I know most of these "mess" stories are home related, but I have one that is work related and burned into my brain cells forever.
Back when I was Engineering Manager for a manufacturing plant in Connecticut (during the second oil embargo), I purchased 8,000 gallons of waste oil for our plant steam boilers as No. 6 fuel oil was unavailable. It was a night delivery and the truck driver either put it in the wrong underground tank inlet pipe, or my powerhouse operator was sleeping (or both). We had two underground tanks for boiler fuel and one was already full since we needed to be prepared for additional fuel shortages.
Bottom line was that the powerhouse was adjacent to the newly bric-bracked Naugatuck River and the fuel ran down the side of the powerhouse, across the yard and into a storm drain that led to the River. Being night, and the truck driver and powerhouse operator, either asleep or whatever, the 8,000 gallons of black, heavy oil went into the river and no one saw the remains until sunup. At precisely 6:00 am (aka "sunrise"), I got a frantic call at home from the shop.......EPA, State Police, Connecticut DEP, and the town Mayor were waiting to see me (oh, and my boss the Vice President).
So much for my raise that year!
Besides cleaning rocks along the river bank all summer with college kids, we painted about 25 boats and paid a good fine. Plus, we put alarms on the tank fill system and did a bunch of other remedial stuff. Gotta love those manufacturing plants that are 100+ years old.