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NET-300047-07 Revision 1, Material Qualification Report of Maxus for Spent Fuel Storage.
	ML15336A084
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Site:	Palo Verde
Issue date:	11/30/2015
From:	Rickard B; Curtiss-Wright Corp, NETCO Products & Services
To:	; Office of Nuclear Reactor Regulation
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	102-07149-MLL/TNW, CAW-15-4271 NET-300047-07 Rev. 1
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Enclosure Description and Assessment of Proposed License Amendment ATTACHMENT 6 Material QualificationReport of MAXUS for Spent Fuel Storage, NET-300047-07 Rev 1, November 2015

Nuclear Division CURTISS WRIGHT-NETCO 44 Shelter Rock Rd., Danbury, CT 06810 T: 203.448.3310 I F: 203.437.6279 http://scientech.cwfc.com NET-300047-07 Rev. 1 I EGD NO.: 28079-003, Rev. 1 Material Qualification Report of MAXUS for Spent Fuel Storage Prepared by:

NETCO Business Segment Scientech, Nuclear Division 44 Shelter Rock [

Danbury, CT 06811 Rev: Date: J Prepared by: JReviewed by: IApproved by:]

0 10/12/2015 Brian Rickard S. Leuenroth C. Ilioiu Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I TABLE OF CONTENTS LIST OF FIGURES ...................................................................................... II LIST OF TABLES........................................................................................ III

1.0 INTRODUCTION

AND

SUMMARY

............................................................... I

2.0 DESCRIPTION

OF THE NETCO-SNAP-IN AND INSTALLATION TOOLING.............. 3 2.1 NETCO-SNAP-IN INSERT...................................................................... 3 2.2 SYSTEM ANCILLARY EQUIPMENT................................................................... 4 3.0 MANUFACTURING THE NETCO-SNAP-IN NEUTRON ABSORBER INSERT............ 8 3.1 PRODUCTION OF MAXUS....................................................................... 8 3.2 NETCO-SNAP-IN PRODUCTION ................................................................. 8 3.3 QUALITY ASSURANCE............................................................................. 8 4.0 ENGINEERING EVALUATION OF THE MAXUS COMPOSITE ............................ 11 4.1 COMPARISON OF MAXUSWITH BORALTM ................................................... 11 4.2 IN-SERVICE PERFORMANCE OF ALUMINUM MATRIX NEUTRON ABSORBER MATERIAL......... 15 4.3 NETCO EXPERIENCE & CAPABILITIES ............................................................ 22 5.0 ACCELERATED CORROSION TESTING...................................................... 24 5.1 TEST DESCRIPTION ................................................................................ 24 5.2 WATER CHEMISTRY ................................................................................ 24 5.3 TEST MATRICES AND COUPON DESCRIPTIONS ................................................... 32 5.4 CORROSION TEST RESULTS ....................................................................... 33 5.5 DISCUSSION OF ACCELERATED CORROSION RESULTS .......................................... 36 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I List of Figures 2-1 NE=TCO-SNAP-IN............................................................................. 3 2-2 Installed NE=TCO-S NAP-IN .................................................................. 4 2-3 NETCO-SNAP-IN Insert Installation Tool with Insert Loaded.............................. 6 2-4 NETCO-SNAP-IN Insert Removal Tool ..................................................... 7 4-1 Comparison of Manufacturing Processes................................................... 13 4-2 Micro Photograph of BORALTM .............................................................. 14 5-1 Displays the pH of the BWR and PWR baths over the length of the test ................. 25 5-2 Displays the conductivity of the BWR and PWR baths over the length of the test ............................................................. 26 5-3 Displays the chloride concentration of the BWR and PWR baths over the length of the test ............................................................. 27 5-4 Displays the fluoride concentration of the BWR and PWR baths over the length of the test ............................................................. 28 5-5 Displays the aluminum concentration of the BWR and PWR baths over the length of the test............................................................. 29 5-6 Displays the sulfate concentration of the BWR and PWR baths over the length of the test ............................................................. 30 5-7 Displays the boron concentration of the PWR bath over the length of the test....................... ................................................... 31 ii Curtiss-Wright \ Nuclear Division \ NETCO

rM~r 'l" AfrlA7 /'A7 D-..., ,I EGD NO.: 28079-003, Rev. 1 I'LsU tV, [r, Iv List of Tables 3-1 Insert Quaiity Assurance Testing Summary.................................................. 9 4-1 Comparison of Aluminum Alloy Matrices .................. ;................................. 11 4-2 Comparison of Boron Carbide............................................................... 12 4-3 Partial Listing of Research and Test Reactors Where BORALTM Has Been Used............................................................................... 16 4-4 Partial List of LWRs Where BORALTM Has Been Used in Spent Fuel Storage Racks ................................................................... 16 4-5 Partial List of LWRs Where BORALTM Has Been Used in Dry Storage Casks ........................................................................... 20 5-1 Shows the tally for each coupon type....................................................... 32 5-2 Displays required pre- and post-characterization for all test coupons .................... 33 5-3 Displays boron-i10 areal density measurements for the one year test coupons /cm2 ] .....................................................................

lo[g-8B 34 5-4 Displays boron-i10 areal density measurements for the two year test coupons [g-B1 °/cm2 ]....................................................................... 34 5-5 Displays equivalent corrosion rates for 80°F and 120°F pools............................ 35 III Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 1.0 Introduction and Summary The purpose of this report is to demonstrate that aluminum-boron carbide sheet called MAXUS, supplied by Nikkeikin Aluminum Core Technology Co., Ltd., is a suitable material for use as a neutron absorber in spent nuclear fuel storage applications, and that in particular, it is a suitable material from which to fabricate NETCO-SNAP-IN neutron absorber inserts. The NETCO-SNAP-IN neutron absorber insert is installed in existing spent fuel storage racks to restore or supplement the reactivity hold-down capability of spent fuel pool racks. Once installed, these neutron absorber inserts become permanently affixed to the storage racks.

The suitability of the MAXUS material as demonstrated herein is based upon:

Detailed comparison with highly similar material with a successful record of industry-wide, in-service performance

Accelerated corrosion testing in simulated BWR and PWR spent fuel pool environments

Evaluating and testing of mechanical properties to verify acceptability of installed insert retention force

Measurement of B10 areal density to confirm satisfactory neutron absorption capability

Long term in-situ coupon surveillance programs.

These evaluations are detailed in the various sections of this report.

MAXUS material is a tightly bound laminated metal matrix composite that is produced using powder metallurgy techniques. This material consists of a 5000 series aluminum alloy outer clad tightly bound to an inner core of 1000 series aluminum reinforced with boron carbide. The boron carbide content varies by weight percent depending on the specified areal density requirements.

As stated above, one particular application of the MAXUS composite in spent fuel pools is the NETCO-SNAP-IN neutron absorber insert. The NETCO-SNAP-IN is proprietary to NETCO and is protected by U.S. Patent No. 6,741,669 B2 [1-. The NETCO-SNAP-IN inserts have been installed and licensed at Exelon's LaSalle, Peach Bottom, and Quad Cities nuclear plants, all of which are BWR plants. The first use of NETCO-SNAP-IN absorber inserts in a PWR spent fuel pool will be at Arizona Public Service Co.'s Palo Verde Station, Units 1, 2, and 3.

Guidance has been published for the qualification and acceptance of new boron based metallic neutron absorbers for storage and transportation casks. [1-2] Using this 1

Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 document as a guide, the qualification process described in this report consists of the following elements:

Review of the composition and manufacturing process of the MAXUS composite and a detailed comparison with the composition and manufacturing process for BORALTM, a neutron absorber material that has been successfully used extensively worldwide for spent nuclear fuel storage racks for the last 40 years.

An accelerated corrosion program has been completed in both demineralized water and boric acid (2500 ppm as boron). The program ran for two years in duration. Interim and final results are reported.

