ML17171A233

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Response to Request for FLEX Audit Documentation
ML17171A233
Person / Time
Site: Wolf Creek Wolf Creek Nuclear Operating Corporation icon.png
Issue date: 06/12/2017
From: Hafenstine C
Wolf Creek
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
RA 17-0067
Download: ML17171A233 (32)
v • d • e


Text

Cynthia R. Hafenstine Manager Nuclear and Regulatory Affairs June 12, 2017 RA 17-0067 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555

References:

1) Letter dated March 12, 2012, from E. J. Leeds and M. R. Johnson, USNRC, to M. W. Sunseri, WCNOC, "Issuance of Order to Modify

. Licenses with Regard to Requirements for Reliable Spent Fuel Pool Instrumentation"

2) NRC Interim Staff Guidance JLD-ISG-2012-03, Compliance with Order EA-12-051, "Reliable Spent Fuel Pool Instrumentation,"

Revision 0, dated August 29, 2012

3) Letter dated March 26, 2014, from J. R. Davis, USNRC, to A. C.

Heflin, WCNOC, "Nuclear Regulatory Commission Audits of Licensee Responses to Reliable Spent Fuel Pool Instrumentation Order EA-12-051"

Subject:

Docket No. 50-482: Response to Request for FLEX Audit Documentation To Whom It May Concern:

On March 12, 2012, the Nuclear Regulatory Commission (NRC) issued Order EA-12-051 (Reference 1) to Wolf Creek Nuclear Operating Corporation (WC NOC). Reference 1 was to be made immediately effective and directed WCNOC to have a reliable indication of the water level in associated spent fuel storage pools. Specific requirements are outlined in Attachment 2 of Reference 1.

The NRC issued WCNOC Interim Staff Evaluation (ISE) and Request for Additional Information (RAI) regarding the Overall Integrated Plan for implementation of Order EA-12-051 in Reference 2. Reference 3 described the Order EA-12-051 audit process and plan, and requested sites participating in the audit process not to formally submit their RAI responses on the docket but instead, put their responses and any other supporting information on the licensee's ePortal. Per the request of NRC Project Manager, Peter Bamford, the Enclosures to this letter provide responses to NRC questions provided on the ePortal in support of the Wolf Creek Generating Station FLEX audit.

P.O. Box 411 I Burlington, KS 66839 / Phone: (620) 364-8831 An Equal Opportunity Employer M/F/HCNET

RA 17-0067 Page 2 of 2 This letter contains no commitments. If you have any questions concerning this matter, please contact me at (620) 364-4204.

Sincerely, Cynthia R. Hafenstine CRH/rlt

Enclosures:

NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 2-F II NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 3-F Ill NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 4-F IV NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 5-F V NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 13-F VI NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 14-F cc: P. J. Bamford (NRC}, w/e K. M. Kennedy (NRC), w/e B. K. Singal (NRC), w/e N. H. Taylor (NRC), w/e Senior Resident Inspector (NRC), w/e

Enclosure I to RA 17-0067 NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 2-F (6 pages)

May 16, 2017 NRC COMPLIANCE -LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls Issue No: 2-F Request:

(Steve Monarque, USNRC-Email) Spent Fuel Pool Level Instrumentation (SFPIS) RAI 4/5/8:

The responses to these RAls do not include the seismic design of the mounting for the electronics equipment (enclosures, displays, pull boxes, and transmitters) and the conduit supports. Please provide the missing information.

Response

Spent Fuel Pool Instrumentation System (SFPIS) equipment underwent seismic testing by the supplier (Westinghouse) prior to installation at Wolf Creek Generating Station (WCGS):

  • Applicable components of the instrument system are rated by the manufacturer (or otherwise tested) for shock and vibration at levels commensurate with those of postulated design basis event conditions in the area of instrument system component.

The following SFPIS components underwent seismic testing before installation per Westinghouse Report EQ-QR-269, Table 2.1-1:

o Seismic electronic and wall enclosures o Sensor Head Unit Mounting Bracket o Coaxial signal cable (120 feet) o Level probe (312 inches) o Launch plate o Antenna (including cable) (Wireless not used at Wolf Creek Nuclear Operating Corporation (WCNOC))

o Antenna bracket (Wireless not used at WCNOC) Straight connector o 90 degree connector o SKINTOP Glands o Level Sensor Enclosure o Surge/EMC Filter Enclosure - This is an option. This option which uses a separate EMC Filter Enclosure is not used at WCNOC. WCNOC's system has the line filter in a separate compartment of the Electronics Enclosure.

o Sensor head unit mounting bracket

  • Seismic qualification testing for these SFPIS components was reported in Westinghouse Report EQ-QR-269. The testing was performed in accordance with IEEE Std 344-2004, which is endorsed by United States Nuclear Regulatory Commission (USNRC)

Regulatory Guide (RG) 1.100. The Required Response Spectra (RRS) for this program includes the 10% margin recommended by IEEE Std 323-2003. The test program objective was satisfied by performing seismic testing to the Safe Shutdown Earthquake

. (SSE) and Hard Rock High Frequency (HRHF) spectra taken from WNA-DS-02957-GEN.

May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls five successful OBE level tests were required, followed by two successful SSE level tests and one successful HRHF level test.

NOTE: Regarding pull boxes: WCGS's design of the Spent Fuel Pool Level Instrumentation (SFPLI) did not include the installation of pull boxes.

  • Per Reference 3, Seismic Evaluation and Qualification Sections (Page 16 of 33):

o The sensor bracket for the sensing probe is designed according to the plant design basis for SSE seismic hazard curve at the 2047'-6" Fuel Building elevation, with an added conservatism of two times the acceleration values.

These Floor Response Spectra (FRS) curves are chosen from Reference 7. The SNUPPS enveloped FRS is used in Reference 6. Loads considered in the evaluation of the sensor bracket and its mounting are:

i. Static loads including the dead weight of the sensor bracket in addition to the weight of the sensor probe, pipe guard and cabling.

ii. Dynamic loads including the seismic load due to excitation of the dead weight of the system in addition to the hydrodynamic effects resulting from the excitation of the Spent Fuel Pool (SFP) water.

o Response Spectra Analysis (RSA) has been performed for the SSE seismic evaluation of the sensor bracket. The analysis uses Finite Element Analysis (FEA) software (GT STRUDL) using SNUPPS FRS at the operating deck elevation (2047'-6") in the Fuel Building (i.e., mounting floor elevation). Damping values are according to RG 1.61, Table-1 for SSE and consistent with the design basis of the station.

o The material properties that are used for the bracket and its mounting take into consideration the environmental conditions in the SFP area following an event.

The design of the bracket and its mounting maintains a design margin of 10% or more from the plant design basis criteria. Hydrodynamic effects on the mounting bracket are evaluated using Reference 9.

o Effects of shock and vibration on SFPIS components used during and following any applicable event for installed components are considered. All components located within the SFP are passive components, and are inherently resistant to shock and vibration loadings. These include the stainless steel sensor cable probe, sensor bracket (with sensor probe coupler) and interconnecting sensor coax cable. Active electronic components, located outside the SFP building, are permanently and rigidly attached to seismic racks or structural walls, and are not subject to significant shock and vibration loadings.

o Per Reference 3 (Page 5 of 33), the mountings of the primary and backup elements, primary and backup level indicating transmitters, and primary and backup level indicators were classified as meeting Seismic II/I criteria.

