05000440/LER-2012-001, For Perry Nuclear Power Plant Regarding Manual Reactor Protection System Actuation Due to Automatic Turbine Generator Runback
| ML12128A003 | |
| Person / Time | |
|---|---|
| Site: | Perry  |
| Issue date: | 04/27/2012 |
| From: | Kaminskas V FirstEnergy Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-12-092 LER 12-001-00 | |
| Download: ML12128A003 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(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 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 4402012001R00 - NRC Website | |
text
FENOC FirstEnergy Nuclear Operating Company Perry Nuclear Power Plant 10 Center Road Perry Ohio 44081 Vito A. Kaminskas Vice President 440-280-5382 Fax: 440-280-8029 April 27, 2012 L-12-092 10 CFR 50.73(a)(2)(iv)(A)
ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Perry Nuclear Power Plant, Unit 1 Docket No. 50-440, License No. NPF-58 Licensee Event Report Submittal Enclosed is Licensee Event Report (LER) 2012-001, Manual Reactor Protection System Actuatio;n due to Automatic Turbine Runback. There are no regulatory commitments contained in this submittai.'
If there are any questions or if additional information is required, please contact Mr. Robert Coad, Manager - Regulatory Compliance, at (440) 280-5328.
Sincerely, Vito A. Kaminskas
Enclosure:
LER 2012-001
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NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB NO. 3150-0104 EXPIRES 10/31/2013 (10-2010)
, the NRC may digits/characters for each block) not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Perry Nuclear Power Plant 05000-440 1 OF 4
- 4. TITLE Manual Reactor Protection System Actuation due to Automatic Turbine Generator Runback
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR I SEQUENTIAL REV MONTHIFACILITY NAME DOCKET NUMBER A YEAR NUMBER I NO.
MONTH DAY YEAR 05000 03 01 2012 2012
- - 001
.00 04 2FACILITY NAME DOCKET NUMBER 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
[- 20.2201(b)
El 20.2203(a)(3)(i)
[- 50.73(a)(2)(i)(C)
E] 50.73(a)(2)(vii) 1L 20.2201 (d)
LI 20.2203(a)(3)(ii)
El 50.73(a)(2)(ii)(A)
E] 50.73(a)(2)(viii)(A)
El 20.2203(a)(1)
El 20.2203(a)(4)
EL 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
_ _ 20.2203(a)(2)(i)
[] 50.36(c)(1)(i)(A)
Ej 50.73(a)(2)(iii)
El 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL El 20.2203(aX2)(ii)
E] 50.36(c)(1)(ii)(A)
[D 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
E] 20.2203(a)(2)(iii)
[] 50.36(c)(2)
El 50.73(a)(2)(v)(A)
[] 73.71 (a)(4) 100
[] 20.2203(a)(2)(iv)
[E 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71 (a)(5)
E] 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
[: 50.73(a)(2)(v)(C)
El OTHER Specify in Abstract below LI 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B)
[E 50.73(a)(2)(v)(D) or in pressure gauge. The condition was validated by comparison with the incorrect value referenced in the SOL. Documents were generated to facilitate calibration of the gauge in accordance with the work management process. The gauge calibration was determined to be a green risk activity to be worked online.
On March 1, 2012, at 0100 hours0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br />, technicians commenced calibration of the generator stator water cooling inlet pressure gauge. A low pressure condition was created in a sensing line common to the gauge and associated pressure switch when a technician opened the gauge isolation valve. The low pressure condition resulted in pressure switch actuation on low pressure and caused a turbine generator runback. Turbine bypass valves began to open and a manual RPS actuation was initiated at 0224 hours0.00259 days <br />0.0622 hours <br />3.703704e-4 weeks <br />8.5232e-5 months <br /> in accordance with plant procedures.
The manual RPS actuation was uncomplicated in that all control rods fully inserted, reactor coolant level and pressure were maintained within expected parameters, and no ECCS systems actuated in response. The RPS functioned as designed.
A Probabilistic Risk Assessment (PRA) evaluation was performed for the March 1, 2012, manual RPS actuation. The analysis indicates that the manual RPS actuation event delta core damage frequency (CDF) of 4.3E-08/yr is well below the acceptable threshold of 1.OE-06/yr as discussed in Regulatory Guide 1.174. Since core damage is required to obtain a large release, the Large Early Release Frequency (LERF) must be below CDF and is therefore below the threshold of 1.OE-07/yr in Regulatory Guide 1.174. The risk of this event is therefore considered to be small in accordance with the regulatory guidance.
CORRECTIVE ACTIONS
An interim order review process has been implemented to ensure work being performed online has an acceptable level of risk. This process will remain in place until training on risk assessment is complete.
Troubleshooting was completed to recreate the low pressure condition and validated the direct cause of the turbine generator runback.
The SOl has been revised to reflect the correct generator stator water cooling inlet pressure value.
The required operating condition for future gauge calibrations will be changed to outage.
An inspection of the gauge snubber will be performed to determine if wear or fouling is present and may have contributed to the pressure response during the gauge calibration.
Additional procedure changes will be implemented and training will be provided to applicable plant personnel with regard to the lessons learned from this event, including risk assessment awareness.
PREVIOUS SIMILAR EVENTS
A review of Licensee Event Reports and the corrective action database for the past three years determined that one similar event had occurred.
LER 2010-003, "Loss of Control Rod Drive Header Pressure Results in Manual RPS Actuation,"
documents an event where operators manually initiated an RPS actuation. The RPS actuation was required due to a failed master trip unit causing an invalid division 2 loss of coolant accident initiation signal.
This event was a result of equipment failure, not a maintenance activity. Therefore, the corrective actions associated with this event would not have reasonably been expected to have prevented the event documented in LER 2012-001.
COMMITMENTS
There are no regulatory commitments contained in this report. Actions described in this document represent intended or planned actions, are described for the NRC's information, and are not regulatory
commitments