TSTF-06-25, Response to NRC Request for Additional Information Regarding TSTF-487, Revision 0, Relocate DNB Parameters to the COLR, Dated September 5, 2006
| ML063000475 | |
| Person / Time | |
|---|---|
| Site: | Technical Specifications Task Force |
| Issue date: | 10/27/2006 |
| From: | Crowthers M, Infanger P, Sparkman W, Woods B BWR Owners Group, PWR Owners Group, Technical Specifications Task Force |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| TSTF-06-25, TSTF-487, Rev 0 | |
| Download: ML063000475 (4) | |
Text
11921 Rockville Pike, Suite 100, Rockville, MD 20852 Phone: 301-984-4400, Fax: 301-984-7600 Email: tstf@excelservices.com Administered by EXCEL Services Corporation TECHNICAL SPECIFICATIONS TASK FORCE A JOINT OWNERS GROUP ACTIVITY TSTF October 27, 2006 TSTF-06-25 PROJ0753 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
SUBJECT:
Response to NRC Request for Additional Information Regarding TSTF-487, Revision 0, "Relocate DNB Parameters to the COLR," dated September 5, 2006
REFERENCE:
Letter from T. Kobetz (NRC) to the Technical Specifications Task Force, "Request For Additional Information Regarding TSTF-487, "Relocate DNB Parameters to the COLR," dated September 5, 2006.
Dear Sir or Madam:
In the referenced letter, the NRC requested additional information regarding TSTF-487, Revision 0, "Relocate DNB Parameters to the COLR." TSTF-487 was submitted to the NRC by the TSTF on June 20, 2005. This letter responds to the NRC's referenced request. Our responses are attached.
We believe that the NRC's question and our response are not technical issues, but are based on the interpretation of the requirements of 10 CFR 50.36 and 10 CFR 50.59. Therefore, we request that the NRC's Office of General Counsel be included in the review of our response.
Should you have any questions, please do not hesitate to contact us.
Wesley Sparkman (PWROG/W)
Michael Crowthers (BWROG)
Brian Woods (PWROG/CE)
Paul Infanger (PWROG/B&W)
Enclosure cc:
Tim Kobetz, Technical Specifications Branch, NRC Ross Telson, Technical Specifications Branch, NRC
Response to NRC Request for Additional Information Regarding TSTF-487, Revision 0, "Relocate DNB Parameters to the COLR," dated September 5, 2006 1
Request for Additional Information The TSTF-487 traveler would not make NUREG-1432 consistent with Westinghouse Owners Group (WOG) standard Technical Specifications (STS) (NUREG-1431). Although WOG STS also allows the relocation of the departure from nucleate boiling (DNB) parameters, i.e., reactor coolant system (RCS) Pressure, temperature, and flow, to the Core Operating Limits Report (COLR), it requires a minimum RCS flow rate limit to be maintained in the TS as described in topical report WCAP-14483-A. The proposed TSTF for NUREG-1432 does not have this requirement. It should be noted that the minimum RCS flow rate limit retained in the TS is different from the cycle-specific DNB parameter value, and is the minimum limit based on a staff approved analysis other than the DNB analysis. This TS value is not cycle-specific and, therefore, can not be relocated to the COLR in accordance with Generic Letter 88-16.
The WOG STS's total flow inclusion came out of RAI #2 for WCAP-14483-A, reprinted below:
"Some plants operate with lower steam generator tube plugging levels and thus higher RCS flow rates compared to what is assumed in the safety analyses. However, a change in RCS flow from cycle-to-cycle is an indication of a physical change to the plant that should be reviewed by the staff. We therefore recommend that if RCS flow rate is relocated to the COLR, the minimum limit for RCS total flow based on a staff approved analysis (e.g., maximum tube plugging) should be retained in the technical specifications similar to what is done for the positive limit on moderator temperature coefficient."
Please address the same RAI as it applies to the traveler.
Response
We believe that the NRC's question and our response are not technical issues, but are based on the interpretation of the requirements of 10 CFR 50.36 and 10 CFR 50.59. Therefore, we request that the NRC's Office of General Counsel be included in the review of our response.
The TSTF does not agree that it is necessary to include a value for minimum RCS flow in the Technical Specifications. WCAP-14483-A is not applicable to Combustion Engineering NSSS plants and is not the basis of the requested change. Furthermore, as discussed below, we now believe that the Technical Specification changes made to implement WCAP-14483-A were not consistent with 10 CFR 50.36. The basis for the requested change, as referenced in TSTF-487, is Generic Letter 88-16 and the NRC plant-specific approval of the proposed change for the Palisades plant.
