ML24143A111

Draft 2nd Round Request for RAIs Concerning LAR to Modify LCO for TS 3.5.2, LCO for TS 3.6.5, and Surveillance Requirements 3.5.1.2 and 3.5.2.2 for TS 3.5.1 and TS 3.5.2

ML24143A111
Person / Time
Site:	Palo Verde
Issue date:	05/20/2024
From:	William Orders Plant Licensing Branch IV
To:	Dilorenzo M Arizona Public Service Co
Orders, William
References
Download: ML24143A111 (1)

Text

From: William Orders To: Michael.Dilorenzo@aps.com Bcc: William Orders

Subject:

Request for Additional Information concerning license amendment request (LAR) to modify Limiting Condition for Operation (LCO) for Technical Specification (TS) 3.5.2, "Safety Injection Tanks (SIT) - Shutdown," LCO for TS 3.6.5, Date: Monday, May 20, 2024 2:59:00 PM

Subject Additional Information (RAIs) concerning license amendment request (LAR) to modify Limiting Condition for Operation (LCO) for Technical Specification (TS) 3.5.2, "Safety Injection Tanks (SIT) - Shutdown," LCO for TS 3.6.5, "Containment Air Temperature," and Surveillance Requirements (SRs) 3.5.1.2 and 3.5.2.2 for TS 3.5.1, "Safety Injection Tanks (SITs) -

Operating," and TS 3.5.2, respectively.

Mr. Dilorenzo,

By application dated June 29, 2023, as supplemented by letter dated March 6, 2024, (Agencywide Documents Access and Management System (ADAMS) Accession Nos.

ML23180A222 (Reference 1) and ML24066A047 (Reference 2) respectively, Arizona Public Service Company (APS) (APS, the licensee) submitted a license amendment request (LAR) for Palo Verde Nuclear Generating Station, Units 1, 2, and 3 (PVNGS) proposing to modify Limiting Condition for Operation (LCO) for Technical Specification (TS) 3.5.2, Safety Injection Tanks (SITs) - Shutdown, LCO for TS 3.6.5, Containment Air Temperature, and Surveillance Requirements (SRs) 3.5.1.2 and 3.5.2.2 for TS 3.5.1, Safety Injection Tanks (SITs) - Operating, and TS 3.5.2, respectively.

After reviewing the enclosures of APSs letters dated June 29, 2023, and March 6, 2024, and in consideration of the information exchanged during clarification call between the NRC and APS staff held on May 15, 2024, the NRC staff requests responses to the requests for additional information (RAIs) given below.

The principal design criteria for PVNGS were developed in consideration of the seventy General Design Criteria (GDC) for Nuclear Power Plant Construction Permits proposed by the AEC in a proposed rulemaking published for 10CFR Part 50 in the Federal Register of July 11, 1967. The principal design criteria from the PVNGS Updated Final Safety Analysis Report (UFSAR) Section 3.1 that is applicable is referred to in the regulatory basis for the RAIs given below.

Regulatory Basis:

The following 10 CFR Part 50, Appendix A, General Design Criteria (GDC) are applicable:

• GDC 16, Containment design, as it relates to providing a reactor containment and associated systems to establish an essentially leak-tight barrier against the uncontrolled release of radioactivity to the environment and to assure that the containment design conditions important to safety are not exceeded for as long as postulated accident conditions require.

• GDC 38, Containment heat removal, as it relates to providing a system to remove heat from the reactor containment whose safety function is to reduce rapidly, consistent with the functioning of other associated systems, the containment pressure and temperature following any loss-of-coolant accident and maintain them at acceptably low levels.

• GDC 50, Containment design basis, as it relates to designing the reactor containment structure, including access openings, penetrations, and the containment heat removal system so that the containment structure and its internal compartments can accommodate, without exceeding the design leakage rate and with sufficient margin, the calculated pressure and temperature conditions resulting from any loss-of-coolant accident.

RAI:

The licensee proposes to change TS LCO 3.6.5 from its existing value of 117°F to the design analytical value of 120°F. To justify, in the letter dated March 6, 2024 (Reference 2), the licensee stated:

PVNGS Technical Specifications contain both the LCO limit and Surveillance Requirement (SR) which is implemented by the Control Room Operators in accordance with surveillance testing (ST). The ST procedures reflect the total loop uncertainty calculations which specifies the indicated value to provide reasonable assurance that the analytical limit is not exceeded.

Therefore, the TS value of 120°F does not account for instrument uncertainty and instead it is controlled within the licensee-controlled TS Bases and surveillance procedures, pursuant to 10 CFR 50.59.

Describe any effects on the safety analyses from the TS value change from 117°F to 120°F and the operator actions taken if the surveillance test containment temperature limit is exceeded.

1.0 REFERENCES

1. Letter from APS to NRC, Palo Verde Nuclear Generating Station Units 1, 2, and 3, Docket Nos. STN 50-528, 50-529, and 50-530, Renewed Operating License Number NPF-41, NPF-51, and NPF-74 Application to Revise Technical Specifications (TS) 3.5.1, Safety Injection Tanks (SITs) - Operating, TS 3.5.2, Safety Injection Tanks (SITs) - Shutdown, and TS 3.6.5, Containment Air Temperature. June 29, 2023, ADAMS Accession No. ML23180A222

2. Letter from APS to NRC, Palo Verde Nuclear Generating Station Units 1, 2, and 3, Docket Nos. STN 50-528, 50-529, and 50-530, Renewed Operating License Number NPF-41, NPF-51, and NPF-74, Response to Request for Additional Information to Revise Technical Specifications (TS) 3.5.1, Safety Injection Tanks (SITs) - Operating, TS 3.5.2, Safety Injection Tanks (SITs) - Shutdown, and TS 3.6.5, Containment Air Temperature, March 6, 2024, ADAMS Accession No. ML24066A047

3. PVNGS UFSAR, Revision 22, ADAMS Accession No. ML23181A159

This RAI was provided to on May 17, 2024 as draft, to allow you the opportunity to request a clarification call. By email on May 20, 2024, you indicated that you understand the RAI and do not request a clarification call. Therefore, please respond to this RAI within 30 days of todays date.

William Orders (301) 415-3329