A long term surveillance assembly will be placed in the Palo Verde pools prior to the installation of the first NETCO-SNAP-IN inserts. The assembly will hold the following types of coupons o MAXUS composite coupons o MAXUS composite coupons coupled with 304 stainless steel, Inconel 718, and Zircaloy samples o MAXUS composite bend coupons The following sections of this report describe:

- NETCO-SNAP-IN and Installation Tooling

- Manufacturing process and quality control used for NETCO-SNAP-IN inserts

- Composition and physical properties of the MAXUS composite

- Description of accelerated corrosion testing and interim results

- Comparative evaluation of MAXUS composite and BORAL TM

-Anticipated performance of MAXUS in spent fuel pools References Section 1 1-1. Lindquist, K. 0., U.S. Patent No. 6,741,669 B2, "Neutron Absorber Systems and Method for Absorbing Neutrons," May 25, 2004.

1-2. ASTM C 1671-07, "Standard Practice for Qualification and Acceptance of Boron Based Metallic Neutron Absorbers for Nuclear Criticality Control for Dry Cask Storage Systems and Transportation Packaging."

2 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I 2.0 Description of the NETCO-SNAP-IN and Installation Tooling The NETCO-SNAP-IN system is composed of the spent fuel storage rack inserts (NETCO- SNAP-IN) and the system ancillary equipment. The ancillary equipment consists of the insert installation tool, insert removal tool, and surveillance sample coupon system.

2.1 NETCO-SNAP-IN Insert The NETCO-SNAP-IN insert increases the reactivity suppression of the spent fuel racks by installing a thin, chevron-shaped metallic insert into the fuel storage cell of the rack. The insert is fabricated from a single sheet of an aluminum-boron carbide metal matrix composite. When installed, the insert abuts two adjacent faces of the rack wall.

Since the inserts are fabricated from a neutron absorbing material, additional reactivity suppression is achieved once the inserts are in place.

Figure 2-1 illustrates a typical NETCO-SNAP-IN insert. The insert has a length equivalent to the length of the fuel storage cell and the lower end is tapered to facilitate installation. The chevron is formed with a central bend angle along its length. The width of each wing of the chevron is slightly less than the minimum inside dimension of the fuel storage cell. Near the top of the NETCO-SNAP-IN insert is a circular hole in each wing that engages the installation tool. The rectangular holes in each insert wing allow engagement of the removal tool.

Figure 2-1: NETCO-SNAP-IN 3

Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 The chevrons are formed with a greater than 9Q0 bend angle which causes compression of the insert as it is pushed into the rack cell and assumes the 9Q0 angle between adjacent rack cell walls. The insert is designed to become an integral part of the fuel rack once it has been installed. This is achieved through the elastic deformation of the insert bearing against the rack cell wall and the associated friction force. The force exerted due to this deformation is predicted by the effective spring constant of the insert. The force between the insert wings and the rack cell walls in conjunction with the static friction between these surfaces serves to retain the NETCQ-SNAP-IN insert and make it an integral part of the rack upon installation. The photo below in Figure 2-2 illustrates the fit of the NETCO-SNAP-IN insert within an actual spent fuel storage rack cell.

Spent Fuel Rack Cell NETCO-SNAP-IN IInsert I

Figure 2-2: Installed NETCO-S NAP-IN 2.2 System Ancillary Equipment The ancillary equipment associated with the NETCO-SNAP-IN insert system supports the installation and removal of the inserts and placement of fuel into spent fuel storage rack cells.

The material surveillance coupons and in-rack coupon holders provide a means to monitor the corrosion and material performance of the inserts without the need to remove and destructively exam an installed insert.

4 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 2.2.1 NETCO-SNAP-IN Insert Installation Tool The installation tool is the primary element of the ancillary equipment set that will be used during NETCO-SNAP-IN insert installation. At the top of the installation tool is a hoist attachment point. The configuration of the hoist attachment point, also known as the bail, is such that a station auxiliary grapple can engage to the installation tool. The bail (or other connecting hardware) on the install tool is attached to an anvil assembly that provides a bearing surface for the top edge of the insert. Immediately below the anvil assembly is the head assembly. The head assembly contains two spring loaded cylinders, which engage the insert while it is being moved to the storage cell into which it is destined for installation. During installation, when the cylinders come into contact with the rack cell wall, they retract, thus allowing full insertion of the NETCO-SNAP- IN insert. The curvature of the upper edge of each cylinder is so configured that when the insert is fully installed upward movement of the tool allows the cylinder to clear the engagement holes in the insert, leaving the insert fully seated in the rack cell. A counterweight is suspended below the head assembly. In addition to partially providing downward insertion force, the counterweight contributes to insert stability during installation by lowering the center of gravity of the tool. The insertion tool is constructed entirely of stainless steel and, fully loaded, will weigh less than 1500 lbs. which should conform with station load limit requirements regarding suspension of loads over fuel.

The elements of the installation tool described above are illustrated in Figure 2-3.

5 Curtiss-Wright \ Nuclear Division \ NETCQ

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Figure 2-3: NE TCO-S NA P-IN INSERT INSTALLA TION TOOL WITH INSERT LOADED 2.2.2 NETCO-SNAP-IN Insert Removal Tool The removal tool is provided as a maintenance tool to support removal of the inserts from the installed location. In the event that an insert requires replacement, or if an insert is required to be removed for examination as part of the insert performance surveillance program, the removal tool provides a convenient method for engaging and removing an insert from a storage cell. At the top of the removal tool is a hoist attachment point. The configuration of the hoist attachment point, also known as the bail, is such that a station auxiliary grapple can engage to removal tool in essentially the same manner as the installation tool. The bail is attached to the 6

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EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 SNAP-IN engagement head assembly that latches into the rectangular holes in the upper part of the insert. The head assembly contains two spring loaded blocks, which engage the insert while it is in the storage cell. When the tool is seated, the latching hooks engage the SNAP-IN allowing the insert to be removed. The removal tool is constructed entirely of stainless steel and fully loaded will weigh less than 100 lbs. The illustration in Figure 2-4 shows the described elements of the insert removal tool.

uFmN SA.

Figure 2-4: NETCO-SNAP.IN INSERT REMOVAL TOOL 7

Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 3.0 Manufacturing the NETCO-SNAP-IN Neutron Absorber Insert 3.1 Borated Aluminum Sheet Production MAXUS is a Metal Matrix Composite (MMC) neutron absorber that is manufactured entirely in-house by Nikkeikin Aluminum Core Technology Co., Ltd. First, 5000 series aluminum ingot is rolled and pressed into a case shape. Afterwards, Al 070 is atomized into aluminum powder and then uniformly mixedl with a precise amount of B 4 C powder.

The aluminum case is then filled with the uniform matrix of aluminum and B4 C powder.

After the filling process is complete, the case is welded to an aluminum frame on its four sides.

The welded case is heated first and then rolled into a sheet. The sheet, which has been rolled to final thickness, is annealed and then it is leveled. The final MMC sheet is trimmed to dimensions by precision water jet cutting. During this time, the aluminum frame previously welded around the case is cut off.

3.2 NETCO-SNAP-IN Production Once the MAXUS MMC sheet has been produced, the shaped insert, alqng with the holes that engage the installation and removal tools, are extracted from tlbe sheet by water jet cutting. The extracted insert sheet is formed on a press brake to an angle greater than 900 to achieve the final insert.

3.3 Quality Assurance The NETCO-SNAP-INs are designed and fabricated under control and surveillance of NETCO's Quality Assurance Program [3-1] that conforms to the requirements of 10CFR50 Appendix B. Since the NETCO-SNAP-IN inserts are used for reactivity control of fuel assemblies stored in close proximity, they are classified as nuclear Safety Related (SR). As such, and as required by NETCO's 10CFR50 Appendix B Quality Assurance Program1 3 -1], they are designed and fabricated to preclude the use of any material or manufacturing process that deviates from a rigorous set of specifications established by the NETCO design team. Process controls for materials and fabrication are established to preclude the incidence of errors and inspection steps are implemented to ensure that all critical attributes, as identified by the design team, for the feed material, rolled sheet, and bending and forming are satisfactorily achieved in the final product.

