05000410/LER-2005-001, Regarding Both Standby Gas Treatment Subsystems Inoperable Due to an Original Design Deficiency
| ML051160195 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 04/15/2005 |
| From: | O'Connor T Constellation Generation Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NMP2L 2123 LER 05-001-00 | |
| Download: ML051160195 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 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)(i)(A), Completion of TS Shutdown |
| 4102005001R00 - NRC Website | |
text
Constellation Energy*
Nine Mile Point Nuclear Station P.O. Box 63 Lycoming,NY 13093 April 15,2005 NMP2L 2123 United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555-0001
SUBJECT:
Nine Mile Point Unit 2 Docket No. 50-410 Facility Operating License No. NPF-69 Licensee Event Report 05-001, "Both Standby Gas Treatment Subsystems Inoperable Due to an Original Design Deficiency" Gentlemen:
In accordance with 10 CFR 50.73(a)(2)(i)(B) and 10 CFR 50.73(a)(2)(v)(C), we are submitting Licensee Event Report 05-001, "Both Standby Gas Treatment SubsystemsInoperable Due to an Original Design Deficiency."
/
.C,0-C, TJO/DEV/sac Attachment cc:
Mr. S. J. Collins, NRC Regional Administrator, Region I Mr. G. K. Hunegs, NRC Senior Resident Inspector
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NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 06/30/2007 (6-2004)
, the NRC may not conduct digits/characters for each block) or sponsor, and a person Is not required to respond to, the Information
- 3. PAGE Nine Mile Point Unit 2 05000410 1 OF 5
- 4. TITLE Both Standby Gas Treatment Subsystems Inoperable Due to an Original Design Deficiency
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED S
IFACILITY NAME DOCKET NUMBER MONTH DAY YEAR YEAR S
EQUENTIAL MONTH DAY YEAR 05000 FACILITY NAME NUMBER 03 17 2005 2005 - 001 -
00 04 15 2005 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TOTHE REQUIREMENTS OF 10 CFR§: (Check all that apply)
O 20.2201(b)
E 20.2203(a)(3)(i) a 50.73(a)(2)(i)(C) 0 50.73(a)(2)(vii) 1 0 20.2201(d)
E3 20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
El 50.73(a)(2)(viii)(A) o 20.2203(a)(1)
El 20.2203(a)(4)
El 50.73(a)(2)(ii)(B) al 50.73(a)(2)(viii)(B) 0_ 20.2203(a)(2)(i)
El 50.36(c)(1)(i)(A)
El 50.73(a)(2)(iii)
El 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL E 20.2203(a)(2)(ii) a 50.36(c)(1)(ii)(A)
El 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x) al 20.2203(a)(2)(iii)
Dl 50.36(c)(2)
E0 50.73(a)(2)(v)(A) a3 73.71(a)(4) 100 E
20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
O 73.71(a)(5)
El 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A) 0 50.73(a)(2)(v)(C)
El OTHER [I 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(B)
D 50.73(a)(2)(v)(D)
Specify In Abstract below or In (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 Form 366A) (17)
IV. Corrective Actions
The operating procedures for primary containment inerting, de-inerting, and purging and for the SGT system have been revised to clearly indicate that when an SGT subsystem is operated with the filter train recirculation line pressure control valve in the manual control mode, the subsystem will be declared inoperable and the associated TS LCO will be entered.
An extent of condition review of selected operating procedures and their associated safety related systems has been completed to determine if there are any other instances where existing procedures contain direction which involves an action that inhibits the ability of a safety-related system to automatically align to perform its design safety-related functions (when called upon to do so) from an alignment for non-safety-related or off-normal functions. No other instances of the type identified for the SGT system were discovered.
A design modification to automatically return the pressure control valves to the automatic operating mode on an SGT initiation signal is also being considered.
V. Additional Information
A. Failed Components:
None
B. Previous similar events
LER 98-23 reported a condition involving an original design deficiency that could have impacted the ability of the SGT system to perform its design function without manual operator action. The deficiency involved initiation circuitry for unit coolers that remove heat from the secondary containment following a DBA and did not affect the actual design or operation of SGT system equipment. Thus, the corrective actions would not have prevented the event described in this LER.
C. Identification of components referred to in this Licensee Event Report:
ComDonents IEEE 805 System ID IEEE 803.1 Function Standby Gas Treatment System BH None Pressure Control Valve BH PCV Secondary Containment (Reactor Building)
NG None Primary Containment NH None Control Room NA None