There is no easy way. If the sealant was installed properly there is a real good chance you will damage the conductors in the conduit as you chip out the sealant. I would first try to chip it out and see how much a PITA that is. If that proves to be a pain I would look into listed,approved unions and a new fitting and just cut the conduit pull out the conductors, fix the conduit ,pull in new conductors, and reseal.
