ML24059A063
| ML24059A063 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 03/15/2024 |
| From: | Hipolito Gonzalez Plant Licensing Branch 1 |
| To: | Rhoades D Constellation Energy Generation, Constellation Nuclear |
| Goetz, S | |
| Shared Package | |
| ML24059A089 | List: |
| References | |
| EPID L-2023-LLR-0006 | |
| Download: ML24059A063 (1) | |
Text
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION ENCLOSURE 2 (NON-PROPRIETARY)
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO RELIEF REQUEST NO.ISI05021 RENEWED FACILITY OPERATING LICENSE NOS. DPR-53 AND DPR-69 CALVERT CLIFFS NUCLEAR POWER PLANT, UNITS 1 AND 2 DOCKET NOS. 50317 AND 50318 Proprietary information pursuant to Section 2.390 of Title 10 of the Code of Federal Regulations has been redacted from this document.
Redacted information is identified by blank space enclosed within (( double brackets )).
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY PROPRIETARY INFORMATION SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUEST NO. ISI-05-021 CONSTELLATION ENERGY GENERATION, LLC CALVERT CLIFFS NUCLEAR POWER PLANT, UNITS 1 AND 2 DOCKET NOS. 50-317 AND 50-318
1.0 INTRODUCTION
By letter dated February 24, 2023 (Agencywide Documents Access and Management System Accession No. ML23055A284), as supplemented by letters dated August 29, 2023 (ML23241A840), and January 11, 2024 (ML24011A073),1 Constellation Energy Generation, LLC (the licensee) submitted Relief Request No. ISI-05-021 (a proposed alternative) to the U.S. Nuclear Regulatory Commission (NRC) for Calvert Cliffs Nuclear Power Plant, Units 1 and 2 (Calvert Cliffs). Pursuant to Title 10 of the Code of Federal Regulations (10 CFR), Section 50.55a(z)(1), the licensee proposed to use an alternative to certain American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code) requirements for the fifth 10-year inservice inspection interval, which will end on June 30, 2029, on the basis that the alternative provides an acceptable level of quality and safety. The licensee proposed to proactively repair the supply and return saltwater system piping using a carbon fiber-reinforced polymer (CFRP) composite system.
2.0 REGULATORY EVALUATION
2.1 Regulations The NRC regulations in 10 CFR 50.55a(g)(4), Inservice inspection standards requirement for operating plants, state, in part, that ASME Code Class 1, 2, and 3, components including supports shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components.
The NRC regulations in 10 CFR 50.55a(z), Alternative to codes and standards requirements, state that Alternatives to the requirements of paragraphs (b) through (h) of [10 CFR 50.55a] or portions thereof may be used when authorized by the Director, Office of Nuclear Reactor Regulation. A proposed alternative must be submitted and authorized prior to implementation.
The licensee must demonstrate that its request meets one of two criteria: (a) the proposed alternative would provide an acceptable level of quality and safety in accordance with 10 CFR 50.55a(z)(1); or (b) compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety in accordance with 10 CFR 50.55a(z)(2). The licensee has submitted the request on 1
The submittal and supplements contained proprietary information. The proprietary portions are not publicly available.
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION the basis that the proposed alternative would provide an acceptable level of quality and safety in accordance with 10 CFR 50.55a(z)(1).
2.2 Licensees Request ASME Code Component Affected The ASME Code components affected by the licensees proposed alternative are the safety-related supply and return saltwater system piping that are buried and classified as ASME Code Class 3 with diameters of 30 inches and 36 inches, and straight run lines with minimal fittings.
Sections 4.a.i and ii of enclosure 1 to the submittal describe the affected supply and return saltwater piping as follows:
The safety-related supply and return saltwater piping are buried and classified as ASME Code Class 3 with diameters of 30 inches and 36 inches, straight run lines, and minimal fittings.
The material of construction of the saltwater piping and fittings is ductile cast iron that is joined with bell and spigot.
The interior surface of the saltwater piping is lined with cement mortar.
The exterior surface of the saltwater piping is coated.
The saltwater piping does not have cathodic protection.
The CFRP repair does not include any pumps, valves, expansion joints, or threaded connections.
