ML093280238
| ML093280238 | |
| Person / Time | |
|---|---|
| Site: | North Anna  |
| Issue date: | 11/23/2009 |
| From: | Price J Virginia Electric & Power Co (VEPCO) |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 09-688 | |
| Download: ML093280238 (14) | |
Text
10 CFR 50.90 VIRGINIA ELECTRIC AND POWER COMPANY RICHMOND, VIRGINIA 23261 November 23,2009 U.S. Nuclear Regulatory Commission Serial No. 09-6813 Attention: Document Control Desk NL&OS/ETS RO Washington, D.C. 20555 Docket Nos. 50-3313/339 License Nos. NPF-4/7 VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)
NORTH ANNA POWER STATION UNITS 1 AND 2 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION FOR PROPOSED LICENSE AMENDMENT REQUEST ADOPTION OF TSTF-490. REVISION O. REGARDING DELETION OF E-BAR DEFINITION AND REVISION TO RCS SPECIFIC ACTIVITY In a letter dated December 17, 2008 (Serial No. 08-0729), Dominion requE~sted amendments, in the form of changes to the Technical Specifications (TS) to Facility Operating License Numbers NPF-4 and NPF-7, for North Anna Power Station Units 1 and 2, respectively. The proposed amendment would replace the current Technical Specifications limits on reactor coolant system (RCS) gross specific activity with a new limit on RCS noble gas specific activity. In an October 21, 2009 e-mail, the NRC staff requested additional information (RAI) to complete the review of the proposed license amendment request. to this letter provides the requested additional information and addre~sses another NRC concern communicated to the Technical Specification Task Force that is applicable to North Anna. To address the NRC's RAI, Dominion is revising the proposed TS change to remove the Notes from surveillance requirements (SR) 3.4.16.1 and SR 3.4.16.2. Accordingly, revised marked-up and typed Technical Specification pages and the affected marked-Up Bases pages are included in Attachment 2. Please USE~ the revised Technical Specification pages to complete your review of our December 17, 2008 amendment request.
The information provided in this letter, including the changes to the Technical Specifications, does not affect the conclusion of the significant hazards consideration discussion provided in Dominion letter dated December 17, 2008 (Serial No. 08-0729).
Serial No.09-688 Docket Nos. 50-338/339 RAl- E-Bar and ReS Specific Activity Page 2 of 3 If you have any questions or require additional information, please contact Mr. Thomas Shaub at (804) 273-2763.
Very truly yours, rice resident - Nuclear Engineering
Attachment:
- 1. Response to Request for Additional Information
- 2. Marked-up and Typed TS Pages and Marked-up Bases Pages Commitments made in this letter: None COMMONWEALTH OF VIRGINIA COUNTY OF HENRICO The foregoing document was acknowledged before me, in and for the County and Commonwealth aforesaid, today by J. Alan Price, who is Vice President - Nuclear Engineering, of Virginia Electric and Power Company. He has affirmed before me that he is duly authorized to execute and file the foregoing document in behalf of that Company, and that the statements in the document are true to the best of his knowledge and belief.
Acknowledged before me this X3nAdayof NOV{Yt\\1(X ,2009.
My Commission Expires: __4...!...\:...::w----=.1_\~___=__ _
l}-l~JJd~
GINGER L. AlUGOOO
~PUbIIC NoIIf1 PuIIIIc COfnmDIwI.... of VIftIIII C
""7 "
Serial No. 0!3-688 Docket Nos. 50-338/339 RAI- E-Bar and ReS Specific Activity Page 3 of 3 cc: U.S. Nuclear Regulatory Commission Region II Sam Nunn Atlanta Federal Center 61 Forsyth Street, SW Suite 23T85 Atlanta, Georgia 30303 Mr. J. E. Reasor, Jr.
Old Dominion Electric Cooperative Innsbrook Corporate Center 4201 Dominion Blvd.
