~ IOl.1

25 March 2016

Mr. Bernard White, Senior Project Manager U.S. Nuclear Regulatory Commission Office of Nuclear Material Safety and Safeguards Division of Spent Fuel Management 11555 Rockville Pike One White Flint Rockville, MD 20852

Docket: TAC No.:

71-9187 L25090

Dear Mr. White:

QSA Global, Inc.

40 North A venue

Burlington, MA 01803

Telephone: (781) 272-2000

Toll Free: (800) 815-1383

Facsimile: (781) 359-9191

The following is submitted in response to your letter for additional information dated 3/23/16 and our discussion with your staff regarding the current pending submission. It was agreed, for the purposes of the current submission, that QSA Global, Inc. would limit our requested changes associated with this renewal to items 1-7 and item a (minus the material change option) from our letter dated 2/29/16. In response to your RAI questions we provide the following additional information:

I. Weld on Sentry 110 Shield Rings

The Sentry 110 shield rings serve two primary functions. They are used as an aid during assembly by locating the shield at the proper height within the body weldment. And once the assembly is completed, they provide additional support to the primary shield securing mechanisms during use and transport.

The shield rings are positioned between the shield and the top and bottom body weldment endplates. The shield rings are primarily retained in place on the endplates by four tack welds per ring. During final assembly, this construction is further held in place by the addition of the polyurethane foam fill , four endplate rivnuts per plate and assembly compression and friction. All these items contribute to retaining the shield rings in the body weldment in their assembled locations as shown in Figure 1.

In order to move a shield ring from its originally manufactured position to a location where it no longer supports the shield, all of the following would need to occur:

1. All four shield ring tack welds would need to fail. 2. The ring would need to overcome the frictional forces associated with assembly compression. 3. The foam around the ring would need to compress significantly. 4. At least two of the four endplate rivnuts to need to shear.

www qsa - globa l com

Page 2

Figure 1. Welded Body Section View

In the unlikely event a shield ring moves to a location where it no longer supports the shield, the shield would continue to be supported by the titanium shield pins in each of the two welded port assemblies as shown in Figure 2 and on Section A3-A3 on sheet 3 of drawing R86000 revision R enclosed. Figure 2 shows one end of the shield inserted into the back plate ofone welded port assembly.

SHIELD PIN FOAM (SHOWN TRANSPARENT}

Figure 2. Welded Port Section View

www qsa - global com

Page3

Test Plan 180 identified .five drop orientations to consider for the Sentry Series transport packages. Only the TPl SOE orientation, which hit squarely on the top or bottom surface of the welded body, could cause the shield to translate upon impact without the rings present between the shield and endplates.

Assuming the shield rings are not present for this drop orientation, the shield translation upon impact would be limited by the polyurethane foam fill until the design clearance between the shield and the welded port assemblies is consumed. Once the clearance is consumed, the shield ends would rest on the welded port back plate holes and the s_hield mounts in the direction of the impact. Under this drop condition, the 0.19 inch design clearance shown in Figure 2, is equal to the available source wire clearance in the shield source tube. 'fhis results in no movement of the source capsule from its fully shielded position upon impact when dropped under the hypothetical accident condition tests in the TP180E orientation.

Since the shield rings are not relied upon to provide the primary structural integrity of the package under normal or hypothetical accident condition transport, and since additional features exist to prevent movement of the shleld rings after manufacture, the welding of the shield rings is conside~ed to be a manufacturing aid only. As such, allowing a tack weld option for the shield rings to the body endplates will have no adverse impact on the package integrity. Drawing R86000 Revision Ron sheet 2, has been revised to specify that the shield rings tack weld to the endplates is not important to safety (NITS). This change will reflect production welding for units in use, will have no adverse impact on the package integrity, and will not create a substantial safety hazard under 10 CFR Part 21.

Based on our discussion, we have revised our request for Item a. on letter 2/29/16 to read as follows for the large rivnuts:

a. The material specification for the large rivnuts referenced on sheet 2 of drawing R86000 is "NAS 1330N8E-326, Type 316/316 stn stl". The NAS description contains a typographical error as the-326 should be -426. There is also a typographical error in the quantity of large rivnuts specified on the Sentry assemblies. Currently the descriptive specifies 32 large rivnuts when in actuality, the quantity for the large rivnuts is 24 not 32. This was an oversight that was missed during review and approval of the descriptive drawing. These issues are revised on drawing R86000 Revision R enclosed.

Currently, drawing R86000 Revision N identifies two different components on sheets 2, 3 and 8 as "Large Rivnut". To eliminate confusion with the parts referenced on sheets 3 and 8, we have changed the rib attachment rivnuts description on sheet 2 to "Shell Rivnut". Drawing R86000 revision R enclosed revises the rivnut designation on sheet 2 from "LARGE RIVNUT" to "SHELL RIVNUT". In addition, the "TYPE 3 l 6/316L STN STL" is removed from the mat~rial description for this p!1f! since this information is already included in the NAS1330 standard. Revision R of drawing R86.000 has been revised to reflect the changes shown above.

Also, based on our discussion, we have revised R86000 Revision R to remove all changes to Revision P except for those described in Item 1-7 of our letter dated 2/29/16 and Item a. above. Lastly, based on our call we have added "NITS" to the material description for the Lock Pin Springs on sheet 6. ·

The drawing revision associated with these issues is included as an enclosure to this letter. Should you have any additional questions, or wish to discuss this issue or our amendment request, please contact me.

w w w . q s a ~ ·g; o b a I . c o· m

Sincerely,

~ E~SIGNED by Lori Podolak on<-~6!03-2516:49:30 GMT

Lori Podolak Manager, Regulatory Affairs/Quality Assurance Ph: (781) 505-8241 Fax: (781) 359-91°91 Email: Lori.Podolak@gsa-global.com

Enclosures: Drawing R86000 Revision R

cc: ATTN: Document Control Desk

Page4

"~':> E-!SIGNED by Michael Fuller on~2]J._6±'03-25 16:51 :_56_G_M_T __ _

RA/Q~)~oval Date

E.fs~t'J~D by Steve Grenier on'-2016:<03-25 16·55:4~4~G~M~T~--

Engineeri~·Approval Date

Director, Division of Spent Fuel Storage and Transportation Office of Nuclear Material Safety and Safeguards U.S. Nuclear Regulatory Commission 11555 Rockville Pike One White Flint Rockville, MD 20852

www.9sa-global.com