In its submittal, the licensee stated that the saltwater system piping moves Chesapeake Bay salt water from the intake structure, through the system and back to the circulating water discharge conduits. The saltwater system piping included in the licensees request is safety-related and consists of two subsystems in each unit. Each subsystem provides salt water to the service water heat exchangers, component cooling water heat exchangers, and the emergency core cooling system pump room air cooler to transfer heat from those systems to the Chesapeake Bay. Seal water for the circulating water pumps is supplied by both subsystems. A self-cleaning strainer is installed upstream of each service water heat exchanger.
ASME Code Edition and Requirements The code of record for the fifth 10-year inservice inspection interval is the 2013 Edition of the ASME Code,Section XI.
ASME Code, Section Xl, Article IWA-4000, Repair/Replacement Activities, paragraph IWA-4221, Construction Code and Owners Requirements, subparagraph IWA-4221(b), states, An item to be used for repair/replacement activities shall meet the Construction Code specified in accordance with [subparagraphs IWA-4221(b)(1), IWA-4221(b)(2), or IWA-4221(b)(3)].
Subparagraph IWA-4221(b)(1) states, When replacing an existing item, the new item shall meet the Construction Code to which the original item was constructed.
The original construction code for the applicable piping and components is the 1967 Edition of the United States of America Standards (USAS) B31.1.0-1967, Power Piping, as
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION supplemented by the requirements of American National Standards Institute (ANSI) A21.1-1967/American Water Works Association (AWWA) C101-67, Standard for Thickness Design of Cast Iron Pipe, and ANSI A21.50-1976 (AWWA C150-1976), American National Standard for the Thickness Design of Ductile-Iron Pipe. 2 Duration of the Alternative The licensee requested approval of this alternative for the fifth 10-year inservice inspection interval, which began on July 1, 2019, and is scheduled to end on June 30, 2029.
Licensees Proposed Alternative The licensee proposed to proactively repair the supply and return saltwater system piping by the CFRP composite system as an alternative to the requirements in ASME Code,Section XI, subparagraph IWA-4221(b)(1). In its submittal, the licensee indicated that the CFRP composite is comprised of layers of high strength carbon fiber fabric and glass fiber fabric that are fully saturated in a two-part 100 percent solids epoxy matrix and bonded to the inside diameter (ID) surface of the existing saltwater pipe. The installed CFRP composite will form a structural lining within the saltwater pipe, perform as a standalone system, replace the existing pipe except at the terminal ends of the CFRP, and resist all design loading without reliance on the host pipe for the service life of the repair which is 50 years.
The licensee stated in its submittal that the CFRP composite for repair of the buried ASME Code Class 3 piping is a recent repair technique. The ASME Code,Section XI and Section III, Rules for Constructions of Nuclear Facility Components, NRC-approved code cases, and the construction code do not have any provisions for using the CFRP composite.
Enclosures 1 through 9 of the submittal, as supplemented, provides the licensees technical basis for use of the proposed CFRP composite system which includes design, manufacturing, materials qualification, materials testing, installation, inspection, and quality control. In addition, the NRC previously authorized similar alternative requests for use of the CFRP composite system for internal repair of the buried ASME Code Class 3 service water piping in Surry Power Station (ML17303A068), South Texas Project (ML20227A385), Arkansas Nuclear One (ML21188A022), and Brunswick Steam Electric Plant (ML21343A200).
3.0 TECHNICAL EVALUATION
The NRC staff has evaluated the licensees submittal pursuant to 10 CFR 50.55a(z)(1). The NRC staffs evaluation focused on whether the proposed alternative provides an acceptable level of quality and safety.
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2 USAS B31.1.0 later became ANSI B31.1 and ASME B31.1.
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The licensees submittal also described the inservice inspection of the repaired saltwater system supply and return piping. The licensee explained that any inspections or repair/replacement of the CFRP composite will be conducted in accordance with the applicable edition of the ASME Code,Section XI, or alternative thereto, at the time of the repair/replacement or inspection.
The NRC staff finds that the licensee adequately identified the important technical areas for the application of the CFRP composite system and provided related information, as further evaluated below.
