ML111530439

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(Redacted) Request for Additional Information from Nrr/De/Emcb Steam Dryer, Round 2, Amendment Request for Extended Power Uprate to Increase the Maximum Reactor Core Power Operating Limit from 3898 to 4408 Mwt
ML111530439
Person / Time
Site: Grand Gulf Entergy icon.png
Issue date: 06/06/2011
From: Wang A
Plant Licensing Branch IV
To:
Entergy Operations
Wang, A B, NRR/DORL/LPLIV, 415-1445
Shared Package
ML111530429 List:
References
TAC ME4679
Download: ML111530439 (4)


Text

OPPICIAL use ONLY ~ PROPRieTARY INFORMATION UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 June 6, 2011 Vice President, Operations Entergy Operations, Inc.

Grand Gulf Nuclear Station P.O. Box 756 Port Gibson, MS 39150

SUBJECT:

GRAND GULF NUCLEAR STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING EXTENDED POWER UPRATE APPLICATION LICENSE AMENDMENT REQUEST (TAC NO. ME4679)

Dear Sir or Madam:

By letter dated September 8,2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102660409). Entergy Operations, Inc. (Entergy, the licensee),

submitted a license amendment request for the Grand Gulf Nuclear Station, Unit 1 (GGNS).

The proposed amendment requests an increase in the maximum steady-state power level at GGNS from 3898 megawatts thermal (MWt) to 4408 MWt. This represents an approximate 13 percent increase above the current licensed thermal power or an approximate 15 percent increase above the original licensed thermal power.

By letter dated March 30, 2011 (ADAMS Accession No. ML110900275), Entergy submitted responses to the U.S. Nuclear Regulatory Commission (NRC) staffs request for additional information (RAI) dated March 2.2011 (ADAMS Accession No. ML110550475), for GGNS. The NRC staff has determined that additional information is needed in order for the staff to complete its review of this amendment request. The enclosed RAI was discussed with Mr. Jerry Burford of your staff on June 1, 2011, and it was agreed that a response would be provided within 30 days of receipt of this letter. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1445 or via e-mail at Alan.Wang@nrc.gov.

Sincerely,

~ v0 tt_.~~~/

Alan B. Wang, projec~anager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-416

Enclosure:

As stated cc w/non-proprietary encl: Distribution via Listserv NOTICE: The Enclosure to this letter contains Proprietary Information. Upon separation from the Enclosure, this letter is DECONTROLLED.

OFFICIAL USE ONLY PROPRIETARY INFORMATION ~,i"vJ

OFFICIAL USE ONLY* PROPRIETARY' INFORMATION REQUEST FOR ADDITIONAL INFORMATION GRAND GULF NUCLEAR STATION, UNIT NO.1 EXTENDED POWER UPRATE LICENSE AMENDMENT REQUEST ENTERGY OPERATIONS, INC.

DOCKET NO. 50-416 By letter dated September 8, 2010 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML102660409), Entergy Operations, Inc. (Entergy, the licensee),

submitted a license amendment request for the Grand Gulf Nuclear Station, Unit 1 (GGNS).

The proposed amendment requests an increase in the maximum steady*state power level at GGNS from 3898 megawatts thermal (MWt) to 4408 MWt. This represents an approximate 13 percent increase above the current licensed thermal power or an approximate 15 percent increase above the original licensed thermal power.

By letter dated March 30,2011 (ADAMS Accession No. ML110900275), Entergy submitted responses to the U.S. Nuclear Regulatory Commission (NRC) staff's request for additional information (RAI) dated March 2, 2011 (ADAMS Accession No. ML110550475), for GGNS.

Based on its review of the licensee's RAI responses, the NRC staff has identified areas in your responses for which additional information is required. Please note that numbering of the additional RAls is consistent with the March 30, 2011, request. The NRC staff has determined that there is proprietary information contained in this request and we have made the document proprietary.

3) In response to RAI 3, the licensee stated that the steam dryer welds are fabricated according to the rules of the American SOCiety of Mechanical Engineers Boiler and Pressure Code (ASME Code),Section III, Subsection NG, which includes visual and liquid penetrant examination of the root and final passes of the welds. However, these examinations cannot detect the flaws that are not penetrating the surface of the root pass or final pass. The licensee further stated that the maximum thickness of the root pass is -3/16 inch. It is likely that a flaw as large as 3/16-inch can be present and remain undetected. Please evaluate the potential growth of a 3/16-inch flaw in a weld that is subjected to the maximum alternating stress intensity at extended power uprate (EPU).
9) In response to RAI 9, the licensee stated that four safety relief valves (SRVs) Will be instrumented and monitored to maintain acceleration levels within acceptance limits.