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EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 The raw materials, including the 5000 series aluminum, 1000 series aluminum, and B4 C used to make the rolled sheets, are secured by Nikkeikin Aluminum Core Technology (ACT) from approved qualified suppliers. The material certifications supplied with the feed material are subject to independent verification and testing upon receipt of materials to confirm product acceptability. An independent mass spectroscopic measurement of boron-l0 fraction is performed on each lot of boron carbide powder used. Each blended batch of 840 and aluminum powder is chemically analyzed to ensure that the composition conforms to the design specification for weight fraction of boron and Al. Permanent records of these analyses are retained in NETCO's quality assurance files. Each completed NETCO-SNAP-IN has a unique identifying number etched along the inside upper surface traceable to the sheet and feed material lots.

Additionally, for the purpose of confirming final product neutronic hold down capabilities, traceable coupons are extracted from each rolled insert blank, which yields one NETCO-SNAP-IN insert. The sample coupons from the sheets are subjected to 100%

neutron attenuation testing to verify as-manufactured boron-l0 areal density and 100%

mechanical testing to verify tensile properties.

Quality Assurance procedures and process controls are enforced on the fabrication shop floor, which provides reasonable assurance that the final product will comply with all quality assurance requirelments. The final product is subject to one hundred percent final inspection at the man ufacturing supplier facility. The final inspection verification includes verification of insert dimensions, formed angle, bend, twist, cleanliness, identifying markings and freedom from imperfections.

A summary of the insert associated critical characteristics and qualification tests performed in support of those characteristics is shown in Table 3-1.

Table 3-1 Insert Quality Assurance Testing Summary Critical Characteristic Qualification Testing Objective Performed Minimum B-10 Areal Neutron Attenuation Verify that Areal Density Density Testing exceeds the minimum certified value Material Composition lCP Analysis Verify that Boron, Carbon, and Aluminum are within specification limits 9

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EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 Mechanical Properties Tensile Testing Verify mechanical properties are within acceptable limits to support mechanical design specifications.

References Section 3 3-1. Quality Assurance Manual, Rev. 2, NETCO, a business unit of Curtiss-Wright Flow Control Company, 2011.

10 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 4.0 Engineering Evaluation of the MAXUS Composite The MAXUS composite is similar in composition to another neutron absorber material, BORALTM, which has been used extensively for more than 40 years for both wet and dry storage applications. The in-service performance of BORALTM has been good. In this section the composition, physical properties and mechanical properties of both materials are compared and the industry experience with the BORALTM neutron absorber reviewed.

4.1 Comparison of MAXUS with BORAL TM 4.1.1 Composition Both of these neutron absorber materials utilize close to pure aluminum as the base alloy for the metal matrix that retains the boron carbide. The compositions of the alloy matrices are compared in Table 4-1. With the exception of the addition of Mg and Cr for the MAXUS clad material, as noted previously, the compositions are similar. In fact, the MAXUS requirement for other elements is somewhat more stringent than the BORAL TM requirement. Specifically, the higher purity aluminum in the MAXUS core significantly decreases porosity and increases bonding with the clad material. This reduces any possibility of blistering i'n the MAXUS composite.

Table 4-1: Comparison of Aluminum Alloy Matrices MAXUS AA1100 BORAL MAXUS Cmoie2 Property UNS A91 100 Metal Matrix AA5052 Alloy Metal Matrix wt% Core B4C Material Core Material Typical Temper O Spec Spec Properties (including clad)

Al 99.00% min 99.00% min 95.75% min 99.70% min 82.0%

Si & Fe 0.95% max 1.00% max 0.40% max 0.25% max 0.59%

Cu 0.05-0.20% 0.05-0.20% 0.10% max 0.04% max 0.10% max Mn 0.05% max 0.05% max 0.10% max 0.03% max 0.10% max 11 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Zn 0.10% max 0.10% max 0.10% max 0.04% max 0.10% max Mg 2.2% - 2.8% 0.03% max 0.10% max Cr 0.15%~0.35% 0.10% max Ti 0.03% max 0.10% max B4C 15.2% -18.9%

Ohr 0.15% total 0.15% total Ohr0.15% max 0.03% max 0.10% max 0.05% max each 0.05% max each each Elements eahac The boron carbide specifications are compared in Table 4-2. The MAXUS specification is somewhat tighter in terms of allowable impurities and requires a much smaller particle size. With respect to the latter, the smaller particle size results in a more homogeneous absorber, less potential for neutron streaming and a more effective neutron absorber material.

Table 4-2: Comparison of Boron Carbide BORAL TM Constituent MAXUS Composite 70.0 min Total Boron 75 wt% min 3.0 max Boric Oxide 0.5 % max 2.0 max Iron 1.0% max 94.0 min Total Boron & Carbon 95% min 75 - 250 p~m Particle Size 1-0p pm) D0 93 4.1.2 Manufacturing Process Physical Form The manufacturing processes for BORALTM and the MAXUS composite are compared in Figure 4-1. The manufacture of BORAL TM starts with the complete blending of 12 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NL -~3UUU47-U7 Rev 1 atomized AA1100 powder and boron carbide. An AA1100 rectangular box ~12 to 15 inches on a side and a few inches high depending on the thickness of the finished product is filled with the blended powder. The walls of the box are ~ 1 inch thick. After a top is welded on the box, the billet is ready for hot rolling to final gage.

The production process for the MAXUS material is very similar and differs mainly in the purity of the aluminum mixed with the boron carbide in the core and the box material.

BORALTM Blend Fill AA1 100 Hot Roll Powdered =i Box + =i Billet to Al + B4C Weld Lid Final Gage MAXUS COMPOSITE Blend Fill AA5052 Hot Roll Powdered High Purity *. Box + Filled Case to Al + B4C Weld Lid Final Gage Figure 4-1: Comparison of Manufacturing Processes In its finished form, BORAL TM consists of 1) a core of uniformly mixed and distributed boron carbide and alloy AA1100 aluminum particles; and 2) an AA1100 surface cladding on both sides of the core, serving as a solid barrier. Figure 4-2 is a micro photograph of the edge of a BORAL TM sample showing the core and clad region.

BORALTM has been produced with the core containing anywhere between 35 w% and 65 w% boron carbide. For most cores produced recently, the core contains about 50 w% boron carbide. In addition, the core is not fully dense and contains as much as 5%

open and interconnected porosity.

The MAXUS composite, on the other hand, in its final form has an almost fully dense core due to the purity of the aluminum used in the powder. As such it contains a negligible amount of porosity that could allow water intrusion and potential problems associated with internal moisture.

13 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 Figure 4-2: Micro Photograph of BORAL 4.1.3 Stress Relaxation During installation, the absorber inserts are compressed from an initial bend angle greater than 90° to the square dimensions of the rack cell interior. Once installed, the inserts maintain a fixed strain within the rack storage cell that may be susceptible to relaxation over time. An analysis of stress relaxation in aluminum alloys has been performed to establish the expected performance of the inserts in this regard.

Due to the inclusion of boron carbide and a 5052 series cladding, it is estimated that the MAXUS material will have similar mechanical characteristics to 6061 aluminum alloy material. Reference 4-1 details stress relaxation performance of 6061 -T6 alloy after 1000 hours0.0116 days 0.278 hours 0.00165 weeks 3.805e-4 months at various temperatures. The data shows approximately 15% stress relaxation after 1000 hours0.0116 days 0.278 hours 0.00165 weeks 3.805e-4 months at 1000 C.[4 1-Yearly averaged bulk pool temperatures within spent fuel pools can be approximately 850 F. Stress relaxation at this temperature is expected to be significantly lower than 15% over 1000 hours0.0116 days 0.278 hours 0.00165 weeks 3.805e-4 months . As an upper limit, however, data for AA1100-H112 series 14 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I aluminum 14-2] was analyzed to estimate total stress relaxation after 20 years of service.

The results of that analysis showed that the AAI 100 series aluminum was, based upon extrapolated data, expected to have experienced an approximate stress reduction of 50% over 20 years. More recent analytical models have put the stress relaxation at 60%

over the same time period. Given the reduction in elongation of the MAXUS composite in comparison with AAI 100 series aluminum, this stress relaxation is likely an upper limit for the performance of the MAXUS material.

