The dirtiest job I ever had was when I worked offshore in the Gulf of Mexico as a rigger and anchor handler for Delmar Systems Inc. The most common job task was to attach or detach anchors to oil rigs, so probably the biggest anchors you'll ever see.
There was one job in particular that was more dirty than any other. We were moving a rig so we pulled up its anchors, 6 total. They look like giant torpedoes called an omni-max that are meant to plunge into the gulf mud hundreds of feet. When we pulled them up onto the deck of the boat we worked on the anchors brought a bunch of mud with them and it was slowly ooze off of the anchor leaving the steel deck extremely slippery and very messy. The mud made the deck slippery comparable to ice. There were a few instances where I had to crawl underneath an anchor to grab something or get something out of the way. By essentially laying down on the deck I became saturated in mud and salt water. Also this is the type of job that doesn't stop until the job is done. Fortunately for this job we were working 16 hours and sleeping 8. By the time we had a few anchors on the deck of the boat there was hardly any room for myself and co-workers to maneuver around the the deck of the boat. To give perspective on how dirty this really was, when I started a shift my jeans and dickies shirt were the proper color and dry by the time we were done for an 8 hour break my clothes and skin would be mostly all gray from mud and pretty well soaked from sea water and sweat.