A hole in my w-s tsunami 160 rotomolded

I was wondering if it is possible to patch a hole about the size of the tip of my thumb that was made by a U bolt on my kayak trailer.Can you melt plastic to cover hole?I am afraid to try without asking first.Hole is not all the way thru-has a deep dent in it.It is a Wilderness Systems Tsunami 160 rotomolded-sugestions would be apreciated. thanks, Ian Taggart