IR 05000483/2019011
| ML19326C811 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 11/22/2019 |
| From: | Vincent Gaddy Division of Nuclear Materials Safety IV |
| To: | Diya F Ameren Missouri |
| References | |
| IR 2019011 | |
| Download: ML19326C811 (15) | |
Text
ber 22, 2019
SUBJECT:
CALLAWAY PLANT - DESIGN BASIS ASSURANCE INSPECTION (PROGRAMS) INSPECTION REPORT 05000483/2019011
Dear Mr. Diya:
On November 7, 2019, the U.S. Nuclear Regulatory Commission (NRC) completed an inspection at Callaway Plant, 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.
One finding of very low safety significance (Green) is documented in this report. This finding involved a violation of NRC requirements. We are treating this violation as a non-cited violation (NCV) consistent with Section 2.3.2 of the Enforcement Policy.
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 IV; the Director, Office of Enforcement; and the NRC Resident Inspector at Callaway Plant. 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/
Vincent G. Gaddy, Chief Engineering Branch 1 Division of Reactor Safety Docket No. 05000483 License No. NPF-30
Enclosure:
As stated
Inspection Report
Docket Number: 05000483 License Number: NPF-30 Report Number: 05000483/2019011 Enterprise Identifier: I-2019-011-0011 Licensee: Ameren Missouri Facility: Callaway Plant Location: Steedman, MO Inspection Dates: October 21, 2019, to November 7, 2019 Inspectors: G. George, Senior Reactor Inspector D. Reinert, Reactor Inspector C. Stott, Reactor Inspector Approved By: Vincent G. Gaddy, Chief Engineering Branch 1 Division of Reactor Safety Enclosure
SUMMARY
The U.S. Nuclear Regulatory Commission (NRC) continued monitoring the licensees performance by conducting a design basis assurance inspection (programs) inspection at Callaway Plant in accordance with the Reactor Oversight Process. The Reactor Oversight Process is the NRCs program for overseeing the safe operation of commercial nuclear power reactors. Refer to https://www.nrc.gov/reactors/operating/oversight.html for more information.
List of Findings and Violations Failure to Environmentally Qualify Electrical Components in Containment to Most Severe Chemical Environment Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21N Systems NCV 05000483/2019011-01 Closed The inspectors identified a Green finding and associated non-cited violation of 10 CFR 50.49(e)(3) when the licensee failed to environmentally qualify all 10 CFR 50.49 electrical equipment for the most severe chemical effects expected in containment.
Additional Tracking Items None.
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
===71111.21N - Design Bases Assurance Inspection (Programs)
Select Sample Components to Review - Risk Significant/Low Design (Inside/Outside Containment) (IP Section 02.01) ===
- (1) Steam Generator Main Steam Isolation Valve B, ABHV0017
- (2) Auxiliary Building Residual Heat Removal Pump B Room Cooler, SGL10B
- (3) Containment Recirculation Sump A to Residual Heat Removal Pump A Isolation Valve, EJHV8811A
- (4) Auxiliary Relay Rack B Panel, RP 209
- (5) Component Cooling Water Heat Exchanger to Reactor Coolant Pump Header Flow Transmitter, EGFT0128
- (6) Chemical Volume and Control System Seal Water Injection Flow Transmitter, BGFT0215A
- (7) Air Supply Solenoid for Refueling Water Storage Tank to Fuel Pool Isolation Valve, BNHY8800A
- (8) Main Steam Loop 3 Steam Supply to Auxiliary Feedwater Pump Turbine Position Switch, ABZS0049 Select Sample Components to Review - Primary Containment (Inside Containment) (IP Section 02.01) (2 Samples)
- (1) Reactor Coolant System Pressurizer Safety Relief Valve Position Switch, BBZS8010A
- (2) Containment Fan Cooler Unit B and Inlet Air Temp Element, SGN01B and GNTE0063
INSPECTION RESULTS
Failure to Environmentally Qualify Electrical Components in Containment to Most Severe Chemical Environment Cornerstone Significance Cross-Cutting Report Aspect Section Mitigating Green None (NPP) 71111.21N Systems NCV 05000483/2019011-01 Closed The inspectors identified a Green finding and associated non-cited violation of 10 CFR 50.49(e)(3) when the licensee failed to environmentally qualify all 10 CFR 50.49 electrical equipment for the most severe chemical effects expected in containment.
