Cal-P Wrote:
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> Directly across the mainline platform track at the
> Roseville,ca Amtrak Depot, yellow sign on post
> with vertical lettering HUTA.
> This is beside/within the big JR Davis-Union
> Pacific yard.
> Searching the acronym and found it is “high threat
> urban area”.
> References to freight cars containing
> sensitive/hazardous material being kept in
> constant custody of railroad or recipient.
> While Roseville, Ca is in an urban area it is not
> a rough area by any measurement.
> Any ideas why the designation and what precautions
> are mandated?
> Thanks,, Cal-P

Here you go. I Googled it for you.

[www.govinfo.gov]