Longboard repair?

I just got this old Hobbie longboard that has about seven ¼” – 1” places where the outside shell has flaked off therefore exposing the fiberglass underneath. The board is real heavy so I don't know if it’s already water-logged or what? I don't know if I need to do some tests or work on my Hobbie before I take it out for the first time. Mostly I want it in working condition but I’d like to restore it secondly. Whatcha’ think?