While stress relaxation estimates are based on performance of AAI1100 series material in the worst case, the following factors would tend to mitigate the stress relaxation effects of the MAXUS material:

1. Stress relaxation in boron carbide reinforced aluminum will be less than for the pure alloy;

2. The presence of the 5052 series cladding will reduce the overall stress relaxation of the composite since 5052 has stress relaxation properties similar to 6061 aluminum.

4.2 In-Service Performance of Aluminum Matrix Neutron Absorber Material BORAL TM has been used for nuclear applications for almost 45 years starting in 1964 when it was used for reactivity control in the Yankee Rowe spent fuel racks. Nuclear applications include control elements for test reactors, fuel storage racks for spent nuclear fuel and in dry fuel storage and transportation casks. Table 4-3 contains a partial listing of research reactors where BORALTM has been used. Table 4-4 contains a partial list of LWR plants where BORAL TM has been used in spent fuel storage racks.

Table 4-5 is a partial list of plants where BORAL TM has been used for reactivity control in dry storage casks.

For dry storage applications, it is noted that the Alcan composite is now approved for use in the NUHOMS dry storage system as well as the Transnuclear metal cask storage system. The Alcan composite is being used at Peach Bottom, Limerick and St. Lucie as well as in Europe.

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NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Table 4-3: Partial Listing of Research and Test Reactors Where B ORAL *'Has Been Used Research and Test Reactors AE-6 (USAEC)

BORAX-5 (USAEC)

Brookhaven Medical Research Reactor JEN-l (Spain)

Philippine Research-i Rhode Island Reactor Triga Mark II (Italy, Austria, etc.)

University of Kansas Reactor University of Wisconsin Reactor Venezuela-I Washington State University Reactor IL Table 4-4:

Partial List of LWRs Where BORAL *Has Been Used in Spent Fuel Storage Racks Pool Plant Type Manufacturer iSoctionsge Strg Country BEAVER VALLEY 1 PWR Holtec 1621 USA BELLEFONTE 1 PWR Westinghouse 1058 USA BRAIDWOOD 1&2 PWR Holtec 2984 USA BROWNS FERRY 1 BWR GE 3471 USA BROWNS FERRY 2 BWR GE 3471 USA BROWNS FERRY 3 BWR GE 3471 USA BRUNSWICK I BWR Holtec 1839 USA BYRON 1&2 PWR Holtec 2984 USA CALLAWAY PWR Holtec 1302 USA 16 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 Pool COMANCHE PEAK 1 Plant Type PWR Manufacturer Holtec

]Locations Storage 222 Conr Conr USA COMANCHE PEAK 2 PWR Holtec 219 USA CONN YANKEE PWR Holtec USA COOK 1&2 PWR Holtec 3613 USA COOPER BWR NES USA CRYSTAL RIVER 3 PWR Westinghouse 932 USA DAVIS BESSE 1 PWR Holtec 1624 USA DRESDEN I BWR CECO 3537 USA DRESDEN 2 BWR CECO 3537 USA DRESDEN 3 BWR CECO 3537 USA DUANE ARNOLD BWR PAR 1898 USA DUANE ARNOLD :BWR Holtec 1254 USA FERMI 2 BWR Holtec 559 USA FITZPATRICK BWR PAR 2797 USA FITZPATRICK BWR Holtec USA FT. CALHOUN PWR Holtec 160 USA HARRIS I PWR Holtec 484 USA HATCH 1 BWR GE 5830 USA HATCH 2 BWR GE 2765 USA HOPE CREEK BWR Holtec 3998 USA HUMBOLDT BAY 3 BWR Unknown USA INDIAN POINT 3 PWR UST&D 1340 USA KEWAUNEE PWR Holtec 215 USA KOEBERG 1 PWR Holtec South Africa KOEBERG 2 PWR Holtec South Africa 17 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Pool [Plant Type Manufacturer StCountr KORI-4 PWR Holtec South Korea KUOSHENG 1 BWR ENSA 1578 Taiwan KUOSHENG 2 BWR ENSA 1578 Taiwan

'LAGUNA VERDE 1 BWR Holtec Mexico LAGUNA VERDE 2 BWR Holtec Mexico LASALLE 1 BWR UST&D 14029 !USA LIMERICK 1 IBWR Holtec 2500 USA LIMERICK 2 BWR Holtec 2766 USA MAINE YANKEE PWR PAR 1464 USA MCGUIRE 1 PWR Holtec 286 USA MCGUIRE 2 PWR Holtec 286 USA MILLSTONE 3 PWR Holtec 1104 USA MONTICELLO BWR GE 2229 USA NINE MILE POINT 1 BWR Holtec 3496 USA OYSTER CREEK BWR Holtec 390 USA PERRY 1 BWR PAR 2400 USA PERRY 2 BWR PAR 1620 USA PILGRIM BWR Holtec 1539 USA SALEM 1 PWR ENC 1117 USA SALEM 1 PWR Holtec 1117 USA SALEM 2 PWR ENC. 1139 USA SALEM 2 PWR Holtec 1139 USA SEABROOK 1 PWR Westinghouse 576 USA SEQUOYAH 1 PWR Westinghouse 2091 USA SEQUOYAH 2 PWR Holtec USA 18 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Pool Plant Type Manufacturer Storage Locations~ Conr SEQUOYAH 2 PWR PAR 2091 USA SIZEWELL B PWR Holtec 1901 United Kingdom SUMMER 1 PWR Holtec 1712 USA SUSQUEHANNA 1 BWR PAR 2840 USA SUSQUEHANNA 2 BWR PAR 2840 USA THREE MILE ISLAND 1 PWR Holtec 1284 USA TURKEY POINT 3 PWR Holtec 131 USA TURKEY POINT 4 PWR Holtec 131 'USA ULCHIN 1 PWR Holtec 1000 South Korea VERMONT YANKEE BWR UST&D 2860 USA VOGTLE 1 PWR Unknown 1476 USA WATERFORD 3 PWR Holtec 2232 USA WATTS BAR 1 PWR Holtec 1610 USA WATTS BAR 2 PWR Holtec 1610 USA YANKEE ROWE PWR PAR 721 USA YONGGWANG 1 PWR Holtec 1152 South Korea YONGGWANG 2 PWR Holtec 1152 South Korea ZION 1 PWR Holtec 3012 USA ZION 2 PWR Holtec 3012 USA ANGRA 1 PWR Holtec 1252 Brazil CATTENOM-1 PWR Framatome 2520 France CATTENOM-2 PWR Framatome 2520 =France CATTENOM-3 PWR Framatome 2520 France CATTENOM-4 PWR Framatome 2520 France BELLEVILLE-1 PWR Framatome 1260 France 19 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Poo t lan Tye PoolPlan Typ IManfacure IStorage ManfactrerLocations Country BELLEVILLE-2 PWR Framatome 1260 France NOGENT-1 PWR Framatome 1260 France NOGENT-2 PWR Framatome 1260 France PENLY-1 PWR Framatome 1260 France PENLY-2 PWR Framatome 1260 France GOLFECH-1 PWR Framatome 1260 France GOLFECH-2 PWR Framatome 1260 France Table 4-5: Partial Listing of LWRs Where BORAL *Has Been Used in Dry Storage Casks Plant ICurrent Type Supplier Inventory Module Capacity Absorber Type ARKANSAS 2 Hi-Storm 100(MPC-32) Holtec 416 32 BORAL CATAWBA 1 UMS-24 NAC 24 BORAL DIABLO CANYON 1 Hi-Storm 100(MPC-32) Holtec BORAL DIABLO CANYON 2 Hi-Storm 100(MPC-24) Holtec BORAL DRESDEN 2 Hi-Storm 100(MPC-68) Holtec 1632 68 BORAL DUANE ARNOLD NUHOMS-61BT Transnuclear 610 61 BORAL FITZPATRICK ;Hi-Storm 100(MPC-68) Holtec 204 68 BORAL HADDAM NECK MPC-24 NAC 651 24 BORAL HATCH 2 Hi-Storm 100(MPC-68) Holtec 1496 68 BORAL

'MAINE YANKEE UMS-24 NAC 1440 24 BORAL PALO VERDE 1 UMS-24 NAC 624 24 BORAL PEACH BOTTOM 2 TN-68 Transnuclear 1632 68 BORAL PRAIRIE ISLAND I TN-40 Transnuclear 680 40 BORAL SEQUOYAH 2 Hi-Storm 100(MPC-32) Holtec 96 32 BORAL TROJAN MPC(24)-Only Holtec 816 24 BORAL 20 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1

~SUSQUEHANNA 1 'NUHOMS-61BT Transnuclear 183 61 BORAL

as of mid-2005 In-Service Experience 4.2.1 BORAL TM Plate and Sheet in Wet Storage It has been noted that in conventional storage racks, once BORALTM is installed in fuel racks, it is not accessible for inspection to determine its in-service performance.

