Burning Man is many things.
But as the “leave no trace” rule declares, Burning Man is not a giant garbage can. Everything set up at the start of the week must come down.
To make sure the “leave no trace” rule is upheld, Burning Man relies on a Playa Restoration Team (The “playa” is the land used during the festival).
Crews of people determine which areas have the most trash — or, as Burners call it, “matter out of place,” or MOOP.
They colour-code the areas based on severity, green being the lightest MOOP areas, yellow being moderate, and red being the most moopy — Burning Man’s words, not mine — and have a line of people clean up each area.
Then the transformation back into an ordinary desert is complete.