ML20262H086

Alternative Request Pertaining to American Concrete Institute (ACI) Code for Eos Amendment 1

ML20262H086
Person / Time
Site:	07201042
Issue date:	09/24/2020
From:	Andrea Kock Storage and Transportation Licensing Branch
To:	Narayanan P TN Americas LLC
CJJacobs NMSS/DFM/STL 301.415.6825
References
EPID L-2020-LLR-0120
Download: ML20262H086 (3)

Text

September 24, 2020 Mr. Prakash Narayanan Chief Technical Officer TN Americas LLC 7160 Riverwood Drive, Suite 200 Columbia, MD 21046

SUBJECT:

REQUEST FOR ADDITIONAL ALTERNATIVE TO THE AMERICAN CONCRETE INSTITUTE CODE, CONCRETE TEMPERATURE TESTING IN THE TECHNICAL SPECIFICATIONS FOR EOS CERTIFICATE OF COMPLIANCE NO. 1042, AMENDMENT NO. 1 (DOCKET 72-1042, EPID NO. L-2020-LLR-0120)

Dear Mr. Narayanan:

The purpose of this letter is to communicate the Nuclear Regulatory Commission (NRC) approval of your request to use a test age of up to 56 days as an additional alternative to American Concrete Institute (ACI) 349-06, Appendix E, Section E.4-Concrete Temperatures to allow the use of a later-age specified concrete compressive strength of 7000 psi for horizontal storage module (HSM) fabrication for EOS Certificate of Compliance (CoC) No. 1042, Amendment No. 1. The Technical Specifications (TS) for EOS Amendment No. 1 currently specify a 28-day test age and reference an alternative ACI code (i.e., ACI-349-13). However, ACI 349-13 allows the use of a later designated test age for determination of compliance with the specified strength (common test ages discussed in the ACI code are 56 or 90 days).

By letter dated August 28, 2020 (Agencywide Documents Access and Management System

[ADAMS] Accession No. ML20241A115), TN Americas, LLC (TN) requested an additional alternative to include a test age of up to 56 days to allow the use of the later-age specified concrete compressive strength of 7000 psi for HSM fabrication. TN is proposing an alternative to the alternative ACI 349-13 code for EOS CoC No. 1042, Amendment No. 1. TS 4.0 states that proposed alternatives to the ACI codes may be used when the proposed alternatives are authorized by the Director of the Office of Nuclear Material Safety and Safeguards, or designee.

The TS also state that the applicants request should demonstrate that the proposed alternative provides an acceptable level of quality and safety, or compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.

The applicant stated that previously approved alternative ACI concrete design mixtures in the TS allow a portion of the Portland cement in the concrete mixture to be replaced with other mineral cementitious materials which result in: better concrete workability, easier finishability, higher compressive and flexural strengths, lower permeability (which increases corrosion resistance), and improved resistance to aggressive chemicals. However, one disadvantage is that the material takes longer to cure to reach the required compressive strength of 7000 psi,

P. Narayanan 2 which is why TN has requested more time to reach the compressive strength (i.e., up to 56 days).

As mentioned previously, ACI 349-13 is already approved for use as alternative code specified in TS 4.0. ACI 349-13 allows for other designated test ages, which can be 56 days or even 90 days for the specified concrete compressive strength when similar design mixtures are used.

The proposed changes are similar to the concrete design mixtures previously approved. The only question is whether there is a safety concern by allowing a longer test age beyond the 28 days specified in the TS. The applicant addressed this concern by stating that the HSM array will not be certified and/or loaded with dry shielded canisters (DSCs) until the specified compressive strength of 7000 psi is achieved. Regarding any environmental impact, this proposed change to the alternative only addresses the timing of certain concrete compressive strength testing and would therefore have no environmental impact.

Although the proposed additional alternative to ACI 349-13 (i.e., a test age of up to 56 days) is not specified within TS 4.0 for EOS CoC No. 1042, Amendment No. 1, the proposed alternative is approved because it demonstrates an acceptable level of quality and safety. The staff notes that if the required compressive strength of 7000 psi is not reached by day 56, then the HSM array could not be loaded with DSCs.

If you have any questions regarding this matter, please contact Christian Jacobs, of my staff, at 301-415-6825, or christian.jacobs@nrc.gov. Please reference the EPID number above in any correspondence related to this action.

Sincerely, Christoph Digitally signed by Christopher er M. M. Regan Date: 2020.09.24 For A. Kock Regan 12:32:10 -04'00' Andrea L. Kock, Director Division of Fuel Management Office of Nuclear Material Safety and Safeguards Docket No. 72-1042 EPID L-2020-LLR-0120

P. Narayanan 3

SUBJECT:

REQUEST FOR ADDITIONAL ALTERNATIVE TO THE AMERICAN CONCRETE INSTITUTE CODE, CONCRETE TEMPERATURE TESTING IN THE TECHNICAL SPECIFICATIONS FOR EOS CERTIFICATE OF COMPLIANCE NO. 1042, AMENDMENT NO. 1 (DOCKET 72-1042, EPID NO. L-2020-LLR-0120)

DOCUMENT DATE: September 24, 2020 DISTRIBUTION:

DFM r/f NMSS r/f ADimitriadis, RI BBonser, RII MKunowski, RIII GWarnick, RIV DMarcano, NMSS ADAMS Accession Number: ML20262H086 *via email OFFICE: DFM DFM DFM DFM NAME: CJacobs YKim

• TBoyce

• WWheatley

• DATE: 9/3/2020 9/14/2020 9/14/2020 9/14/2020 OFC: DFM DFM DFM DFM NAME: JMcKirgan

• CRegan for: AKock DATE: 9/18/2020 9/24/2020 OFFICIAL RECORD COPY