IR 05000282/2019011
| ML19079A292 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 03/20/2019 |
| From: | Stoedter K K NRC/RGN-III |
| To: | Sharp S Northern States Power Company, Minnesota |
| References | |
| IR 2019011 | |
| Download: ML19079A292 (12) | |
Text
March 20, 2019
Mr. Scott Sharp Site Vice President Prairie Island Nuclear Generating Plant Northern States Power Company, Minnesota 1717 Wakonade Drive East Welch, MN 55089
-9642
SUBJECT: PRAIRIE ISLAND NUCLEAR GENERATING PLANT, UNITS 1 AND 2 DESIGN BASIS ASSURANCE INSPECTION (PROGRAM);
INSPECTION REPORT 05000282/2019011 AND 05000306/2019011
Dear Mr. Sharp:
On February 15, 2019
, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at your Prairie Island Nuclear Generating Plant, Units 1 and 2, and discussed the results of this inspection with you and other members of your staff.
The results of this inspection are documented in the enclosed report. NRC inspectors documented one finding of very low safety significance (Green) in this report. This finding involved a violation of NRC requirements.
If you contest the violation or significance or severity of the violation documented in this inspection report, you should provide a response within 30 days of the date of this inspection report, with the basis for your denial, to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington
, DC 20555-0001; with copies to the Regional Administrator, Region III; the Director, Office of Enforcement; and the NRC Resident Inspector at Prairie Island
. If you disagree with a cross
-cutting aspect assignment in this report, you should provide a response within 30 days of the date of this inspection report, with the basis for your disagreement, to the U.S.
Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, DC 20555
-0001; with copies to the Regional Administrator, Region III; and the NRC Resident Inspector at Prairie Island
. This letter, its enclosure, and your response (if any) will be made available for public inspection and copying at http://www.nrc.gov/reading
-rm/adams.html and at the NRC Public Document Room in accordance with 10 CFR 2.390, "Public Inspections, Exemptions, Requests for Withholding
."
Sincerely,/RA/ Karla K. Stoedter, Chief Engineering Branch 2 Docket No s.: 05000282 and 05000306 License No s.: DPR-42 and DPR
-60
Enclosure:
IR 05000282/2019011 and 05000306/2019011 cc: Distribution via LISTSERV
ML19079A292 SUNSI Review Complete By: Karla Stoedter ADAMS Yes No Publicly Available Non-Publicly Available Non-Sensitive Sensitive Keyword: NRC-002 OFFICE RIII RIII NAME KStoedter:cl BJose SIGNATURE /RA/ /RA/ DATE 03/20/19 03/20/19 Enclosure U.S. NUCLEAR REGULATORY COMMISSION Inspection Report Docket Number(s):
05000282 and 05000306 License Number(s):
-60 Report Number(s):
05000282/2019011 and 05000306/2019011 Enterprise Identifier:
I-2019-011-0008 Licensee: Northern States Power Company, Minnesota Facility: Prairie Island Nuclear Generating Plant, Units 1 and 2 Location: Welch, MN Inspection Dates:
January 28, 2019
, to February 15, 2019 Inspectors:
N. Feliz-Adorno, Senior Reactor Inspector B. Jose, Senior Reactor Inspector L. Rodriguez, Reactor Inspector Approved By:
Karla K. Stoedter, Chief Engineering Branch 2 Division of Reactor Safety
2
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensee's performance by conducting a Design Basis Assurance Inspection (Program)
at Prairie Island Nuclear Generating Plant, Units 1 and 2
, in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRC's program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information. Findings and violations being considered in the NRC's assessment are summarized in the table below.
List of Findings and Violations Failure to Ensure Valve Inspection Procedure Was Appropriate to Maintain Environmental Qualification of Limitorque Actuators Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000282,05000306/2019011
-01 Open/Closed
[H.12] - Avoid Complacency 71111.21N The inspectors identified a Green finding and an associated Non-Cited Violation of Title 10 of the Code of Federal Regulations
, Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," for the licensee's failure to ensure activities affecting quality were prescribed by documented procedures of a type appropriate to the circumstances and included appropriate quantitative or qualitative acceptance criteria for determining that important activities had been satisfactorily accomplished. Specifically, Procedure D70.1, "Motor Operated Valve Testing," Revision 24, did not verify lubricant conditions were acceptable to maintain the environmental qualification of Limitorque actuators.