3.1 Design Basis Attachment A of enclosure 5 of the submittal describes the design basis for the CFRP composite system, including the objectives, approach, methodologies, applicable standards, technical criteria, loads, load combinations, applicable design factors and effective safety factors of the design for the CFRP system design. The various aspects of the design criteria are grouped into strength, reliability, durability, and design approach, as discussed in this section.
The design loads and limit states are evaluated in section 3.2.
3.1.1 Strength
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The NRC staff finds that the licensees approach discussed above is acceptable because
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3.1.2 Reliability
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3.1.3 Durability
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3.1.4 Design Approach
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3.2 Design Loads and Limit States As noted in attachment B of enclosure 5 of the licensees submittal dated February 24, 2023, the CFRP system is designed to resist the effects of pipe and fluid weights, internal pressure, transient pressure, vacuum pressure, external ground water pressure, earth loads, surface live loads and temperature differentials. The buried section of the piping is restrained by the thrust blocks at every bend that are connected to the turbine building and intake structure. The entirety of the buried piping is anticipated to experience only rigid body movement with the turbine building foundation and not experience any differential displacement due to seismic loading. It is also noted that the original design of buried piping did not consider seismic loading.
The CFRP composite system design layup, for both 30-inch and 36-inch diameter saltwater piping at Calvert Cliffs, consists of ((
))
The subject host piping features the following:
Nominal 36 pipe: outside diameter and wall thickness: 38.3 by 0.63 Nominal 30 pipe: outside diameter and wall thickness: 32 by 0.55 Ovality: 3 percent Material: ASTM A-377/ANSI A21.51 (AWWA C151) ductile iron with small sections of ANSI A21.6 gray cast iron There are five 30 lines and two 36 lines in each unit.
The loadings consist of the following:
Pressure Design pressure for saltwater piping: 50 pounds per square inch (psi)
Transient Pressure: 0 psi Vacuum Pressure: -1 psi Temperature Maximum operating temperature:
Supply lines: 32 °F to 90 °F Return lines: less than (<) 100 °F Thermal Loads: range from 32 °F to 121 °F
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Design temperature: 121 °F
CFRP Installation temperature: 71 °F to 82 °F
Soil temperature: 50 °F to 70 °F
Temperature differential (T): plus or minus (+/-) 50 °F
Regarding pressure-induced thrust, because of the presence of thrust blocks at each bend location, pressure induced thrust is not required in the design.
External Loads
Soil cover height
For saltwater piping, the soil cover varies between 1.5 feet to 10.5 feet.
Conservatively enveloped values were used in the analysis.
For 30 lines, the soil cover height was considered to be 10.5 feet.
For 36 lines, the soil cover height was considered to be 1.5 feet.
Groundwater height above top of the pipe
Groundwater height varies between 0.5 feet and 9.5 feet.
Analysis uses conservatively enveloped values.
For 30 lines, groundwater height was considered to be 9.5 feet
For 36 lines, groundwater height was considered to be 0.5 ft.
Regarding surface live loads, the buried pipelines are buried under a reinforced concrete slab, which resists the live loads above the slab. Therefore, no surface live loads act on the buried pipe.
Differential settlement was considered negligible.
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3.2.1 Load Combinations for Design Limit States As discussed in attachment C of enclosure 5 to the submittal, the licensee considered the following loads for the design limit states: internal working pressure, internal transient pressure, external groundwater pressure, internal negative pressure (vacuum), and temperature differential between CFRP system installation temperature and maximum and minimum operating temperature, gravity loads, soil loads, and seismic loading.
