05000220/LER-2004-002, Regarding Changes and Errors in the Methodology Used by General Electric and Global Nuclear Fuel to Demonstrate Compliance with Emergency Core Cooling System Performance Requirements
| ML042100053 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 07/12/2004 |
| From: | O'Connor T Constellation Energy Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NMP1L 1845 LER 04-002-00 | |
| Download: ML042100053 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(B) |
| 2202004002R00 - NRC Website | |
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Constellation Energy' RO. Box 63 Nine Mile Point Nuclear Station Lycoming, New York 13093 July 12, 2004 NMP1L 1845 United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Nine Mile Point Unit 1 Docket No. 50-220; DPR Licensee Event Report 04-002, "Changes and Errors in the Methodology Used by General Electric and Global Nuclear Fuel to Demonstrate Compliance with Emergency Core Cooling System Performance Requirements" Gentlemen:
In accordance with 10 CFR 50.46(a)(3)(ii) and 10 CFR 50.73(a)(2)(ii)(B), we are submitting Licensee Event Report 04-002, "Changes and Errors in the Methodology Used by General Electric and Global Nuclear Fuel to Demonstrate Compliance with Emergency Core Cooling System Performance Requirements."
Very y y urs,/
imot ~r.
' onnor Plant Mneral Manager TJO/CDMim Attachment cc:
Mr. H. J. Miller, NRC Regional Administrator, Region I Mr. G. K. Hunegs, NRC Senior Resident Inspector r
i.
x I.
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31.2004 (12001)-
(21 the NRC may not conduct or sponsor, and a person is not required to respond to, the digitstcharacters for each block) information collection.
FACILITY NAME (1)
DOCKET NUMBER (2)
PAGE (3)
Nine Mile Point, Unit 1 05000220 1
OF 5
TITLE (4)
Changes and Errors in the Methodology Used by General Electric and Global Nuclear Fuel to Demonstrate Compliance with Emergencv Core Cooling System Performance Re uirements EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
MO DAY YEAR YEAR SEQUENTIAL REV MO DA YEA FACILITY NAME DOCKET NUMBER NUMBER N NO 05000
_I_
05 14 2004 2004 -
002 -
00 07 12 2004 FACILITY NAME DOCKET NUMBER 05000 OPERATING THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) (11)
MODE (9)
POWER l20.2201(b)
T 20.2203(a)(3)(fi)
X 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)
LEVEL (10) 100
_ 20.2201(d) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(x) 20.2203(a)(1) 50.36(c)(1)(i)(A) 50.73(a)(2)(iv)(A)
_ 73.71 (a)(4) 20.2203(a)(2)(i) 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) 20.2203(a)(2)(ii) 50.36(c)(2) 50.73(a)(2)(v)(B)
OTHER 20.2203(a)(2)(iii)
X 50.46(a)(3)(ii) 50.73(a)(2)(v)(C) 20.2203(a)(2)(iv)
_50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) 20.2203(a)(2)(v) 50.73(a)(2)(i)(B) 50.73(a)(2)(vii) 20.2203(a) (2)(vi) 50.73(a)(2)(i)(C) 50.73(a)(2)(viii)(A) 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(B)
LICENSEE CONTACT FOR THIS LER (12)
NAME TELEPHONE NUMBER (Include Area Code)
Miguel A. Armenta, Supervisor Fuels 315-349-7340 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)
CAUSE
SYSTEM COMPONENT MANU-REPORTABLE [
CAUS I
SYSTEM I
COMPONENT Il MANU-l REPORTABLE I
I FACTUREr TO EPIX l
FACTURER l
TO EPIX SUPPLEMENTAL REPORT EXPECTED (14)
EXPECTED SUBMISSION DATE (15)
IMONTH DAY YEAR I
YES (If yes, complete EXPECTED SUBMISSION DATE).
I X I NO I
U I
ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) (16):
On May 14, 2004, at approximately 0917 hours0.0106 days <br />0.255 hours <br />0.00152 weeks <br />3.489185e-4 months <br /> with the plant operating at 100% power, General Electric (GE) informed Nine I ile Point Nuclear Station, LLC, (NMPNS) of a change in the calculation of Peak Cladding Temperature (PCT) and maximum ocal cladding oxidation. A new heat source has been postulated during the Loss of Coolant Accident (LOCA) event which involves the recombination of hydrogen and oxygen within the fuel bundles during core heatup. Based on 10 CFR 50, Appendix K, inputs and assumptions, the additional heat generated resulted in an estimated 25 degree F increase in PCT and a 1.73% increase in maximum local oxidation. Consequently, the previous LOCA analysis was potentially non-conservative relative to PCT and maximum local cladding oxidation, and a conservative estimate of the calculated increase in local cladding oxidation exceeded the 17% limit of 10 CFR 50.46(b)(2) by 1.23%. This event was initially reported to the NRC on May 14, 2004 in an 8-hour non-emergency report in accordance with 10 CFR 50.46(a)(3)(ii) and 10 CFR 50.72(b)(3)(ii)(B).
The cause of this event is that the heating effects of the hydrogen-oxygen recombination phenomenon were not properly considered during the original development of the LOCA evaluation methodology.
Corrective actions include a 2% Maximum Average Planar Linear Heat Generation Rate (MAPLHGR) reduction, an 8% Peak Linear Heat Generation Rate (PLHGR) reduction when the containment is allowed to be deinerted above 25% power, and additional analyses to further evaluate the hydrogen-oxygen recombination phenomenon using more appropriate best-estimate/upper bound LOCA evaluation methodology. NMPNS will provide a supplement to this LER following completion of the evaluation if the results substantially alter the conclusions and/or corrective actions.
NRC FORM 366 (1-2001)
(If more space is required, use additional copies of (If more space Is required, use additional copies of (If more space is required, use additional copies of (If more space is required, use additional copies of NRC Formn 366A) (17)
Ill. Analysis of Event (Cont'd.)
inerting of the containment is delayed for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> following a plant startup and when the containment is deinerted up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> prior to a scheduled shutdown. It was subsequently confirmed that the basis for these Technical Specification provisions is the low probability of a LOCA occurring during the 24-hour periods following startup and prior to shutdown when the containment is allowed to be deinerted. Since the additional heating effects of the hydrogen-oxygen recombination phenomenon have no impact on the probability of a LOCA occurring, NMPNS has concluded that use of the Technical Specification provisions allowing plant operation with the containment deinerted had no significant impact on the safety functions and margins of safety as defined in the Technical Specifications. In addition, based on the current licensing basis LOCA assumptions and supplemental information provided by GE, the administrative controls to apply the 8% PLHGR reduction during plant startups and shutdowns are not required since there would be no credible challenge to the 10 CFR 50.46 limits.
IV. Corrective Actions
- 1. A 2% MAPLHGR reduction was implemented to restore compliance with the 10 CFR 50.46 limits.
- 2. Administrative controls were implemented to ensure that an 8% PLHGR reduction is applied during plant startups and shutdowns when the containment is deinerted. This action is no longer required.
- 3. Additional analyses are planned which will incorporate the effects of the hydrogen-oxygen recombination phenomenon into the more appropriate best-estimate/upper bound LOCA evaluation methodology. NMPNS will provide a supplement to this LER if the results of this evaluation substantially alter the conclusions and/or corrective actions.
V. Additional Information
A.
Failed Components:
None B.
Previous similar events
No previous similar events were identified.
C.
Identification of components referred to in this Licensee Event Report:
Components IEEE 805 System ID IEEE 803A Function Reactor Core AC RCT ECCS BM P, MO Reactor Vessel AD RPV Primary Containment NH N/A Jet Pump AD P