05000269/LER-2016-003, Regarding Engineered Safeguards Protection System Automatic Actuation Output Logic Bypassed
| ML17030A040 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 01/24/2017 |
| From: | Teresa Ray Duke Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 02081523, ONS-2017-001 LER 16-003-00 | |
| Download: ML17030A040 (8) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 10 CFR 50.73(a)(2)(x) 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)(vii), Common Cause Inoperability |
| 2692016003R00 - NRC Website | |
text
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~ ENERGY ONS-2017-001 January 24, 2017 ATTN: Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001 Duke Energy Carolinas, LLC (Duke Energy)
Oconee Nuclear Station (ONS), Unit 1 Docket No. 50-269 Renewed License Nos. DPR-38 Action Request No.: 02081523 10 CFR 50.73 Thomas D. Ray Vice President Oconee Nuclear Station Duke Energy ON01VP I 7800 Rochester Hwy Seneca, sc 29672 o: 864.873.5016 f. 864.873. 4208 Tom.Ray@duke-energy.com Subject: Licensee Event Report 269/2016-003, Revision 0 - Engineered Safeguards Protection System Automatic Actuation Output Logic Bypassed The enclosed Licensee Event Report (LER) describes the discovery of inoperable Engineered Safeguards Protective System (ESPS) Automatic Actuation Output Logic Channels. It was determined that the inoperable condition had existed longer than the time allowed by the Technical Specification (TS) applicable to the ESPS Automatic Actuation Output Logic Channels with no TS actions taken. Additionally, Unit 1 made MODE changes that were not allowed by TS. These conditions, which occurred during start-up from a refueling outage, constitute an "operation or condition prohibited by Technical Specifications" as described by 10 CFR 50.73(a)(2)(i)(B), thus requiring an LERto be submitted.
There are no regulatory commitments associated with this LER.
If you have any questions regarding this submittal, please contact Bob Meixell, Oconee Regulatory Affairs, at 864-873-3279.
Sincerely, 6-°*§ Vice President, Oconee Nuclear Station
Enclosure:
LER 269/2016-0,03: Engineered Safeguards Protection System Automatic Actuation Output Logic Bypassed
ONS-2017-001 January 24, 2017 Page 2 cc:
Ms. Catherine. Haney Administrator Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, Georgia 30303-1257 Mr. James R. Hall, Project Manager (ONS)
(by electronic mail only)
U.S. Nuclear Regulatory Commission 11555 Rockville Pike Mail Stop 0-881 Rockville, MD 20852 Mr. Eddy Crowe NRC Senior Resident Inspector Oconee Nuclear Station INPO (Word File via E-mail)
- ONS-2017-001 January 24, 2017 Page 3 bxc:
ONS Site:
Site PORC Members Director, Organizational Effectiveness: D.M. Hubbard RA MGR: C.J. Wasik RA: Commitment lndex/L.F. Todd#
LER Book*
ONSCommunications@Duke-Energy.com ICES/OE Coard: T.J. Alexander NSRB/S. Harry/EC06L*
ONS Document Management and Information Services (Master File)
- Site Sections drive: \\SA\\ONS LERs\\2016 (PDF copy)
ELL/EC27F*
GO and other sites:
Nuclear Reg Affairs: M.C. Nolan*
NGO/SAA: B.C. Carroll NGO/SA: S.B. Thomas LEGAL: D.A. Cummings*
Site Regulatory Affairs Managers:
C. Fletcher - CNS J. Thomas - MNS L. Grzeck - BNP J. Robertson - HNP A. Pila - RNP
- Hardcopy (All others by E-Mail Distribution)
Enclosure:
LER 269/2016-003: Engineered Safeguards Protection System Automatic Actuation Output Logic, Bypassed
NRCFORM366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2018 (06-2016)
, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Oconee Nuclear Station, Unit 1 05000269 1 of 4
- 4. TITLE Engineered Safeguards Protection System Automatic Actuation Output Logic Bypassed
- 5. EVENT DATE
~* LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR 1
SEQUENTIALrEV MONTH DAY YEAR FACILITY NAME DOCKET NUMBER NUMBER NO.
NA 05000 11 25 2016 2016 -
003 - 0 1
24 2017 FACILITY NAME DOCKET NUMBER NA 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)(i)
D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A) 3 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 S0.73(a)(2)(iii)
D 50. 73(a)(2)(ix)(A}
D 20.2203(a)(2)(i)
D 50.36(c)(1)(i)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
- 10. 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)(5)
D 20.2203(a)(2)(iv)
D 50.46(a)(3)(ii)
D 50.73(a)(2)(v}(C)
D 73.77(a)(1) 0 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)(i)
D 20.2203(a)(2)(vi) 18:1 50.73(a}(2)(i)(B)
D 50.73(a)(2)(vii)
D 73.77(a)(2)(ii)
. C
- ',
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D 50.73(a}(2)(i)(C)
D OTHER Specify in Abstract below or in U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 2. DOCKET 05000269 APPROVED BY OMB: NO. 3150-0104 EXPIRES 10/31/2018 (See fonn 366 above for burden estimate)
- 6. LER NUMBER YEAR I SEQUENTIAL I NUMBER 2016 -
003 REV NO.
00 Unit 1 was in a condition with both ESPS automatic actuation output logic subsystems inoperable for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and 27 minutes while in the Mode of Applicability without having taken the Required Action of TS 3.3.7, Condition A. Additionally, Unit 1 made MODE changes that were not allowed by TS 3.0.4, from MODE 5 to MODE 4, and MODE 4 to MODE 3 with inoperable automatic actuation output logic channels.
