seaweed infested with bugs

I just started to fill my new raised beds in preparation for next spring. I started with 1/2 composted horse manure then went to the beach & found dried seaweed & added that. While giving it a little mix I noticed the seaweed was infested with bugs. I don't want to have to truck it away & start again! How can I get rid of the bugs without using chemicals of course. If I composted the pile & got a good heat going would that kill the bugs? What should I do? Thanks