Suite 300 Glen Allen, Virginia 23060 State Health Commissioner Virginia Department of Health James Madison Building - 7th floor 109 Governor Street Suite 730 Richmond, Virginia 23219 NRC Senior Resident Inspector North Anna Power Station Ms. K. R. Cotton NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mai I Stop 08 G9A 11555 Rockville Pike Rockville, Maryland 20852 Dr. V. Sreenivas NRC Project Manager U. S. Nuclear Regulatory Commission One White Flint North Mai I Stop 08 G9A 11555 Rockville Pike Rockville, Maryland 20852
Serial No.09-688 Docket Nos. 50-338/339 RAI - E-Bar and ReS Specific Activity ATTACHMENT 1 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION PROPOSED LICENSE AMENDMENT REQUEST ADOPTION OF TSTF-490, REVISION 0, REGARDING DELETION OF E-BAR DEFINITION AND REVISION TO RCS SPECIFIC ACTIVITY VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)
NORTH ANNA POWER STATION UNITS 1 AND 2
Serial No.09-688 Docket Nos. 50-33B/339 RAI - E-Bar and ReS Specific Activity Page 1 of 4 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION
Background
By letter dated December 17, 2008 (Agencywide Documents and Access Management System Accession No. ML083530982), Virginia Electric and Power Company submitted a license amendment for North Anna Power Station, Units 1 and 2. The proposed amendment will revise Technical Specification (TS) to adopt Technical Specification Task Force (TSTF) - 490, "Deletion of E-Bar Definition and Revision to RCS Specific Activity," for North Anna Power Station, Unit Nos. 1 and 2. The proposed changes would replace the current Technical Specification 3.4.16 limit on RCS gross specific activity with a new limit on RCS noble gas specific activity. The noble gas specific activity limit would be based on a new dose equivalent XE-133 definition that would replace the current E-Bar average disintegration energy definition.
In an October 21, 2009 e-mail, the Nuclear Regulatory Commission staff requested the additional information to complete its review of the proposed TS changes. In sepal'ate discussions with the Technical Specification Task Force (TSTF) , the NRC raised several additional generic concerns regarding TSTF-490. Consequently, Dominion is providing additional information for the concern applicable to North Anna.
NRC Question "In the subject license amendment request, the licensee proposed TS changes to revise Limiting Condition for Operation (LCO) 3.4.16, "RCS Specific Activity," APPLICABILITY requirements to specify that the LCO is applicable in MODES 1, 2, 3, and 4. In accordance with this proposal, the licensee also proposed to add the NOTE that states, "Only required to be performed in MODE 1." to the surveillance requirements of the TS, thus removing the applicability of the surveillance requirements to other MODES.
The NRC staff has a concern about the proposed addition of the aforementioned NOTE.
The proposed change revises the conditions for sampling, and may exclude sampling during the plant conditions where LCO 3.4.16 may be exceeded. After transient conditions (Le. reactor trip, plant depressurization, shutdown or startup) that end in MODES 2, 3, or 4, the SR is not required to be performed. Isotopic spiking and fuel failures are more likely during transient conditions than during steady state plant operations.
Because LCO 3.4.16 could potentially be exceeded after plant transient or power changes, please justify why sampling is no longer needed in the plant MODES that are proposed to be eliminated and justify how the LCO 3.4.16 remains consistent with the design bases analysis from which the LCO limits are derived (Le. main steamline bmak, steam generator tube rupture, etc.). Furthermore, please justify why there is an apparent disparity between the modes of applicability (MODES 1, 2, 3, and 4) and the limited mode (MODE 1) under which the surveillance is required."
Serial No.09-688 Docket Nos. 50-338/339 RAI - E-Bar and ReS Specific Activity Page 2 of 4 Dominion Response Even though Surveillance Requirements (SR) 3.4.16.1 and 3.4.16.2 do not require the SR to be performed in MODES 2, 3, and 4, these surveillance requirements are still required to be met during all Modes of Applicability (MODES 1, 2, 3, and 4) in accordance with SR 3.0.1. If at any time during MODES 1 through 4 if then3 is information or plant indication that SR 3.4.16.1 or SR 3.4.16.2 may not be met, they are required to be performed to ensure there is not a failure to meet the LCO. However, after additional discussion with the industry and the NRC regarding the surveillance requirements and the Notes, Dominion is removing the limitation (i.e., the NOTE) on Surveillance Requirements (SR) 3.4.16.1 and SR 3.4.16.2. Thus, the surveillances will be required to be performed during all Modes of Applicability (MODES 1, 2, 3, and 4),
which will ensure the potential consequences of a steam line break or steam generator tube rupture are bounded by the approved accident analysis. The TS surveillances are revised to eliminate the proposed Note in SR 3.4.16.1 and delete the existing NotB in SR 3.4.16.2 as follows:
SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.16.1 Verify reactor coolant gross specific activity
- ~**~*GGf~*tJ~/9rft; Verify reactor coolant DOSE EQUIVALENT XE-133 7 days specific activity :s 197 b1Ci/gm.
SR 3.4.16.2 NOTE Only required to be performed in MODE 1.
Verify reactor coolant DOSE EQUIVALENT 1-131 14 days specific activity:S 1.0 ~Ci/gm.
