The sirens need to be yanked from the vehicle (if they exist).
The Secretary of EPA isn’t in the line of presidential succession—even in the event of alien invasion:
https://en.wikipedia.org/wiki/United_States_presidential_line_of_succession
Even the Secretary of Education is higher on the pecking order (subtle reference: Battlestar Galactica :-) ).
He was likely in a SS pool vehicle, all of which are likely equipped.