Page 2 of 6

May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls

  • The WCNOC installation of the SFP Mounting Bracket was seismically qualified per Reference 6. The analysis determined that all members and connections have Interaction Ratios (IRs) below the allowable limit and are therefore acceptable.
  • The WCNOC installation of the SFPIS primary and backup transmitter and their enclosures, the two coil cable spooling enclosures, and their respective mountings were seismically qualified per Reference 4. The analysis determined the Test Response Spectra (TRS) used to seismically qualify the components exceeded the FRS of the installed enclosure in the Auxiliary Building; therefore, demonstrating the installed enclosures are seismically qualified.
  • The WCNOC installation of the SFPIS Head Unit Enclosure was seismically qualified per Reference 5.
  • The WCNOC installation of SFPIS conduit was performed in accordance with WCGS design documents (E-1 R series conduit drawings). The conduits are seismically mounted per Reference 29 and C-1600 series details which are safety related, seismic mounting details.

Request:

Please provide additional information to demonstrate that "Seismic Ill/ criteria" satisfies NRG Order EA-12-051 which requires SFP level instrument to be mounted to retain its design configuration during and following the maximum seismic ground motion.

Response

The SFP and Fuel Building are Seismic Class 1 structures, so any mounting to them must be done with Class 1 or II/I connections. Per Reference 3, the sensor bracket for the sensing probe is designed according to the plant design basis for SSE seismic hazard curve at the 2047'-6" Fuel Building elevation, with an added conservatism of two times the acceleration values. The item that is being supported (i.e. the sensor probes) are non-safety related (NSR).

They have been seismically tested by Westinghouse and have been demonstrated they are rugged enough to survive the worst seismic event (refer to Reference 30). Consequently, the mounting classification of the anchor-mounted Seismic Class 1 bracket securing the NSR probe is considered a Special Scope Seismic Category 11/1 support to the Fuel Building floor, elevation 2047'-6". Therefore, the stainless steel sensor cable of the SFPIS will remain in place, will not threaten the SFP, and will continue to function during and following a SSE event.

Page 3 of 6

May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls Request:

Regarding the RAJ 2-F response, I think that there is still a bit of a misunderstanding. The original question concerned the electronics equipment and conduit supports. Your original response talked, in part, about the transmitters and level indicators (electronics) being classified as seismic Ill/. That was the genesis of our follow-up question.

Your follow-up response discusses the probes, bracket and cables in the SFP area. While that is good information, that was not what we are primarily trying to ascertain. We are trying to understand the seismic capability of the electronics equipment and conduit supports (i.e. the rest of the system).

Can you revise the RAJ 2-F response to address not only the components in the SFP area, but the electronics as well?

Response

Per Reference 3, the installation of SFPIS conduit was performed in accordance with WCGS design documents (E-1 R series conduit drawings). The Reference 3 instructions that detail the installation of conduit cite the use of the Reference 29 to install the conduit supports which incorporates the Class-1 seismic requirements. All hardware used to install the conduit and raceways were safety-related. Therefore, the conduits are seismically Class 1 mounted per WCGS drawings E-1 R8900 and C-1600 series details which are a safety related, seismic mounting detail.

As described in the modification in Reference 3, the sensor electronics module (SEM) is mounted using a seismic Class 1 bracket inside enclosures that are seismically mounted to ensure their function following a SSE. The remote primary and backup indicator enclosures which house the input/output (1/0) cards, DC power supply for the SEM, and indicator display are mounted Class 1 seismically such that they would survive a SSE.

Per Reference 30, the entire configuration of electronics within the SFPIS enclosures was seismically tested by Westinghouse to meet seismic design requirements of WNA-DS-02957-GEN Section 4.9 which included the following specifications for seismic:

  • DS-02957-1840: The SFPIS shall be designed to maintain functionality and physical integrity before and after five OBEs and one SSE.
  • DS-02957-502: The SFPIS's seismic adequacy shall be demonstrated using the methodology defined in IEEE 344-2004 for seismic category I. This equipment shall maintain functionality and physical integrity before and after five OBEs and one SSE.

The SFPIS electronics which are housed inside Seismic Class 1 mounted enclosures outside the SFP area, are seismically tested/demonstrated to more than meet Class 1 seismic qualifications and therefore will remain functional during ELAP with a BDBEE seismic event.

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May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls

References:

1. J-481-0032, Westinghouse Report EQ-QR-269, Design Verification Testing Summary Report for the SFPIS, Revision 5.
2. J-481-0043, WNA DS 02957 GEN, Spent Fuel Pool Instrumentation System Design Specificatic;m, Revision 4.
3. Design Change Package 014403, Spent Fuel Pool Instrumentation System.
4. EC-C-007 Revision 2, Westinghouse CN-PEUS-14-24, Seismic Qualification of the SFPIS Transmitter Enclosure for Wolf Creek Generating Station, Revision 1.
5. EC-C-008 Revision 0, Westinghouse CN-EQT-14-19, Seismic Qualification of Spent Fuel Pool Instrumentation System Sensor Head Unit Enclosure, Revision 1.
6. EC-C-009, Revision 1, Westinghouse CN-PEUS-13-32,
  • Seismic Analysis of the SFP Mounting Bracket for Wolf Creek Generating Station, Revision 1.
7. Bechtel Calculation 10-19-F, Refined 'As-Built' Floor Response Spectra Curves, Revision 0.
8. Bechtel Calculation 03-74.94-F, Verify Seismic II/I Conduit Support Limitations, Revision 0.
9. TID-7024, Nuclear Reactors and Earthquakes, dated August 1963.
10. Drawing E-1R1924, Raceway Sections & Details Auxiliary Building, Revision 01.
11. Drawing E-1 R3513, Exposed Conduit Control Building Area 1 EL. 2032'-0", Revision 19.
12. Drawing E-1R3613, Exposed Conduit Communication Corridor Area-1 EL. 2047'-6", Revision 19.
13. Drawing E-1R3614, Exposed Conduit Control Building Area-1, EL. 2047'-6", Revision 13.
14. Drawing E-1 R6311, Raceway Plan Fuel Building Area-1 EL. 2047'-6", Revision 09.
15. Drawing E-1R6903, Raceway Sections & Details Fuel Building, Revision 01.
16. Drawing E-1R1513, Exposed Conduit Auxiliary Building Area-1 EL. 2047'-6", Revision 01.
17. Drawing E-1R1523A, Exposed Conduit Auxiliary Building Area-2 EL. 2047'-6", Revision 03.
18. Drawing E-1R1523B, Exposed Conduit Auxiliary Building Area-2 EL. 2047'-6", Revision 05.
19. Drawing E-1R1523C, Exposed Conduit Auxiliary Building Area-2 EL. 2047'-6", Revision 05
20. Drawing E-1 R1534, Exposed Conduit Auxiliary Building Part Plan Area-3 EL. 2047'-6",

Revision 05.

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May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls

21. Drawing E-1R1914, Raceway Sections and Details Auxiliary Building, Revision 13 .
22. Drawing E-1R1920, Raceway Sections and Details Auxiliary Building, Revision 01.
23. Drawing E-1R1921, Raceway Sections and Details Auxiliary Building, Revision 01.
24. Drawing E-1 R 1922, Raceway Sections and Details Auxiliary Building, Revision 01.
25. Drawing E-1R1923, Raceway Sections and Details Auxiliary Building, Revision 01.
26. Drawing C-0604(0), Typical Details Conduit Supports Sheet 4, Revision 17.
27. Drawing C-1602, Typical Details Conduit Supports, Revision 02.
28. Drawing C-1605, Typical Details Conduit Supports Sheet 5, Revision 01.
29. E-1 R8900, Raceway Notes, Symbols and Details, Revision 28.
30. Westinghouse Report WNA-TR-03149-GEN, SFPIS Standard Product Final Summary Design Verification Report, Revision 1.