Please explain how the licensee will ensure that the valve with the maximum vibration level will be among those that are selected for vibration monitoring. Also, please provide the plan for mitigating excessive vibration (should it occur) and/or replacing valves with designs that are more resistant to the vibrations.

12) In response to RA112, the licensee explained that it evaluated stresses a t _

l1li to determine the maximum stress at the fillet weld. The licensee further stated Enclosure OFFICIAL USE ONLY PROPRIETARY INFORMATION

OFFICIAL USE ONLY PROPRIETARY INFORMATION \\~0

-2

13) Regarding RA113:

(a) vane assem loading and generate loose parts. Please provide information on the magnitude of the fundamental frequency of the vane assembly substructure.

(b) In response to RAI 13, the licensee showed that for the instrumented boili water reactor 4 steam

21) As stated in the license amendment request, the licensee is replacing the existing steam dryer with a new steam dryer. Another licensee (PPL Susquehanna LLC) also replaced its steam dryers for both units of Susquehanna Steam Electric Station for EPU operation. Based on recent operating experience, the NRC staff was informed of steam dryer cracking that was discovered in both units of the newly replaced steam dryers (RSD) during the first refueling outage after the EPU operation at Susquehanna. Three cracks were observed in the dryer skirt tee in Susquehanna Unit 1, and cracks were observed in the dryer skirt panel and at the bottom of the upper support ring in Susquehanna Unit 2. In light of the cracking observed in the RSDs, please describe the measures taken or planned to be taken during fabrication, installation, quality control, pre-installation inspection enhancements, or any design improvements to ensure that similar cracking of the new replacement steam dryers would not occur during EPU operation at GGNS.

OFFICIAL USE ONLY PROPRIETARY INFORMATION

OFFICIAL USE ONLY PROPRIETARY INFORMATION June 6,2011 Vice President, Operations Entergy Operations, Inc.

Grand Gulf Nuclear Station P.O. Box 756 Port Gibson, MS 39150

SUBJECT:

GRAND GULF NUCLEAR STATION, UNIT 1 - REQUEST FOR ADDITIONAL INFORMATION REGARDING EXTENDED POWER UPRATE APPLICATION LICENSE AMENDMENT REQUEST (TAC NO. ME4679)

Dear Sir or Madam:

By letter dated March 30, 2011 (ADAMS Accession No. ML110900275), Entergy submitted responses to the U.S. Nuclear Regulatory Commission (NRC) staff's request for additional information (RAI) dated March 2, 2011 (ADAMS Accession No. ML110550475). for GGNS. The NRC staff has determined that additional information is needed in order for the staff to complete its review of this amendment request. The enclosed RAI was discussed with Mr. Jerry Burford of your staff on June 1, 2011, and it was agreed that a response would be provided within 30 days of receipt of this letter. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1445 or via e-mail at Alan.Wang@nrc.gov.

By letter dated March 30, 2011 (ADAMS Accession No. ML110900586), Entergy submitted responses to the U.S. Nuclear Regulatory Commission (NRC) staff's request for additional information (RAI) dated March 2, 2011 (ADAMS Accession No. ML110550475), for GGNS. The NRC staff has determined that additional information is needed in order for the staff to complete its review of this amendment request. The enclosed RAI was discussed with Mr. Jerry Burford of your staff on June 1, 2011, and it was agreed that a response would be provided within 30 days of receipt of this letter. If circumstances result in the need to revise the requested response date, please contact me at (301) 415-1445 orvia e-mail at Alan.Wang@nrc.gov.

Sincerely, IRA!

Alan B. Wang, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-416

Enclosure:

As stated cc w/non-proprietary end: Distribution via Listserv NOTICE: The Enclosure to this letter contains Proprietary Information. Upon separation from the Enclosure, this letter is DECONTROLLED.

DISTRIBUTION:

NON-PUBLIC RidsNrrDeEmcb Resource RidsNrrPMGrandGulf Resource LPLIV r/f RidsNrrDorlLpl4 Resource RidsRgn4MailCenter Resource RidsAcrsAcnw_MailCTR Resource RidsNrrLAJBurkhardt Resource CBasavaraju. NRR/DE/EMCB ADAMS Accession Nos'.. Package ML111530429' Proprietary - ML111530436' Non-proprietary ML111530439 j , , ,

iI OFFICE NRR/DORLlLPL4/PM NRR/DORLlLPL4/LA NRR/DORLlLPL4/BC NRR/DORLlLPL4/PM I NAME AWang JBurkhardt MMarkley AWang DATE 6/6/11 6/3/11 6/6/11 6/6/11 j

OFFICIAL AGENCY RECORD OFFICIAL USE ONLY PROPRIETARY INFORMATION