"Clean, potable water" is exactly that; something you'd drink. Nothing further is required for making brine. No need to boil it, no need to distill it, just stir the ingredients until dissolved, dump into a clean container, put the meat in and weigh down to keep it in the brine. The KISS factor (Keep It Simple.....). Dad used well water for years, the County would test it and it passed. Then he got on city water, they'd test it, and it'd pass. Simple.