones: Initiating Events, Mitigating Systems, Barrier Integrity, and Emergency Preparedness
1R17 Evaluations of Changes, Tests, and Experiments and Permanent Plant Modifications
.1 Evaluations of Changes, Tests, and Experiments
a. Inspection Scope
The inspectors reviewed 5 evaluations performed pursuant to Title 10, Code of Federal Regulations (CFR), Part 50, Section 59, to determine whether the evaluations were adequate and that prior NRC approval was obtained as appropriate. The inspectors also reviewed 25 screenings, where licensee personnel had determined that a 10 CFR 50.59 evaluation was not necessary. The inspectors reviewed these documents to determine if:
- the changes, tests, and experiments performed were evaluated in accordance with 10 CFR 50.59 and that sufficient documentation existed to confirm that a license amendment was not required;
- the safety issue requiring the change, tests and experiment was resolved;
- the licensee conclusions for evaluations of changes, tests, and experiments were correct and consistent with 10 CFR 50.59; and
- the design and licensing basis documentation was updated to reflect the change.
The inspectors used, in part, Nuclear Energy Institute (NEI) 96-07, Guidelines for 10 CFR 50.59 Implementation, Revision 1, to determine acceptability of the completed evaluations and screenings. The NEI document was endorsed by the NRC in Regulatory Guide 1.187, Guidance for Implementation of 10 CFR 50.59, Changes, Tests, and Experiments, dated November 2000. The list of evaluations, screenings, and/or applicability determinations reviewed by the inspectors is included as an attachment to this report.
This inspection constituted 5 samples of evaluations and 25 samples of screenings and/or applicability determinations as defined in Inspection Procedure (IP) 71111.17-04.
The minimum sample size for 10 CFR 50.59 evaluations was not met because the minimum number of evaluations since the previous triennial inspection were not available at the time of the inspection.
b. Findings
No findings were identified.
.2 Permanent Plant Modifications
a. Inspection Scope
The inspectors reviewed 11 permanent plant modifications that had been installed in the plant during the last three years. The modifications were selected based upon risk significance, safety significance, and complexity. The inspectors reviewed the modifications selected to determine if:
- the supporting design and licensing basis documentation was updated;
- the changes were in accordance with the specified design requirements;
- the procedures and training plans affected by the modification have been adequately updated;
- the test documentation as required by the applicable test programs has been updated; and
- post-modification testing adequately verified system operability and/or functionality.
The inspectors also used applicable industry standards to evaluate acceptability of the modifications. The list of modifications and other documents reviewed by the inspectors is included as an attachment to this report.
This inspection constituted 11 permanent plant modification samples as defined in Inspection Procedure 71111.17-04.
.2.1 Replacement of Safety-Related Current/Pneumatic Transducers
The inspectors reviewed Replacement Item Equivalency 14-0055, implemented to replace current/pneumatic transducers used to control position of safety-related atmospheric steam dump valves and turbine-drive auxiliary feedwater flow control valves. The previous Masoneilan current/pneumatic transducers were replaced with Thermo-Fisher Scientific current/pneumatic transducers. The Masoneilan transducers were highly susceptible to hysteresis and large magnitude drift. This engineering replacement involved the seismic qualification and testing of the Thermo-Fisher Scientific transducer. The replacement item equivalency also modified existing instrumentation tubing associated with the replacement transducers. The inspectors did not identify any more-than-minor concerns with the design change package.
.2.2 Commercial Grade Replacement of Diesel Crankcase Pressure Switch
The inspectors reviewed Commercial Grade Dedication 0422-1, implemented to replace obsolete United Electric J300-440 pressure switches with United Electric J400-440 pressure switches. The licensee completed a commercial grade dedication evaluation to evaluate the critical characteristics associated with the safety functions of the pressure switches to maintain crankcase pressure boundary and maintain continuity of the safety-related circuit. The inspectors reviewed the critical characteristic evaluation and operational tests of the new pressure switches. The inspectors did not identify any concerns with the design change package.
.2.3 Modification to Seismically Analyze Fire Protection Pipe in the Fuel Building
The inspectors reviewed Replacement Item Equivalency 15-001, implemented to seismically analyze existing fire protection pipe in the fuel building and determine if additional seismic supports were necessary. The licensee had identified, in Callaway Action Request 201405221, that a section of the fire protection pipe in the fuel building was not seismically supported as reflected in drawings; therefore, the assumed pipe break in an internal flooding calculation was potentially non-conservative. To correct the condition, the licensee seismically analyzed the unsupported sections fire protection piping in accordance with ASME Boiler and Pressure Vessel Code Section III, 1974 Edition, 1975 Summer Addenda, piping design criteria. The inspectors did not identify any concerns with the design change package.