Description:
The containment spray system functions to reduce pressure and temperature inside containment following a postulated loss of coolant accident or main steam line break and to remove radioactive fission products from the containment atmosphere. The containment spray system has two modes of operation. During the initial injection mode, the containment spray system draws borated water from the refueling water storage tank (RWST)and sprays it inside containment. After the RWST is depleted and the sprayed water has collected at the bottom of containment, the containment spray system transitions to its recirculation mode, drawing suction from containment sump and spraying the recirculated solution to continue scrubbing radioactive fission products.
In order to enhance the absorption of fission products following a loss of coolant accident, the original design of the containment spray system injection mode included a spray additive system. The spray additive system mixed the borated water from the RWST with a sodium hydroxide solution. The sodium hydroxide additive would raise the pH of the spray droplets to high levels during the injection mode (e.g., 9.3 to 11.0). The long-term equilibrium recirculation sump solution pH would remain greater than 8.5, which would ensure the absorbed radionuclides remain in solution and also minimize the potential for chloride-inducted stress corrosion cracking of any sprayed metallic components.
Industry studies performed subsequent to original plant design and construction demonstrated that fission product removal during the injection mode could be effectively performed by borated water spray alone, without using a sodium hydroxide additive.
Long-term radionuclide retention in the containment recirculation sump and minimization of stress-corrosion cracking could be assured so long as the recirculation sump pH was greater than 7.0. In 1994 the licensee received a license amendment to replace the spray additive system with a passive system consisting of stainless steel baskets containing trisodium phosphate (TSP) powder. With the new pH control methodology, the borated water sprayed during the injection mode collects at the containment sump and is neutralized by mixing with the TSP. The licensee calculated that the long term equilibrium recirculation sump solution pH would be in the range of 8.0 to 9.0.
During the inspection, the inspectors noted that the environmental qualification evaluations for all electrical components in containment only considered chemical sprays having a pH in the range of 8.5 to 11.0. After the plant modification that eliminated the spray additive system, the initial pH of the borated water spray during the injection mode could be as low as 4.0.
10 CFR 50.49(e)(3) and NUREG-0588, Interim Staff Position on Environmental Qualification of Safety-Related Electrical Equipment, Revision 1, Section 1.3, require that the electric equipment qualification program must be based on the composition of chemicals at least severe as that resulting from the most limiting mode of plant operation (e.g., containment spray, emergency core cooling, or recirculation from containment sump). Contrary to these standards, the licensee never qualified the electrical equipment located inside containment qualification for the full range of chemical system conditions the equipment is expected to see during both the injection and recirculation containment spray modes. Specifically, the licensee had never evaluated the chemical compatibility of the containment spray injection mode acidic borated water spray with any of the materials inside containment comprising the electrical equipment required to be environmentally qualified.
Corrective Actions: The licensee entered this issue into their corrective action program and performed an operability determination. The licensee performed vendor manual and literature searches to evaluate the compatibilities of known exposed materials with boric acid solutions. The licensee also gathered the initial acidic spray evaluations from two other nuclear utilities and reasonably determined that the components exposed to the borated water spray would remain capable of performing their safety function. The licensee plans to perform the required analysis or testing to demonstrate that all equipment that must conform to 10 CFR 50.49(e)(3) is qualified for the entire range of all containment spray conditions.
Corrective Action References: Condition Report 201906878
Performance Assessment:
Performance Deficiency: The failure to include the most severe composition of chemicals resulting from the most limiting mode of plant operation for components in the equipment qualification program in accordance with 10 CFR 50.49 (e)(3) was a performance deficiency.
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, this was a programmatic deficiency where the qualification basis for all equipment located inside containment does not account for the gap between the full range of expected environmental conditions (pH 4.0-11.0).
Significance: The inspectors assessed the significance of the finding using Appendix A, The Significance Determination Process (SDP) for Findings At-Power. The finding screens as having very low safety significance (Green) because it did not result in the loss of operability or functionality of mitigating systems. Specifically, the licensee reasonably determined the affected equipment will remain capable of performing its safety function based on evaluations of the same equipment and conditions at other nuclear power plants and from industry information addressing boric acid interaction with the affected materials.
Cross-Cutting Aspect: Not Present Performance. No cross-cutting aspect was assigned to this finding because the inspectors determined the finding did not reflect present licensee performance.
