Cleaning a 25 foot deep well (Czech Republic)

The well cleaners came, a lead man and his assistant, in a van decorated with a “Dr. Voda” (Dr Water) design. They pushed aside the heavy concrete cover then measured the depth - it looked like 9 m but was actually 7.6 m. They pumped out all the water in the well to the field out back. The outflow alternated between muddy and clear and this went on for about 15 minutes. They say the water will not fill back up into the well immediately, so it’s possible to work down there. The assistant outfitted himself in heavy duty full body wetsuit thing. They set up a steel tripod. At the apex of the tripod was a downward facing hook, and from there, the well cleaner was suspended in his harness on the hook and lowered down by steel cable winch. His tools were lowered down after him. Initially, the head guy power washed what he could reach. After the assistant got down there, the steel cable was raised and a bucket with a scraper and a cup were attached to the hook and lowered down. The well worker sent up three buckets of thick mud. The well was about 3 foot wide so in order to do that the assistant had to crouch down without hitting his head and do a lot of scooping. This was a small job; the cleaners work on wells 3 times as deep.