ML040780668
| ML040780668 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 03/12/2004 |
| From: | Balduzzi M Entergy Nuclear Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 2.04.019 | |
| Download: ML040780668 (5) | |
Text
En tergy Entergy Nuclear Operations, Inc.
Pilgrim Nuclear Power Station 600 Rocky Hill Road Plymouth, MA 02360 Michael A. Balduzzi Site Vice President March 12, 2004 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555-0001
SUBJECT:
Entergy Nuclear Operations, Inc.
Pilgrim Nuclear Power Station Docket No. 50-293 License No. DPR-35 Response to NRC Request for Additional Information on License Amendment Request to Amend Technical Specifications (TS)
Table 3.2.C-1
REFERENCE:
Entergy Letter No. 2.03.090, License Amendment Request to Amend Technical Specifications (TS) Table 3.2.C-1, dated August 19, 2003.
LETTER NUMBER:
2.04.019
Dear Sir or Madam:
The attachment to this letter provides Pilgrim response to an NRC Request for Additional Information (RAI) related to the proposed License Amendment to amend TS Table 3.2.C-1.
The RAI was e-mailed to us on January 30, 2004.
This response does not impact the no significant hazards consideration determination (10 CFR 50.92(c)) provided in the referenced submittal.
There are no commitments contained in this letter.Entergy Nuclear Operations, Inc.
If you have any questions or require additional information, please contact Mr. Bryan Ford, Licensing Manager, at (508) 830-8403.
I declare under penalty of perjury that the foregoing is true and correct. Executed on the 12th day of March 2004.
Sincerely, Michael A. Balduzzi WGL/dm
Attachment:
Pilgrim Response to NRC Request for Additional Information (3 pages) 204019 A
Entergy Nuclear Operations, Inc.
Letter Number: 2.04.019 Pilgrim Nuclear Power Station Page 2 cc:
Mr. Travis Tate, Project Manager Office of Nuclear Reactor Regulation Mail Stop: 0-8B-1 U.S. Nuclear Regulatory Commission 1 White Flint North 11555 Rockville Pike Rockville, MD 20852 U.S. Nuclear Regulatory Commission Region 1 475 Allendale Road King of Prussia, PA 19406 Senior Resident Inspector Pilgrim Nuclear Power Station 204019
ATTACHMENT Pilgrim Nuclear Power Station Pilgrim Response to NRC Request for Additional Information
References:
Entergy Letter No. 2.03.090, License Amendment Request to Amend Technical Specification (TS) Table 3.2.C-.1, dated August 19, 2003.
NRC QUESTION:
- 1.
In your application dated August 19, 2003, you reference BECO Letter No.91-005, dated January 22,1991, which proposed changes to the Pilgrim Technical Specifications to implement the ARTS (Average Power Range Monitor, Rod Block Monitor and Technical Specification) improvement program, as the source of the error in the value of the Rod Block Monitor (RBM) Low Power Set Point (LPSP). Your application requests to correct the RBM LPSP by changing the value from *29% to *25.9%. A review of your January 22,1991, submittal and the supporting General Electric (GE) Topical Report, NEDC-31312-P, indicates that the RBM LPSP value of *29% is consistent with the value requested in the 1991 submittal, reflected in the GE report, and granted in License Amendment (LA) 138. Please provide a basis for the requested value for the RBM LPSP of *25.9%, that includes:
- 1)
The origin of the value and the impact of the proposed change on the initial Pilgrim ARTS program approved by LA 138.
- 2)
A discussion of how the RBM LPSP value was determined
- 3)
A discussion of all analyses affected by the RBM LPSP and the associated impact.
RESPONSE
- 29% did not include adequate margin for instrument uncertainty based on Regulatory Guide 1.105, instrument Setpoints for Safety-Related Systems" and; therefore, would not ensure the 30% Analytical Limit identified in NEDC-31312-P.
The origin of the RBM LPSP Allowable Value
- 25.9% is based on GE Report EDE-49-1290, Rev. 2 and subsequent Pilgrim analysis, as shown below:
=AL- (A12+C12+VPMA 2+-APEA2+VD2) '2-DPEA-BPMA
=30.0-(1.182+0.252+1.112+0.312+1.22)1/2-0.82-1.0
=30.0-2.05-1.82
=26.1 %,
use 25.9% for set point 204019
The definitions of the terms used in the derivation of the LPSP Allowable Value are as follows:
AV = Allowable Value AL = Analytical Limit, 30.0 from GE-NEDC-31312-P Al = Channel Instrument Accuracy Cl = Channel Calibration Accuracy VPMA = Variable Process Measurement Accuracy APEA = Accuracy Primary Element Accuracy VD = Vendor Stated Drift DPEA = Drift Primary Element Accuracy BPMA = Bias Process Measurement Accuracy There is no impact on the initial Pilgrim ARTS program approved by LA138. As explained in the Entergy letter No. 2.03.090, dated August 19, 2003, Pilgrim's procedures and Core Operating Limits Report are enforcing the correct setpoint Allowable Value of
- 25.9%.
- 25.9% was established based on GE Report EDE-49-1290, Rev. 2 and subsequent Pilgrim analysis.
- 3) The RBM LPSP Allowable Value is an operating limit used to ensure the LPSP Analytical Limit of (30%) for the Rod Withdrawal Error (RWE) event as described in NEDC-31312-P is not exceeded. This is further explained in the response for question 2 below.
NRC QUESTION:
- 2.
Please explain how the proposed RBM LPSP value of *25.9% has been considered in the Rod Withdrawal Error (RWE) analysis. Consider the impact, if any, on the inputs/outputs for the analysis.
RESPONSE
The RBM setpoint development and RWE analysis process is described in NEDC-31312-P.
Three RBM setpoints are selected from the RWE analysis to cover three different power ranges (high, intermediate, and low). The combined span of the three ranges is from 30% to 100%
power. Also, the RBM setpoints are selected to limit the change in MCPR during a RWE event so that the core wide transient power dependent MCPR requirements are bounding. Therefore, the RWE event is expected to remain non-limiting from cycle to cycle. Each of these aspects of the RWM are illustrated on Figure 4-9 of NEDC-31312-P which shows an example of the power dependent MCPR limit for core wide transients bounding the power dependent RWE MCPR limit, which is arranged into three separate ranges in stair-step pattern.
The high power range covers operation above the analytical limit power level of 85%. The intermediate power range spans between 65% and 85% and the low power range spans from 30% to 65%. The low power setpoint (LPSP) analytical limit is 30% power (Reference GE Topical Report NEDC-31312-P, Table 4-5a). Therefore, the LPSP of 25.9% is not an input to 204019
the analysis of the RWE event, but is derived from the analytical low power setpoint (LPSP) of 30% considering instrument loop uncertainties. The Allowable Value of 25.9% provides a statistical confidence that power is not greater than 30%.
As described in NEDC-31312-P, the RBM setpoint in each range is a function of the Operating Limit MCPR used to select the setpoint. For example, Figure 4-9 depicts the RBM setpoint in each range for an OLMCPR of 1.20. If the OLMCPR is higher, each RBM setpoint can be raised in accordance with the RWE analysis. The bounding relationship between the analytical RBM setpoint and OLMCPR is depicted on Figure 4-8, of NEDC-31312-P. PNPS has established an RBM setpoint for each power range based on a conservative low full power OLMCPR of 1.30.
The minimum full power OLMCPR for Cycle 15 is 1.37 as reported in the Supplemental Reload Licensing Report. The acceptability of the selected RBM setpoint(s) is verified for each reload core design.
204019