Enforcement:
Violation: Title 10 Code of Federal Regulations 50.49(e)(3) requires that the electric equipment qualification program must include and be based on the following:
- (3) Chemical effects. The composition of chemicals used must be at least as severe as that resulting from the most limiting mode of plant operation (e.g., containment spray, emergency core cooling, or recirculation from containment sump).
Contrary to the above, from 1994 to October 24, 2019, the licensees electric equipment qualification program failed to include and be based on the chemical effects of the most severe composition of chemicals resulting from the most limiting mode of plant operation.
Specifically, the most severe chemical composition expected inside containment could result from the containment spray injection mode. However, the qualification of electric equipment inside containment was based on the chemical composition of the containment spray recirculation mode, which was less severe due to the borated water from the injection mode being neutralized by the trisodium phosphate located inside of containment.
Enforcement Action: This violation is being treated as a non-cited violation, consistent with Section 2.3.2 of the Enforcement Policy.
EXIT MEETINGS AND DEBRIEFS
The inspectors verified no proprietary information was retained or documented in this report.
- On November 7, 2019, the inspectors presented the design basis assurance (programs)inspection results to Mr. F. Diya, Senior Vice President and Chief Nuclear Officer, and other members of the licensee staff.
DOCUMENTS REVIEWED
Inspection Type Designation Description or Title Revision or
Procedure Date
71111.21N Calculations CN-CRA-04-39 Callaway Main Steam Tunnel MSLB Equipment Thermal Lag 0
Calculation with GOTHIC
J-27G03- Stress Analysis of Instrument Lines System: As-built tube 0
HVC8800A run for SFR 2-YY-016D
J-G03-AO Stress Analysis of Instrument Lines System: Westinghouse 0
Control Valves and Accessories - Auxiliary Building
J-G03-AS Stress Analysis of Instrument Lines: Westinghouse Control 0
Valves and Accessories - Auxiliary Building
NAI-2052-001 Callaway Energy Center Auxiliary Building GOTHIC Model 0
ZZ-443 SBLOCA Temperature and Pressure Analysis with Reduced 1
Heat Sinks
ZZ-524 Main Steam Tunnel Temperature Response to a Main Steam 0
Line Break Outside Containment
ZZ-525 LOCA and MSLB Containment Pressure and Temperature 2
Response
Corrective Action Condition Reports 201302563, 201506803, 201600527, 201600100,
Documents 201806334, 201901444
Corrective Action Condition Reports 201906793, 201906810, 201906847, 201906878,
Documents 201906960, 201906963, 201907049, 201907111,
Resulting from 201907119, 201907147, 201907157, 201907166,
Inspection 201907169, 201906847
Drawings 1D99954 Motor Operated Gate Valve - Model 14002GM84FEHOEO 5
E-093-00045 Auxiliary Relay Rack Arrangement 13
E-23-AB17(Q) Steam Warmup to Auxiliary Feedwater Pump Turbine 8
E-23AB17(Q) Schematic Diagram Steam Warmup to Auxiliary Feedwater 8
Pump Turbine
E-23AB28(Q) Main Steam Isolation Valves Control 11
E-23EJ06A(Q) Sump to No. 1 Residual Heat Removal Pump 15
E-2R8900 Raceway Notes, Symbols, and Details 107
J-07G03 Hanger Design 0
J-27D22(Q) Instrument Mounting Detail D.P. Transmitter 10
J-27G03(Q), Sh. Installation Details Westinghouse Control Valve Accessories 4
Inspection Type Designation Description or Title Revision or
Procedure Date
J-601A-00096 Control Valve 1" Model 38-20761-6A1 ANSI Class 1500 Sch. 14
Socket Weld Ends No. 9 Reverse Actuator 6A1 Side
Mounted Handwheel
M-22AB02(Q) Piping and Instrumentation Diagram Main Steam Piping 18
