ML20273A123

Clarification Call Summary Regarding Eos Amendment 2 RAI Responses

ML20273A123
Person / Time
Site:	07201042
Issue date:	09/28/2020
From:	Christian Jacobs Storage and Transportation Licensing Branch
To:	Mathues G TN Americas LLC
CJJacobs NMSS/DFM/STL 301.415.6825
References
CAC: 001028 L-2019-LLA-0078
Download: ML20273A123 (3)

Text

NRC FORM 699 U.S. NUCLEAR REGULATORY COMMISSION DATE OF SIGNATURE (03-2013)

CONVERSATION RECORD 09/28/2020 NAME OF PERSON(S) CONTACTED OR IN CONTACT WITH YOU DATE OF CONTACT TYPE OF CONVERSATION E-MAIL Glenn Mathues 9/15/2020 TELEPHONE E-MAIL ADDRESS TELEPHONE NUMBER INCOMING glenn.mathues@orano.group (410) 910-6538 OUTGOING ORGANIZATION DOCKET NUMBER(S)

TN Americas LLC 72-1042 LICENSE NUMBER(S) CONTROL NUMBER(S)

CoC 1042 EOS Amendment #2 SUBJECT Clarification Call on RAI #1 response for CoC 1042 EOS Amendment #2.

Participants:

TN: Venkata Venigalla, Philippe Pham, Don Shaw, Hoi Yee Tom, Raheel Haloon, Jake Stefanick, Rick Migliore, Ahmed Abir, Glenn Mathues NRC: Christian Jacobs, Richard Chang, Zhian Li, Darrell Dunn, Joe Borowsky, Yong Kim, Tony Rigato Continue on Page 2 ACTION REQUIRED (IF ANY)

TN to provide supplemental information to RAI #1 by the end of October 2020.

Continue on Page 3 NAME OF PERSON DOCUMENTING CONVERSATION Christian Jacobs SIGNATURE NRC FORM 699 (03-2013)

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NRC FORM 699 U.S. NUCLEAR REGULATORY COMMISSION (03-2013)

CONVERSATION RECORD (continued)

SUMMARY

(Continued from page 1)

A clarification call requested by NRC was held on September 15, 2020, with TN Americas LLC (TN) regarding TN's responses to RAIs 4-7, 6-4, 6-5, 8-4, and non-RAI proposed changes #1, #2 and #3. TN provided the RAI responses and new proposed changes on 6/30/2020, which can be found in ADAMS at ML20190A135.

RAI 4-7: The response to RAI 4-7 included updated time periods associated with 61BTH. Therefore, NRC staff requested that the UFSAR reflect those updates. TN indicated they will revise the FSAR.

RAI 6-4: NRC staff requested TN to clarify if fuel assemblies (FA) containing reconstitution rods are allowed to be loaded in the peripheral locations of the DSC and to revise the UFSAR and TS to reflect these limits as necessary. TN agreed to provide an explicit MCNP analysis for 120 reconstituted rods in the periphery and to revise the TS. Also, TN requested to remove the restriction of 5 reconstituted rods per FA in TS. NRC considers the restriction not necessary if TN can provide analysis to support this request.

RAI 6-5: NRC requested TN to justify that the specific power used in the source term calculations is appropriate or revise the source terms and shielding calculations for the HSM-MX system using more appropriate specific power. There was disagreement between NRC staff and TN as to what specific power is appropriate to use. NRC staff believes the number should be higher (i.e.,

approximately 30 MW/MTU), which NRC staff believes would better represent an average of the three cycles of fuel assembly life.

TN used specific power of 25 MW/MTU, which TN claims is more representative and is based on a sensitivity analysis using real industry results. NRC staff agreed that the 25 MW/MTU specific power could be used if TN can demonstrate that a higher number (e.

g., 30 MW/MTU) has negligible impact on the source term.

RAI 8-4:

Part 1: NRC requested clarification on the heat load and the HLZC presented in the UFSAR table 4.9.7-7. TN agreed to resolve the discrepancies in the table.

Part 2: NRC requested TN to clarify why the mechanical properties and a stress analysis under the accident conditions described in Table 4.9.7-7 are not necessary. Alternatively, provide the results of the stress anaylsis and describe the mechanical properties that are used to evaluate the confinement boundary integrity for an accident described in Section 4.9.7 and Table 4.9.7-7 with a DSC fabricated using duplex stainless steel UNS 31803. TN developed an equation of trend for the properties and added a reasonable margin. NRC staff suggested comparing TN's results against "Steel Construction Institute, Design Manual for Structural Stainless Steel, 4th edition, Bershire, UK: Steel Construction Institute, p. 116, 2017."

Part 3: NRC requested TN to clarify the basis for the accident event duration description provided in the response to RAI 8-4, including a discussion of the effects of prolonged exposures of materials to elevated temperatures. TN agreed to do an accident event evaluation and provide clarification to include addressing the hours discussion, the maximum shell temperature, and the corrective actions to take to return to a safe condition.

Part 4: NRC requested TN to clarify the important to safety functions of the DSC basket aluminum alloy transition rails relied upon for the accident conditions described in Section 4.9.7 and Table 4.9.7-7 and the effects of temperature on the safety functions of the DSC basket transition rails. TN indicated they have all the properties to do an evaluation. TN stated that air circulation would be initiated "as soon as possible", and other corrective actions would be taken. NRC staff mentioned that a catch all phrase of "as soon as possible" is not helpful, because it can be interpreted differently by different people. NRC staff stated that when TN writes about the corrective actions in Chapter 12, TN needs to express some urgency to restart the fan since there is some impact on materials being at high temperatures for long periods. NRC also pointed out that material properties decrease very rapidly at increased temperatures, even for a solid rail. TN stated they are aware and will incorporate in their response. NRC stated that how the rail is constructed is important, and it is important for TN to provide that, especially if TN is relying on this for ITS function. TN indicated the limiting factor is the fuel cladding temperature, but understood NRC staff's concerns and will address in their supplemental response.

Proposed non-RAI change #1: TN proposed that the source term limit for the control components (CCs) to be loaded in the 37PTH canister be relocated from the TS to the UFSAR. NRC requested TN to demonstrate that the CCs only contribute approximately 4%

to the dose for a real individual at the controlled area boundary and the workers inside the controlled area boundary for the ISFSI under normal/off-normal operations and design basis accident conditions. TN stated they will withdraw propose non-RAI #1 change request and will keep the source term limit for the CCs in the TS.

NRC FORM 699 (03-2013)

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NRC FORM 699 U.S. NUCLEAR REGULATORY COMMISSION (03-2013)

CONVERSATION RECORD (continued)

ACTION REQUIRED (Continued from page 1)

Proposed non-RAI change #2: NRC requested TN to provide the method used to convert the source terms of the CCs to equivalent Co-60 source term with justification that the method will be appropriate for all CCs to be stored in the PWR fuel canisters so that the GLs can use the method to determine which CC(s) with what exposure and cooling time can be loaded in the 37PTH canister. TN agreed to add explicit methodology in the UFSAR regarding the Co-60 equivalent source. The NRC staff stated that TN needs to address concerns regarding the different exposures and cooling times for different CCs as discussed during this call with TN.

Proposed non-RAI change #3: NRC staff requested TN to provide a drawing of the Integrated Inner Top Cover Plate and Shield Plug that includes: 1) Dimensions of the intergrated component, and 2) Material specifications. TN indicated they will provide a detailed drawing with the requested information.

Any correspondence or transmittal of supplemental information should include the following:

CAC: 001028 Docket: 72-1042 EPID: L-2019-LLA-0078 NRC FORM 699 (03-2013)

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