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Load Designation Symbols Pw: internal working pressure, with thrust as applicable Pt:
internal transient pressure, with thrust as applicable Pv: internal negative pressure (vacuum)
T: temperature differential between CFRP average installation temperature and maximum/minimum operating temperature We: earth load We*: earth load in submerged condition when groundwater is present Wp: pipe weight Wp*: pipe weight in submerged condition when groundwater is present Pgw: external groundwater pressure Wt: surface live load Wf: fluid weight Fpw: thrust effect from working pressure Fpt: thrust effect from transient pressure E:
seismic load
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In its supplement dated August 29, 2023, regarding glass transition temperature (Tg) affected by cure temperature, the licensee provided information that V-WrapTM 770 epoxy remains in the glassy phase using the criterion ((
)) This ensures that the CFRP repair will not become rubbery at the maximum operating temperature of 121 °F and, therefore, will maintain load carrying capability and structural integrity. ((
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The NRC staff finds that the licensees calculations have considered the appropriate load combinations in analyzing the repaired 30-inch diameter piping. The licensee used results from the Water Research Foundations research program, which is primarily developed for nonsafety-related applications. These included full-scale field experiments of PCCP subjected to the combined effects of internal pressure and external loads to study modes and loads at failure, laboratory scale experiments to determine shear bond strength, and development of simplified and reliable design formulas.
The research program also included an investigation using finite element analysis of CFRP-lined buried PCCP to analyze the combined effects of gravity loads and pressures to validate the accuracy and conservatism of simplified design formulas for limit states including pressure, bending, and stability (buckling). In such analyses, stresses in the CFRP system and its buckling load resulting from interaction of the CFRP system, host pipe, and surrounding soil were calculated as the host pipe continues to degrade during its service life.
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((
)) Based on the additional layers provided at the discontinuities, the NRC staff concludes that there is additional margin of safety in the design.
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The NRC staff concludes that the licensee has performed an acceptable failure modes and effects analysis (FMEA) because the licensee has considered significant potential failure modes and demonstrated that the CFRP system is designed to mitigate or prevent the potential failures.
The CFRP has been used in aerospace, automotive, marine, and sports industries because of its advantage of high strength combined with low weight. However, NRC regulations do not currently address the AWWA guidance. Therefore, the NRC staff evaluated the proposed alternative based on the merits of its technical basis in lieu of the AWWA guidance or the draft ASME Code Case N-871, Internal Repair of Class 2 and 3 Buried Piping Using Carbon Fiber-Reinforced Polymer Composite, which is under development.
Terminations
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3.2.4 Factor of Safety (Allowable Stress Design versus LRFD)
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Allowable Stress Design Methodology in ASME Code, Subsection NC/ND Classes 2 and 3 References used for the following discussion include the 2017 Editions of: (1) ASME Code,Section III, Subsection ND, Class 3 Components; (2) ASME Code,Section II, Materials, Part D, Properties, Mandatory Appendix 1, Basis for Establishing Stress Values in Tables 1A and 1B, and Mandatory Appendix 3, Basis for Establishing External Pressure Charts; and (3) ASME Code,Section VIII, Rules for Construction of Pressure Vessels, Division 1, Nonmandatory Appendix P, Basis for Establishing Allowable Stress Values for UCI, UCD, and ULT Materials.
In the ASME Code, the factor of safety for ductile materials (metallic) had a value of 4 until 1999, when it was reduced to 3.5. This is primarily used to determine the minimum required wall thickness based on hoop-stress considerations under internal pressure. The factor of safety is applied to the minimum tensile strength at temperature (Su) to obtain allowable stress equaling Su/4 or Su/3.5). Furthermore, there are k factors (1.0, 1.2, 1.8, and 2.4) applied to increase the allowable stress for other load combinations (design-normal, upset, emergency, and faulted, or service levels A, B, C, and D). In 1981, the k factors were changed to 1.5, 1.65, 2.25, and 3 (with other limitations). For secondary stresses such as thermal expansion, the k factor is approximately 1.5 (i.e., 1.25 applied to Sc + 0.25 applied to Sh, where Sc and Sh are allowable stresses at cold and hot conditions, respectively). Thus, k factors effectively lower the factor of safety in the ASME ASD methodology. In the ASME Code, the factor of safety for brittle metals (e.g., cast iron) is 10.
For buckling, the factor of safety values are as follows: FS (factor of safety) of 3 and a k factor of 4/3. The FSeff is the effective factor of safety for buckling and is calculated as follows:
FSeff = FS/k (or 3/(4/3)), which equals 2.25 for longitudinal buckling.
