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About IDPH

Environmental Health Fact Sheets

  • Abandoned Wells An estimated 400,000 private water wells in Illinois provide drinking water to approximately 1.3 million people. Each year, many of these wells are abandoned when they are replaced with new wells or when homes are connected to community water systems. A large number of these abandoned wells are large diameter dug wells constructed with brick or stone casings, and range in
  • Alachlor and Atrazine in Groundwater What are alachlor and atrazine? Alachlor and atrazine are used as selective herbicides for controlling grasses and broadleaf weeds. They are usually applied to the soil surface either before or just after a crop has emerged. Alachlor is used mainly on corn and soybean fields, but also can be used in commercial nurseries. Atrazine is used mainly on corn fields.
  • Arsenic in Groundwater Arsenic is a metal-like substance found in small amounts in nature. Elevated levels of arsenic can be found naturally in groundwater in some areas of Illinois. Arsenic in groundwater may also be the result of contamination caused by hazardous waste or industries that use arsenic. Drinking water containing high levels of arsenic may cause health problems. How Might I be Exposed
  • Bored Wells Water wells must be located and constructed to provide safe water at all times and under all conditions. Bacterial contamination of a water supply generally occurs when seepage from sewage systems or surface water enters the well. Contamination may enter the well through the top or by seeping through the well walls. Tests have shown that bacterial contamination is usually
  • Commonly Found Substances in Drinking Water and Available Treatment Hardness The hardness of water is a measure of the amount of minerals, primarily calcium and magnesium, it contains. Water softening, which removes these minerals from the water, may be desirable if: Large quantities of detergent are needed to produce a lather when doing laundry, or Scale is present on the interior of piping or water tanks, laundry sinks or cooking utensils
  • Drilled Wells Water wells must be located and constructed to provide safe water at all times and under all conditions. Bacterial contamination of a water supply generally occurs when seepage from sewage systems or surface water enters the well. Contamination may enter the well through the top or by seeping through the well walls. Tests have shown that bacterial contamination is usually
  • Driven Wells Water wells must be properly located and constructed to provide safe water at all times and under all conditions. Driven wells are also referred to as sand-point wells. Description of A Driven Well A driven well is a small diameter well, assembled by joining lengths of steel pipe, 1¼ inches or 2 inches in diameter, with threaded couplings. Each section of steel pipe is 4 feet
  • Emergency Hauling, Storing and Disinfecting of Water Supplies Sources of Potable Water Water should be obtained from a municipal water supply. When this is not possible, many food industries, such as milk and beverage plants, have the necessary equipment (i.e., pasteurizers and bottlers) for handling water. In certain emergencies where water from such facilities is not in adequate supply, unprocessed water from private supplies may be
  • Iron in Drinking Water Iron can be a troublesome chemical in water supplies. Making up at least 5 percent of the earth's crust, iron is one of the earth's most plentiful resources. Rainwater as it infiltrates the soil and underlying geologic formations dissolves iron, causing it to seep into aquifers that serve as sources of groundwater for wells. Although present in drinking water, iron is seldom
  • Methane in Groundwater Methane (CH4) is a colorless, odorless, flammable gas used as a fuel to heat homes. Methane is produced in nature by the decay of organic matter and the digestion process of various organisms. Elevated levels of methane can be found naturally in groundwater in some areas of Illinois. Methane in groundwater also may be the result of contamination caused by leaks from
  • Nitrates in Drinking Water Nitrates And Diet Nitrate (NO3) is a compound of nitrogen and oxygen found in nature and in many food items in our diet. Generally, the concentration of nitrates in the ground water is low. The main adult human intake of nitrates is from food rather than from water. Vegetables such as spinach, lettuce, beets and carrots contain significant amounts of nitrate. Drinking water
  • PFAS in Drinking Water Per- and polyfluoroalkyl substances (PFAS) are chemicals produced in the United States since the 1940s. They are used for applications ranging from firefighting to stain and waterproofing of consumer products, such as carpet, clothing, and food packaging. