GEOLOGY

Detailed explanation-1: -Industrial discharges, urban activities, agriculture, groundwater pumpage, and disposal of waste all can affect groundwater quality. Contaminants can be human-induced, as from leaking fuel tanks or toxic chemical spills.

Detailed explanation-2: -Groundwater gets polluted when contaminants-from pesticides and fertilizers to waste leached from landfills and septic systems-make their way into an aquifer, rendering it unsafe for human use. Ridding groundwater of contaminants can be difficult to impossible, as well as costly.

Detailed explanation-3: -Contamination of drinking water sources by sewage can occur from raw sewage overflow, septic tanks, leaking sewer lines, land application of sludge and partially treated waste water. Sewage itself is a complex mixture and can contain many types of contaminants.

Detailed explanation-4: -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.