ML070530685
| ML070530685 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 03/05/2007 |
| From: | Farideh Saba NRC/NRR/ADRO/DORL/LPLIV |
| To: | Mitchell T Entergy Operations |
| Saba F, NRR/DORL/LPL4, 301-415-1447 | |
| References | |
| TAC MB9770, TAC MB9771 | |
| Download: ML070530685 (5) | |
Text
March 5, 2007 Mr. Timothy G. Mitchell Vice President, Operations Arkansas Nuclear One Entergy Operations, Inc.
1448 SR 333 Russellville, AR 72802
SUBJECT:
ARKANSAS NUCLEAR ONE, UNITS 1 AND 2 - NRC RECEIPT OF RESPONSE TO GENERIC LETTER 2003-01, CONTROL ROOM HABITABILITY (TAC NOS. MB9770 AND MB9771)
Dear Mr. Mitchell:
The Nuclear Regulatory Commission (NRC) acknowledges the receipt of the Entergy Operations, Inc. (Entergy), responses to Generic Letter (GL) 2003-01, Control Room Habitability, dated August 28, 2003 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML032450205), June 24, 2004 (ADAMS Accession No. ML041800409), May 2, 2006 (ADAMS Accession No. ML061430257), and February 14, 2007 (ADAMS Accession No. ML070610449). This letter provides a status of Entergys response and describes any additional information that may be required to consider your response to GL 2003-01 complete.
GL 2003-01 requested that the licensees confirm that the control room meets its design bases (e.g., General Design Criteria (GDC) 1, 3, 4, 5, and 19, draft GDC, or principal design criteria) with special attention to the following:
(1)
GL 2003-01, Item 1a: Determination of the most limiting unfiltered and/or filtered inleakage into the control room and comparison to values used in the design bases for meeting control room operator dose limits from accidents.
(2)
GL 2003-01, Item 1b: Determination that the most limiting unfiltered inleakage is incorporated into the hazardous chemical assessments.
(3)
GL 2003-01, Item 1b: Determination that reactor control capability is maintained in the control room or at the alternate shutdown location in the event of smoke.
(4)
GL 2003-01, Item 2: Provide information on any compensatory measures in use to demonstrate control room habitability, and plans to retire them.
T. Mitchell Entergy reported the results of ASTM E741 (American Society for Testing Materials, Standard Test Method for Determining Air Change in a Single Zone by Means of a Tracer Gas Dilution) tracer gas tests of the common control room envelope (CRE) at Arkansas Nuclear One, Units 1 and 2 (ANO-1 and -2) as follows:
1.
For ANO-1, Entergy determined that the maximum tested value for inleakage into the CRE was 40 standard cubic feet per minute (scfm), which is more than the value of 10 cfm assumed in the design-basis radiological dose analyses for Control Room Habitability (CRH). This finding required continuation of the use of KI (potassium iodide) as a compensatory action.
2.
For ANO-2, Entergy determined that the maximum tested value for inleakage into the CRE was 40 scfm, which is less than the value of 61 cfm assumed in the design-basis radiological dose analyses for CRH.
On June 24, 2004, Entergy submitted a License Amendment Request (LAR) to revise the ANO-1 Safety Analysis Report (SAR) in order to retire the compensatory measure of using KI.
The LAR was required because Entergys proposed revision to the SAR involved an increase in the Maximum Hypothetical Accident dose to the control room, which constituted more than a minimal increase in dose consequences per Section 50.59 of Title 10 of the Code of Federal Regulations. Entergy subsequently withdrew the LAR on May 2, 2006, and indicated that it would pursue alternate means for providing margin to the tested inleakage values for compliance with GDC 19 without relying on KI. In a subsequent letter dated February 14, 2007, Entergy committed to submitting a proposed LAR for ANO-1 using an alternate source term (AST) methodology to eliminate the existing CRE compensatory measure by October 31, 2007.
Entergy indicated the only toxic gas considered in the ANO licensing basis is chlorine and that no credit is taken for control room design in limiting the effects of toxic gas releases.
Therefore, unfiltered inleakage of toxic gas is not considered in the analysis. Entergy indicated that it is currently developing a basis for removing the chlorine detectors using risk-informed methodologies and methods described in Regulatory Guide 1.78, Revision 1. Entergy also indicated that reactor control capability is maintained from either the control room or the alternate shutdown panel in the event of smoke.
The GL 2003-01 further requested that licensees assess their technical specifications (TS) to determine if they verify the integrity of the CRE, including ongoing verification of the inleakage assumed in the design-basis analysis for CRH, and in light of the demonstrated inadequacy of a delta () P measurement to alone provide such verification (GL 2003-01, Item 1c). Entergy stated that neither unit has a TS requirement for P testing and, therefore, the surveillance requirements were inadequate. In its August 28, 2003, response, Entergy indicated that it would submit an LAR to adopt TS surveillance requirements that verify CRH meeting the intent of Technical Specifications Task Force (TSTF) Traveler TSTF-448, Control Room Habitability, and final NRC position. In a subsequent response dated February 14, 2007, Entergy committed to submit proposed LARs for ANO-1 and ANO-2 in accordance with TSTF-448, Revision 3, by October 31, 2007.
T. Mitchell Entergys responses as described above, its commitment to submit an LAR to adopt an AST methodology for ANO-1, and its commitment to submit an LAR based on TSTF-448 for ANO-1 and ANO-2, are acceptable for the purposes of closing out the Entergys response to GL 2003-01.
If you have any questions regarding this correspondence, please contact me at 301-415-1447.
Sincerely,
/RA/
Farideh E. Saba, Project Manager Plant Licensing Branch IV Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-313 and 50-368 cc: See next page
ML070530685 OFFICE NRR/LPL4/PM NRR/LPL4/LA NRR/SCVB/BC NRR/PGCB/BC NRR/LPL4/BC NAME FSaba LFeizollahi RDenning CJackson DTerao DATE 3/1/07 3/1/07 3/5/07 3/1/07 3/5/07
February 2007 Arkansas Nuclear One cc:
Executive Vice President
& Chief Operating Officer Entergy Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995 General Manager Plant Operations Entergy Operations, Inc.
Arkansas Nuclear One 1448 SR 333 Russellville, AR 72802 Director, Nuclear Safety Assurance Entergy Operations, Inc.
Arkansas Nuclear One 1448 SR 333 Russellville, AR 72802 Manager, Licensing Entergy Operations, Inc.
Arkansas Nuclear One 1448 SR 333 Russellville, AR 72802 Director, Nuclear Safety & Licensing Entergy Operations, Inc.
1340 Echelon Parkway Jackson, MS 39213-8298 Section Chief, Division of Health Radiation Control Section Arkansas Department of Health and Human Services 4815 West Markham Street, Slot 30 Little Rock, AR 72205-3867 Section Chief, Division of Health Emergency Management Section Arkansas Department of Health and Human Services 4815 West Markham Street, Slot 30 Little Rock, AR 72205-3867 Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 310 London, AR 72847 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 County Judge of Pope County 100 W. Main Street Russellville, AR 72801 Vice President, Operations Support Entergy Operations, Inc.
P.O. Box 31995 Jackson, MS 39286-1995