M-22EJ01(Q) Piping and Instrumentation Diagram Residual Heat Removal 62
System
M-22GL02(Q) Piping and Instrumentation Diagram Auxiliary Building HVAC 27
M-628-00086 Solenoid Valve 1-4 Assembly Drawing 0
M-628-00087 Solenoid Valve 5+6 Assembly Drawing 0
M-628-00094 System Medium Operated Actuator for Quick Closing Valve 1
Layout Diagram
Engineering CMP 92-1053 Replace current spray additive system with a recirculating 06/28/1994
Changes fluid pH control system utilizing trisodium phosphate-
dodecahydrate (TSP-C)
MP 08-0054 Pressurizer Pressure Transmitter Replacement 000.1
MP 18-0070 Atmospheric Steam Dump (ASD) Transducer Thermo-Wrap 3
Modification Request
Engineering CR 201901444- Rosemount Transmitter Qualified Life Calculations 04/09/2019
Evaluations 006
RFR 07461A ASCO SOV/Namco Switch Sealing 04/06/1990
RFR 07461B Evaluation of Thermal Insulator for Namco Quick 04/27/1990
Disconnects used in Area 5
Miscellaneous 10466-E-062- Prototype Test Doc. BIW Cable Sys. Inc. 02/22/1983
0003-05
E-025-00006 Qualification Type Test Report for Limitorque Valve 1
Actuators with Type LR Motor
E-025-00006G01 Limitorque Valve Operator Generic Qualification Evaluation 3
E-025-00006P01 Limitorque Motor Operator Plant Qualification Evaluation 5
E-025-00008 Qualification Type Test Report Multi-Point Terminal Strips 1
E-025-00008G01 Limitorque Terminal Block Generic Qualification Evaluation 2
E-025-00008P01 Buchanan, Marathon, GE, Curtis Terminal Block Plant 4
Qualification Evaluation
E-025-00014 Tests of Raychem Flamtrol 0
Inspection Type Designation Description or Title Revision or
Procedure Date
E-025-00014G01 Raychem Cable Generic Qualification Evaluation 1
E-025-00014P01 Raychem Cable Plant Qualification Evaluation 3
E-035-00153 BIW Cable Systems, Inc. 0
E-1032-00010 Qualification Test Report for NAMCO Series EA180 Limit 0
Switches
E-1032- Namco Controls Limit Switch 1
00010G01
E-1032- Namco Controls Limit Switch 5
00010P01
E-1032- Namco Controls Limit Switch 1
00018G01
E-1032- Namco Controls Limit Switch 1
00018G01
E-1032- Namco Controls Limit Switch/ECSA/SEALANT 7
00018P01
E-21012 Bill of Materials, Auxiliary Relay Rack 21
E-21013AAG01 Raychem (Tyco Electronics-Energy) Splice 0
E-21013AAP01 Raychem (Tyco Electronics-Energy) Splice 5
E-21013C Test Report for EGS GRAY Boot Connectors Models GB-1, 1
GB-2, &GB-3
E-21013CG01 EGS Connectors Generic Qualification Evaluation 2
E-21013CP01 EGS Corp. Connectors Plant Qualification Evaluation 6
E-21013XG01 Raychem Corporation Splice Generic Qualification 2
Evaluation
E-21013XG01 Raychem Corporation Splice 2
E-21013XP01 Raychem Splice 7
E-21013XP01 Raychem Splice Plant Qualification Evaluation 7
EDR-5336 Nuclear Products Requalification Testing 5
EDR-5336 Nulcear Products Requalification Testing 5
EQ CN 90-17 Downgrade MSIV, MFIV, and Various Area 5 J-601A 07/06/1990
NAMCO Limit Switches and the SG Chemical Addition
Valves to Category C
EQCN 02-01 Revise the Qualified Lives of the Rosemount 1153 Series B 01/08/2002
Transmitters Located in the Auxiliary Building
Inspection Type Designation Description or Title Revision or
Procedure Date
FSAR CN 88-58 Update FSAR to Incorporate Results of Reviews of MSLBs 11/28/1988
Outside Containment with Superheated Steam Releases, IN 84-90
FSAR CN 89-21 Change the Environmental Classification of the MSIV & 05/04/1989
MFIV 10% Exercise Limit Switches
FSAR CN 90-36 Change LOCA Category for all Area 5 NAMCO Limit 06/15/1990
Switches and Associated Teminal Boxes to C. Change
MSLB Category for These Components to C
J-301-00064 Qualifications Report for Pressure Transmitters Rosemount J