Between 2 and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after a THERMAL POWER changl3 of ~ 15% RTP within a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> eriod Corrected marked-up and typed Technical Specification pages and the associated marked-up bases pages are provided in Attachment 2 to this letter.
Serial No.09-688 Docket Nos. 50-338/339 RAI - E-Bar and ReS Specific Activity Page 3 of 4 ADDITIONAL NRC ISSUES/CONCERNS NRC Question/Concern "The staff requires confirmation that the site-specific limits for both DEI and DEX, and the DCFs used for the determination of DEI and DEX surveillances, are consistent with the current design basis dose analyses (SGTR and MSLB). Also for DEX, the staff requires the DCFs and RCS radioisotopic concentrations to verify the proposed DEX limit. Thus, the licensee should provide calculation of the site specific limits on DEI and DEX or provide the input and assumptions for the calculation so that the NRC can confirm."
Dominion Response Although North Anna is licensed to 10 CFR 50.67, the station is maintaining the current conversion factors in the definition of dose equivalent 1-131 (DEI). The current definition of dose equivalent 1-131 allows DEI to be calculated using either TID-14844 or RG 1.109 dose conversion factors (DCFs) and is based upon information presentee! in letters dated September 12, 2003 and May 7, 2004 (Serial No.03-464 and 03-464D) and approved in amendments 240/241, dated June 15, 2005 (TAC Nos. MC0776 and MC0777).
The information presented and approved in the letters above, discusses the acceptability for the pre-accident and concurrent iodine spike source terms to be based on RG 1.109 DCFs and the doses to be calculated using Federal Guidance Report No.
11 (FGR-11). RG 1.183 requires that the pre-accident and concurrent iodine spikes used in design basis analyses be based on the maximum value permitted by Technical Specifications. The North Anna main steamline break (MSLB) and steam generator tube rupture (SGTR) accidents are analyzed using the maximum reactor coolant system activity. Dose conversion factors from FGR-11 are used to calculate the Total Effective Dose Equivalent consequences described using the guidance from RG 1.183 while the 1 IJCilgm DEI inventory is calculated using RG 1.109 dose conversion factors. RG 1.109 DCFs result in a lower total allowable iodine inventory in the RCS than would be attainable using FGR-11 DCFs. Amendments 240/241 approved the use of DCFs from either RG 1.109 or TID-14844 to perform the Technical Specification surveillance for DEI. The station DEI surveillance uses TID-14844 DCFs and the definition of DEI allows the flexibility, approved in amendments 240/241, to upgrade to RG 1.109 DCFs.
The DCFs used to determine dose from noble gases and the calculation of dose equivalent Xe-133 (DEX) are from Federal Guidance Report No. 12 (FGR-12). DEX is that concentration of Xe-133 (microcuries per gram) that alone would produce the same acute dose to the whole body as the combined activities of noble gas nuclides Kr-8Sm, Kr-85, Kr-87, Kr-88, Xe-131m, Xe-133m, Xe-133, Xe-135m, Xe-135, and Xe-138 actually present. If a specific noble gas nuclide is not detected, it will be assumed to be present at the minimum detectable activity. The calculation of DEX is shown below.
Serial No.09-688 Docket Nos. 50-338/339 RAI - E-Bar and RCS Specific Activity Page 4 of 4 DeSlgn BaSls . DE Xe- 133 base d on FGR 12 DCF S -
Col. 2 Col. 1 Col. 3 Primary Coolant Concentration FGR-12 DCF Xe-133 Equivalent 3 (equivalent to 1 IJCi/gm DEI)
(Sv-m /Bq-sec) (IJCilgm)
(IJCi/gm)
Kr-85 1.19E-16 1.570E+00 1.20E-01 Kr-85m 7.48E-15 6.469E-01 3.10E+00 Kr-87 4.12E-14 3.743E-01 9.89E+00 Kr-88 1.02E-13 1.131 E+OO 7.40E+01 Xe-131 m 3.89E-16 O.OOOE+OO* O.OOE+OO Xe-133m 1.37E-15 9.602E-01 8.43E-01 Xe-133 1.56E-15 8.666E+01 8.67E+01 Xe-135m 2.04E-14 5.818E-02 7.61 E-01 Xe-135 1.19E-14 1.880E+OO 1.43E+01 Xe-138 5.77E-14 2.067E-01 7.65E+OO Total Dose Equivalent Xenon (DEX) 1.97E+02
- Xe-131m is not present in the current design basis accident analysis source term. Its exclusion in the calculation of DEX is conservative since the limit will be lower and the actual surveillance will include either the actual concentration detected or the minimum detectable activity.