Accordingly, the NRC has, in the past, required utilities to initiate a coupon surveillance program when new racks were installed. A coupon surveillance program consists of a series of small coupons either in a shroud (simulating the manner in which the BORALTM is encapsulated) or bare. The coupons are generally attached to a surveillance assembly, which is placed in a spent fuel rack storage cell.

The surveillance assembly is generally surrounded by recently discharged fuel assemblies to accelerate the rate at which the coupons accumulate gamma exposure.

Prior to placing the assembly in service, the b~oupons are generally characterized with respect to:

visual appearance

dry weight

dimensions

specific gravity and density

boron-i10 areal density Periodically, coupons are removed from the surveillance assembly and sent to an independent laboratory for testing. The post-irradiation test results generally mirror the pre-irradiation test results. As the surveillance coupons are prepared from BORALTM coupons cut from panels taken from the same production lot(s) used in the racks, the performance of the coupons should be indicative of the performance of the material in the racks.

NETCO maintains laboratory facilities and offers inspection and testing services of neutron absorber surveillance coupons. In that capacity, NETCO has inspected hundreds of aluminum matrix surveillance coupons, many of them BORALTM, from spent fuel pools around the world. It has been observed during testing that some surveillance coupons can be subject to a generalized corrosion that includes the development of a uniform oxide film. This film, once it forms, tends to be self-passivating and prevents 21 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 further corrosion. Depending on pooi conditions, other coupons can be susceptible to localized pitting corrosion. It should be noted that while these corrosion effects can occur in aluminum matrix neutron absorbers, to date this in-service corrosion has not resulted in any detectable decrease in the boron-l0 areal density. It is therefore concluded that the aluminum alloy matrix serves as suitable matrix to retain the boron carbide in spent fuel storage racks. Additional qualification testing has been performed to further demonstrate the corrosion resistance of the MAXUS material in BWR and PWR spent fuel pool applications. This testing is described in Section 5.0 of this report.

4.3 NETCO Experience & Capabilities Through its extensive involvement in providing a broad spectrum of engineering services to the nuclear power industry, Scientech has developed the technical capabilities and experience essential to the successful accomplishment of the proposed program. In addition to diversified experience in supporting nuclear utilities in the areas of fuel handling and inspection equipment, stress and seismic analysis, nuclear engineering and plant licensing assistance, Scientech has specific experience in the design, analysis, licensing and fabrication of neutron absorber inserts for spent fuel storage racks.

NETCO, a segment of Scientech's Engineered Products Division, is a market leader in providing Spent Fuel Management services.

Established in 1982 by Dr. Kenneth Lindquist, NETCO provides product and service solutions that address the performance of neutron absorbing materials in spent fuel storage racks; in addition to numerous analytical services related to nuclear fuel storage.

BADGER Testing-- BADGER is a fully computerized, in-situ scanning system that measures the efficacy of neutron absorbing materials like Boraflex. It offers the only quantitative technique for assaying spent fuel racks. Many utilities have committed to the NRC to perform periodic BADGER testing to verify the adequacy of neutron absorber materials and to confirm RACKLIFE calculations.

Analytical Services- NETCO is a leader in the design analysis of spent fuel racks and dry storage casks by providing criticality, thermal and shielding analysis. They have a family of software products used to determine the performance of the neutron absorbers in spent fuel pools and aid utilities in loading spent fuel storage casks.

Laboratory Testing-NETCO is the industry leader in the qualification, acceptance and surveillance testing of neutron absorber materials. This can be performed on any remaining surveillance material coupons. Services include neutron attenuation, 22 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 accelerated corrosion, elevated temperature and accelerated radiation testing. Neutron attenuation testing is performed to determine boron-10 areal density of the absorber material.

NETCO Snap-In-- SNAP-IN is a patented neutron absorbing product which extends the useful life of fuel storage racks. Snap-In inserts are installed in fuel storage cells using simple tooling which is operated above the pool from the spent fuel pool bridge.

References for Section 4.0 4-I K. Farrell, "ORNL/TM-13049 Assessment of Aluminum Structural Materials for Service Within the ANS Reflector Vessel," Oak Ridge National Laboratory, August 1995 4-2 John Gilbert Kaufman, Properties of Aluminum Alloys, ASM International, 1999 23 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I 5.0 Accelerated Corrosion Testing 5.1 Test Description The accelerated corrosion test program has been created to determine the corrosion characteristics of MAXUS aluminum composite material in BWR and PWR spent fuel pools over an extended service life. Two sets of test coupons are currently being tested in the NETCO laboratory. One set is placed in a demineralized water bath to simulate conditions in a BWR pool, while the other set is placed in a demineralized water bath containing boric acid to simulate conditions in a PWR pool. The normal operating temperature of spent fuel pools ranges from 80°F to 100°F. The water baths in the NETCO lab are set to 1950 F to accelerate the corrosion of the MAXUS materials.

These water baths and conditions are also used to perform the testing as proposed in ML12283A046.[ 8 ] Coupons are pulled at 4000hr (half a year), one year, two years, three years, four years, and five years. This interim report highlights the results from the two year coupons, pulled on 1/14/2015. Coupons are measured for weights, density, dimensional measurements, and neutron attenuation before placed in the water baths.

The couPons are again put through the same measurements after removing them from the baths. This data is used to determine a corrosion rate for the MAXUS material.

5.2 Water Chemistry The water baths were created to most similarly represent the conditions of a nuclear power plant's spent fuel pool. Requirements were established that closely mimicked requirements put forth by fuel fabricators for interim wet storage. These requirements drive the chemistry testing scope of pH, conductivity, the fluoride ion, the chloride ion, the aluminum ion, the sulfate ion, and boron content (PWR only). The pH and conductivity tests are performed weekly, while the other tests are performed monthly (boron tested when performing feed and bleeds). These requirements are held by performing a feed and bleed process if any criterion fails the requirement.

The water used in both baths is tap water filtered by a distiller. The BWR bath was filled in a similar manner to the PWR bath with the exception that the PWR bath contains 2500ppm +/- l00ppm boron, as boric acid. All pH and conductivity readings were taken at ~~20°C by NETCO qualified personnel. All ion concentration measurements are performed by a NETCO qualified external laboratory. The following Figures 5-1 through Figure 5-7 show the results for all test measurement.

24 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 pH 9.00 8.50 8.00 7.50 7.00 1.6.50

-- BWR 6.00

1-' PWR 5.50 5.00 4.50 4.00 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Elapsed Testing Hours Figure 5-1: Displays the pH of the BWR and PWR baths over the length of the test 25 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 Conductivity 18.00 16.00 14.00 12.00 10.00 S8.00 -.4- BWR

,., PWR 6.00 4.00 2.00 0.00 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Elapsed Testing Hours Figure 5-2: Displays the conductivity of the BWR and PWR baths over the length of the test 26 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Chloride Concentration 0.25 0.2 0.15 E

a.

