NASA was (still is) exempt from those EPA regulations as a matter of law, and insulaiton from the previous foam insulation was also known to break off.
I believe on a previous flight a hole burned through the wing that was caused by a foam strike. In that case the location wasn’t as critical and the orbiter returned safely.
Halfway decent management could have prevented both Shuttle tragedies regardless of any regulations. The Shuttle was known to be a dangerous design so they should have been diligent.