Model 1153 Series B Rosemount Report 108025
J-301-00065-02 Type Test Report for Pressure Transmitters, Rosemount A
Model 1153 Series B, Rosemount Report 108026
J-301-00065G01 Rosemount Pressure Transmitters 2
J-301-00065P01 Rosemount Transmitter 2
J-301-00067 Model 1153 Series B Alphaline Pressure Transmitter for 23
Nuclear Service
J-301-0085-01 Qualification Report For Pressure Transmitters Rosemount A
Model 1153 Series D Rosemount Report D8300040
M-237-00191 ASCO Qualification Test Report AQR-6768 1
M-237-00191G01 Automatic Switch Company, Solenoid Valve 4
M-237-00191P01 Automatic Switch Company, Solenoid Valve 9
M-612-00062 IM Air Handling Units (Room Coolers) Carrier Corporation 23
M-612-00087 Room Coolers - Class 1E Medium AC Motors (Outside 2
Containment)
M-612-00087G01 Carrier/Westinghouse Motor Generic Qualification Evaluation 1
M-612-00087P01 Carrier/Westinghouse Area Room Coolers Plant 1
Qualification Evaluation
M-612-00119 Westinghouse Replacement Motor Design Data and Seismic 0
Evaluation for DSGL09A&B, DSGL10B, DSGL13A and
DSGF02A&B
M-619.3- Joy Manufacturing Co. Motor Generic Qualification 5/7/2005
00007G01 Evaluation
M-619.3- Joy Manufacturing Co. Motor Plant Qualification Evaluation 7/27/2015
00007P01
Inspection Type Designation Description or Title Revision or
Procedure Date
M-619.3-0007-06 Joy Qualification Test Report 3/8/83
M-628-00077 IM for MSIV Actuator CCI Manufactured APS-700 4
M-630-00097 Nuclear Environmental & Seismic Qualification Test Report 0
for Control Components, Inc. Solenoid Valves
M-630-00097G01 Control Components, Inc. Solenoid Valve Generic 2
Qualification Evaluation
M-630-00097P01 Controlled Components, Inc. (CCI) Solenoid Valve Plant 6
Qualification Evaluation
M-724-00409 Westinghouse Instruction Book for Motor Operated Gate 1
Valves, Manually Operated Gate Valves & Swing Check
Valves for SNUPPS Project
MPM-ZZ-QA001 Limitorque Actuator Inspection and Lubrication 49
QR-065- Qualification Report for Current to Pressure Transducer 2
351021043-01 Thermo Scientific P/N: STD6131-2
S-1027- Patel/EGS Connectors Generic Qualification Evaluation 05/16/2005
00013G01
S-1027- Patel/EGS Connectors Plant Qualification Evaluation 10/15/2014
00013P01
S-1027- EGS Corp. Sealant Generic Qualification Evaluation 0
00023G01
Procedures APA-ZZ-00304 Control of Callaway Equipment List 44
APA-ZZ-00420 Traceability and Accountability of Safety Related and Special 16
Scope Material and Equipment After Issue
EA189 90051 Namco Controls Maintenance Instructions for Type EA180 B
Switch
EA189-90006 Namco Controls Installation Instructions for EA180 Nuclear 01/23/1980
Switch - Silicone Gaskets
EADS02-E Namco Controls Product Data Bulletin for Limit 12/01/2002
Switches/Receptacle Assembly for Nuclear Environments
EDP-ZZ-04054 Conduct of Equipment Seismic Qualification Activities 7
EDP-ZZ-04054 Product of Equipment Seismic Qualification Activities 7
ITL-BG-215A RCP's Seal Injection Flow 8
MPM-AB-QV001 Mainsteam Isolation Valve Actuator Overhaul 32
MPM-ZZ-QV021 FWIV and MSIV Solenoid Valve Overhaul 1
Inspection Type Designation Description or Title Revision or
Procedure Date
MTM-ZZ-QA008 Limitorque SB-1 MOV Inspection and Overhaul 8
WDP-ZZ-00010 Identification, Control, Storage, and Disposition of Shelf Life 19
Items
WSP-ZZ-00002 Storeroom Storage and Control 30
Self-Assessments 201309684-07 Self-Assessment Topic: Environmental Qualification 08/26/2014
Program
FSA-201900029- Environmental Qualification (EQ) Program Pre-Inspection 03/28/2019
006 Self Assessment
Work Orders Work Orders 140506855.500, 14506428.500, 18004612.600, E489594,
W471043
2