The current method of controlling the DNB related parameters to assure conformance to 10 CFR 50.36 is to state the values determined to be within specified acceptance criteria (usually the limits of the safety analyses) using an approved calculation methodology in the Technical Specifications. The alternative contained in Generic Letter 88-16 controls the values of cycle-specific parameters and assures conformance to 10 CFR 50.36, which calls for specifying the lowest functional performance levels acceptable for continued operation, by specifying the calculation methodology and acceptance criteria in the Technical Specifications. This permits
Response to NRC Request for Additional Information Regarding TSTF-487, Revision 0, "Relocate DNB Parameters to the COLR," dated September 5, 2006 2
operation at any specific value determined by the licensee, using the specified methodology, to be within the acceptance criteria.
The suggestion that the minimum RCS flow rate should be specified in both the TS and the COLR is inconsistent with Generic Letter 88-16. The minimum RCS flow rate is based on an NRC approved calculation methodology and acceptance criteria, the same as the other cycle-specific values relocated to the COLR.
The RAI stated that the minimum RCS flow rate limit retained in the TS is different from the cycle-specific DNB parameter value and is a minimum limit based on the staff approved analysis other than DNB analysis. The RAI stated that this value is not cycle-specific and cannot be relocated in accordance with Generic Letter 88-16. We disagree with this statement. The cycle-specific DNB parameter value that is relocated to the COLR must always be the same as or more restrictive than the staff approved analysis value in order to be consistent with 10 CFR 50.36.
There are many cases in which a staff approved analysis value (for example, peak containment pressure for a feedwater line break) is less restrictive than the most restrictive analysis value placed in the Technical Specifications (for example, the peak containment pressure for a main steam line break). In these cases, every staff approved analysis value is not placed in the TS, only the most limiting value. This is consistent with 10 CFR 50.36, which states that the Limiting Condition for Operation is "the lowest functional capability or performance levels of equipment required for safe operation of the facility." It is inconsistent with 10 CFR 50.36 to list two values in the LCO - one that is most limiting (the COLR value) and one that is less limiting (the non-DNB analysis value). The TS must contain the most limiting value, which is the cycle-specific DNB analysis value that can be relocated the COLR. We do not understand how a TS LCO can contain two limits on the same value, one more restrictive than the other, and be in compliance with 10 CFR 50.36.
In the WCAP RAI #2, the staff stated, "However, a change in RCS flow from cycle-to-cycle is an indication of a physical change to the plant that should be reviewed by the staff." This justification is flawed and does not justify placing a second RCS flow limit in the LCO. The Westinghouse plant Technical Specification referenced in the RAI specifies only the minimum RCS flow. The actual RCS flow can change from cycle-to-cycle with no requirement to obtain NRC staff review provided that the actual flow is greater than the minimum flow stated in the LCO. Furthermore, we see no regulatory basis for the statement that a physical change to the plant should be reviewed by the NRC staff. Physical changes to the plant are controlled by the licensee and may be reviewed and accepted under the requirements of 10 CFR 50.59. Under some circumstances, 10 CFR 50.59 requires that proposed changes to the plant be reviewed by the NRC. However, we are not aware of any generic requirement that cycle-to-cycle changes in RCS flow rate be reviewed by the NRC.
The only apparent purpose of specifying in the Technical Specifications both the RCS minimum flow associated with the maximum steam generator tube plugging assumed in the accident analysis and the cycle-specific minimum RCS flow based on the DNB analysis in the COLR is to force the submittal of a license amendment when the steam generator tube plugging limit is increased. Such a purpose is inappropriate and inconsistent with the regulations. Changes to the plant's design and licensing basis may be made by the licensee under the requirements of
Response to NRC Request for Additional Information Regarding TSTF-487, Revision 0, "Relocate DNB Parameters to the COLR," dated September 5, 2006 3
10 CFR 50.59. This regulation contains criteria for determining when a license amendment should be submitted to obtain prior review and approval of a proposed change to the plant's design or licensing basis. We do not agree with including a value in the Technical Specifications for the sole purpose of requiring NRC review of a plant change that otherwise would be evaluated under 10 CFR 50.59 and be submitted, if required, under that regulation.
In summary, we believe that the proposed change to the STS is consistent with the intent of the regulations and is consistent with the NRC approval of the Palisades license amendment request.
The earlier, inappropriate application of the requirements in another submittal should not be used as a basis for continuing the error in a new application.