The Wash Plant is where you wash off dirt to reveal gold nuggets! It has different states, outside of the normal working state:
Sleeping: This is when the wash plant shuts off because there is not enough/ none dirt delivered from resource claims)
Not working: When the building is placed outside the are of work of a generator
Overloaded: Too much dirt is delivered. You must either upgrade your Wash Plant or build another one.
Your Wash Plant(s) will function normally as long as there's enough dirt in your stock piles, and your Wash Plant(s) are placed in areas near electricity.