View source for CNL-16-178, Response to Request for Additional Information (RAI) Regarding Application to Modify Technical Specifications Regarding Diesel Generator Steady State Frequency (SQN-TS-14-02)

{{Adams
| number = ML16362A209
| issue date = 12/23/2016
| title = Response to Request for Additional Information (RAI) Regarding Application to Modify Technical Specifications Regarding Diesel Generator Steady State Frequency (SQN-TS-14-02)
| author name = Shea J
| author affiliation = Tennessee Valley Authority
| addressee name = 
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000327, 05000328
| license number = DPR-077, DPR-079
| contact person = 
| case reference number = CAC MF7762, CAC MF7763, CNL-16-178
| document type = Response to Request for Additional Information (RAI), Technical Specifications
| page count = 4
| project = CAC:MF7762, CAC:MF7763
| stage = Response to RAI
}}

=Text=
{{#Wiki_filter:Tennessee Valley Authority, 1101 Market Street, Chattanooga, Tennessee 37402 CNL-16-178 December 23, 2016 10 CFR 50.90 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 Sequoyah Nuclear Plant, Units 1 and 2 Renewed Facility Operating License Nos. DPR-77 and DPR-79 NRC Docket Nos. 50-327 and 328

==Subject:==
Response to Request For Additional Information (RAI) regarding Application to Modify Sequoyah Nuclear Plant, Units 1 and 2 Technical Specifications Regarding Diesel Generator Steady State Frequency (SQN-TS-14-02) (CAC Nos. MF7762 and MF7763)

==References:==
: 1. Letter from TVA to NRC, CNL-16-001, "Sequoyah Nuclear Plant, Units 1 and 2, Application to Modify Sequoyah Nuclear Plant, Units 1 and 2 Technical Specifications Regarding Diesel Generator Steady State Frequency (SQN-TS-14-02)," dated May 26, 2016
: 2. Email from NRC to TVA, RAI for SQN LAR to Modify Technical Specifications Regarding Diesel Generator Steady State Frequency (CAC Nos. MF7762 and MF7763), dated October 31, 2016 By the Reference 1 letter, Tennessee Valley Authority (TVA) submitted a license amendment request (LAR) to amend the Sequoyah Nuclear Plant (SQN), Units 1 and 2 Technical Specifications (TS) by modifying the acceptance criteria for the diesel generator (DG) steady state frequency range provided in TS Surveillance Requirements (SRs) 3.8.1.2, 3.8.1.7, 3.8.1.9, 3.8.1.11, 3.8.1.12, 3.8.1.15, and 3.8.1.18. In Reference 2, the NRC provided a Request for Additional Information (RAI) related to the proposed change to TS 3.7.8. The enclosure to this letter provides the response to the RAI included in the Reference 2 email.

U.S. Nuclear Regulatory Commission CNL-16-178 Page 2 December 23, 2016 TVA has reviewed the information supporting a finding of no significant hazards consideration and the environmental consideration provided to the NRC in the Reference 1 letter. The supplemental information provided in this submittal does not affect the bases for concluding that the proposed license amendment does not involve a significant hazards consideration. In addition, the supplemental information in this submittal does not affect the bases for concluding that neither an environmental impact statement nor an environmental assessment needs to be prepared in connection with the proposed license amendment.
There are no new regulatory commitments associated with this submittal. If there are any questions or if additional information is needed, please contact Mr. Edward D. Schrull at (423) 751-3850.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 23th day of December 2016.
Respectfully, J. W. Shea Vice President, Nuclear Licensing

==Enclosure:==
Response to NRC Request for Additional Information cc: (w/ Enclosure)
NRC Regional Administrator - Reg ion II NRC Senior Resident Inspector - Sequoyah Nuclear Plant NRC SQN Project Manager

ENCLOSURE Response to NRC Request for Additional Information REQUEST FOR ADDITIONAL INFORMATION (RAI)
TENNESSEE VALLE AUTHORITY SEQUOYAH NUCLEAR PLANT UNITS 1 AND 2 LICENSE AMENDMENT REQUEST SQN-TS-14-02 DOCKET NUMBERS 50-327 AND 50-328 (TAC NOS. MF7762 AND MF7763)

==Reference:==

Letter from J. W. Shea of the Tennessee Valley Authority to NRC, Application to Modify Sequoyah Nuclear Plant, Units 1 and 2 Technical Specifications Regarding Diesel Generator Steady State Frequency (SQN-TS-14-02), dated May 26, 2016 (Agencywide Document Access and Management System (ADAMS) Accession Number ML16148A175).
RAI EPNB-1 The ASME OM Code stroke-timing test for motor-operated valves is performed to meet the inservice testing requirements of 10 CFR 50.55a. Please discuss the impact of pump discharge pressure/differential pressure on motor-operated valves as a result of a higher than nominal diesel generator frequency.
TVA Response:
The pump affinity laws can be applied using the following formula to determine pressure changes due to an increase in diesel generator frequency:
H2 = H1 / (N1/N2)2
: where, H2 = Changed pump pressure due to DG frequency variation H1 = Nominal pump pressure N2 = Changed pump speed due to DG frequency variation N1 = Nominal pump speed For the 60.2 frequency:
H2 = H1 / (60/60.2)2 = H1/(0.993) = H1
* 1.007              (0.7% Increase)
The resulting increase in total pump pressure due to increasing the DG frequency is 0.7%.
All active safety related motor operated valves (MOVs) were evaluated to determined if a 0.7%
increase in pump discharge pressure would affect the ability of each MOV to perform its design function. Differential pressure for the MOVs was determined based on the systems pump shut off head or the expected pump pressure at a nominal flow. The change in pressure during a diesel generator over frequency condition is minimal (0.7%) and considered non-significant in comparison to the conservative approach taken to develop the MOV differential pressures and the development of the MOV calculations. Therefore, TVA concludes that all MOVs will perform Page E-1 of 2

their design function and the minimal MOV differential pressure increase due to diesel generator over frequency will not affect the results of the calculations nor the setup of the MOVs in the field.
RAI EPNB-2 Section 3.2.3.1.1 of the LAR states, Therefore, a 0.2 Hz change in DG frequency will change pump flow by +/-0.33%. Section 3.2.3.2 of the LAR states The flow change resulting from the DG frequency variation is limited to +/-0.35%. Confirm which value is correct.
TVA Response:
Section 3.2.3.1.1 provides the calculation of the +/-0.33% change in flow. Section 3.2.3.2 incorrectly states this to be +/-0.35%. The correct value for the calculated change in flow in section 3.2.3.2 is +/-0.33%.
Page E-2 of 2}}