EVERYDAY SCIENCE

Detailed explanation-1: -Point-source pollution refers to contamination originating from a single tank, disposal site, or facility. Industrial waste disposal sites, accidental spills, leaking gasoline storage tanks, and dumps or landfills are examples of point sources.

Detailed explanation-2: -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-3: -Groundwater sources are beneath the land surface and include springs and wells. As can be seen from the hydrologic cycle, when rain falls to the ground, some water flows along the land to streams or lakes, some water evaporates into the atmosphere, some is taken up by plants, and some seeps into the ground.

Detailed explanation-4: -Underground storage tanks hold toxic material, such as gasoline and waste oil, which contain dangerous substances that can cause cancer and harm developing children. Chemicals in USTs can quickly move through soil and pollute groundwater. There is no safe level of exposure to many of these toxic substances.