ML20111A239

Attachment 1: HI-STORM Umax Amendment 4 RAI Supplemental Response (non-proprietary)

ML20111A239
Person / Time
Site:	HI-STORM 100
Issue date:	04/13/2020
From:	Holtec
To:	Office of Nuclear Material Safety and Safeguards
Shared Package
ML20111A237	List: ML20111A238 ML20111A239 ML20111A240
References
5021063, CAC 001028
Download: ML20111A239 (1)

Text

Clarification Request for Additional Information Docket No. 72-1040 Certificate of Compliance No. 1040 Amendment No. 4 to the HI-STORM UMAX Canister Storage System Chapter 6 - Shielding Evaluation 6-1 NRC Clarification:

Holtec provided a supplemental response to RAI 6-1 on 12/20/2019 (ML20002A425) stating that it modified the dose rate in Section 5.3.4 of the CoC to be approximately 1.5 times the dose rate reported in the FSAR for both the standard and Version B lids. The staff summarized discussion from the previous clarification call held on 12/6/2019 (ML19345E201) and re-emphasized that a basis/justification for the Technical Specifications (TS) dose rate limits should be provided in the FSAR analysis for UMAX Amendment 4. Staff understands the justification and calculated dose rates in the FSAR (i.e., 66 mrem/hr for the standard lid and 22 mrem/hr for the Version B lid), but was not understanding the connection to the higher dose rate limits (i.e., 90 mrem/hr for the standard lid and 30 mrem/hr for the Version B lid) that Holtec had proposed for the TS. Holtec is planning to provide an additional supplemental response to RAI 6-1 to revise the proposed TS dose rate limits to match the dose rates calculated in the FSAR.

Holtec Response:

The dose limits in 5.3.4.a of the CoC Appendix A are revised to be 66 mrem/hr for the standard lid and 22 mrem/hr for the Version B lid. These are the same calculated dose rate values reported in the SAR Table 5.4.7 and supporting calculation packages.

5021063 Attachment 1