Question

which method of water treatment is MOST environmentally friendly?​

Answer 1

Answer:

Summary: Sustainable, biological filters called slow sand filters have been used to filter drinking water since the 1800s. They don't use any chemicals, create no waste and use very little energy.

Answer 2

Answer:

Sustainable, biological filters called slow sand filters have been used to filter drinking water since the 1800s. They don't use any chemicals, create no waste and use very little energy.