ML073130017
| ML073130017 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 11/15/2007 |
| From: | John Hughey NRC/NRR/ADRO/DORL/LPLI-2 |
| To: | Christian D Virginia Electric & Power Co (VEPCO) |
| Hughey J, NRR/DORL, 301-415-3204 | |
| References | |
| TAC MD3588 | |
| Download: ML073130017 (5) | |
Text
November 15, 2007 Mr. David A. Christian President and Chief Nuclear Officer Virginia Electric and Power Company Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711
SUBJECT:
MILLSTONE POWER STATION, UNIT NO. 2 - REQUEST FOR ADDITIONAL INFORMATION REGARDING TECHNICAL SPECIFICATIONS CHANGES RELATED TO REACTOR PROTECTIVE AND ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION (TAC NO. MD3588)
Dear Mr. Christian:
By letter dated November 8, 2006 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML063130426), supplemented by letters dated May 4 (ADAMS Accession No. ML071240406), and October 4, 2007 (ADAMS Accession No. ML072780150),
Dominion Nuclear Connecticut (the licensee) proposed a License Amendment Request for Millstone Power Station, Unit No. 2, to modify the Technical Specifications (TS) Action and Surveillance Requirements for instrumentation identified in TS Table 2.2-1, TS 3.3.1 and TS 3.3.2. In order to complete its review of the amendment request, the Nuclear Regulatory Commission staff requires a response to the enclosed request for additional information (RAI).
The RAI was sent by e-mail on October 29, 2007, and was discussed via teleconference on October 30, November 1, 2, and 7, 2007, with your staff to ensure that the questions were understandable, the regulatory basis was clear and to determine if the information was previously docketed. Mr. William D. Bartron of your staff agreed to respond to the RAI by December 3, 2007.
Please note that if you do not respond to this letter within the prescribed response time or provide an acceptable alternate date in writing, we may reject your application for amendment under the provisions of Title 10 of the Code of Federal Regulations, Section 2.108. If you have any questions, I can be reached at (301) 415-3204.
Sincerely,
/ra/
John D. Hughey, Project Manager Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-336
Enclosure:
As stated cc w/encl: See next page
Dominion Nuclear Connecticut (the licensee) proposed a License Amendment Request for Millstone Power Station, Unit No. 2, to modify the Technical Specifications (TS) Action and Surveillance Requirements for instrumentation identified in TS Table 2.2-1, TS 3.3.1 and TS 3.3.2. In order to complete its review of the amendment request, the Nuclear Regulatory Commission staff requires a response to the enclosed request for additional information (RAI).
The RAI was sent by e-mail on October 29, 2007, and was discussed via teleconference on October 30, November 1, 2, and 7, 2007, with your staff to ensure that the questions were understandable, the regulatory basis was clear and to determine if the information was previously docketed. Mr. William D. Bartron of your staff agreed to respond to the RAI by December 3, 2007.
Please note that if you do not respond to this letter within the prescribed response time or provide an acceptable alternate date in writing, we may reject your application for amendment under the provisions of Title 10 of the Code of Federal Regulations, Section 2.108. If you have any questions, I can be reached at (301) 415-3204.
Sincerely,
/ra/
John D. Hughey, Project Manager Plant Licensing Branch I-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-336
Enclosure:
As stated cc w/encl: See next page DISTRIBUTION:
PUBLIC RidsNrrLAABaxter RPowell, RGN-I RidsNrrDorlDpr LPLI-2 Reading RidsOgcRp RidsNrrDesEicb RidsNrrDorlLpl1-2 RidsNrrPMJHughey RidsRgn1MailCenter ACCESSION NUMBER: ML073130017
- Concurrence provided by memo OFFICE LPL1-2/PM LPL1-2/PM LPL1-2/LA EICB/BC LPL1-2BC NAME JHughey CSanders ABaxter WKemper HChernoff DATE 11/14/07 11/14/07 11/14/07 10/29/07
- 11/15/07
Enclosure REQUEST FOR ADDITIONAL INFORMATION MILLSTONE POWER STATION, UNIT NO. 2 REACTOR PROTECTIVE SYSTEM AND ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION TAC NO. MD3588 DOCKET NO. 50-336 By letter dated November 8, 2006 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML063130426), supplemented by letter dated May 4, 2007 (ADAMS Accession No. ML071240406), Dominion Nuclear Connecticut (the licensee) proposed a License Amendment Request for Millstone Power Station, Unit No. 2, to modify the Technical Specifications (TS) Action and Surveillance Requirements for instrumentation identified in TS Table 2.2-1, TS 3.3.1 and TS 3.3.2.
