GEOLOGY

Detailed explanation-1: -Materials from the land’s surface can move through the soil and end up in the groundwater. For example, pesticides and fertilizers can find their way into groundwater supplies over time. Road salt, toxic substances from mining sites, and used motor oil also may seep into groundwater.

Detailed explanation-2: -Contaminants present in these surface waters can contribute contamination to the ground water system. Some wells rely on arti-ficial recharge to increase the amount of water infiltrating an aquifer, often using water from storm runoff, irrigation, industrial processes, or treated sewage.

Detailed explanation-3: -The soil is also affected by the impure water causing changes in acidity, growth of worms, etc in the soil. All the chemicals in weedicides and pesticides dissolve in water and are washed into water bodies from the fields and even seep into the ground and pollute groundwater.

Detailed explanation-4: -Pesticides and fertilizers applied to lawns and crops can accumulate and migrate to the water table. Leakage from septic tanks and/or waste-disposal sites also can introduce bacteria to the water, and pesticides and fertilizers that seep into farmed soil can eventually end up in water drawn from a well.

Detailed explanation-5: -Groundwater is water contained in or by a subsurface layer of soil or rocks. It is generally less contaminated than surface water because the rocks tend to act as filters to remove some contaminants.