'-4-'-BW R

-U--PW R 0.1 0.05 U I I I I

1 i il l 1 II l mu.

i I I I I I I 0

0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Elapsed Testing Hours Figure 5-3: Displays the chloride concentration of the BWR and PWR baths over the length of the test 27 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Fluoride Concentration 0.06 0.05 0.04 0.03

-.4--BWR

-Ue--PW R 0.02 0.01 0

0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Elapsed Testing Hours Figure 5-4: Displays the fluoride concentration of the BWR and PWR baths over the length of the test 28 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Aluminum Concentration 0.35 0.3 0.25 I

0.2 E

0.5 -4.BWR "4-U-PWR 0.1 0.05 !

0 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Elapsed Testing Hours Figure 5-5: Displays the aluminum concentration of the BWR and PWR baths over the length of the test 29 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 Sulfate Concentration 1.6 1.4 1.2 E0.8 0.

--4--BWR

-,1- PWR 0.6 0.4 0.2 0

0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Elapsed Testing Hours Figure 5-6: Displays the sulfate concentration of the BWR and PWR baths over the length of the test 30 Curtiss-Wright \ Nuclear Division \ NETCO

NET-300047-07 Rev 1 EGD NO.: 28079-003, Rev. 1 PWR Boron Concentration 3000 2500 2000 S1500 1000 0

0 2000 4000 6000 8000 10000 12000 14000 Elapsed Testing Hours Figure 5-7: Displays the boron concentration of the PWR bath over the length of the test 31 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 5.3 Test Matrices and Coupon Descriptions The test matrix for this corrosion test is basic and being used for a general understanding of material performance over an extended service life. Two different types of MAXUS materials are being examined in this experiment, a 21% boron carbide content material and a 40% boron carbide content material. Coupons will be placed in the general configuration and the encapsulated configuration to simulate the two most prominent spent fuel pool conditions for a neutron absorbing material. Table 5-1 contains the details of the testing batch.

All coupons rest in a PTFE holding rack. The general coupons sit in the rack, open to the water. Encapsulated coupons sit in a stainless steel 304L capsule which simulates wrapper plate conditions in spent fuel pools. The previous coupon types described are approximately two (2) inches by four (4) inches. The 21% B4C content coupons are approximately 0.08 inches thick, while the 40% B4C content coupons are approximately 0.10 inches. Coupons undergo pre-characterization testing and post-characterization testing as scheduled in Table 5-2.

Table 5-1: Shows the tally for each coupon type. Each bath holds coupons as seen in table below for a total of 8 coupons in the one year test batch.

Typ of Coupon 21 w/o 40Owlo General Encapsulated 1 1 Total 32 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I Table 5-2: Displays required pre- and post-characterization for all test coupons TetPre-Test Characterization I Post-Test Characterization Visual Inspection High Resolution Photography _______ _____

Dimensions Dry Weight Density Neutron Attenuation Pit Characterization ,*

Blister Characterization *

If anomaly occurs 5.4 Corrosion Test Results 5.4.1 Visual inspection All coupons were subjected to a visual inspection upon removal from the corrosion baths as well as after the cleaning process. High resolution photographs were taken of all coupons upon removing from the bath. Coupons do not show signs of general corrosion, but do show localized corrosion or pitting. The degree of pitting is very dependent on each coupon's test configuration. Coupons that were placed in the PWR simulated bath experienced more pitting than the coupons in the BWR simulated bath.

33 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300041-07 Rev 1 5.4.2 Areal Density The B1 ° areal density is measured using neutron attenuation testing. Coupons were measured in accordance to NETCO procedures SEP-300047-02 Rev 0 and SEP-300047-03 Rev 7. The areal density was measured before the corrosion test was performed and after coupons were removed from the baths. The results from the one year and two year tests are displayed in Table 5-3 and 5-4. The change in areal density was within the bounds of the uncertainty of the measurements. Therefore there was no measureable effect on the areal density to this point in the testing.

Table 5-3: Displays boron-lO areal density measurements for the one year test coupons

[g.B 10/cm 21 Coupon Areal Density Pre- Uncertainty Areal Density Post- Uncertainty Difference ID Characterization (30) Characterization (30) 2BG1 2BE1 0.0146 0.0007 0.0145 0.0007 -0.0001 2PE1 0.0139 0.060.0139 0.0006 0.0000 4BGI 4BE1 0.0313 0.010.0315 0.01 0.0002 4PE1 0.0324 . 0.0011__ 0.0321 0.0011 -0.0003 Table 5-4: Displays boron-1O areal density measurements for the two year test coupons

[g.B 10 /cm 2]

Coupon Areal Density Pre- Uncertainty Areal Density Post- Uncertainty Difference ID Characterization (30) Characterization (3o) 2BG2 2BE2 0.0141 0.0006 0.0140 0.0006 -0.0001 2PG2 2PE2 0.013 0.0006 0.0139 0.0006 0.0002 4BG2 4BE2 0.0311 0.0011 0.0312 0.0011 0.0001 4PG2 - -

4PE2 0.0324 0.0011 0.0329 0.0012 0.0005 34 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 5.4.3 Corrosion Rate All corrosion rates are displayed in mils (thousands of an inch) per year. Normal service conditions of a spent fuel pool operate around 80°F and during fuel outages can run upwards of 120°F. Since the test baths run at 195°F a correction is made to create an equivalent corrosion rate at the lower temperatures. This equivalency was approximated by creating a ratio using the Arrhenius function. The at-tested temperature of 195°F is approximated to be equivalent to about six (6) years at 120°F and eighteen (18) years at 80°F.[9 ] Most coupons did not show a weight loss. This is significant because a corrosion rate requires a weight loss. Therefore, corrosion rate values for coupons without a weight loss are assumed to be zero. Calculated corrosion rate values are extremely small at less than one thousandth of one thousandth of an inch per year. These values are so small, that they are effectively zero. Since the material's corrosion rate is so small, it is highly dependent on small variations in the balance from pre-bath to post-bath. These variations could be due to variation in the balance and internal corrosion on the coupons.

Table 5-5: Displays equivalent corrosion rates for 80 0F and 120° F pools COUPON CORROSION RATE 120°F CORROSION RATE 80°F General Encapsulated 0.000 0.000 4000 hr. BWR ...

PWR -0.001 0.000 General Encapsulated 0.000 0.000 1 year BWR PWR 0.000 0.000 General 2 year Encapsulated0.0000 BWR PWR 0.000_________ 0.000_____

35 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 5.5 Discussion of Accelerated Corrosion Results The MAXUS material's performance has been shown to be satisfactory. Corrosion rates have been shown to be very small or even zero. The corrosion that has occurred is shown to be localized in the form of pitting. The pitting in MAXUS coupons is observed only in small pockets where the local chemistry becomes ideal. If there is a higher area of flow, for example, being exposed to the open circulating water, the local chemistry is constantly being refreshed and therefore rarely is able to generate the necessary conditions for pitting. However in localized stagnation points, or areas of low flow, pitting is prevalent. These pits seem to be resultant of crevice geometry and thus are more frequent in encapsulated coupons compared to general coupons. This process is accelerated by a lower pH water bath (PWR).

As a neutron absorber the most important property is the ability of the material to provide the specified reactivity hold-down. MAXUS material had no change in Boron-10 areal density over the test duration. At the conclusion of the 2 nd year of testing, MAXUS material shows positive performance. This performance is supported through the testing results, such as corrosion rate, boron-l0 areal density measurement, and pit sizes.

References for Section 5.0 5-1. NET-300047-01 Rev 0 "Project Plan: Long-Term Accelerated Corrosion Test Program for MAXUS AI/B 4 C Metal Matrix Composite." NETCO Lake Katrine, NY 2012.

5-2. SEP-300047-01 Rev 0 "Procedure for Accelerated Corrosion Testing of MAXUS Coupons." NETCO Lake Katrine, NY 2012.

5-3. SEP-300047-02 Rev 1 "Procedure for Pre-characterization of Accelerated Corrosion Coupons" NETCO Lake Katrine, NY 2013.

5-4. SEP-300047-03 Rev 4 "Procedure for Post-Test Characterization of the Accelerated Corrosion Coupons." NETCO Lake Katrine, NY 2014.

5-5. ASTM G31 -72 (Reapproved 2004), Standard Practice for Laboratory Immersion Corrosion Testing of Metals.