Column 1 above lists the DCFs from FGR-12. The RCS concentrations for noble gas isotopes used in the AST analyses, equivalent to the more limiting LCO of 1 IJCi/gm DEI, are given in column 2. Values from column 1 and 2 are multiplied, then normalized to the Xe-133 DCF, and the result displayed in Column 3. The values in Column 3 are summed to determine the DEX limit.
Example: Xe-133 Equivalent of Kr-85 = 1.19E-16
- 1.57E+O / 1.56E-15 = 1.20E-01
Serial No.09-688 Docket Nos. 50-338/339 RAI - E-Bar and ReS Specific Activity ATTACHMENT 2 RESPONSE TO REQUEST FOR ADDITIONAL INFORMATION PROPOSED LICENSE AMENDMENT REQUEST ADOPTION OF TSTF-490, REVISION 0, REGARDING DELETION OF E-BAR DEFINITION AND REVISION TO RCS SPECIFIC ACTIVITY MARKED-UP AND TYPED TS PAGES AND MARKED-UP BASES PAGES VIRGINIA ELECTRIC AND POWER COMPANY (DOMINION)
NORTH ANNA POWER STATION
Serial No.09-688 Docket Nos. 50-3380/339 RAI - E-Bar and ReS Specific Activity Marked-up and Typed Technical Specification Pages
RCS Specific Activity 3.4.16 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.16.1 Verify reactor coolant gross specific activity
< 100/E FlCi/gm.
VGrify reactor coolant DOSE EQUIVALENT XE*133 sQecific activity s 197 jdCilgl11. 7 days SR 3.4.16.2 NOTE Only required to be performed in MODE 1.
Verify reactor coolant DOSE EQUIVALENT 1-131 14 days specific activity s 1.0 IJCi/gm.
Between 2 and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after a THERMAL POWER changE~
of ~ 15% RTP within a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> period S*R****3,4J*-6:,3-****************---------------~-**---------NGT*E----------------------~
Not required to be performed until 31 days aftor a minimum of 2 effective full PO'Nor days and 20 days of MODE 1 operation have elapsed since the reactor '.vus last subcritieui for> 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
Determine E from a sample taken in MODE 1 after a 1g4 Eiays minimum of 2 effective fuH PO'l/OF days and 20 days of MODE 1 operation have olapsed since the fOactor was last suberiticai for> 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
I North Anna Units 1 and 2 3.4.16-2 Amendments ~ ~
RCS Specific Activity 3.4.16 SURVEILLANCE REQUIREMENTS SURVEILLANCE FREQUENCY SR 3.4.16.1 Verify reactor coolant DOSE EQUIVALENT XE- 7 days 133 specific activity ~ 197 ~Ci/gm.
SR 3.4.16.2 Verify reactor coolant DOSE EQUIVALENT 14 days I-131 specific activity ~ 1.0 ~Ci/gm.
AND Between 2 and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after a THERMAL POWER change of
~ 15% RTP withi n a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> period North Anna Units 1 and 2 3.4.16-2 Amendments
Serial No.09-688 Docket Nos. 50-338/339 RAI - E-Bar and ReS Specific Activity Marked-up Technical Specification Bases Page
RCS Specific Activity B 3.4.16 BASES SURVEILLANCE activities in the sample taken. This Surveillance provides REQUIREMENTS an indication of any increase in the noble gas specific (continued) activity.
Trending the results of this Surveillance allows proper remedial action to be taken before reaching the LCO limit under normal operating conditions. The 7 day Frequency considers the low probability of a gross fuel failure during this time.
Due to the inherent difficulty in detecting Kr-85 in a reactor coolant sample due to masking from radioisotopes within similar decay energies, such as F-18 and 1-134, it is acceptable to include the minimum detectable activity for Kr-85 in the SR 3.4.16.1 calculation. If a specific noble gas nuclide listed in the definition of DOSE EQUIVALENT XE-133 is not detected, it should be assumed to be present at the minimum detectable activity.
SR 3.4.16.2 This Surveillance is performed to ensure iodine specific activity remains within the LCO limit during normal operation and following fast power changes when iodine spiking is more apt to occur. The 14 day Frequency is adequate to trend changes in the iodine activity level, considering noble gas activity is monitored every 7 days.
The Frequency, between 2 and 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after a power change
> 15% RTP within a 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> period, is established because the lodine levels peak during this time following the iodine spike initiation; samples at other times would provide accurate results.
North Anna Units 1 and 2 B 3.4.16-5 Revision