Bill.......you cannot fix this. That is one of the bad things about formica-type counters. Once they are damaged - that is it.
I would check at THD. They have precut counters - fairly cheap - like $80 / 10' length.
That is all you can really do - Sanding will sand right through the color layer - and if you have read my posts on here about painting counter tops......well - you just don't want to go there either.