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION For buckling of ASME safety related buried piping in circumferential direction, the factor of safety recommended in equation 5.11 of NUREG/CR-6876, Probabilistic Dose Analysis Using Parameter Distributions Developed for RESRAD and RESRAD-BUILD Codes (ML003741920),
should be used. For safety Classes 2 and 3, a factor of safety of 2.5 (when H/D 2) and a factor of safety of 3.0 (when H/D < 2) should be used, where H/D is ratio of soil cover above pipe (H) to pipe diameter (D). The factor of safety of 2 in AWWA M-11 is for non-nuclear applications.
The higher factor of safety noted above in NUREG/CR-6876 (equation 5.11) is also recommended in Buried Pipe Design (chapter 3, page 112),4 and American Lifeline Alliance report, Guidelines for the Design of Buried Steel Pipe (section 4.2-4).5 The following table summarizes the acceptable calculated ASD methodology values.
ASD Methodology Summary:
Computed/Allowable less than or equal to 1 or Allowable/Computed greater than (>) 1 Values Through 1981 Codes Prior to 1999 With FS = 4 (Ductile)
Codes After 1999 With FS = 3.5 (Ductile)
With FS = 10 (Brittle)
Longitudinal (Rows 37)
FSeff FSeff FSeff Normal (Level-A) k = 1 4
3.5 10 Upset (Level-B) k = 1.2 3.33 2.92 8.33 Emergency (Level-C) k = 1.8 2.22 1.94 5.56 Faulted (Level-D) k = 2.4 1.67 1.46 4.17 Thermal Stresses (if 7,000 cycles) 1.5Sh approximately (1.25Sc + 0.25Sh) 2.67 2.33 6.67 Hoop Direction 4
3.5 10 Values After 1981 With FS = 4 (Ductile)
With FS = 3.5 (Ductile)
With FS = 10 (Brittle)
Longitudinal (Rows 37)
FSeff FSeff FSeff Normal (Level-A) k = 1.5 2.67 2.33 6.67 Upset (Level-B) k = 1.8 2.22 1.94 5.56 Emergency (Level-C) k = 2.25 1.78 1.56 4.44 Faulted (Level-D) k = 3 1.33 1.17 3.33 Thermal Stresses (if 7,000 cycles) 1.5Sh 2.67 2.33 6.67 Hoop Direction 4
3.5 10 4
Moser, A. P., and Steven Folkman. 2008. Buried Pipe Design. 3rd ed. New York 5
American Lifeline Alliance (American Society of Civil Engineers), Guidelines for the Design of Buried Steel Pipe, July 2001 (with addenda through February 2005)
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION 3.2.5 LRFD Methodology Used for Repair of Saltwater Piping Using CFRP For the LRFD methodology acceptability, the load must be less than or equal to () the resistance, the demand the capacity, or the demand the strength.
The CFRP material is a nonisotropic, linearly elastic, high-strength composite with very low rupture strain of approximately 1 percent (brittle) compared to 15 to 20 percent for ductile metals like steel. An ASME Code Case currently under development for CFRP, as well as in a few published papers using CFRP, utilize a factor of safety of 10 for the ASD methodology, while it varies for the LRFD methodology. The LRFD methodology applies four types of factors, namely:
load factor (LF), resistance factor () for material strength variability, material adjustment factor (C) for environmental exposure, and a time effect factor () that depends on short-term or long-term use.
A load factor of greater than (>) 1 is applied to the left-hand side of the LRFD evaluations (i.e., load or demand) to increase the load for uncertainties, while factors, C, and < 1 are applied to the right-hand side of the LRFD evaluations (i.e., resistance or strength) to reduce allowable strength. The following table summarizes the load factors, resistance factors, material adjustment factor, and time effect factors used by the licensee in its evaluations.
((
)) These correspond to the current ASME Code factor of safety of 3.5 for stresses and 3.0 for buckling and are considered reasonable for Calvert Cliffs conditions and water environments. Those portions of saltwater pipes to be repaired using CFRP are buried and experience gravity load; internal and external pressure and thermal loading; and ground water, thermal, and soil overburden loads.
