ML13233A320

License Amendment Request for Submittal of Atmospheric Relative Concentration Values for Use in Control Room Envelope Radiological Dose Analysis Dated September 25, 2012

ML13233A320
Person / Time
Site:	McGuire, Mcguire
Issue date:	08/08/2013
From:	Capps S Duke Energy Carolinas
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
TAC ME9716, TAC ME9717
Download: ML13233A320 (5)

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Steven D. Capps DUKER ENERGY. Vice President McGuire Nuclear Station Duke Energy MG01VP I 12700 Hagers Ferry Road Huntersville, NC 28078 o: 980.875.4805 f: 980.875.4809 Steven.Capps@d uke-energy.com August 8, 2013 10 CFR 50.90 U.S. Nuclear Regulatory Commission Washington, DC 20555-001 ATTENTION: Document Control Desk

Subject:

Duke Energy Carolinas, LLC McGuire Nuclear Station, Units 1 and 2 Docket Nos. 50-369 and 50-370 License Amendment Request for Submittal of Atmospheric Relative Concentration Values for use in Control Room Envelope Radiological Dose Analysis dated September 25, 2012 (TAC Nos. ME9716 and ME9717)

Response to Request for Additional Information Related to the License Amendment Request (LAR)

This letter provides the response to the second request for additional information (RAI) regarding the referenced LAR dated September 25, 2012 (ADAMS No. ML1 227A343). The request was conveyed by the NRC staff from Jason Paige by Electronic Mail dated August 1, 2013. The NRC staffs question and Duke Energy's response is provided in Attachment 1.

The conclusions reached in the original determination that the LAR contains No Significant Hazards Considerations and the basis for the categorical exclusion from performing an Environmental/Impact Statement have not changed as a result of this request for additional information. This letter contains no regulatory commitments.

Please direct any questions you may have in this matter to Lee A. Hentz at (980) 875-4187.

I declare under penalty of perjury that the foregoing is true and correct. Executed on August 8, 2013.

Sincerely, Steven D. Capps Attachment Aoo(

www.duke-energy.com

US Nuclear Regulatory Commission August 8, 2013 Page 2 cc w/

Attachment:

V. M. McCree Regional Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 J. Zeiler NRC Senior Resident Inspector McGuire Nuclear Station J. C Paige (addressee only)

Project Manager (McGuire)

U.S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop 0-8 G9A Rockville, MD 20852-2738 W. L. Cox Ill, Section Chief North Carolina Department of Environment and Natural Resources Division of Environmental Health Radiation Protection Section 1645 Mail Service Center Raleigh, NC 27699-1645

ATTACHMENT 1 REQUEST FOR ADDITIONAL INFORMATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION REGARDING LICENSE AMENDMENT REQUEST RELATED TO ATMOSPHERIC RELATIVE CONCENTRATION VALUES FOR USE IN CONTROL ROOM ENVELOPE RADIOLOGICAL DOSE ANALYSIS MCGUIRE NUCLEAR STATION, UNITS 1 AND 2 By application dated September 25, 2012, Duke Energy submitted a License Amendment Request (LAR) for the McGuire Nuclear Station, Units 1 and 2 (McGuire). The proposed LAR provides selected atmospheric relative concentration values for use in control room radiological dose analysis that were withdrawn during McGuire's request for full scope implementation of the Alternate Source Term (AST). McGuire received U. S. Nuclear Regulatory Commission (NRC) approval for full scope implementation of the AST on March 31,2009.

The NRC staff has reviewed the licensee's submittal and determined that additional information is needed in order to complete our review. On August 1, 2013, the NRC staff and Duke Energy discussed the draft RAI to gain a common understanding of the question. The below RAI reflects the question discussed during the August 1, 2013, call.

1. The first two paragraphs of the "Duke Response" on Page 10 of Attachment 1 to the Duke February 12, 2009, response to a request for additional information (ML090540682) concerning a prior licensing action state that the control room air intakes/inlets are 3.6 meters above plant grade and that the source/release heights were supplied to the ARCON96 computer code with respect to their height above plant grade. The third paragraph states that "[t]he receptor/inlets are 1.5 meters above the roof of the Auxiliary Building. The Auxiliary Building roof is represented in ARCON96 as the base elevation of the receptor/intake, because, the intakes protrude above the roof in a 'candy-cane' shape, with the inlets hooked over to face downward." Source and receptor heights are typically based on plant grade, but in this case the source heights were based on plant grade and the receptor heights were evidently based on the Auxiliary Building roof.

With regard to the current, September 25, 2012, McGuire license amendment request (ML12272A343), are the base elevation(s) of the release heights listed in Table 1 of Attachment 1, and Table 1.b-1 of Attachment 1 to the June 12, 2013, response to a request for additional information (ML13165A321), based on plant grade, the height of the Auxiliary Building roof, or on some other elevation(s)? Please confirm that the receptor heights are based on the Auxiliary Building roof.

Duke Response:

The intake receptor height is based on the Auxiliary Building roof. A revised Table 1 from the License Amendment Request (LAR) dated September 25, 2012 (ML12272A343) and a revised Table 1.b-1 from the Request for Additional Information (RAI) response dated June 12, 2012 (ML13165A321) are provided below, indicating the intake receptor height.

1

In modeling X/Q dispersion factors for the releases contained in the September 25, 2012 LAR, the Auxiliary Building roof was used as the base elevation for all release heights, as well as the intake receptor height for Units 1 and 2.

Using the Auxiliary Building as the base elevation resulted in an intake receptor height of 1.5 meters. Since all the release heights being modeled are based at the same height, the "Elevation Difference" parameter input to ARCON96 was 0.0 meters.

Revised Table I Source Type: MSLBY DOGir DOGout Intake Receptor Height 1.5 m 1.5 m 1.5 m Release Height 1.5 m 12.2 m 12.2 m Sigma-Y 0m 1.48 m 1.48 m Sigma-Z 0m 0m 0m Bldg Cross-sectional Area (Use 0.01 m 2 if assuming 0 per 0.01 m 2 0.01 m 2 0.01 m 2 Regulatory Guide 1.194)

Same Unit (Unit 1):

Distance Disocea Between ecweep 7.5 m / 1920 32.5 m /920 11.8 m / 3090 Source and Receptor/

Release Angle Same Unit (Unit 2):

Distance Disourcean Between weepr 7.5 m / 192' 32.5 m 2940 11.8 m /730 Source and Receptor/

Release Angle Cross Unit (Unit 2 Source to Unit 1 Intake):

Distance Between 108 m / 1060 69.2 m / 970 101.7 m /104' Source and Receptor/

Release Angle Cross Unit (Unit 1 Source to Unit 2 Intake):

Distance Between 108 m / 2780 69.2 m / 2870 101.7 m I 280 0 Source and Receptor/

Release Angle 2

A .

Revised Table I.b-1: Inputs for the Calculation of the Control Room x/Q ("Same Unit Outboard x/Q")

Value Input Unit I Release to Unit1 Unit 2 Release to Unit 2 Intake Intake Intake Receptor Height 1.5 m 1.5 m Release Height 5.8 m 5.8 m Sigma-Y 0m 0m Sigma-Z 0m 0m Horizontal Distance from Source to Receptor 9.5 m 9.5 m Receptor to Source Angle 2820 1020 Building Cross Section Area 0.01 m 2 0.01 m 2 Source Radius 0m 0m Release Flow Rate 0 m 3/sec 0 m 3/sec Release Vertical Velocity 0 m/sec 0 m/sec 3