While the three methods described above will remove only microbes from water, the following two purification methods will remove other contaminates. Distillation will remove microbes, heavy metals, salts, most other chemicals, and radioactive dust and dirt, caused radioactive fallout. Filtering win also remove radioactive fallout. Water itself cannot become radioactive, but it can be contaminated by radioactive fallout. It is unsafe to drink water that contains radioactive fallout.
Distillation involves boiling water and then collecting the vapor as it condenses back to water.
The condensed vapor will not include salt and other impurities. To distill, fill a pot halfway with water. The water that drips from the lid into the cup is distilled. Cover the gravel with a towel cut in a circle slightly larger than the bucket. Cover the towel with six inches of clayish soil dug from at least four inches below ground level.