OFFICIAL USE ONLY - PROPRIETARY INFORMATION OFFICIAL USE ONLY - PROPRIETARY INFORMATION The following table shows the minimum acceptable FSeff for the LRFD methodology for different load combinations or limit states:
Safety Factors for Load Combinations
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3.2.6 Results of Effective Factors of Safety for End Use and Their Acceptability For degraded ductile iron piping, the saltwater system safety-related buried 30-inch and 36-inch diameter piping will be repaired using CFRP composite. The following tables summarize the results of FSeff. ((
Index Piping Soil Cover (feet) (H)
Groundwater Height (feet) 1 Saltwater 36 piping Outside Diameter, D = 38.3 for 36 pipe 1.5 0.5 2
Saltwater 30 piping Outside Diameter, D = 32 for 30 pipe 1.5 to 10.5 0.5 to 9.5 For H = 1.5 feet of soil cover, H/D = 0.47 for 36 pipe, and H/D = 0.56 for 30 pipe. For H/D < 2, minimum acceptable factor of safety for ((
)) is 3.0.
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In summary, all limit states are satisfied with a cure adjustment factor corresponding to minimum cure temperature of 90 °F used conservatively in design. Based on a review of licensees design check, the results of FSeff remain acceptable, ((
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The NRC staff finds that the FSeff for short-term use will be higher compared to long-term (end-use) because time effect factor is 1.0 for short-term use. Therefore, FSeff for short-term use are acceptable. This is because the time effect factor for short-term strength is 1.0, while it is a reduction factor of 0.6 for the long-term end-use condition.
Based on the NRC staffs review of the licensees calculations, as described above, the NRC staff finds that the CFRP system design described in the alternative request satisfies the acceptance criteria for the applicable limit states. Therefore, the NRC finds that there is reasonable assurance that the proposed repair of degraded saltwater system using CFRP composite, including the terminations overlapping with the host piping, will maintain structural integrity. The design evaluations are acceptable because the ((
)) meets the limiting values for all limit states and, therefore, meets the acceptance criteria. The NRC staff concludes that the CFRP design used for the repair of degraded saltwater supply piping is acceptable.
3.2.7 Failure Modes and Effects Analysis The NRC staff concludes that the licensee has performed an adequate FMEA because the licensee has considered potential credible failure modes of the installed CFRP layers, discussed the basis of why the failure mode is not possible, and provided solutions to either prevent or minimize the failure modes. Therefore, the NRC staff finds that the licensees FMEA is acceptable.
The NRC staff finds that the proposed CFRP composite satisfies the design criteria of the subject piping such that the CFRP layers will be able to support the existing pipe loads without considering the host pipe base metal, except at the terminations. The CFRP terminations act as interfaces to transfer loads from the repaired sections to the host pipe. The NRC staff concludes that the terminations are adequately designed to maintain their structural integrity.
3.3 Evaluation of Material to the submittal describes requirements for material manufacturing and qualification of the CFRP composite system. The licensee uses commercial grade items (CGI) and manufacturing that require both CGI dedication and qualification in accordance with ASME Nuclear Quality Assurance (NQA)-1, Quality Assurance Requirements for Nuclear Facility Applications, and 10 CFR Part 50, Appendix B, Quality Assurance Criteria for Nuclear Power Plants and Fuel Reprocessing Plants. The NRC staffs evaluation focuses on the licensees material manufacturing processes that include material acceptance, material qualification, and watertightness demonstration.
3.3.1 Evaluation of Material Manufacturing The CFRP composite system includes unidirectional carbon fiber fabrics, bidirectional glass fiber fabrics, two-part epoxy, ((
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Based on the above, the NRC staff finds that the licensee adequately described the materials, components, and their properties or attributes of importance for design and fabrication of the CFRP composite system.
As required by ASME NQA-1 and 10 CFR Part 50, Appendix B, controls shall be in place to ensure that the correct safety related items are specified and accepted. To meet the requirements, the licensee will perform CGI procurement control and CGI dedication. The NRC staffs evaluation of these activities are as follows.
As part of its CGI procurement control activities, ((
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)) The NRC staff finds that the licensees CGI controls are adequate and consistent with the requirements.