Due to Unit 1 operating in a configuration prohibited by TS 3.3.7, this event is reportable to the NJRC and an LER is required per 10 CFR 50.73(a)(2)(i)(B) 'Any operation or condition which was prohibited by plant Technical Specifications.' The manual initiation functions required by TS 3.3.6 remained OPERABLE; therefore, the condition did not constitute a loss of safety function.
At the time this condition was identified, Oconee Unit 1 was in MODE 3, and Units 2 and 3 were operating in MODE 1 at approximately 100% power. There were no structures, systems or components out of service at the time of this event that contributed to this event. No change in plant MODE or reactor power occurred on any unit as a result of the conditions described within this report.
EVENT DESCRIPTION
Oconee Unit 1 entered MODE 4 on November 24, 2016, at 2301 during startup from a refueling outage.
On November 25, 2016, at 0645, with Unit 1 in MODE 3, the Operations Control Room crew recognized that the Unit 1 Engineered Safeguards Protective System (ESPS) Voters (Odd and Even) 1 and 2 were bypassed, rendering both automatic actuation output logic subsystems inoperable. Oconee Technical Specification (TS) 3.3. 7 requires the automatic actuation output logic for Containment Isolation Valves, Reactor Building (RB) Cooling and RB Spray to be OPERABLE for the Unit 1 plant conditions at the time (MODE 3). At 0728, all ES Voters were placed in Operate and TS 3.3.7 was exited.
Containment Isolation Valves, RB Cooling and RB Spray automatically actuated features were identified as being impacted for the event described in this LER. TS 3.6.3 'Containment Isolation Valves' requires each containment isolation valve to be OPERABLE in MODES 1, 2, 3, and 4. TS 3.6.5 'Reactor Building Spray and Cooling Systems' requires one train of reactor building spray and two trains of reactor building cooling to be OPERABLE during MODES 3 and 4. Therefore, based on TS 3.6.3 and TS 3.6.5 required MODES of applicability, TS 3.3.7 ES Automatic Actuation Output Logic Channels were required for Containment Isolation Valves, RB Cooling and RB Spray during the time the ES Voters were bypassed.
TS 3.3.7 Condition A "One or more automatic actuation output logic channels inoperable," has a Completion Time of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. Oconee Unit 1 was in a condition with both ESPS automatic actuation output logic subsystems inoperable for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> and 27 minutes while in the Mode of Applicability without having taken the Required Action of TS 3.3.7, Condition A. Additionally, Unit 1 made MODE changes that were not allowed by TS from MODE 5 to MODE 4, and MODE 4 to MODE 3 with inoperable automatic actuation output logic channels.
CAUSAL FACTORS The apparent cause that resulted in the condition prohibited by TS was inadequate procedural guidance in MODE change verification procedures and unit startup procedures for ensuring the ESPS was properly aligned prior to being required by TS. Additionally, causal analysis determined that a recent testing procedure revision resulted in the specific conditions which led to the improper ESPS configuration for this Unit 1 startup, conditions which had not been present during startups from previous outages since the digital ESPS was installed.
CORRECTIVE ACTIONS
Immediate/Completed Actions:
U.S. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 2. DOCKET 05000269 APPROVED BY OMB: NO. 3150-0104 EXPIRES 10/31/2018 (See fonn 366 above for burden estimate)
- 6. LER NUMBER YEAR I SEQUENTIAL I NUMBER 2016 -
003 REV NO.
00 Unit 1 ESPS Voter Manual Bypass key switches were placed in Operate and TS 3.3.7 was exited.
Unit 1, 2 and 3 startup procedures were placed on hold and procedure revision requests generated to ensure ESPS Voter Manual Bypass key switches are in Operate prior to entering MODE 4.
Procedure revision requests were generated to revise Unit 1, 2 and 3 MODE change verification procedures to ensure all systems required to be OPERABLE for the next MODE are configured to support OPERABILITY.
Planned Action:
Revise Unit 1, 2 and 3 procedures for unit startup and MODE change verification to ensure systems required to be OPERABLE for the next MODE are configured to support OPERABILITY.
SAFETY ANALYSIS
The subject ~vent is of very low safety significance based on the following considerations. First, although the Engineered Safeguards Protective System (ESPS) automatic actuation signals were bypassed and unavailable, the associated Emergency Core Cooling System (ECCS) functions were available with manual operator actions. Emergency procedures direct operators to verify ES actuation and to manually start ECCS equipment if required for accident conditions. Operators are trained for this scenario and the action is considered to be very reliable. Second, the period of inoperability of the ES signals was very short, approximately 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />, which on an annual basis represents an unavailability of less than 0.1 %. Therefore, the likelihood of a LOCA or other accident requiring ES actuation during this 8 hour9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> period is extremely small.
When these considerations are taken together, it is concluded that the conditional core damage probability for this ES inoperability event is very low and had no significant impact on public health and safety.
ADDITIONAL INFORMATION
Energy Industry Identification System (EllS) codes are identified in the text as [XX].
In Block 13 on page 1, SYSTEM, COMPONENT and MANUFACTURER codes are not included because this event did not involve a component failure, and this event is reportable to ICES. (ICES replaced EPIX.)
SIMILAR EVENTS
A search for similar events revealed LER 269/2011-01, Rev. 1 (ML12055A336), "Reactor Protection System Overpower Flux/Flow/Imbalance Channels Inoperable." The event described in that LER involved operation prohibited by TS during implementation of Oconee Uri it 1 digital Reactor Protection System/Engineered Safeguards (RPS/ES) due to a latent wiring error during installation of the digital RPS/ES modification. The 2011 event causes and corrective actions do not relate to the event described in this LER Page 4 of 4