How long are blue print plans good for time wise, like 11 1/2 years old permit was issued for driveway approach maintance?

permit is long since expired. ask building department what to do about it -- you'll want to know if the work was ever completed

the blue prints may or may not be good depending on if it meets current codes, they could have changed since the prints were drawn

permits generally are good for 6 months so you would need to re-apply before beginning work

huh