The Dump is a location that first appeared in the episode "Artist Unknown." There is a lot of trash in it, and it is surrounded by high fencing. In "Artist Unknown," SpongeBob hides in a cereal box from Squidward because he thinks that his art is not good enough. The Janitor is one of the employees. This is where Eugene H. Krabs and Sheldon J. Plankton opened their first and only burger store together as revealed in "Friend or Foe."
The Dump looks like any dump. It has mountains of trash and is guarded by a Guard Worm named JK. It is covered with garbage waste. There are also tall metal gates surrounding the area and a sign saying dump in green all capital letters.
When Mr. Krabs and Plankton were kids, this was their base and later location for their restaurant.