As part of its CGI dedication activities, the licensee utilizes the industry guidance and methodology in Electric Power Research Institute (EPRI) technical report (TR), Plant Engineering: Guideline for Acceptance of Commercial-Grade Items in Nuclear Safety-Related Applications, Revision 1 to EPRI NP-5652 and TR-102260, dated September 2014, and EPRI TR-017218-R1, Guideline for Sampling in the Commercial-Grade Item Acceptance Process, dated February 23, 1999, to perform the required CGI-specific technical evaluation. ((
)) The NRC staff finds the licensees CGI dedication is adequate and consistent with the requirements.
Therefore, the NRC staff finds that the licensees CGI control and dedication of the CFRP composite system is acceptable because: (1) the licensee has ((
)) and (2) the licensee performs ((
)) Therefore, the NRC staff finds that the licensees CGI dedication meets the ASME NQA-1 and 10 CFR Part 50, Appendix B requirements.
3.3.2 Evaluation of Material Qualification and Testing - Watertightness ASME NQA-1 and 10 CFR Part 50, Appendix B require measures to be established for suitability of materials that are essential to the safety-related functions. They also require material qualification to be performed to demonstrate adequacy of performance under design basis conditions. To meet the requirements, the licensee performs the qualification of the CFRP composite ((
)) For qualification testing, the licensee utilizes the industry guidance of AWWA C305-18 and appropriate ASTM standards.
((
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)) The NRC staff finds that the licensees tests are adequate and meet the industry standards.
((
)) The NRC staff finds that these tests are adequate and meet the industry standards.
((
The NRC staff finds that these tests are adequate and meet the industry standards.
((
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)) The NRC staff finds that the CFRP-repaired pipe will have similar layup sequence as the mockup specimens used in the hydrostatic pressure test. The NRC staff determines that the design pressure and temperature of 50 psi and 121 °F, respectively, of the CFRP-repaired pipe are bounded by the laboratory watertightness test conditions. Therefore, the NRC staff finds that the CFRP-repaired pipe is qualified for the watertightness.
((
)) The NRC staffs evaluation of these activities is discussed in section 3.4.
The NRC staff finds that the licensees qualification activities are adequate because the
((
)) will ensure that the mechanical properties of the CFRP materials meet the design criteria and that the structural integrity of the CFRP system is maintained.
3.4 Evaluation of Installation
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The NRC staff evaluation of these activities is as follows.
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)) The NRC staff finds that the licensees surface preparation of the substrate is adequate because it meets the industry standards and provides reasonable assurance that the integrity of the repair will be maintained.
((
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)) Therefore, the NRC staff finds that the CFRP-repaired pipe meets the design requirements.
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3.5 Evaluation of Inspection In addition to the afore-mentioned ((
)) inspection, the licensee stated that it will perform an acceptance examination of the installed CFRP composite system ((
)) Acceptance examinations consist of a visual examination, an acoustic tap test, and a final walkdown. The visual examinations will verify, per the design documents, the absence of ((
)) The acoustic tap testing of the ((
)) The final walkdown will verify that the ((
)) application conforms to the project drawings and foreign material exclusion activities have been completed in accordance with station procedures. The NRC staff finds that the licensees acceptance examination is adequate because these examinations provide reasonable assurance that the CFRP composite system will be free of any unacceptable defects, will be in conformance with the design documents, and all remedial actions applicable for observed defects will be evaluated and documented.
For the preservice inspection prior to startup of the plant and the inservice inspection, the licensee will perform system flow testing in accordance with ASME Code, Section Xl, Subarticle IWA-5244(b)(2) to verify the functionality of the buried CFRP-repaired saltwater pipes and continue to follow its response to NRC Generic Letter 89-13, Service Water System Problems Affecting Safety-Related Equipment (ML031150348), to determine and mitigate the extent of biological fouling, sediment buildup, and corrosion, including microbiologically influenced corrosion. The NRC staff finds that the preservice inspection and inservice inspection of the buried CFRP-repaired saltwater pipes are acceptable because the licensees preservice inspection and inservice inspection follow the requirements of the ASME Code,Section XI.
3.6 Evaluation of Quality Control Program The licensee stated that it will implement a quality assurance and quality oversight program that involve a quality assurance plan, ((