.2.4 Revise Overcurrent Protection in the Containment Penetrations for Motor Operated
Valves The inspectors reviewed Modification Package 15-009, implemented to install additional cabling for motor operated valves going through containment electrical penetration assemblies for component cooling water containment isolation valve EGHV0062 and EJHV8811A, and containment recirculation sump isolation valves EJHV8811BA and EJHV8811B. This modification was necessary to ensure that the instantaneous breaker settings associated with these valves would protect the electrical penetration conductors throughout the entire penetration time-current damage curve. This modification revised the wiring going through the containment penetration by adding an additional power conductor to increase the ampacity of the associated circuits. Additionally, the upper trip tolerance acceptance criteria for the associated breakers were changed and the breakers were retested within the new tolerances. The inspectors did not identify any concerns with the design change package.
.2.5 Hardened Condensate Storage Tank
The inspectors reviewed Modification Package 13-0033 which installed a hardened condensate storage tank to meet NRC Order EA-12-049. The NRC order was issued for beyond design basis external events, and required licensees to use a condensate storage tank as the first alternative to normal and makeup water sources. The existing condensate storage tank was not sufficiently protected from external events, so a hardened condensate storage tank was added and tied into the auxiliary feedwater system. The inspectors reviewed the connections to the safety-related auxiliary feedwater system and the construction and operation of the tank. Specifically, the inspectors reviewed the isolation valves, check valves, level setpoints for swapover logic, the nitrogen sparge system, and any affects to the net positive suction head for the safety-related pumps. The inspectors did not identify any concerns with the design change package.
.2.6 Replacement Component Cooling Water Pump Oil Bearings and Oil Sight Glasses
The inspectors reviewed Modification Package 04-1021 which installed new pump bearing covers to prevent oil leakage from the shaft of the pumps and to install oil sight glasses that provided better indication of oil level on component cooling water pumps PEG01A, PEG01B, PEG01C, and PEG01D. The existing bearing seals on the component cooling water pumps allowed oil leakage through the bearing housing, which would challenge the operability of the system. Additionally, the constant level oilers were repositioned with oil level sight glasses so that the oil level in component cooling water pumps could be determined by operators. The inspectors did not identify any concerns with the design change package.
.2.7 Replacement Drain Valves on Control Room and Class 1E Air Conditioning Units
The inspectors reviewed Modification Package 13-0005 that replaced the oil drain plugs with valves for the control room air conditioning units SGK04A and SGK04B and Class 1E air conditioning units SGK05A and SGK05B. The control room air conditioning unit SGK04B was replaced in March 2013 and the licensee discovered that the replacement unit had an oil drain valve instead of an oil drain plug as specified by the design documentation. For improved maintenance purposes, the licensee changed the design of the oil drain plugs to allow for oil drain valves on SGK04A, SGK04A, SGK05A, and SGK05B. The addition of an oil drain valve allowed for maintenance to be performed without draining the entire oil reservoir and also shortened the maintenance duration because the valve did not require a wait time for the thread sealant chemicals on the fitted connection to the drain to cure. The inspectors did not identify any concerns with the design change package.
.2.8 Isolate Containment Air Cooler Coil
The inspectors reviewed Modification Package 08-0055, implemented to isolate the supply and return lines for train B containment cooler coil SGN01BR3. Specifically, the modification installed blind flanges to isolate essential service water flow to and from containment cooler coil tube bundle SGN01BR3, located on the right bank and third from the top of the containment air cooler SGB01B. Cooler coil SGN01BR3 was isolated because of excessive leakage in the tube bundles, and was replaced with a new bundle and put back into service in a subsequent refueling outage. During the period with the cooler coil tube bundle out of service, the heat removal capacity of the containment coolers was diminished, but adequate to perform its safety function. The inspectors did not identify any concerns with the design change package.
.2.9 Evaluate Lower Amperage Fuses for Various 14 AWG Control Circuits in Main Control
Room The inspectors reviewed Modification Package 05-3029, implemented to evaluate inadequately protected cables which are in circuits from multiple fire areas which culminate into main control room. This modification would eliminate the possibility of secondary fires as described in Sections B3.3 and B3.4 of NFPA 805. Each circuit was investigated to determine if the current fuse rating adequately protected the associated control cable conductors. Evaluated fuses that did not provide adequate protection of the conductors were replaced with lower amperage fuses that do provide the necessary cable protection without interfering with the normal operation of the equipment. Where circuits were found that the fuse rating could not be reduced, additional fuse blocks and lower rated fuses were installed for the specific affected cables. The inspectors reviewed the calculations, a sample of the affected circuits wiring diagrams and schematics for the new fuses to verify the installation met the requirements of the modification and was in accordance with the design. The inspectors did not identify any concerns with the design change package.
