23-43. Water from springs, wells, or other underground sources that undergo natural filtration will be your safest sources. Any water found in the pipes or containers of abandoned houses or stores will also be free from radioactive particles. This water will be safe to drink, although you will have to take precautions against bacteria in the water.
23-44. Snow taken from 15 centimeters (6 inches) or more below the surface during the fallout is also a safe source of water.