5-6. ASTM G46-94 (Reapproved 2005), Standard Guide for Examination and Evaluation of Pitting Corrosion.

36 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I 5-7. Godard, Epson, Bothwell and Kane, The Corrosion of Licqht Metals, John Wiley &

Sons, Inc., New York, 1967.

5-8. Boral 5 Year Test-NRC Neutron Absorber Mtg 10-4-12. Keith Waidrop.

Accession Number: ML12283A046.

37 Curtiss-Wright \ Nuclear Division \ NETCO

Enclosure Description and Assessment of Proposed License Amendment ATTACHMENT 7 Westinghouse Application for Withholding ProprietaryInformation from Public Disclosure, CAW-1 5-4271, September 3, 2015

(~)Westinghouse Westinghouse Electrc Company "1000 Westinghouse Drive Cranberry Township, Pennsylvania 16065 USA U.S. Nuclear Regulatory Commission Direct tel: (412)374-4643 Document Control Desk Direct fi'x: (724) 940-8560 11*55 Rockville Pike e-mail: greshaja~westinghousexcom Rockville. MD 20852 Proj l*ete NF-APS-I 5-67 CAW-l 5-4271 September 3, 2015

APPLICATION FOR WIT-HH*OLDING PROPRIETARY INFORMATION FROM.PUBLIC DISQLQSURLE

Subject:

WCAP-18030-P, Revision 0, "Criticality Safety Analysis for Palo Verde Nuclear Generating Station Units 1,2, and 3" (Proprietary)

The proprietary information fouwbich withholding is being requested in the above-referenced report is thrtber identified in Affidavit CAW-15-4271 signed by the owner of the proprietary information, Westinghouse Electric Company LLC. The Affidavit, which. accompanies this letter, sets forth* the basis on which~the~information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragr'aph (b)(4) of 10 CFR Section 22390 of the Commission's regulations.

Accordingly, th~is letter authorizes the utilization of the accompanying Affidavit by Arizona. Public Service Company.

Correspondence with respect to the proprietary aspects of the Application for Withholding or the Westinghouse Affidavit Should reference CAW-15-4271 and should be addressed to James A. Greshaim.

Manager, Regulatory Cbnmphanee, Westinghouse Electric Company, 1000 We~stinghouse Drive, Bufilding 3 Suite 310, Cranberry Township, Pennsylvania. 16066.

A. Gresham, Manager Regulatory Compliance

CAW-15-427 1 September 3, 2015 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:

5$

COUNTY OF BUTLER:

t James A. Gresham, am authorized to execute this Affidavit on .behalf of Westinghouse Electric Company LLC (Westinghouse), and that the averments of fact set forth in this Affidavit are true and correct to the best of my knowledge, information, and belief.

,James A. Greslham, Manager Regulatory Compliance

. 2CAW-15-4271 (1) 1 am Manager, Regulatory Compliance, Westinghouse Electric Company tLC (Westinghouse),

and as such, I have been specifically delegated the function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rule making proceedings,-and am authorized to apply for its withholding on behalf of Westinghouse.

(2) 1 am making this Affidavit in conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations and in conjunction with the Westinghouse Application for Withholding Proprietary. Information from Public Disclosure accompanying this Affidavit.

(3) 1have personal knowledge of the criteriaand procedures utilized by Westinghouse in designating information as a trade secret, privileged or as confidential commercial or financial information.

(4) Pursuant to the provisions of paragraph (b)(4) of Section 2.390 of the Commission's regulations, the following is furnished for consideration by the Commission in detenniningwhether the information sought to be withheld from public disclosure should be withheld.

(i) The information, sought to he withheld from public disclosure is owned and has been held in confidence by Westinghouse.

(ii) The information is of a type customarily held in confidence by Westinghouse and not customarily disc~losed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence. The application of that system and the substance of that system constitute Westinghouse policy and provide thle rational basis required.

Under that system, information. is held in confidence.if it fulls hnone or more of several types, the release of which might result in the loss of an .existing or potentialcompetitive advantage, as follows:

(a). The~information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.)-where prevention of its use~by any of

3 3 ~CAW-15-4271 Westinghouse's competitors without license from Westinghlouse constitutes a comp~etitive economic advantage over Oilher companies.

(h) It consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), the application of which data secures a competitive economic advantage, e.g., by optimization or improved marketability.

(c) Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.

(d) It reveals cost or price information, production capacities, budget Levels, or comtmercial strategies of Westinghouse, its customers or suppliers.

(e) It reveals aspects of past, present, or future Westinghouse or customer fuinded development pLans and programs of potential commercial value to Westinghouse.

(f) It contains patentable ide.as,. for which patent protection may be desirable.

(iii) There~are sound policy reasons behind the WeStinghouse system which include the following:

(a) The use of such information by Westinghouse gives Westingh~ouse a competitive advantage over its competitors. It is, therefore, withheld from disclosure to-protect the Westinghouse competitive position.

(b) It :is information that is marketable in many ways. The extent to which such information is available~to comnpetitors diminishes the Westinghouse ability to sell products and services involving the use of the information.

(c) Use .byour competitor would put Westinghouse at a competitive disadvantage by reducing hisexpenditure of resources at our expanse.

4 4 ~CAW-t15-4271 (d) Eache component of proprietary-information pertinent to a particular competitive advantage is potentially as valuable as the total competitive advantage. If competitors acquire components of proprietary infonnation, any one component may be the key to die entire puzzle, thereby depriving Westinghouse of a competitive advantage.

(e) Unrestricted disclosure would jeopardize the position of prominentce of Westinghouse. in the world market, and thereby give a market advantage to the competition of those countries.

(t) The Westinghouse capacity to invest corporate assets in research and development-depends upon the success in obtaining and maintaining a competitive advantage.

(iv) The information is being transmitted to the Commission in confidence and* under the provisions of 10 CER Sectioni 2.390, it is to be received in confidence by the Commission.

6v) The information-sought to be protected is notavailablein public sources or available information has not been previously employed in thie same original manner or method to the best of our knowledge and belief.

(vi) The proprietary information sought to be withheld in this submittal is that which is appropriately marked in WCAP-18030-P, Revision 0, "Criticality Safety Analysis~for Palo Verde Nuclear Generating Station Units 1,2, and 3" (Proprietary), dated September 2015, for submittal to the Commission, being transmitted by Arizona Public Service Company letter and Application for Withholding. Proprietary Inforniation from Public Disclosure, to the Document Control Desk. The proprietary information as submitted by Westinghouse is that associated with Westinghouse's request for NRC approval of WCAP-1 8030, and may be used only for-that purpose..

5 5 ~CAW-15-4271I (a) This information is part of that which will enable Westinghouse to:

(i) Obtain NRC approval of WCAP-l 8030, "Criticality Safety Analysis for Palo Verde Nuclear Generating Station Units 1, 2, and 3".

(b) Further this information has substantial commercial value as follows:

(i) Westinghouse plans to sell the use of similar information to its customers for thle purpose of demonstrating the sub~critieality of the spent fuel pool.

(ii) Westinghouse can sell support and defense of industry guidelines and acceptance criteria for plant-specific applications.

(iii) The information requested to bcwithheld reveals the distinguishing aspects of a methodology which was developed by Westinghouse.

Public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because itwould enhance the ability of competitors to provide similar technical evaluation justifications and licensing defense services for commercial power reactors withourt commensurate expen~ses. Also, public disclosure of the information would enable others to use die information to meet NRC requirements for licensing documentation without purchasing the right to use the information.

The development Of the technology described in part by the information is the result of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sumn of money.

In order for conipetitors of Westinghouse to duplicate this informnation4 similar technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended.

Further the deponent sayeth not.

PROPRIETARY ]iN'FORMATION NOTICE Transmitted .herewith are proprietary and/or non-proprietary versionsand of documents furnished to the NRC in connection with requests for generic and/or plant-specific review approval.

