Repair STP import

 From:  davetwo (RFANONI)
7085.1 
Hi,
I've successfully imported a .stp file that I've been supplied.
But there are small areas where the surface has gaps/tears.
Is there an easy way of repairing these? My MoI skills are pretty basic so sorry if this is obvious!
It's to be exported to a mesh so if any export options help that would be OK too.

Thanks in advance.