Page 6 of 6

Enclosure 11 to RA 17-0067 NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 3-F (8 pages)

June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls Issue No: 3-F Request:

(Steve Monarque, USNRC - Email) RAI 6: NEI 12-02, Section 3.4 states, in part, that "The temperature, humidity and radiation levels consistent with conditions in the vicinity of the SPF and the area of use considering normal operational, event and post-event conditions for no fewer than seven days post-event or until off-site resources can be deployed by the mitigating strategies resulting from Order EA-12-049 should be considered."

Please provide the TIO for 7 days when the pool water level drops to Level 3. Please note that in addition to directly answering. to the question, all references must be either docketed or posted in ePortal for verification.

Response

NEI 12-02, Section 3.4, is associated with equipment qualification of the Spent Fuel Pool Instrumentation System (SFPIS). Below is a revised response to the original Request for Additional Information (RAI) 6 which encompassed a broad range of environmental conditions during Extended Loss of AC Power (ELAP) and survivability of the installed SFPIS design that is installed at Wolf Creek Generating Station (WCGS).

SFPIS Design Specification:

Per Reference 2, for environmental conditions inside the SFP area:

  • Per Design Specification DS-02957-779, under Operating Conditions the SFPIS level sensor installed in the Spent Fuel Pool (SFP) room shall function in the presence of 1E07 Rv (gamma) radiation levels which define the SFP environment acceptance criteria.
  • Per Design Specification DS-02957-825, the SFPIS equipment located in the SFP area is subjected to the temperature, humidity, and* radiation levels defined in the Beyond Design Basis column in Table 4.8-1, for an extended 7-day period. The basis for the Total Integrated Dose (TIO) is provided in Westinghouse documents LTR-SFPIS-13-35 and LTR-REA-13-85. This same table is invoked in the Design Change Package (DCP) 014403 Engineering Disposition.
  • Below is a portion of Table 4.8-1 from the SFIS Design Specification:

Table 4.8-1. Environmental Conditions in Spent Fuel Pool Area Normal Beyond design Basis Temperature 50-140°F 212°F Pressure Atmospheric Atmospheric Humidity 0-95% RH 100% (Saturated Steam)

Radiation TIO 1E03 Rv 1E07 Rv (above pool)

s; 1E09 Rv 1E07 Rv Radiation TIO (Only the probe's stainless steel cable (Only the probe's stainless steel (1' above top of and weight are exposed for period cable and weight are exposed for 7 fuel rack) defined in Specification DS-02957-615) days)

Page 1of8

June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls Per WCGS Design Specification, J-481-0043 (Reference 2), for environmental conditions outside the SFP area:

  • Per Design Specification DS-02957-907, the sensor electronics, electronics enclosure, battery cabinet, level indications, and optional temperature indications shall be mounted outside the SFP environment in an area that protects the active electronics from the radiation and high temperatures that a postulated loss of water inventory in the SFP could cause.
  • Per Design Specification DS-02957-792, the SFPIS sensor electronics located outside the SFP area shall operate and withstand the temperature, humidity, and radiation levels defined in the Abnormal for Sensor Electronics Only column in Table 4.8-2.
  • Per Design Specification DS-02957-840, the SFPIS equipment (other than the level sensor electronics) located outside the SFP area shall operate at the temperature, humidity, and radiation levels defined in the Normal column in Table 4.8-2.
  • Per Design Specification 08'-02957-855, the SFPIS equipment (other than the level sensor electronics) located outside the SFP area shall operate at the radiation levels defined in the Abnormal column in Table 4.8-2.
  • Below is a portion of the Table 4.8-2 from the SFIS Design Specification:

Table 4.8-2. Environmental Conditions Outside of the Spent Fuel Pool Area Normal Abnormal Abnormal Sensor Electronics only Temperature 50-120°F 50-140°F 212°F Pressure Atmospheric Atmospheric Atmospheric Humidity 0-95% RH 0-95% (Non-CondensinQ) 0-95% (Non-CondensinQ)

Radiation TIO (above :s; 1E03 Rv :s; 1E03 Rv S1E03 Rv pool)

That portion of the SE Tracker 6-D, Spent Fuel Pool Level Instrumentation (SFPLI) RAI 6 response relevant to Spent Fuel Dose and the radiological environment to which a portion of the SFPIS is exposed to, is repeated below:

  • TIO for SFPLI:

o The SFPLI is mounted slightly above the top of the spent fuel. The TIO is dependent upon the shielding (water) between the spent fuel and the Radar Level Probe elevation. The Westinghouse Radiation Analysis team provided a dose rate with the water level in the SFP at the top of the racks at a value that was slightly less than 7E+03 R/h. This evaluation is documented in Westinghouse letter LTR-REA-13-85. For the purposes of calculating a maximum reasonable dose, this rate was increased to 1E+04 R/h. For seven days (168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />) the total dose is 1.68E+06 R, which was rounded up to Page 2 of 8

June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls 2E+06 R, and then finally multiplied by five to allow for some margin in regards to the distribution of the spent fuel assemblies in the pool.

o The Engineering evaluation saw no reasonable way to exceed 10 Mrad for the beyond design basis TIO at one foot above the fuel rack according to J-481A-00032, Table 4.3-1 Expected TIO, page 37of179.

o It should be noted that WCGS FLEX Support Guidelines initiate actions to prevent the water level in the SFP to fall to Level 3. If these guidelines are implemented properly, the water level in the pool will be at least ten feet above the top of the racks. According to LTR-REA-13-85, this additional shielding will reduce the dose rate by five orders of magnitude.

  • Auxiliary Building Dose o Personnel Hatch Area, Room 1507, area where the Transmitters are located.

o During a Beyond Design Basis (BOB) event, the expected radiological conditions (dose rate and TIO) in the Auxiliary Building are consistent with normal operating conditions identified in Wolf Creek EQSD EQ Design Basis Document based on the following:

  • Spent Fuel Pool makeup capabilities (>250gpm) exceeds calculated full core offload boil off of approximately 136 gpm.

o In Room 1507 (EQSD-1 R9, page 296 of 318), the Dose Rate is <0.0025 R/hr.

The TIDs are the rates multiplied by 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />, or 7 days, which calculates to TIO= 0.42 R.

  • Heating, ventilation, and air conditioning (HVAC) Areas, Rooms 1501 & .1512, are where the primary and backup electronics cabinets are located:

o In Room 1501 (EQSD-1 R9, page 309 of 318), the dose rate is <0.0005 R/hr.

The TIDs are the rates multiplied by 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />, or 7 days, which calculates to TIO = 0.084 R.

o In Room 1512 (EQSD-1 R9, page 309 of 318), the dose rate is <0.0005 R/hr.

The TIDs are the rates multiplied by 168 hours0.00194 days <br />0.0467 hours <br />2.777778e-4 weeks <br />6.3924e-5 months <br />, or 7 days, which calculates to TIO = 0.084 R.