3
INSPECTION SCOPES
Inspections were conducted using the appropriate portions of the inspection procedures (IPs) in effect at the beginning of the inspection unless otherwise noted. Currently approved IPs with their attached revision histories are located on the public website at http://www.nrc.gov/reading
-rm/doc-collections/insp
-manual/inspection
-procedure/index.html. Samples were declared complete when the IP requirements most appropriate to the inspection activity were met consistent with Inspection Manual Chapter (IMC) 2515, "Light
-Water Reactor Inspection Program - Operations Phase." The inspectors reviewed selected procedures and records, observed activities, and interviewed personnel to assess licensee performance and compliance with Commission rules and regulations, license conditions, site procedures, and standards.
REACTOR SAFETY
- Design Bases Assurance Inspection (Programs)
The inspectors evaluated the Environmental Qualification Program implementation through the sampling of the following components:
02.01 Select Sample Components to Review
- Primary Containment (Inside Containment)
(1 Sample) Unit 1 Reactor Coolant Loop Pressurizer Channel 1
-Red Pressure Transmitter 1PT
-429 02.01 Select Sample Components to Review
- Risk Significant/Low Design (Inside/Outside Containment)
(8 Sample s)
- (1) D1/D2 Diesel Generator Room Train B Air Intake Solenoid Valve SV
-33498
- (2) 12 Residual Heat Removal Pump Motor MTR 16
-6
- (3) 11 Residual Heat Removal Heat Exchanger to 11 Safety Injection Pump Suction Isolation Valve MV
-32206/MV-32206-Actuator (ACT)
- (4) 22 Turbine Driven Auxiliary Feed Water Control Valve CV
-31999 Operating Limit Switch 31999
-LSOP
- (5) 11 Accumulator to Loop A Cold Leg Isolation Valve MV
-32071/MV-32071-ACT
- (6) Unit 1 Pressurizer Power Operated Relief Valve Isolation Valve MV-32195/MV-32195-ACT
- (7) Unit 1 Containment Sump A Pump's Discharge Header B Control Valve Limit Switch 31438-LSCL
- (8) 11 Containment Spray Pump Motor MTR 15-9
INSPECTION RESULTS
Failure to Ensure Valve Inspection Procedure Was Appropriate to Maintain Environmental Qualification of Limitorque Actuators Cornerstone Significance Cross-Cutting Aspect Report Section Mitigating Systems Green NCV 05000282,05000306/2019011
-01 Open/Closed
[H.12] - Avoid Complacency 71111.21N The inspectors identified a Green finding and an associated Non
-Cited Violation of Title 10 of the Code of Federal Regulations
, Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," for the licensee's failure to ensure activities affecting quality were prescribed by documented procedures of a type appropriate to the circumstances and included appropriate quantitative or qualitative acceptance criteria for determining that important activities had been satisfactorily accomplished. Specifically, Procedure D70.1, "Motor Operated Valve Testing,"
Revision 24, did not verify lubricant conditions were acceptable to maintain the environmental qualification of Limitorque actuators.
Description:
Environmental qualification files ENG-EQ-0106, "EEQ File:
Limitorque Actuators and Motors," Revision 1, and ENG-EQ-0169, "EEQ File: Oils and Greases," Revision 1, qualify safety-related Limitorque actuators and specify lubricant requirements to maintain their qualification. The environmental qualification files require the performance of vendor recommended maintenance in order to maintain the qualification of the actuators.
For lubricants, the vendor recommended maintenance is provided in Limitorque Maintenance Manual Form LC8, "Lubrication Data Form."
The form recommends inspections of the lubricant in the main gear case and the geared limit switch of the actuators to verify, in part, appropriate lubricant quality and consistency.
