RE: UF6

["Richards, David" <david.richards@rfets.gov>]

While we don't deal with UF6 here at Rocky Flats, we have postulated and
modeled numerous depleted uranium release scenarios in our emergency
preparedness hazards assessments. Oak Ridge certainly will have done the
same thing for their facilities because it is required by DOE orders. These
assessments should be publicly available as they constitute the technical
basis for emergency planning zones and onsite/offsite planning and
preparedness efforts.

As for our analyses, scenarios include spills, fires, explosions,
earthquakes, aircraft crashes, and high winds/tornadoes. Postulated amounts
of materials released to the environment range from 9.88E-5 grams to 62,000
grams. The highest radiological consequence calculated at 30 meters from the
release point (the nearest receptor used for determining emergency
classifications in the DOE realm), is 7.64E-4 rem TEDE (50 yr) or 0.764
millirem TEDE. This does not reach even the lowest level of classifiable
operational emergency (Alert, 1 rem @ 30 meters).

Interestingly, most people tend to "what if" with those tornado scenarios,
but the high wind analyses actually result in the lowest consequences
because of the awesome amount of dispersion that occurs. In essence, aside
from the political ramifications of missing or "highly traveled" rad
material containers and the physical damage typically caused by tornadoes,
they are really one of the "best" types of hazardous material release
scenarios from the standpoint of consequences.

Regards,

DJ Richards
Hazards Assessment & Y2k Emergency Preparedness Team Leader
Rocky Flats Environmental Technology Site
David.Richards@rfets.gov
djrichards@earthlink.net


> -----Original Message-----
> From:	Susan Gawarecki [SMTP:loc%icx.net@inet.rfets.gov]
> Sent:	Wednesday, January 27, 1999 1:38 PM
> To:	Multiple recipients of list
> Subject:	UF6
> 
> I've been following the discussion of the hazards associated with UF6
> with interest.  There are approximately 4700 cylinders of the substance
> stored outside in yards at the K-25 site (or East Tennessee Technology
> Park, ETTP) in Oak Ridge (many more are kept at Paducah and
> Portsmouth).  DOE contends this is a resource, rather than a waste, and
> plans to store it well into the next century in the current form, with
> regular inspection and maintenance of the cylinders.  Many stakeholders
> contend that continued storage of this material is incompatible with the
> current process of "reindustrializing" the K-25 site, that is having
> commercial ventures lease space for a variety of manufacturing or
> service activities.
> 
> Interestingly, three sites that exceeded the primary dose limit for
> gamma levels and are potentially accessible to the public, according to
> Tenn. Dept. of Environment & Conservation DOE Oversight Division, are
> all near the UF6 cylinder storage yards at ETTP.
> 
> While rational people agree that minor leaks are self-healing and that
> this scenario of surveillance and maintenance will allow safe storage
> for many years, we feel that little attention has been paid to the
> potential for catastrophic release from severe weather.  You may have
> heard about the recent tornados which destroyed downtown Clarksville,
> Tenn., and damaged a suburb of Jackson, Tenn.  Several years ago, a
> tornado touched down at the entrance to the Y-12 Plant in Oak Ridge,
> rolling an empty tank (not UF6) off its support and tearing down
> high-tension electric lines along the valley to the NE.  If we were so
> unlucky to have a tornado touch down at K-25, I doubt that the cylinders
> could withstand the stresses (there would be other releases from
> destruction of contaminated buildings, but let's ignore those for the
> sake of simplifying the scenario).
> 
> It's likely that the resulting cloud of HF would pose an immediate local
> danger, but the dispersion of depleted uranium would also be a concern
> to the community. Has anyone modeled (or speculated) on this scenario?
> 
> While on-site conversion of the UF6 to a stable oxide form seems to be
> the preferred alternative by the community, funding constraints may
> force transportation to Paducah, KY, or Portsmouth, OH, for conversion. 
> The structural integrity of the cylinders and the method of handling and
> overpacking them become more significant concerns in that case.
> 
> I would be interested in your professional opinions.
> 
> Regards,
> Susan Gawarecki
> -- 
> ==================================================
> Susan L. Gawarecki, Ph.D., Executive Director
> Oak Ridge Reservation Local Oversight Committee, Inc.
> 136 South Illinois Avenue, Suite 208
> Oak Ridge, Tennessee  37830
> Phone (423) 483-1333; Fax (423) 482-6572; E-mail loc@icx.net
> VISIT OUR UPDATED WEB SITE:  http://www.local-oversight.org
> ==================================================
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