NOTE: Per EPRI Report 1021067, Section 3.2.2.2, the radiation field threshold that could potentially affect the semiconductors within the transmitter begins at 103 Rads that is well above any radiation field the SFPLI transmitter instrumentation would be exposed to during normal power operation or ELAP.

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June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls SFPLI DCP:

  • (Design Basis Function) The level instrument systems were tested for reliability at temperature, humidity and radiation levels consistent with the SFP water at saturation conditions for an extended period. To this end, they shall withstand the radiological conditions for a normal refueling quantity of freshly discharged (100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br />) fuel with the SFP water at approximately 1ft. above the fuel racks, work within the SFP at temperatures of 212°F and 100 percent relative humidity environment, boiling water and/or steam environment, and a concentrated borated water environment.
  • Table 4.8-1 is reflected as a design requirement for the SFPIS components survivability within the environment of the SFP under ELAP conditions.
  • According to Design Bases Document EQSD-1, the environmental conditions for normal operations of the SFPIS are within operating margins.
  • During a BDB event, the expected radiological conditions (dose rate and TIO) in the Personnel Hatch Area and Control Building are consistent with normal operating conditions identified in EQSD-1 based on the following:

o During a BDB event, the RCS remains intact due to the strategies outlined in Procedure AP 21A-002, Diverse and Flexible Coping Mitigation Strategies (FLEX) Program, Section 6. 7.

o During a BDB event, SFP cooling is maintained due to strategies outlined in AP 21A-002, Section 6.10.

  • Furthermore, maximum pressures are based upon postulated pipe breaks for all rooms in the Auxiliary Building assuming initial conditions of atmospheric pressure. Pipe breaks are not assumed to coincide with a BDBEE. Pressures and radiological doses resulting from a Design Basis Accident (DBA) are not requirements for SFPIS to meet; therefore, the environments where SFPIS components are located are acceptable for normal and BDBEE conditions.

In summary, Westinghouse qualified the SFPIS equipment to radiological levels which bound rad levels in the SFP area and areas outside the SFP area expected during an ELAP event.

These components were installed at WCGS consistent with those design specifications.

Therefore, under BDB ELAP events the SFPIS is expected to continue to function as designed through the ELAP duration.

Request:

(Discussed during teleconference on February 23, 2017) Provide a basis for the "no reasonable way to exceed 10 Mrad" conclusion of the engineering evaluation. At a minimum, the licensee needs to-provide a reference for clarification as to what the levels specified in FSG-11 for SFP makeup correspond to in terms of water level above the top of the fuel.

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June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls

Response

WCNOC has no history of performing an analysis of TIO with a SFP level at Level 3 (2022' 4.25" Elevation or 15" above top of racks). However, as we discussed on February 23, 2017, an alternate approach would describe the WCNOC approach to managing SFP level during ELAP to demonstrate that the SFP level would never be allowed to lower to Level 3.

WCNOC response during ELAP for management of SFP inventory is detailed in Procedure

  • EMG C-0, Loss of All AC Power, and Procedure FSG-11, Alternate SFP Makeup and Cooling, for Modes 1-4, and Procedure OFN NB-034, Loss of All AC Power - Shutdown Conditions, and FSG..:11 for Modes 5 and 6. In both cases, the measurable loss of SFP inventory occurs when the SFP reaches the point of boiling. As determined in Westinghouse Calculation CN-SEEll-12-35, the time to boil for Modes 1-4 with normal decay heat loads in the SFP is 8.9 hours1.041667e-4 days <br />0.0025 hours <br />1.488095e-5 weeks <br />3.4245e-6 months <br />. For maximum decay heat loads such as during core off-load in Modes 5/6, the time to boil is 2.4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />. The action to pre-stage the FLEX *Core Cooling Pump just after entering Mode 5, is to expedite placing it into service for RCS makeup because of this relatively short time until the SFP reaches boiling. In Modes 1-4 or Modes 5 and 6, the ELAP response in Procedure FSG-05, Initial Assessment and Flex Equipment Staging, requires the staging the SFP makeup equipment as early as possible before the SFP begins to impact Fuel Building environment.

The following is an outline of the actions taken to ensure the SFP level never reaches Level 3:

Modes 1-4 Procedure EMG C-0, Loss of All AC Power, Step 43 directs the operator to verify the SFP water level is:

  • Greater than -28 inches (22.56 feet above storage racks) as read on the standard narrow range indicators EC-Ll-39A (Control Room), or EC-Ll-39B (NB Switchgear Room A) or its associated EC-LIT-39 (NB Switchgear Room B), or
  • Greater than +267 inches (22.67 feet above storage racks) as read on the FLEX SFP Wide Range Level Indicators EC Ll-59 and EC Ll-60 (Control Room A/C Room A and B, respectively).
  • If operators cannot verify that the SFP water level is greater than the -28 inches Narrow Range or +267 inches Wide Range, and if the fire protection system is available, the operators will place a firehose on a handrail and have it spray directly into the SFP. This action will restore the SFP level to the elevation of the SFP pump discharge pipe entry point which is located at Elevation 2044.5 feet or 23.4 feet above storage racks.

If the fire protection system is not available, then the operators are directed to perform FSG-11 for alternate SFP makeup.

Modes 5-6 Procedure OFN NB-034, Loss All AC Power-Shutdown Conditions, Step 37.a directs operators to verify the refuel pool level is greater than or equal to the Tech Spec level (lower mark on SFP ladder or reactor pressure vessel (RPV) level indication >375 inches on the Shutdown Range Level Indicator. If the refuel pool level is not above this elevation, the operators are directed to Page 5 of 8

June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls perform Procedure FSG-14, Shutdown RCS Makeup, whereupon they deploy the pre-staged FLEX core cooling pump to initiate RCS makeup from the RWST.

Then Procedure OFN NB-034, Step 37.c, has the operators check that the SFP water level is approximately the same as the Refuel Pool water level. The operators are then directed to FSG-11 to initiate alternate SFP makeup and cooling.

OFN NB-034 Step 48 directs the operator to periodically check SFP water level to ensure that it is maintained:

  • Greater than -28 inches (22.56 feet above storage racks) as read on the standard narrow range indicators EC-Ll-39A (Control Room), or EC-Ll-39B (NB Switchgear Room A) or its associated EC-LIT-39 (NB Switchgear Room B), or
  • Greater than +267 inches (22.67 feet above storage racks) as read on the FLEX SFP Wide Range Level Indicators EC Ll-59 and EC Ll-60 (Control Room A/C Rooms A and B, respectively).

If Operators cannot verify that the SFP water level is greater than the -28 inches Narrow range or +267 inches Wide range, and if fire protection system is available, the operators will place a firehose on a handrail and have it spray directly into the SFP to restore level to the elevation of the SFP pump discharge pipe entry point which is located at elevation 2044.5 feet or 23.4 feet above storage racks.

However, just as in the case of Modes 1-4, if the fire protection system is not available, then operators are directed to Procedure FSG-11 for alternate SFP makeup.

FSG-11, Alternate SFP Makeup and Cooling:

As discussed the FLEX SFP makeup and spray equipment are staged early in the ELAP per FSG-5. The first steps in FSG-11 are to deploy the FLEX SFP makeup and cooling equipment.