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WITHHOLD FROM PUBLIC DISCLOSURE UNDER 10 CFR 2.390 Enclosure Description and Assessment of Proposed License Amendment ATTACHMENT 8 Criticality Safety Analysis for Palo Verde Nuclear Generating Station Units 1, 2, and 3 (Proprietary), WCAP-1 8030-P, Revision 0, September 2015

Enclosure Description and Assessment of Proposed License Amendment ATTACHMENT 6 Material QualificationReport of MAXUS for Spent Fuel Storage, NET-300047-07 Rev 1, November 2015

Nuclear Division CURTISS WRIGHT-NETCO 44 Shelter Rock Rd., Danbury, CT 06810 T: 203.448.3310 I F: 203.437.6279 http://scientech.cwfc.com NET-300047-07 Rev. 1 I EGD NO.: 28079-003, Rev. 1 Material Qualification Report of MAXUS for Spent Fuel Storage Prepared by:

NETCO Business Segment Scientech, Nuclear Division 44 Shelter Rock [

Danbury, CT 06811 Rev: Date: J Prepared by: JReviewed by: IApproved by:]

0 10/12/2015 Brian Rickard S. Leuenroth C. Ilioiu Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I TABLE OF CONTENTS LIST OF FIGURES ...................................................................................... II LIST OF TABLES........................................................................................ III

1.0 INTRODUCTION

AND

SUMMARY

............................................................... I

2.0 DESCRIPTION

OF THE NETCO-SNAP-IN AND INSTALLATION TOOLING.............. 3 2.1 NETCO-SNAP-IN INSERT...................................................................... 3 2.2 SYSTEM ANCILLARY EQUIPMENT................................................................... 4 3.0 MANUFACTURING THE NETCO-SNAP-IN NEUTRON ABSORBER INSERT............ 8 3.1 PRODUCTION OF MAXUS....................................................................... 8 3.2 NETCO-SNAP-IN PRODUCTION ................................................................. 8 3.3 QUALITY ASSURANCE............................................................................. 8 4.0 ENGINEERING EVALUATION OF THE MAXUS COMPOSITE ............................ 11 4.1 COMPARISON OF MAXUSWITH BORALTM ................................................... 11 4.2 IN-SERVICE PERFORMANCE OF ALUMINUM MATRIX NEUTRON ABSORBER MATERIAL......... 15 4.3 NETCO EXPERIENCE & CAPABILITIES ............................................................ 22 5.0 ACCELERATED CORROSION TESTING...................................................... 24 5.1 TEST DESCRIPTION ................................................................................ 24 5.2 WATER CHEMISTRY ................................................................................ 24 5.3 TEST MATRICES AND COUPON DESCRIPTIONS ................................................... 32 5.4 CORROSION TEST RESULTS ....................................................................... 33 5.5 DISCUSSION OF ACCELERATED CORROSION RESULTS .......................................... 36 Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev I List of Figures 2-1 NE=TCO-SNAP-IN............................................................................. 3 2-2 Installed NE=TCO-S NAP-IN .................................................................. 4 2-3 NETCO-SNAP-IN Insert Installation Tool with Insert Loaded.............................. 6 2-4 NETCO-SNAP-IN Insert Removal Tool ..................................................... 7 4-1 Comparison of Manufacturing Processes................................................... 13 4-2 Micro Photograph of BORALTM .............................................................. 14 5-1 Displays the pH of the BWR and PWR baths over the length of the test ................. 25 5-2 Displays the conductivity of the BWR and PWR baths over the length of the test ............................................................. 26 5-3 Displays the chloride concentration of the BWR and PWR baths over the length of the test ............................................................. 27 5-4 Displays the fluoride concentration of the BWR and PWR baths over the length of the test ............................................................. 28 5-5 Displays the aluminum concentration of the BWR and PWR baths over the length of the test............................................................. 29 5-6 Displays the sulfate concentration of the BWR and PWR baths over the length of the test ............................................................. 30 5-7 Displays the boron concentration of the PWR bath over the length of the test....................... ................................................... 31 ii Curtiss-Wright \ Nuclear Division \ NETCO

rM~r 'l" AfrlA7 /'A7 D-..., ,I EGD NO.: 28079-003, Rev. 1 I'LsU tV, [r, Iv List of Tables 3-1 Insert Quaiity Assurance Testing Summary.................................................. 9 4-1 Comparison of Aluminum Alloy Matrices .................. ;................................. 11 4-2 Comparison of Boron Carbide............................................................... 12 4-3 Partial Listing of Research and Test Reactors Where BORALTM Has Been Used............................................................................... 16 4-4 Partial List of LWRs Where BORALTM Has Been Used in Spent Fuel Storage Racks ................................................................... 16 4-5 Partial List of LWRs Where BORALTM Has Been Used in Dry Storage Casks ........................................................................... 20 5-1 Shows the tally for each coupon type....................................................... 32 5-2 Displays required pre- and post-characterization for all test coupons .................... 33 5-3 Displays boron-i10 areal density measurements for the one year test coupons /cm2 ] .....................................................................

lo[g-8B 34 5-4 Displays boron-i10 areal density measurements for the two year test coupons [g-B1 °/cm2 ]....................................................................... 34 5-5 Displays equivalent corrosion rates for 80°F and 120°F pools............................ 35 III Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 1.0 Introduction and Summary The purpose of this report is to demonstrate that aluminum-boron carbide sheet called MAXUS, supplied by Nikkeikin Aluminum Core Technology Co., Ltd., is a suitable material for use as a neutron absorber in spent nuclear fuel storage applications, and that in particular, it is a suitable material from which to fabricate NETCO-SNAP-IN neutron absorber inserts. The NETCO-SNAP-IN neutron absorber insert is installed in existing spent fuel storage racks to restore or supplement the reactivity hold-down capability of spent fuel pool racks. Once installed, these neutron absorber inserts become permanently affixed to the storage racks.

The suitability of the MAXUS material as demonstrated herein is based upon:

Detailed comparison with highly similar material with a successful record of industry-wide, in-service performance

Accelerated corrosion testing in simulated BWR and PWR spent fuel pool environments

Evaluating and testing of mechanical properties to verify acceptability of installed insert retention force

Measurement of B10 areal density to confirm satisfactory neutron absorption capability

Long term in-situ coupon surveillance programs.

These evaluations are detailed in the various sections of this report.

MAXUS material is a tightly bound laminated metal matrix composite that is produced using powder metallurgy techniques. This material consists of a 5000 series aluminum alloy outer clad tightly bound to an inner core of 1000 series aluminum reinforced with boron carbide. The boron carbide content varies by weight percent depending on the specified areal density requirements.

As stated above, one particular application of the MAXUS composite in spent fuel pools is the NETCO-SNAP-IN neutron absorber insert. The NETCO-SNAP-IN is proprietary to NETCO and is protected by U.S. Patent No. 6,741,669 B2 [1-. The NETCO-SNAP-IN inserts have been installed and licensed at Exelon's LaSalle, Peach Bottom, and Quad Cities nuclear plants, all of which are BWR plants. The first use of NETCO-SNAP-IN absorber inserts in a PWR spent fuel pool will be at Arizona Public Service Co.'s Palo Verde Station, Units 1, 2, and 3.

Guidance has been published for the qualification and acceptance of new boron based metallic neutron absorbers for storage and transportation casks. [1-2] Using this 1

Curtiss-Wright \ Nuclear Division \ NETCO

EGD NO.: 28079-003, Rev. 1 NET-300047-07 Rev 1 document as a guide, the qualification process described in this report consists of the following elements:

Review of the composition and manufacturing process of the MAXUS composite and a detailed comparison with the composition and manufacturing process for BORALTM, a neutron absorber material that has been successfully used extensively worldwide for spent nuclear fuel storage racks for the last 40 years.

An accelerated corrosion program has been completed in both demineralized water and boric acid (2500 ppm as boron). The program ran for two years in duration. Interim and final results are reported.

A long term surveillance assembly will be placed in the Palo Verde pools prior to the installation of the first NETCO-SNAP-IN inserts. The assembly will hold the following types of coupons o MAXUS composite coupons o MAXUS composite coupons coupled with 304 stainless steel, Inconel 718, and Zircaloy samples o MAXUS composite bend coupons The following sections of this report describe: