ML16357A451

November 21, 2016 Summary Report for Audit in Support of Review of a License Amendment to Revise Technical Specifications Fuel Storage Requirements at Duane Arnold Energy Center

ML16357A451
Person / Time
Site:	Duane Arnold
Issue date:	01/18/2017
From:	Mahesh Chawla Plant Licensing Branch III
To:	Catron S Nextera Energy
Chawla M, NRR-DORL 415-8371
References
CAC MF7486
Download: ML16357A451 (5)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 January 18, 2017 Mr. Steve Catron Licensing Manager NextEra Energy 15430 Endeavor Dr.

Jupiter, FL 33478

SUMMARY

REPORT FOR THE NOVEMBER 21, 2016 AUDIT IN SUPPORT OF THE REVIEW OF A LICENSE AMENDMENT TO REVISE TECHNICAL SPECIFICATIONS FUEL STORAGE REQUIREMENTS AT DUANE ARNOLD ENERGY CENTER (CAC NO. MF7486)

Dear Mr. Catron:

By letter dated March 15, 2016 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML16077A234), NextEra Energy Duane Arnold submitted a License Amendment Request (LAR) for the Duane Arnold Energy Center. The proposed amendment would revise the spent fuel storage requirements in Technical Specification 4.3.1, "Criticality,"

and TS 4.3.3, "Capacity," and adds a new requirement in TS 5.5, "Programs and Manuals," for a Spent Fuel Pool (SFP) neutron absorber monitoring program.

The U.S. Nuclear Regulatory Commission (NRC) staff reviewed the nuclear criticality safety analysis that was included with the LAR to demonstrate that NRC requirements associated with SFP subcriticality will be met. The staff sent draft Requests for Additional Information (RAls) to the licensee via email on September 21, 2016 (ADAMS Accession No. ML16267A064), to address potential non-conservatisms in the analysis. Subsequent teleconferences were conducted with the licensee on September 26 and October 4, 2016, to clarify the RAls and determine the best approach for a timely resolutions of the issues identified in the RAls. The staff recognized that the nuclear criticality safety analysis demonstrated a significant amount of margin to the regulatory limit. Therefore, some of the RAls may not be necessary if the licensee is able to provide adequate documentation to address the missing information being requested by the rest of the RAls. An audit was determined to be the most efficient approach to allow the NRC staff to verify that adequate documentation would be provided to allow the staff to complete the review and determine if the responses are acceptable, or if the licensee would need to provide the additional information being requested in other RAls. The staff noted that upon completion of the audit, the draft RAls would be revised as necessary and issued as final, and the licensee would be expected to provide the needed information on the docket.

On November 14, 2016, the audit plan was e-mailed to the licensee (ADAMS Accession No. ML16327A093). The NRC staff conducted the audit on November 21, 2016, at the NextEra office in Jupiter, Florida. The results of the audit were used by the NRC staff to finalize and transmit RAls on November 28, 2016 (ADAMS Accession No. ML16333A462).

The audit summary report is provided as an enclosure to this letter.

S. Catron If you have any questions, please contact me at (301) 415-8371 or Mahesh.Chawla@nrc.gov.

Sincerely, Mahesh Chawla, Project Manager Plant Licensing Branch 111 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Enclosures:

Summary Report for Audit cc w/encls: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 AUDIT

SUMMARY

REPORT FOR DUANE ARNOLD ENERGY CENTER, REGARDING DRAFT REQUEST FOR ADDITIONAL INFORMATION RESPONSES RELATING TO THE LICENSE AMENDMENT TO REVISE TECHNICAL SPECIFICATIONS FUEL STORAGE REQUIREMENTS DUANE ARNOLD ENERGY CENTER DOCKET NO. 50-331 CAC NO. MF7486

1. INTRODUCTION By letter dated March 15, 2016 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML16077A234), NextEra Energy Duane Arnold, the licensee, submitted a license amendment request (LAR) for the Duane Arnold Energy Center (DAEC).

The proposed amendment would revise the spent fuel storage requirements in TS 4.3.1, "Fuel Storage, Criticality," and TS 4.3.3, "Fuel Storage, Capacity," to reflect an updated current licensing basis for the facility, as well as add a new requirement in TS 5.5, "Programs and Manuals," for a spent fuel pool (SFP) neutron absorber monitoring program.

The U.S. Nuclear Regulatory Commission (NRC) staff reviewed a nuclear criticality safety analysis that was included with the LAR to demonstrate that NRC requirements associated with SFP subcriticality will be met. The staff sent draft requests for additional information (RAls) to the licensee via email on September 21, 2016 (ADAMS Accession No. ML16267A064), to address potential non-conservatisms in the analysis. Subsequent teleconferences were conducted with the licensee on September 26, and October 4, 2016, to clarify the RAls and determine the best approach for a timely resolutions of the issues identified in the RAls. The staff recognized that the nuclear criticality safety analysis demonstrated a significant amount of margin to the regulatory limit. Therefore, some of the RAls may not be necessary, if the licensee is able to provide adequate documentation to address the missing information being requested by the rest of the RAls.

Since this subset of RAls must be addressed to allow the staff to base a safety finding without requiring further information, the licensee committed to developing draft RAI responses and to support an audit. The purpose of this audit was to allow the staff to review the licensee's documentation, and determine if the documentation will be adequate for review purposes. This was determined to be the most efficient approach toward a timely resolution of this LAR review, since the staff will have an opportunity to determine if the additional RAls will be necessary and no unnecessary burden will be imposed by requiring the licensee to address issues that are not likely to be important to a safety determination. An audit plan was electronically transmitted on November 14, 2016 (ADAMS Accession No. ML16327A093), which included the aforementioned subset of RAls.

Enclosure

This technical audit was performed consistent with NRC Office of Nuclear Reactor Regulation Office Instruction LIC-111, "Regulatory Audits," dated December 29, 2008 (ADAMS Accession No. ML082900195). The audit supports a timely resolution of all outstanding issues with the SFP nuclear criticality analysis report, allowing the staff to make a safety determination on the associated LAR.

2. AUDIT ACTIVITIES AND OBSERVATIONS The area of focus for the regulatory audit was the licensee's documentation related to the draft RAls listed in the audit plan. The intent of this review was to determine if: (1) any RAls needed to be rewritten to clarify the information being requested, and (2) if additional RAls needed to be submitted in order to collect sufficient documentation to complete the staff review.

In addition, the licensee provided a copy of the base MCNP (Monte Carlo N-Particle code) input deck used to perform the SFP nuclear criticality safety. In particular, the input deck provided details on the exact nature of the initial source distribution, modeling geometry, compositions, and calculational options.

3. CONCLUSIONS During this audit, the staff did not make any regulatory decisions regarding the proposed license amendment. However, the staff was able to determine the information that the licensee planned to provide in response to a subset of the draft RAls via email on September 21, 2016 (ADAMS Accession No. ML16267A064) would be sufficient to allow the staff to continue their review of the LAR in the office. As a result, upon completion of this audit, the staff finalized and transmitted the RAls (ADAMS Accession No. ML16333A462) as listed in the audit plan. The final RAI responses are expected to be delivered by the licensee by the end of December 2016.

The staff also confirmed that the calculational inputs used for the licensee's criticality calculations conformed to the staff's understanding of the licensee's criticality analysis model.

4. AUDIT PARTICIPANTS Scott Krepel (NRC)

Mahesh Chawla (NRC)

Steve Catron (NextEra Energy)

Emilio Fuentes (NextEra Energy)

Principal Contributor: Scott Krepel, NRR/DSS/SNPB

S. Catron If you have any questions, please contact me at (301) 415-8371 or Mahesh.Chawla@nrc.gov.

Sincerely, IRA/

Mahesh Chawla, Project Manager Plant Licensing Branch Ill Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Enclosures:

Summary Report for Audit cc w/encls: Distribution via Listserv DISTRIBUTION:

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