The operators are provided a choice as to how to provide SFP makeup, either to use the makeup connections that spray into the pool or the makeup option through the SFP suction line depending on their assessment of the SFP conditions. The FLEX SFP pump will provide the necessary makeup from either the primary source, Reactor Water Storage Tank (RWST) or the alternate source, Condensate Storage Tank (CST). Key steps include:

~ Makeup to the SFP is based on maintaining water level:

  • Greater than -28 inches (22.56 feet above storage racks) as read on the standard narrow range indicators EC-Ll-39A (Control Room), or EC-Ll-39B (NB Switchgear Room A) or its associated EC-LIT-39 (NB Switchgear Room B), or
  • Greater than +267 inches (22.67 feet above storage racks) as read on the FLEX SFP Wide Range Level Indicators EC Ll-59 and EC Ll-60 (Control Room A/C Rooms A and B, respectively).

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June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls

>-- Makeup to the SFP is stopped when the water level reaches or exceeds:

  • +6 inches (25.4 feet above storage racks) as read on the standard narrow range indicators EC-Ll-39A (Control Room), or EC-Ll-39B (NB Switchgear Room A) or
  • +304.75 inches (25.81 feet above storage racks) as read on the FLEX SFP Wide Range Level Indicators EC Ll-59 and EC Ll-60 (Control Room A/C Rooms A and B, respectively).

OR

  • Local observation of SFP level is within 12 inches from the top of the SFP.

>-- The operators continue monitoring the SFP water level. The SFP makeup or spray is re-commenced once SFP level drops:

  • Below -28 inches (22.56 feet above storage racks) as read on the narrow range SFP level indicators EC-Ll-39A (Control Room), or EC-Ll-39B (NB Switchgear Room A) or its associated EC-LIT-39 (NB Switchgear Room B), or
  • Below +267 inches (22.56 feet above storage racks) as read on the FLEX SFP Wide Range Level Indicators EC Ll-59 and EC Ll-60.

These actions establish the SFP level control band between 22.56 feet above the fuel storage racks and 25.4 feet above the fuel storage racks, based on the use of the Narrow Range indicators, and 22.67 feet to 25.81 feet above the fuel storage racks if using the new FLEX SFP Wide Range Level Indicators. Therefore, the strategy for the SFP never allows the SFP level to lower or reach the Level 3 elevation in the SFP. Consequently, the SFPIS probe will never be exposed to a radiation field capable of delivering 10 Rads over a seven day ELAP.

NOTE: SFP water level elevations points of interest:

  • The elevation of SFP normal level and reference instrument zero for Narrow Range indicators is 2046.0 feet. This is 1.5 feet from top of SFP edge and 24.9 feet above top of racks.
  • The elevation of SFP Level 3 is 15 inches above top fuel racks or 2022.35 ft.
  • The FLEX Wide Range SFPIS instrument zero is at 2021.52 feet elevation or 5 inches above top of fuel racks.
  • The elevation of the top of the SFP storage racks is 2021.1 feet.
  • The elevation of SFP pump discharge into the pool is 2044.5 feet which is 1.5 feet below instrument zero or 23 feet 4. 75 inches above the SFP racks.
  • SFP Level Narrow Range indication of -28 inches equates to Elevation 2043' 8" which is 22.56 feet above the storage racks.

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June 1, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls

  • The elevation of the new FLEX SFP Wide Range Level indication of +267" equates to 2043.8 feet, or 22.67 feet above the storage racks.

References:

1. Westinghouse Letter LTR-REA-13-85, Summary of Discussions Regarding Radiation Levels at Radiation Detector Locations in the Spent Fuel Pit, November 20, 2013.
2. J-481-0043, Westinghouse WNA-DS-02957 GEN, Spent Fuel Pool Instrumentation System Design Specification, Revision 4.
3. J-481A-00032, Westinghouse EQ-QR-269, Design Verification Testing Summary Report for the Spent Fuel Pool Instrumentation System, Revision 5.
4. J-481A-00071, Full Range Level Measurement, Revision W01.
5. WCRE-03, Wolf Creek Tank Document, Revision 30.
6. WCOP-24, Operations EMG/OFN Setpoints, Revision 12 ..
7. EPRI Report 1021067, Plant Support Engineering: Nuclear Power Plant Equipment Qualification Reference Manual, Revision 1.
8. EQSD-1, Equipment Qualification Design Basis Document, Revision 7.
9. Design Change Package 014403, Spent Fuel Pool Instrumentation System.
10. Procedure EMG C-0, Loss of All AC Power, Revision 39.
11. Procedure OFN NB-034, Loss of All AC Power-Shutdown Conditions, Revision 27.
12. Procedure AP 21A-002, Diverse and Flexible Coping Mitigation Strategies (FLEX)

Program, Revision OB.

13. FSG-05, Initial Assessment and FLEX Equipment Staging, Revision 0.
14. FLEX Support Guide FSG-11, Alternate SFP Makeup and Cooling, Revision 0.

Page 8 of 8

Enclosure Ill to RA 17-0067 NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 4-F (2 pages)

May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls Issue No: 4-F Request:

(Steve Monarque, USNRC-Email) SFPIS RAI 13: NE/ 12-02, Section 4.3 states, in part, that, "The primary or back-up instrument channel can be out of service for testing, maintenance and/or calibration for up to 90 days provided the other channel is functional. Additionally, compensatory actions must be taken if the instrumentation channel is not expected to be restored or is not restored within 90 days. If both channels become non-functioning then initiate actions within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore one of the channels of instrumentation and implement compensatory actions (e.g., use of alternate suitable equipment or supplemental personnel) within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />."

Please provide a description of the compensatory measures to be taken in the event that one or both channels are non-functioning, as described in the above NE/ 12-02 guidance.

Response

Procedure AP 21A-002 (Formerly AP 06-005), Diverse and Flexible Coping Mitigation Strategies (FLEX) Program, Section 6.17, provides programmatic guidance for managing the availability of both channels of the Spent Fuel Pool Level Instrumentation (SFPLI) consistent with the requirements of NEI 12-02, Industry Guidance for Compliance with NRC Order EA 051, "To Modify Licenses with Regard to Reliable Spent .Fuel Pool Instrumentation."

  • AP 21A-002 (Reference 4), Step 6.17.5.1, states that, "One channel of FLEX SFP Wide Range Level Instrumentation can be out of service for 90 days, if the other channel is functional. If one channel is out of service for greater than or equal to 90 days, then compensatory actions must be implemented."
  • Reference 4, Step 6.17.5.2, states that, "If both channels of FLEX SFP Wide Range Level Instrumentation become non-functioning, then initiate action within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore one channel (o service or initiate compensatory within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />."

Per Reference 1, the operations department performs daily checks on the SFPLI to verify they are operational. The daily checks compare the level variance between both FLEX SFPLI channels. In addition, each FLEX SFPLI channel is checked against actual SFP level.

Discrepancies are recorded on the reading sheet and reported to the Control Room. The discrepancy results in the generation of a Condition Report (CR) and an entry into the Equipment Out-Of-Service Log (EOL). The allowed Out-Of-Service (OOS) time for the FLEX SFPLI channel is 90 days. This OOS time is tracked by the operations department in the EOL.

The CR is entered into the Corrective Action Program (CAP), where it is reviewed by plant staff and assigned to the appropriate department to repair/restore the equipment within the allowed OOS time.