The licensee credits Procedure D70.1, "Motor Operated Valve Testing," Revision 24, and previous revisions, as the implementing procedure to verify the condition of actuator lubricants is consistent with the requirements of the environmental qualification files (e.g., Form LC8).
Appendix B of the procedure has the licensee inspect and document the as
-found limit switch gear box lubricant condition and the actuator lubricant condition.
It also refers to Table 2, "Lubricant Condition," for grading the lubricant condition as "excellent," "good," "fair," or "poor."
Appendix B of the procedure requires determining whether the lubricant condition is "sat" or "unsat," but does not directly specify which lubricant grades are "sat" and which ones are "unsat." Instead, the instructions provided in Table 2 for the "fair" lubricant grading stated, "Lubrication at a minimal acceptability." Through interviews with licensee personnel, and a review of past work orders (WO), the inspectors confirmed that a lubricant grading of "excellent,"
"good," or "fair" would be deemed "sat" and the lubricant condition would be considered acceptable for continued use.
However, for lubricant graded as "fair," the inspectors noted that the lubricant quality and consistency specifications of Form LC8 would not be met. Specifically, the instructions provided in Table 2 for the "fair" lubricant grading stated:
5 Texture - Grease is sticky and does NOT return to a soft and supple condition when pressed and rubbed between the fingers unless extreme effort is used. Oil separation has occurred and some hardened grease globules may be present.
Cavitation around gearing is evident.
Some contamination is appearing (wear particles, dirt, etc.).
Grease may start to smell burnt.
Lubrication at a minimal acceptability.
In contrast, Form LC8 stated:
Quality - When removing a "fill" or "drain" plug to inspect the lube level, remove a small amount and insure that it is clean and free of any contaminant including water. Should dirt, water, or other foreign matter be found, the units should be flushed with a commercial degreaser/cleaner like Exxon VARSOL #1 or #3 , which is non-corrosive and does not affect seal materials such as Buna N or Viton. Repack unit with fresh lubricant.
Consistency
- The main gear box lubricant should be slightly fluid approximating a standard NLGl
-1 grade consistency or less. Thinners such as Amoco WAYTAC #31 oil may be added provided the volume of thinner does not exceed 20 percent of the total lubricant.
The geared limit switch lube should be soft to the touch approximating an NLGl
-2 consistency or less.
The instructions for a "fair" lubricant in Table 2 of Procedure D70.1 differ from the environmental qualification requirements in Form LC8 because they allow a lubricant to have:
- (1) contaminants in the grease;
- (2) oil separation of the grease; and
- (3) hardened grease globules. Therefore, the inspectors determined Procedure D70.1 was not appropriate because it allowed the licensee to return a Limitorque actuator back to service with lubricants graded as "fair," which did not meet applicable environmental qualification requirements.
In addition, through interviews with licensee personnel, the inspectors learned a lubricant graded as "poor" and "unsat" could be allowed to remain in service without evaluating whether the lubricant continued to meet environmental qualification requirements.
Specifically, Procedure D70.1, Appendix A, Step 3.1 states, "Notify Engineering of any unsatisfactory conditions found and record below." However, the inspectors also learned during these interviews:
- (1) engineering could perform an evaluation and conclude the lubricant was acceptable; (2)the evaluation only considered Motor Operated Valve (MOV) Program requirements; and
- (3) the licensee MOV Program requirements established for lubricants were less restrictive than the applicable environmental qualification requirements. Therefore, the inspectors determined Procedure D70.1 was also not appropriate because it allowed the licensee to return a Limitorque actuator back to service with lubricant graded as "poor," which did not meet applicable environmental qualification requirements.
6 A review of past WOs identified two occasions where a Limitorque actuator was placed back in service with a "fair" lubricant condition. Specifically, WO 00313384 dated February 22, 2016, and WO 00529395 dated January 31, 2018, both for valve MV-32075 (Sump B to the 11 Residual Heat Removal Pump Train A) documented a "fair" lubricant condition in the actuator due to burnt grease flecks found in the motor pinion cavity. On both occasions, the valve was returned to service with a lubricant that did not meet the environmental qualification requirements.
Corrective Action(s):
The licensee entered this issue into their Corrective Action Program t o address the procedural deficiencies identified by the inspectors.
