That should be a few thousand dollars to clean up the mess.
Lets see...evacuate a building of 1200 (?) people earning at least $12 per hour, most more... They mill around in the cold for 2 hours waiting for Hazmat. No. A bit more than a few thousand dollars lost here.
Its not the highly paid IRS employees who are exposed to this stuff. Its generally the seasonal employees on the low end of the pay scale who do not do the assessments or audits or have contact with the public who end up exposed.