05000237/LER-2019-002, Scram Due to Main Turbine Low Oil Pressure Trip
| ML19189A087 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 07/02/2019 |
| From: | Karaba P Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| SVPLTR # 19-0042 LER 2019-002-00 | |
| Download: ML19189A087 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(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) |
| 2372019002R00 - NRC Website | |
text
SVPL TR # 19-0042 July 2, 2019 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Dresden Nuclear Power Station, Unit 2 Renewed Facility Operating License Nos. DPR-19 NRG Docket No. 50-237 Dresden Nuclear Power Station 6500 North Dresden Road Morris, IL 60450 10 CFR 50.73
Subject:
Licensee Event Report 237/2019-002-00, Unit 2 Scram due to Main Turbine Low Oil Pressure Trip Enclosed is Licensee Event Report 237/2019-002-00, "Unit 2 Scram due to Main Turbine Low Oil Pressure Trip." This report describes an event which is being reported in accordance with 10 CFR 50.73(a)(2)(iv)(A), "Any event or condition that resulted in manual or automatic actuation of any of the systems listed in paragraph (a)(2)(iv)(B) of this section."
There are no regulatory commitments contained in this submittal.
Should you have any questions concerning this letter, please contact Mr. Bruce Franzen at (815) 416-2800.
Peter J Karaba Site Vice President Dresden Nuclear Power Station Enclosure Licensee Event Report 237/2019-002-00 cc:
Regional Administrator - NRG Region Ill NRG Senior Resident Inspector-Dresden Nuclear Power Station
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 03/31/2020 (04-2018)
, the NRG may not conduct or sponsor, and a person
- ,ft is not required to respond to, the info.nation collection.
3.Page Dresden Nuclear Power Station, Unit 2 05000237 1
OF 3
- 4. Title Unit 2 Scram due to Main Turbine Low Oil Pressure Trip
- 5. Event Date
- 6. LEA Number
- 7. Report Date
- 8. Other Facilities Involved I
Sequential I Rev Facility Name Docket Number Month Day Vear Vear Number No.
Month Day Vear N/A 05000 Facility Name Docket Number 05 09 2019 2019 -
002 00 07 02 2019 N/A
- 05000,
- 9. Operating Mode
- 11. This Report is Submitted Pursuant to the Requirements of 10 CFR §: (Check all that apply)
D 20.2201(b)
D 20.2203(a)(3)(il D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A) 1 D 20.2201(d)
D 20.2203(a)(3)(ii)
D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4)
D 50.73(a)(2)(iii)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(i)
D 50.36(c)(1 )(i)(A)
[gJ 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x) 1 O. Power Level D 20.2203(a)(2)(ii)
D 50.36(c)(1 )(ii)(A)
D 50.73(a)(2)(v)(A)
D 73.71(a)(4)
D 20.2203(a)(2)(iii)
D 50.36(c)(2)
D 50.73(a)(2)(v)(B)
D 73.71(a)(s)
D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50.73(a)(2)(v)(C)
D 73.77(a)(1J 100 D 20.2203(a)(2)(v)
D 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 73.77(a)(2)(il D 20.2203(a)(2)(vi)
D 50.73(a)(2)(i)(B)
D 50.73(a)(2)(vii)
D 73.77(a)(2)(ii)
"1
.g,,
D 50.73(a)(2)(i)(C)
D Other (Specify in Abstract below or in C.
Cause of Event
SEQUENTIAL NUMBER 002 REV NO.
00 The root cause of the scram event was inadequate work instructions. The 2013 work order instructions contained an unrecognized critical activity that lacked the detail needed to prevent human error during installation of the quill shaft oil gasket.
D.
Safety Analysis
The safety significance of this event was minimal. All systems responded as designed to the automatic turbine trip by initiating an automatic reactor scram without complications. Operators performed required actions safety and in accordance with procedures and training.
A risk assessment of the turbine trip was performed for this event. The resulting assessment concluded that the event was not risk significant since Conditional Core Damage Probability and Conditional Large Early Release Probability were below the threshold.
E.
Corrective Actions
Corrective actions include updating the model work orders for main turbine front standard maintenance by adding the proper level of detail when installing the quill shaft oil gasket. Also, post-maintenance testing practices for verifying oil flow are incorporated into the work orders. Additionally, actions have been created to address the extent of the identified condition.
F.
Previous Occurrences
A previous event related to a main turbine main shaft oil pump failure occurred on Dresden, Unit 3. The main shaft oil pump failure is described in LER 05000249/2019-002-00 and did not have the same causal factors.
G. Component Failure Data
General Electric [G080] main shaft oil pump [P] failed to provide the required oil pressure for the main turbine oil system [TD]. Page _3_ of _3_