.2.10 Main Transformer Replacement
The inspectors reviewed Modification Package 09-0074, implemented to replace the four main generator step-up transformers. Three in-service transformers, one per phase, and one spare transformer were replaced along with all associated controls, cooling, and monitoring equipment. The transformers were replaced due to the existing transformers reaching their end of life as evidenced by increasing levels of combustible gases being produced by the transformers. A bushing monitoring and an online 8-gas dissolved gas analyzer system were installed on the new transformers to improve monitoring of the generator step-up transformers. In addition, the existing fire deluge system was replaced with a perimeter-style (horseshoe shaped) system. This was modified to reduce the probability of the fire protection piping surrounding the transformers from damage, in the event of a catastrophic transformer failure. Existing oil containment structures were evaluated to ensure that the additional oil could still be contained. The concrete support structure for the spare transformer was modified to accommodate the additional weight of the new transformers. The inspectors reviewed the procurement specifications, removal and installation instructions, and walked down the installation of the new transformers and new horse-shoe-shaped deluge fire protection system to verify the installation met the requirements of the modification and was in accordance with the design. The inspectors did not identify any concerns with the design change package.
.2.11 Replace the Ametek Iso-Limiter Transformers XPN07 & XPN08
The inspectors reviewed Modification Package 09-0051, implemented to replace the existing ferroresonant transformers that normally supply power to non-safety instrument alternating current busses PN07 and PN08. The existing transformers generated large amounts of heat which caused frequent failures and made them prone to catch fire. The transformers created vibrations which contributed to the failures of the equipment. As a result of these reliability issues, these transformers required frequent replacement and have been replaced nearly 30 times over the life of the plant. These transformers have been replaced with improved design models, which consists of a single three-phase transformer with a different core material that does not generate the excessive heat and noise. The inspectors reviewed the wiring diagrams and schematics for the new transformers, walked down the installation of the new transformers, verified the post modification noise and heat levels of the replaced transformers, and verified the installation was in accordance with the design. The inspectors did not identify any concerns with the design change package.
b. Findings
No findings were identified.
OTHER ACTIVITIES
4OA2 Problem Identification and Resolution
.1 Review of Corrective Action Program Documents
a. Inspection Scope
The inspectors reviewed five corrective action program documents that identified or were related to 10 CFR 50.59 program and permanent plant modifications. The inspectors reviewed these documents to evaluate the effectiveness of corrective actions related to permanent plant modifications and evaluations of changes, tests, and experiments. In addition, corrective action documents written on issues identified during the inspection were reviewed to verify adequate problem identification and incorporation of the problems into the corrective action system. The list of specific corrective action documents that were sampled and reviewed by the inspectors are listed in the attachment to this report.
b. Findings
No findings were identified.
4OA6 Meetings
.1 Exit Meeting Summary
On June 30, 2016, the inspectors presented the preliminary inspection results to Mr. T. Herrmann, Site Vice President, and other members of the licensees staff. The licensee acknowledged the results as presented. No proprietary information was reviewed during this inspection or included in this report.
SUPPLEMENTAL INFORMATION
KEY POINTS OF CONTACT
Licensee Personnel
- S. Abel, Director, Engineering Projects
- J. Bruemmer, System Engineer, Engineering Programs
- C. Cash, Design Engineer, Engineering Design
- S. Chou, Design Engineer, Engineering Design
- M. Covey, Operations Manager, Operations
- T. Herrmann, Site Vice President
- L. Eitel, Supervisor, Engineering Design
- T. Elwood, Supervising Engineer, Regulatory Affairs and Licensing
- D. Epperson, Supervising Engineer, Engineering Design
- M. Haag, Principal Design Engineer, Engineering Design
- D. Hecker, System Engineer, Engineering Programs
- B. Jungmann, Director, Maintenance
- S. Kovaleski, Director, Engineering Design
- S. McLaughlin, Manager, Performance Improvement
- K. Mills, Director, Engineering Programs
- K. Norman, Design Engineer, Engineering Design
- E. Olson, Director, Engineering Programs
- S. Petze, Engineer, Regulatory Affairs
- G. Sellmayer, Supervising Engineer, Engineering Design
- P. Shirgur, Design Engineer, Engineering Design
- E. Smith, Supervisor, Nuclear Oversight Services
- S. Taylor, Design Engineer, Engineering Design
- D. Waller, Supervising Engineer, Major Projects
NRC Personnel
T. Hartman - Senior Resident Inspector
M. Langelier - Resident Inspector
LIST OF ITEMS OPENED, CLOSED, DISCUSSED, AND UPDATED
None