There is no authorization code for the Kreludan Mining Corp that works with Neopets. As of 2015, users cannot enter that location with any code they might try.
There is no one explanation for what purpose the mine serves. It may have originally been intended as part of a plot featuring the return of Dr. Sloth, but nothing ever came of it. It is one of the locations in Neopets that either used to be functional and now isn't, or is a location that was intended for an event or activity that never ended up existing. As of 2015, there are many locations like this in Neopets.