Periodically (when we have a ground fault) we need to reset a 3000A bolt-lok switch on a substation. What level PPE should we be wearing? The bus is rated "extreme danger". The enclosure would be not able to handle the blast. What recommendations do you have?

Hire an assistant

First, I sure hope you are checking the circuit before reclosing.
Second, for a 3000A service are you saying the only GF protection you have is on the main?
Third, really there is no PPE to wear to do this safely, but there are remote operators available.