I'm building a 17ft Shearwater Kayak and after the second coat of epoxy and sanding the deck and hatch covers I discovered very small white spots remaining in or under the epoxy. Could it be epoxy dust in the weave? Wiping the deck with denatured alcohol didn't remove them. Perhaps they were there earlier and I didn't see them and epoxied over them? I assume if I leave them as is they will show through the varnish. If that's so is there a fix? Thanks in advance for any guidance you may be able to provide. I've read several posts here that have been very helpful but haven't found one yet addressing this issue.