Two things: 1. Explore the depths and see where that EMP blast came from. Try to just find something that may look out of place in an ocean. Including giant tentacles. 2. Start getting a stockpile of seafood sorted out in case there's no backup generator for the fridges and we're standing powerless for more than a day. Any kind of seafood at all. Including giant tentacles.
Anyone who has the gear is welcome to but we'll have to sort out some sort of buddy system in order to make sure we don't get lost anyway, or end up getting left back in case the ship comes on suddenly and starts moving away.