Per Reference 4, Step 6.17.5.1, " ... Compensatory actions consist of either the use of increased operator rounds or suitable alternate equipment." Within the CR process, the determination of whether compensatory actions are required during the OOS time would be performed and administered as CR actions. This would depend upon the nature of the failure, and length of expected repair time. Compensatory actions could include the use of increased rounds on the remaining FLEX SFPLI channel, or the use of temporary equivalent instrumentation under a temporary configuration change (TCC) process per Procedure AP 211-001, Temporary Configuration Change.

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May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls I -

Request:

Section 4.3 of NE/ 12-02, as endorsed by NRG JLD-ISG-2012-03, states, in part, that If both channels become *non-functioning then initiate actions within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore one of the channels of instrumentation and implement compensatory actions (e.g., use of alternate suitable equipment or supplemental personnel) within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

The NRG staff notes that the Wolf Creek strategy of maintaining the SFP level instrument channels' availability (AP 06-005 step 6.17.5.2) is not consistent with NE/ 12-02, which requires both actions to restore one channel to service and compensatory actions when both channels become non-functioning. Please confirm whether this is an intended deviation from NE/ 12-02.

If yes, please provide a justification. If not, please revise the applicable program/procedure(s) as appropriate.

Response

Procedure AP 21A-002 (Reference 4), Step 6.17.5.2, was intended to mirror the guidance in NEI 12-02 (Reference 3). Therefore, Reference 4, Step 6.17.5.2 was revised to match Reference 3 as follows:

"If both channels of FLEX SFP Wide Range Level Instrumentation become non-functioning, then initiate action within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore one channel to service and initiate compensatory actions described in 1 above within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />."

The change to Procedure AP 21A-002 has been approved, and was released to the field with this correction.

References:

1. Procedure CKL ZL-001, Auxiliary Building Reading Sheets, Revision 98A.
2. Procedure AP 211-001, Temporary Configuration Changes, Revision 12.
3. NEI 12-02, Industry Guidance for Compliance with NRC Order EA-12-051, "To Modify Licenses with Regard to Reliable Spent Fuel Pool Instrumentation," Revision 1.
4. Procedure AP 21A-002, Diverse and Flexible Coping Mitigation Strategies (FLEX)

Program, Revision OB.

5. Condition Report 00111438-01-01 closure.

Page 2 of 2

Enclosure IV to RA 17-0067 NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 5-F (3 pages)

May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls Issue No: 5-F Request:

(Steve Monarque, USNRC-Email) The NRG staff audited Westinghouse's SFP level instrumentation design verification analyses and performance. The staff reviewed the vendor's SFP level instrumentation system design specifications, calculations and analyses, test plans, and test reports. The staff issued an audit report on August 18, 2014. Regarding the Electromagnetic Compatibility (EMC) review, the audit report states that, As a result of the NRG staff's evaluation of the EMC testing results, the staff identified a generic open item applicable to all licensees using this technology to identify any additional measures, site-specific installation instructions or position taken to address the potential effect of an EMC event on the SFPI equipment."

The NRG staff requests additional information or an assessment of potential susceptibilities of Electromagnetic Interference/Radio Frequency Interference (EMllRFI) in the areas where the SFP level instrument located and how to mitigate those susceptibilities.

Response

The Spent Fuel Pool Level Instrumentation System (SFPLIS) provided by Westinghouse has been designed and tested to Electromagnetic Interference/Radio Frequency Interference (EMl/RFI) standards as stated in Reference 1.

The body of the letter of Reference 1 describes how grounding and shielding was configured for the test installation. Reference 1 has an attached sketch titled, "Basic Configuration (EMC),"

which provides the details of the tested configuration. Reference 2 confirmed the letter, but appeared to add EMI flexible and rigid conduit to the tested configuration.

Within the Design Change Package (DCP) 014403 (Reference 3), several features were included to reduce system susceptibility to EMl/RFI including:

  • Low impedance grounding of all SFPIS components.
  • The use of EMl/RFI resistant flexible conduit.
  • The use of rigid conduit.
  • Special EMl/RFI gasketing including sealing compounds for condulet covers ..
  • The use of glands to ground signal cable at the entry point of panels.

Wolf Creek Generating Station's (WCGS's) installation is as follows: Starting at the probe, the Launch Plate Bracket for the probe is solidly grounded to the plant ground. The coaxial cable from the probe to the Sensor/Transmitter is installed in EMl/RFI flexible conduit transitioning to rigid conduit. Condulets have conventional gaskets replaced with EMl/RFI gaskets and sealing compounds. EMl/RFI flexible conduit is used leading into and out of penetrations.

The four 20 mA signal from the Sensor/Transmitter to the Electronics Enclosure (LI) were run in rigid conduit. The cable used for this is two conductor twisted shield pair, with a shield consisting of Mylar foil and a drain wire. At the Sensor/Transmitter, the drain wire is capacitively grounded, with a 470 pF capacitor and solidly grounded at the entrance to the LI end with a gland.

Page 1of3

May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls The gland makes a 360° ground out of the drain wire by using a short length of braided shield over the cable end. Note that the Sensor!Transmitter and LI are also solidly grounded to the plant ground.

The use of a solid ground at one end of a signal cables *shield and a solid ground at the other end is a recommendation from IEEE 1050-2004, Section 6.2. 7, and has been used successfully for WCGS digital upgrades.

Looking at the Westinghouse testing documentation, the SFPLIS failed IEC 61000-4-4, Electrical Fast transient I Burst Immunity Test at +/-2 kv, and also failed IEC 61000-4-3, Radiated Susceptibility, Electrical field at +/-2 kv.

Risk of EMl/RFI is further reduced by locating the transmitter boxes and electronic enclosures not in close proximity to any sources of EMl/RFI, including large induction motors, variable frequency drives, uninterruptible power supplies (UPS) and other sources of power switching.

As stated in Reference 3, "due to the close proximity between the Control Room and the SFPIS display locations, use of wireless handheld radios or other equipment for communications will not be necessary."

Operational measures to reduce EMl/RFI further include the administrative control over the use of wireless communications such as cell phones and radios. Wireless devices including low power cell phones, laptops, electronic pads, and radios are governed by Reference 4, and require approval before being allowed in the power block of the plant. This procedure prohibits use of personal wireless devices in the power block and establishes radio exclusion zones.

Request:

It is not clear how "wireless handheld radios or other equipment for communications will not be necessary" is monitored and reinforced.

Note: Some other sites that utilize Westinghouse Spent Fuel Pool Level Instrumentation (SFPLI) have implemented the following to mitigate potential EMllRFI susceptibilities:

  • Establishing "Radio Exclusion" zones encompass the SFPLI electronics based on post modification test results. A typical test includes keying a two-way radio next to the equipment. If the level indication fluctuates, slowly move the active radio away from the equipment until the fluctuation stops. This point will be used to determine the perimeter of the exclusion zone, or
  • Posting caution signs in the vicinity of the SFPI equipment, or
  • Including caution of radio usage in the vicinity of the SFPI equipment in FLEX Support Guideline procedures and/or other operating procedure(s).

