Learn about the different types of contaminants that might put your family at risk.

A common unit of liquid volume; the U.S. gallon has a volume of 231 cubic inches or 3.78533 liters; the British (Imperial) gallon has a volume of 277.418 cubic inches or 4.54596 liters.
grab sample
A single sample of material collected at one place and one time; represents only the specific material at the time and place of sampling.
A natural mineral, primarily composed of complex silicates, which possess ion exchange properties.