Contamination Groundwater
Contamination groundwater (groundwater contamination) occurs when man-made products such as oil, gasoline, road salts and chemicals get into the groundwater and cause it to become unfit and unsafe for human use. Some of the major sources of these products, called contaminants, are septic systems, storage tanks, hazardous waste sites, landfills, and the widespread use of road salts, pesticides, fertilizers and other chemicals.
Storage tanks may contain oil, gasoline, chemicals, or other types of liquids and they can either be above or below ground. There are estimated to be more than 10 million storage tanks buried in the United States and over time the tanks can crack, corrode and develop leaks. If the contaminants leak out and get into the groundwater, serious contamination could occur.
Septic systems can be another serious contamination groundwater source. Septic systems are used by offices, homes or other buildings that are not connected to a city sewer system. Septic systems are designed to slowly drain human waste underground at a slow and harmless rate. An improperly designed, located, constructed, or maintained septic system can leak viruses, bacteria, household chemicals, and other contamination groundwater causing serious problems.
Today in the United States , there are thought to be more than 20,000 known abandoned and uncontrolled hazardous waste sites and the numbers continues to grow every year. Hazardous waste sites can lead to contamination groundwater if there are barrels or other containers around that are full of hazardous materials. If there is a leak, the contaminants can eventually make their way through the soil and into the groundwater.
Landfills are yet another major source of contamination. Landfills are the places that our garbage is taken and buried. Landfills are required to have a protective bottom layer to prevent the contaminants from getting into the water. However, if there is no layer or it is cracked, the contaminants from the landfill (car battery acid, household cleaners, paint, etc.) can make their way down into groundwater.
The widespread use of road salts and chemicals is another source of potential contamination groundwater. Road salts are used in the wintertime to melt ice on roads to keep cars from sliding. When the ice melts, the salt gets washed off the roads and eventually finds its way to the water. Chemicals include products used on farm fields and lawns to kill weeds and insects and to fertilize the plants. When rain comes, these chemicals get washed into the ground and then into the water.
We have to remember that due to groundwater being a part of the hydrologic cycle, contaminants in the other parts of the cycle, such as the atmosphere or bodies of surface water, will eventually be transferred into our groundwater supplies.