Response

The physical proximity of the SFPLI enclosures to the Main Control Room spaces allows operators a short walk from the Control Room to the SFPLI enclosures such that communication devices are not necessary to relay SFP Wide Range Level Indication. However, because EMl/RFI testing of the SFPLIS was not performed after it was installed and no administrative barriers prohibiting use of radios adjacent to the transmitter or level indicator enclosures were put into place, the potential effects of EMl/RFI upon the instrumentation have not been dispositioned. Therefore, Condition Report 00111177 has been generated to pursue options for resolving possible EMl/RFI affects upon SFPLI operation. As part of actions for CR 00111177, Page 2 of 3

May 16, 2017 NRC COMPLIANCE LETTER ACCEPTANCE AND FINAL INTEGRATED PLAN RAls a review of the pre-installation EMl/RFI testing was performed. It was noted that WCGS has partially completed radio frequency testing. Section 9.7, Radio Frequency Test, of Reference 5 also performed a walkie-talkie test. The test started with the radio >10 feet from all three electronic devices, transmitter enclosure/cabinet, electronics cabinet display and launch plate.

The distance is decreased down to <1 foot with output current monitored for change. No changes were observed with the test results being acceptable. These results are documented on page 386 of 460 of Reference 5. No additional testing is deemed necessary given the results of the previous testing, and no additional exclusion areas are deemed necessary based on the SFPI instrumentation.

References:

1. Westinghouse Letter LTR-EQ-14-32, Spent Fuel Pool Instrumentation System -

Hardware Configuration for EMC Testing to Satisfy Performance Criteria B (WCNOC Correspondence No. 14-02131).

2. Westinghouse Presentation, SFPIS EMC Testing - Status and Summary, Suresh Channarasappa, February 4, 2014, (WCNOC Correspondence No. 14-02264).
3. *Design Change Package 014403, Spent Fuel Pool Instrumentation System.
4. Procedure Al 150-010, Wireless Communication Systems Usage and Requirements, Revision 4.
5. J-481A-00065, Westinghouse WNA-TR-03370-SAP, Spent Fuel Pool Instrumentation System Integrated Functional Test Report-Wolf Creek, Revision 0.
6. Condition Report 00111177.

Page 3 of 3

Enclosure V to RA 17-0067 NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 13-F (1 page)

May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls J

Issue No: 13-F Request:

(Peter Bamford, USNRC- 2128117 Email) DCP-014403 (ePorta/), Item #3 (IFCN 014403 (R-3c))

of Justification for Change (Page 3 of 4) states:

Westinghouse provided document J-481A-00041, Westinghouse document WNA-CN-00301-GEN, Rev.2. This SFPIS Channel Accuracy Calculation is the document used as design input to the Wolf Creek Total Plant Setpoint Document (TPSD). As stated above, the l&C technicians could not achieve the accuracy values stated in the documents. The issue involves the combined accuracy of the transmitter and probe assembly, which was far greater than originally believed.

Westinghouse provided the corrected accuracy of the level sensor components (transmitter + probe) by Letter dated October 13, 2014; LTR-SFP/S-14-136 RO, "Correction to WNA-CN-00301-GEN, Spent Fuel Pool Instrumentation System (SFP/S) Channel Accuracy Calculation" which increases the probe and transmitter uncertainties. Wolf Creek SFPIS Project Manager did not receive the change documentation until April 21, 2015. Wolf Creek will revise J-481A-00041 with letter L TR-SFPIS-14-136 RO (WC Correspondence No. 15-00466) as an attachment.

It is not clear whether the SFP/S accuracy stated in the SFPI Compliance Report (+/-3'?

represents the final value that accounts for the "increased probe and transmitter uncertainties" stated above. The licensee's final compliance letter addresses instrument accuracy; however it refers to supporting calculations dated in May and June of 2014, prior to the identification of the above cited change. Thus, it is not clear if the change (if any) to the instrument accuracy is properly captured in the compliance report. Please provide/confirm the SFPIS final accuracy.

Response

As noted in Interim Field Change Notice (IFCN) 014403 (R-3c) to Design Change Package (DCP) 014403 (Reference 1), Wolf Creek's review of Westinghouse WNA-CN-00301-GEN identified an error in the signal duplicator's contribution to the overall channel accuracy. Wolf Creek Nuclear Operating Corporation (WCNOC) Specification J-481A-00041 (Reference 2) was revised by adding Attachment A to the parent analysis in Westinghouse Document WNA-CN-00301-GEN, Spent Fuel Pool Instrumentation System Channel Accuracy Analysis, Revision 2. The revised WCNOC analysis re-calculated the overall channel accuracy and documented the final Spent Fuel Pool Instrumentation System (SFPIS) accuracy of+/- 3 inches.

References:

1. DCP 014403, Spent Fuel Pool Instrumentation System, Revision 3.
2. J-481A-00041, DCP 014403, Revision W03, Westinghouse WNA-CN-00301-GEN, Spent Fuel Pool Instrumentation System Channel Accuracy Analysis, Revision W03.

Page 1of1

Enclosure VI to RA 17-0067 NRC Compliance Letter Acceptance and Final Integrated Plan RAls Issue No.: 14-F (4 pages)

May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls Issue No: 14-F Request:

(Peter Bamford, USNRC- 2128117 Email) DCP-014403 (ePortal), Item #3 (IFCN 014403 (R-3c))

of Justification for Change (Page 3 of 4) states:

NE/ 12-02 specifies that testing and calibration of the instrumentation shall be consistent with the vendor recommendations or other documented basis. Please provide a listing of preventive maintenance (PM) tasks and associated frequencies for periodic testing, calibration, and component replacements. Also identify whether each of these PM tasks are consistent with the vendor recommendations.

Response

Following installation of FLEX Spent Fuel Pool (SFP) Wide Range Level instrumentation under Design Change Package (DCP) 014403, as part of the integrated functional test (IFT) plan per J-481A-0048, post-modification testing per Work Order (WO) 13-375528-055 was performed following design calibration J-481A-0049. Using Reference 4 as a basis, the following core work instructions (CWl's) were generated:

1. INC EC-0059, Spent Fuel Pool Level Loop EC LPL-0059, Revision 0.
2. INC EC-0060, Spent Fuel Pool Level Loop EC LPL-0060, Revision 0.

These instructions are consistent with Westinghouse calibration procedure and are the actions performed under Preventative Maintenance (PM) tasks that were established under WO 13-375528-026 for both channels. The two-point calibration check and the full calibration procedure are combined in the same WO instruction which allows the INC technician to use the same work order and proceed with the full calibration, if the associated SFP level instrument channel were to fail the calibration check. In addition to the calibration PMs, the following checks and PMs are in place:

  • Procedure SYS OQT-001A, Operations A Train Quarterly Tasks, Section 6.16, performs actions to dissolve boron crystals (boric acid plating) from various Spent Fuel Pool Components including the Spent Fuel Pool Level Instrumentation (SFPLI) (i.e., probe) as it hangs over the pool.
  • The operation's department performs daily checks on the SFPLI per procedure, CKL ZL-001, Auxiliary Building Reading Sheets, to verify they are operational. The checks compare the level variance between both FLEX SFP Wide Range Level instrument channels, and each FLEX SFPLI channel is checked against the actual SFP level. Discrepancies are recorded in the reading sheet and reported to Control Room. This results in generation of a Condition Report (CR) and an entry into the Equipment Out-Of-Service Log (EOL).
  • PMs are in place for ECLIT0059 and ECLIT0060 (Refer to PM File numbers 49809 and 49810, respectively) to replace the SFPIS Level Sensor Ele.ctronic Module in each channel on a six-year periodicity.

Table 1 provides a description of the various PMs, checks and tasks currently in place and discussed above.