By letter dated October 4, 2007 (ADAMS Accession No. ML072780150), the licensee provided Calculation ZPM_Drift-0426012, Zero Power Mode Drift Analysis in Support of LBDCR 06-MP2-036, Rev 0, dated September 14, 2007. The Nuclear Regulatory Commission staff has reviewed the calculation and determined that additional information is needed to complete its review.
Most of the calculations in ZPM_Drift-0426012 are performed using values in decades instead of real numbers. Specifically, the Total Expected Uncertainty, SV error, has been calculated in Section 6.8, Setpoint Derivation, by taking the square root of the sum of the squares of applicable individual uncertainties in decades. Later, in Section 6.8, it is explained that a decade number is the logarithm (log) of a real number, e.g. Log (102) is equal to 2 decades and Log (10-8) is equal to -8 decades. It is explained in Section 6.8 that the related instruments have a percentage span of 10 decades corresponding to the range from 10-8 to 102.
When two numbers in decades are added (+), the result in decades is equal to the log of the product (x) of the two real numbers:
For example: 2 decades + 3 decades is = 5 decades, which is equivalent to log (105) or equivalent to 105 in real numbers or 10,000.
Doing similar addition in real numbers results in 100 (2 decades) +
1000 (3 decades) = 1100.
When two numbers in decades are subtracted (-), the result in decades is equal to the log of the division between the two real numbers:
For example: 3 decades - 2 decades is = 1 decade, which is equivalent to log (101) or equivalent to 10 in real numbers or equal to 1000÷100.
Doing corresponding subtraction in real numbers is 1000 (3 decades) - 100 (2 decades) = 900.
Similarly, squaring a number in decades gives a much different number from squaring the equivalent real numbers:
For example: (3 decades)2 = 9 decades or 109, while (1000)2 = 106.
Most of the formulae used in ZPM_Drift-0426012, specifically for calculating SVerror, are valid for real numbers. International Society for Measurement and Control standard ISA-RP67.04.02-2000 has addressed a similar consideration in Clause 2.3 of Example Calculation - Radiation Trip.
Provide justifications for performing all calculations in ZPM_Drift-0426012, specifically calculation of drift, SVerror, As-found, As-left, and trip setpoint band using numbers in decades instead of real numbers.
Millstone Power Station, Unit No. 2 cc:
Lillian M. Cuoco, Esquire Senior Counsel Dominion Resources Services, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Edward L. Wilds, Jr., Ph.D.
Director, Division of Radiation Department of Environmental Protection 79 Elm Street Hartford, CT 06106-5127 Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406 First Selectmen Town of Waterford 15 Rope Ferry Road Waterford, CT 06385 Charles Brinkman, Director Washington Operations Nuclear Services Westinghouse Electric Company 12300 Twinbrook Pkwy, Suite 330 Rockville, MD 20852 Senior Resident Inspector Millstone Power Station c/o U.S. Nuclear Regulatory Commission P.O. Box 513 Niantic, CT 06357 Mr. J. Alan Price Site Vice President Dominion Nuclear Connecticut, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Mr. J. W. "Bill" Sheehan Co-Chair NEAC 19 Laurel Crest Drive Waterford, CT 06385 Mr. Evan W. Woollacott Co-Chair Nuclear Energy Advisory Council 128 Terry's Plain Road Simsbury, CT 06070 Ms. Nancy Burton 147 Cross Highway Redding Ridge, CT 00870 Mr. Chris L. Funderburk Director, Nuclear Licensing and Operations Support Dominion Resources Services, Inc.
Innsbrook Technical Center 5000 Dominion Boulevard Glen Allen, VA 23060-6711 Mr. William D. Bartron Licensing Supervisor Dominion Nuclear Connecticut, Inc.
Building 475, 5th Floor Rope Ferry Road Waterford, CT 06385 Mr. Joseph Roy, Director of Operations Massachusetts Municipal Wholesale Electric Company Moody Street P.O. Box 426 Ludlow, MA 01056