The licensee also performed a review of valve inspection results for the last 10 years and identified one valve (MV
-32075, Sump B to the 11 Residual Heat Removal Pump Train A) which was returned to service with lubricant conditions that did not meet environmental qualification requirements.
However, the licensee re
-evaluated the lubricant inspection results and determined the valve was operable because it is located in a radiation only harsh environment and the radiation evaluation of its qualification was judged to have sufficient margin to compensate for the condition described in the WOs. Corrective Action Reference(s):
501000023141
- 501000023171 Performance Assessment
- Performance Deficiency: The inspectors determined the failure to establish a Limitorque valve inspection procedure appropriate to the circumstances that included appropriate acceptance criteria for determining this important activity had been satisfactorily accomplished was contrary to Title 10 of the Code of Federal Regulations , Part 50, Appendix B, Criterion V, "Instructions, Procedures, and Drawings," and was a performance deficiency.
Specifically, Procedure D70.1, "Motor Operated Valve Testing," Revision 24, did not verify lubricant conditions were acceptable to maintain the environmental qualification of Limitorque actuators.
Screening: The inspectors determined the performance deficiency was more than minor because if left uncorrected, it would have the potential to lead to a more significant safety concern. Specifically, the failure to ensure that lubricant conditions identified during inspections were acceptable to maintain environmental qualification of Limitorque actuators important to safety would have the potential to lead to unqualified valves being deemed acceptable for continued service in the plant.
In particular, the environmental qualification of valve MV-32075 was challenged due to the performance deficiency identified.
Significance:
The inspectors assessed the significance of the finding using Appendix A, "Significance Determination of Reactor Inspection Findings for At
- Power Situations". The inspectors determined the finding affected the Mitigating Systems Cornerstone and assesse d the significance of the finding using Significance Determination Process Appendix A, "The Significance Determination Process for Findings At
-Power," Exhibit 2, "Mitigating Systems Screening Questions."
The finding screened as having very
-low safety significance (Green) because it did not result in the loss of operability or functionality of any Limitorque actuators currently installed in the plant.
Specifically, the licensee performed a review of valve inspection results for the last 10 years and identified one valve (MV
-32075, Sump B to the 11 Residual Heat Removal Pump Train A) which was returned to service with lubricant conditions that did not meet environmental qualification requirements.
However, the licensee re
-evaluated the
7 lubricant inspection results and determined the valve was operable because it is located in a radiation only harsh environment and the radiation evaluation of its qualification was judged to have sufficient margin to compensate for the condition described in the WO s. Cross-cutting Aspect: H.12 - Avoid Complacency: Individuals recognize and plan for the possibility of mistakes, latent issues, and inherent risk, even while expecting successful outcomes. Individuals implement appropriate error reduction tools.
Specifically, when reconstituting the Environmental Qualification Program beginning in 2016, the licensee did not plan for the possibility of latent issues regarding lubricant inspections performed under Procedure D70.1.
The licensee assumed the pre
-reconstitution environmental qualification evaluations had verified the procedure was appropriate to maintain the qualification of Limitorque actuators.
Enforcement
- Violation: Title 10 of the Code of Federal Regulations, Part 50, Appendix B, Criterion V, "Instructions Procedures, and Drawings," requires that activities affecting quality shall be prescribed by documented instructions, procedures, or drawings of a type appropriate to the circumstances and shall be accomplished in accordance with these instructions, procedures, or drawings. It also requires that instructions, procedures, or drawings shall include appropriate quantitative or qualitative acceptance criteria for determining that important activities have been satisfactorily accomplished.
The licensee established inspection Procedure D70.1, "Motor Operated Valve Testing," Revision 24, as the implementing procedure for MOV Program inspections of safety
-related Limitorque valves and credited it to verify lubricant conditions were acceptable to maintain the environmental qualification of the valve actuators as established by ENG
-EQ-0106, an activity affecting quality.
Contrary to the above, as of February 15, 2019, activities affecting quality were not prescribed by documented procedures of a type appropriate to the circumstances and did not include appropriate quantitative or qualitative acceptance criteria for determining that important activities had been satisfactorily accomplished.
