What are four common sources of groundwater pollution?

Here are four common sources of groundwater pollution:

1. Agricultural Runoff: Pesticides, herbicides, and fertilizers used in farming can leach into the groundwater, contaminating it with harmful chemicals and nutrients.

2. Industrial Discharges: Factories and industrial operations may discharge toxic substances, heavy metals, and solvents, which can infiltrate groundwater supplies.

3. Landfills and Waste Disposal Sites: Leachate from landfills can contain a mixture of hazardous materials, including organic and inorganic pollutants, which can seep into groundwater.

4. Septic Systems: Improperly maintained septic systems can leak bacteria, viruses, and nutrients (like nitrogen) into the groundwater.

Two Natural Pollutants:

1. Arsenic: Naturally occurring arsenic can be found in certain geological formations. When groundwater interacts with these rocks, arsenic can dissolve and contaminate water supplies.

2. Radon: This is a naturally occurring radioactive gas that can accumulate in groundwater, especially in areas with uranium-rich geological formations.

How can salt get into freshwater supplies?

Salt can enter freshwater supplies primarily through saltwater intrusion, which occurs when freshwater aquifers are depleted, allowing saltwater from nearby oceans or saltwater bodies to invade the aquifer. Additionally, practices such as road salting (for de-icing), agricultural runoff containing fertilizers with high salt content, and improper waste disposal can contribute to the salinization of freshwater sources.

Where does radon originate?

Radon originates from the natural radioactive decay of uranium found in soil, rock, and water. When uranium breaks down, it produces radon gas, which can seep into the ground and subsequently enter groundwater supplies, particularly in areas with high uranium concentrations in the geological materials.