Some human activities that can pollute ground water include:
- Improper use of fertilizers, animal manures, herbicides, insecticides, and pesticides
- Improperly built or poorly located and/or maintained septic systems for household waste water
- Heavy construction and mining
- House plumbing involving certain materials such as lead and copper
- Leaking or abandoned underground storage tanks and piping
- Storm water drains that discharge chemicals to groundwater
- Improper disposal or storage of hazardous household wastes
- Chemical spills at local industrial sites.
Bacteria and nitrates. These pollutants are found in human and animal wastes. Septic systems must be carefully maintained and animal manures managed to prevent pollution. Sanitary landfills and garbage dumps are also sources. Children and some adults are at extra risk when exposed to waterborne bacteria. These include the elderly and people whose immune systems are weakened due to, for instance, to a chronic illness or treatments for cancer. Fertilizers can add to nitrate problems. Nitrates cause a health threat in very young infants called “blue baby” syndrome. This condition disrupts oxygen flow in the blood.
Fertilizers and pesticides. The chemicals used in these products may end up in groundwater. Such pollution depends on the types and amounts of chemicals used and how they are applied. Local environmental conditions (soil types, seasonal snow, and rainfall) also have an affect. Many fertilizers contain forms of nitrogen that can break down into harmful nitrates. Some underground agricultural drainage systems collect fertilizers and pesticides. This polluted water can pose problems to groundwater and local streams and rivers. In addition, chemicals used to treat buildings and homes for termites or other pests may also pose a threat.
Heavy metals. Activities such as mining and construction can release large amounts of heavy metals (including radioactive uranium) into nearby groundwater sources. Some older fruit orchards may contain high levels of arsenic, once used as a pesticide, and bromine. At high levels, these metals pose a health risk.
Industrial products and wastes – Many harmful chemicals are widely used in local business and industry. These can become drinking water pollutants if not well managed. The most common sources of such problems include factories, gas stations, dry cleaners, leaking underground storage tanks and piping, and landfills and waste dumps.
Household wastes. Improper disposal of many common products can pollute groundwater. These include cleaning solvents, used motor oil, paints, and paint thinners. Even soaps and detergents can harm drinking water. These are often a problem from faulty septic tanks and septic leaching fields. Here are some tips:
#1 – Identify hazardous substances
#2 – If in doubt, check with your local waste authority
#3 – Ask your local waste authority about proper disposal
#4 – Don’t put hazardous substances down the drain or in the garbage
#5 – Store hazardous materials properly in sealed containers and secure places
#6 – Don’t over apply fertilizers, weed killers, or pesticides.
Lead and copper. Household plumbing materials are the most common source of lead and copper in home drinking water. Corrosive water may cause metals in pipes or soldered joints to leach into tap water. Your water’s acidity or alkalinity (measured as pH) greatly affects corrosion. Temperature and mineral content also affect corrosiveness. Lead can cause serious damage to the brain, kidneys, nervous system and red blood cells. Even in relatively low amounts, these metals can be harmful.
Learn more about the U.S. EPA’s maximum contaminant levels for various substances.