Specifically, Procedure D70.1 did not contain:
- (1) instructions for performing safety
-related Limitorque actuator lubricant environmental qualification maintenance required by ENG
-EQ-0106, and
- (2) acceptance criteria for determining that this important activity had been satisfactorily accomplished.
Although Procedure D70.1 contained instructions to observe and grade the lubricants of safety
-related Limitorque actuators, these instructions were not appropriate to the circumstance to ensure the lubricant's quality and consistency specified in ENG-EQ-0106 continued to be met.
On two occasions, February 22, 2016
, and January 31, 2018, the licensee used Procedure D70.1 to place valve MV
-32075 into service with lubricant graded as "fair" even though the lubricant contained in the valve actuator failed to meet the consistency and quality requirements of ENG-EQ-0106. Enforcement Action: This violation is being treated as an Non
-Cited Violation, consistent with Section 2.3.2 of the Enforcement Policy.
EXIT MEETINGS AND DEBRIEFS
The inspectors confirmed that proprietary information was controlled to protect from public disclosure.
On February 15, 2019, the inspector presented the Design Basis Assurance Inspection (Program) inspection results to Mr. Scott Sharp and other members of the licensee staff.
DOCUMENTS REVIEWED
71111.21N-Design Bases Assurance Inspection (Programs)
CR 01360690; NRC identified Procedure Enhancements for MOV Testing; 11/26/
12 CR 01455269; MV
-32075 Actuator Grease Rated as "Fair"; 11/08/
14 CGE-PI-0120; Commercial Grade Application Evaluation for Grease, Chevron EP1; 07/22/19 92 D70.1; Motor Operated Valve Testing; Revision 24
D70.11; Motor Valve Actuator Removal and Replacement; Revision 0
D70.3; Votes Force Sensor; Revision 2
D70.7; Motor Operated Valve Maintenance Procedure SMB1
- SMB4; Revision 1
EC 22547; Replace 150 ft
-lb Magnesium Motor Rotors with Aluminum Rotors; 02/12/20 19 ENG-EQ-001; The Derivation of the EEQ Design Basis Accident Profiles; Revision 1
ENG-EQ-0103; EEQ File: Namco EA180 Series Switches with EC290 or EC210 Environmental Seals; Revision 1
ENG-EQ-0106; EEQ File: Limitorque Actuators and Motors; Revision 1
ENG-EQ-0169; EEQ File: Oils and Greases; Revision 1
FP-PE-MOV-07; Motor Operated Valve Program; Revision 2
FP-SC-PE-05; Shelf Life Program; Revision 10
H8.0; EEQ User's Manual; Revision 22
H8.E.1.33.DG; EEQ
- Limitorque Motors and Actuators (SMB/SB); Revision 9
H8-A; EEQ User's Manual Appendix A EEQ Master List; Revision 27
H8-E.1.32.DG; EEQ
- Limit Switch (NAMCO EA 180
-XX602 and EA18
0-XX402); Revision 6
H8-H; PINGP Environmental Specification; Revision 14
PJ9831; Purchase Order for RPM Automotive Grease Type
- EP1; 09/12/
97 SWI O-3; Safeguards Hold Cards & Component Blocking or Locking; Revision 89
WO 00313384; VMT: Refurb MV
-32075 Valve; 02/22/
16 WO 00362284; PM 32071PM 32071 11 Accumulator LP A Cold Leg Isolation MOV D70.1 PM; 07/22/
09 WO 00392372; MECH: MV
-32071 Stem Replacement and Repack; 11/06/
17 WO 00404615; PMRQ: 5663
-02 MV-32071 Accumulator L P A Cold Leg Isolation
