I worked drilling water wells in El Salvador. When we arrived the children had swollen bellies full of worms. I got so sick while I was there that I lost 20 pounds. I couldn't even eat. The only water well was a 30 foot deep open top well full of dead animals.
By the time we left, the village had a 90 foot deep well, drilled by an LS 100, and covered over with cement for sanitation. There were two other work sights that also finished their projects.
There was not a single atheist on any of the teams. We were all Christians.