ML20140G203

Responds to 970329 Request to Review & Provide Comments on Gaseous Diffusion Plants RTM-96 Supplements

ML20140G203
Person / Time
Site:	Portsmouth Gaseous Diffusion Plant, 07007001
Issue date:	05/02/1997
From:	Weber M NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
To:	Ting P NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
Shared Package
ML20140G210	List: ML20140G203 ML20140G211
References
NUDOCS 9705080108
Download: ML20140G203 (2)

Text

. , May 2, 1997 N a MEMORANDUM T0: Philip Ting, Chief  !

Operatiou Branch Divisior, of' Fuel Cycle Safety and Safeguards, NMSS FROM: Michael Weber, Chief Original signed by:  !

Licensing Branch  ;

Division of Fuel Cycle Safety l and Safeguards, NMSS l

SUBJECT:

REVIEW 0F DRAFT RTM-96 SUPPLEMENTS FOR PADUCAH AND PORTSHOUTH GASE0US DIFFUSION PLANTS (GDPs)

This is in response to your March 29, 1997, request to review and provide comments on the GDPs' RTM-96 supplements. Due to our work load, only a limited 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> review was done.

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One concern noted with the supplements is with Section 9.0, " Technical Basis." l It is not clear what all the assumptions were for the models used for the 1 hydrogen fluoride (HF) intake-versus-distance and the uranium dose-versus-distance figures for the uranium hexafluoride (UF6 ) releases. Section 9.0 seems to indicate that the UF 6releases are based on one-hour exposures to both the HF and uranyl fluoride (UF). This is a very unrealistic assumption,  ;

since a plume of UF6 and hydrolysis products (HF and UF) would be visible and l have a strong bitter odor, and would burn the eyes and nose. It is hard to l imagine anyone staying in this environment for a few minutes, much less one-hour, unless they are trapped like the individual who was killed at the Sequoyah fuels facility. Furthermore, as indicated on pages 8-1 and 8-2, the odor threshold for HF is very low (0.033 to 0.133 ppm) compared to the toxic level (30 ppm), which requires immersion in an obvious and discernable HF plume. '

A further concern noted with Section 9.0 is that it is not clear what happens to the UF. The models seem to be based on the assumption that the UF is carried up with the UF6plume and that none is deposited out. Studies indicate that a large percentage of the UF would ap_t be carried up with the plume but would be deposited close to the release point. Thus, if the models assume all of the UF is taken up in the plume, the uranium dose-versus-distance figures would be very unrealistic.

If you have any questions regarding these comments, please contact Ed Flack, who reviewed the RTM-96 supplements for FCLB. ,

Distribution:

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NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20066-0001

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,,,g* May 2, 1997 MEMORANDUM T0: Philip Ting, Chief Operations Branch Division of Fuel Cycle Safety and Safeguards, NMSS FROM: Michael Weber, Chief /

Licensing Branch Division of Fuel Cycle Safety and Safeguards, NMSS

SUBJECT:

REVIEW 0F DRAFT RTM-96 SUPPLEMENTS FOR PADUCAH AND PORTSMOUTH GASEOUS DIFFUSION PLANTS (GDPs)

This is in response to your March 29, 1997, request to review and provide comments on the GDPs' RTM-96 supplements. Due to our work load, only a-limited 2 hour2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> review was done.

One concern noted with the supplements is with Section 9.0, " Technical Basis."

It is not clear what all the assumptions were for the models used for the hydrogen fluoride (HF) intake-versus-distance and the uranium dose-versus-distance figures for the uranium hexafluoride (UF6 ) releases. Section 9.0 seems to indicate that the UF6 releases are based on one-hour exposures to both the HF and uranyl fluoride (UF). This is a very unrealistic assumption, since a plume of UF6 and hydrolysis products (HF and UF) would be visible and have a strong bitter odor, and would burn the eyes and nose. 'It is hard to imagine anyone staying in this environment for a few minutes, much less one-hour, unless they are trapped like the individual who was killed at the Sequoyah Fuels facility. Furthermore, as indicated on pages 8-1 and 8-2, the odor threshold for HF is very low (0.033 to 0.133 ppm) compared to the toxic level (30 ppm), which requires immersion in an obvious and discernable HF plume.

A further concern noted with Section 9.0 is that it is not clear what happens to the UF. The models seem to be based'on the assumption that the UF is carried up with the UF6plume and that none is deposited out. Studies indicate that a large percentage of the UF would D91 be carried up with the plume but would be deposited close to the release point. Thus, if the models assume all of the UF is taken up in the plume, the uranium dose-versus-distance figures would be very unrealistic.

If you have any questions regarding these comments, please contact Ed Flack, who reviewed the RTM-96 supplements for FCLB.

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