MO VD70.1 PM; 11/19/
12 WO 00511621; ELEC: 31438
-LSCL, Replace EEQ Limit Switch per EC 27286; 01/11/20 18 WO 00529395; Repair MV
-32075 Due to Internal Leakage; 01/31/
18 WO 9506547; P32071 Remove/Reinstall Actuator & Votes MV
-32071; 02/14/
96 WO 9506592; Rebuild Spare Actuator for Use on MV
-32071; 09/17/
97 ENG-EQ-0111; EEQ File: ASCO NP8316 and NP8321 Solenoid Valves; 12/17/
18
ENG-EQ-0118; EEQ File: Raychem Splice Kits; 11/
6/20 18 H8-E.1.29.DG; EEQ
- ASCO Solenoid Valves; Revision 13
H8-E.1.47.DG; EEQ
- Motors and Heaters; Revision 5
H8-E.1.32.DG; EEQ
- Limit Switch (NAMCO EA180
-XX602 and EA180
-XX402); Revision 6
H8-E.1.33.DG; EEQ
- Limitorque Motors and Actuators (SMB/SB); Revision 9
PM 3124-1-12; 12 RHR Pump Inspection; Revision 24
PM 3124-4-12; 12 RHR Pump Motor Inspection (MTR 16
-6); Revision 2
D70.5; Motor Operated Valve Maintenance Procedure SMB
-00; Revision 1
D70.1; Motor Operated Valve Testing; Revision 24
D70.4; Motor Operated Valve Maintenance Procedure SMB
-000; Revision 1
D70.6; Motor Operated
Valve Maintenance Procedure SMB
-0; Revision 2
WO00521356; Replace SV
-33498; 12/16/
15 WO00532748; EQ Replacement
- Motor; 10/24/
16 WO00519587; 12 RHR Pump 18 Month Inspection; 01/31/
19 Maintenance Plan 10011996; PM 3124
-1-12 - 12 RHR PMP INSP; Revision N/A WO 700010495; MV
-32206 11 RHR HX to 11 SI PMP SUCT D70; 02/07/
18 CR501000003951; EEQ
- MV-32172 is not Qualified to Submerge; 10/18/
17 Corrective Actions Documents Generated as a Result of the Inspection
501000022512: EEQ DBAI: Editorial Error Identified; 01/29/
19 501000022562; EEQ DBAI: Question Using Regulatory Guide 1.183; 01/30/
19 501000022588; EEQ DBAI: H8
-E.1.33.DG Update Needed; 01/31/
19 501000022595; EEQ DBAI: H8
-E.1.33.DG Error; 01/31/
19 501000022610; EEQ DBAI: H8
-A Typo; 01/31/20 19 501000022633; EEQ DBAI: MOVLL Grease in MV
-32071; 02/01/
19 501000022667; EEQ DBAI: EQ File Submergence Evaluation
Issue; 02/01/
19 501000022680; EEQ DBAI: D70.7 and D70.11 Updates Needed; 02/01/
19 501000022723; EEQ DBAI: Limitorque
grease question; 02/04/
19 501000022828; EEQ DBAI: Editorial Error in Rad Evaluation;0 2/06/
19 501000023030; EEQ DBAI: Grease in Limitorque Doc Error; 02/11/
19 501000023042; EEQ DBAI: Humidity Evaluation Error; 02/11/
19 501000023058; EEQ DBAI
- EQ Review not Performed; 02/12/
19 501000023085; EEQ DBAI: Namco limit switch issue; 02/12/
19 501000023086; EEQ DBAI: Documentation Error; 02/12/
19 501000023091; FP
-SC-PE-05, Rev. 10 Enhancements; 02/12/
19 501000023102; EEQ DBAI: Shelf Life Question; 02/12/20 19 501000023162; EEQ DBAI: Oil Grading Criteria; 2/14/
19 501000023171; EQ Program not Discussed in CAP 01455269; 02/14/
19 501000023172; EEQ DBAI: Editorial Errors; 02/14/
19 501000022673; EEQ DBAI: EEQ Master List (EQML) Errors; 02/01/
19 501000022545; EEQ DBAI: EEQ File Documentation Error; 01/31/
19 501000023090; EEQ DBAI: EEQ File Documentation Issue; 02/19/
19 501000023131; EEQ DBAI: Missing Similarity Discussion; 02/13/
19 501000023141; EEQ DBAI: D70.1 Grease Grading Criteria; 02/13/
1 9