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May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls

  • The replacement of the Level Sensor Electronics Module in each channel is consistent with a periodic replacement recommendation from J-481A-044, SFPIS Technical Manual, Section 7.
  • The two-point calibration and full calibration, and battery replacement are consistent with the Westinghouse recommendations J-481A-0049.
  • The periodic removal of boric acid plating from the cable and probe is consistent with periodic field cleaning recommendation from J-481A-044, SFPIS Technical Manual, Section 7.
  • The daily SFPIS Wide Range channel to channel and SPFIS Wide Range to Narrow Range variance is consi~tent with Westinghouse accuracy test checks in J-481A-0048.

Table 1 - SFPIS Related PMs, Checks, and Tasks PM /Procedures Scope Periodicity PM File numbers 49809 and Replace the Channel Level Sensor 6 years 49810 Electronics Module Two-point Calibration Check 18 months (1 Cycle) 16-415248-000 through 16-415251-000 3 cycles (4.5 years or Full Calibration 54 months) 16-415279-000 and 16-415280- Replace batteries (3 year battery life) 30 months (2.5 years) 000 Remove boric acid plating from SFP Procedure SYS OQT-001 A 3 month (Quarterly)

Components - SFPIS probe and cable

  • Chann~.toChannelCheck Procedure CKL ZL-001
  • SFPIS Wide Range to Narrow Range Daily Channel Check Additional reviews of the vendor technical manual and vendor testing plan were performed.

J-481A-044. SFPIS Technical Manual:

Review of Section 5, Periodic Testing and Calibration, identified the following recommended tests that are encompassed in the current CWls for SFPIS Channel Calibration PMs:

  • Channel Calibration
  • Level transmitter scaling
  • Coaxial Cable testing NOTE: The Resistance Temperature Detector (RTD) Calibration listed in J-481A-044 Section 5 is not applicable to Wolf Creek.

Review of WCGS Specification J-481A-044 Section 7, "System Maintenance," identified vendor recommendations for periodic replacement of other SFPIS components in addition the Level Sensor Electronics Module. The replacement recommendations were reviewed with consideration of the daily channel checks that would reveal a condition. The condition would result in corrective actions to troubleshoot and identify a weak or degraded component that would be subject to replacement. Therefore, the bulk of the periodic component replacement recommendations were not carried forward but would be implemented on an as-needed basis.

Page 2of4

May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls J-481A-048. SFPIS Standard Product Integrated Functional Test Plan:

Review of Section 3, Features To Be Tested, identified additional testing of SFPIS features and design that was not included in the PM Program for the SFPIS:

  • 120 Voltage Alternating Current (VAC) line power (+/-10%) - This test was performed satisfactorily during the IFT but was not considered necessary to continue as the plant instrument bus power is continuously monitored and operations would be alerted to a condition if it exceeded +/-10%.
  • 24 Voltage Direct Current (VDC) Power Supply (+/-10%) - This test was performed satisfactorily during the IFT but was not carried forward into the current CWls. This test will be added to the current PM program. CR 00111778 and CR 00111779 have been generated to track the addition of this test.
  • Loss of AC Power Swap Over Feature - This test was performed satisfactorily during the IFT but was not carried forward into the current CWls. This critical design feature for the SFPIS will be added to the current PM program. The scopes of CR 00111778 and CR 00111779 include adding this test to each channel PM.
  • Backup battery capacity (~ 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />) - This test was performed satisfactorily during the IFT verifying batteries have sufficient capacity to power the SFPIS for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. This test was not carried forward into the current CW ls. The justification is below:

o The basis for not performing a capacity test is that we are replacing a 3-year battery every 2.5 years with a new battery. The battery's service life of 3 years is 70-80% of the batteries design life.

o One of the objectives of the level instrument is to provide backup power from the battery for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> upon the loss of normal power. To meet this objective, the designer selects the capacity of the battery to confidently provide this much power over its service life, 3 years in our case.

o The vendor rates the battery at 26 amp-hours, and it is part number PS20035H05, model 2320429. When replacing a component, the part and model numbers are used unless a design evaluation allows something else to be used.

o Westinghouse consumption Calculation J-481A-00040 with IEEE margins on battery model 2320429 reflects that 0.244 amps are taken from the 26 amp-hour battery making it capable of providing its function for 26 amp-hours/0.244 amps = 106.56 hours6.481481e-4 days <br />0.0156 hours <br />9.259259e-5 weeks <br />2.1308e-5 months <br />, when only 72 are needed.

o Therefore, replacing the 3-year battery every 2.5 years utilizes only a portion of the full service life of the battery and maintains a large margin of battery life. There is reasonable assurance that the function of providing back up power from the battery for the level instrument for 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, if needed, is ensured.

Summary: The WCGS SFPIS PM program currently incorporates those tests that encompass the scope of the recommendations from Westinghouse Technical Manual, with justified exceptions. The additional two tests, 24 VDC power supply and Loss of AC power automatic transfer function, will be added to existing SFPIS PM Program. CR 00111778 for EC-Ll-0059 and CR 00111779 for EC-Ll-060 were initiated to track adding these tests to each channel testing program.

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May 16, 2017 NRC COMPLIANCE REVIEW AND FINAL INTEGRATED PLAN RAls Condition Reports 00111778 and 00111779 were closed to WO 17-424921 for EC-Ll-059 and WO 17-424919 for EC-Ll-060, to evaluate the enhancement to the calibration instructions to add two tests: 1) verifying the 24 VDC Power Supply, and 2) verify the automatic power transfer feature. The Core Work Instructions INC EC-0059 and INC EC-0060 were revised on April 13, 2017, to add these two tests into the periodic calibration in each SFPLI channel completing the action required of WO 17-424921 and WO 17-424919.

References:

1. J-481A-040, SFPIS Power Consumption Calculation associated with CP 014403, Revision W01, (Westinghouse WNA-CN-00300-GEN, Revision 0)
2. J-481A-0044, SFPIS Technical Manual, associated with CP 014403, Revision W01, (Westinghouse WNA-G0-00127-GEN, Revision 3).
3. J-481A-00048, SFPIS Standard Product Integrated Functional Test Plan, associated with CP 014403, Revision W01 (Westinghouse WNA-TP-00189-GEN, Revision 2).
4. J-481A-00049, SFPIS Calibration Procedure, associated with CP 014403, Revision W0.1 (Westinghouse WNA-TP-04709-GEN, Revision 4).
5. Core Work Instructions INC EC-0059, Spent Fuel Pool Level Loop EC LPL-0059, Revision 0.
6. Core Work Instructions INC EC-0060, Spent Fuel Pool Level Loop EC LPL-0060, Revision 0.
7. Work Order 13-375528-055, Post Modification Testing for EC-Ll-0059 and EC-Ll-0060.
8. Work Order 13-375528-026, Preventative Maintenance Change Request to Establish PMs for Fukushima Spent Fuel Pool Level Instrumentation.
9. Procedure CKL ZL-001, Auxiliary Building Reading Sheets, Revision 98A.
10. Procedure SYS OQT-001A, Operations A Train Quarterly Tasks, Revision 14.
11. PM File number 49809 for ECLIT0059.
12. PM File Number 49810 for ECLIT0060.
13. Condition Report 00111778 for EC-Ll-0059.
14. Condition Report 00111779 for EC-Ll-0060.
15. Work Order 17-424921-000 for EC-Ll-0059.
16. Work Order 17-424919-000 for EC-Ll-0060.

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