You will want to grind out the areas with the holes, but not with a belt  
sander. Open them up a little with something more like a dremel tool. Clean 
the  area up and build it back with fiberglass fibers and epoxy. You might 
have to do  this several times to build back to original level. Then, use a 
fiberglass cloth  to repair the whole area. This is a larger repair than just 
filling the holes.  I'm going to guess that something, very hard, made 
contact with your centerboard  trunk. Removing a larger area of bottom paint 
might show more extensive damage  than you are currently seeing.
 
Rummy
 
 
In a message dated 5/31/2011 4:55:19 P.M. Eastern Daylight Time,  
sailingvesselcarmen at gmail.com writes:

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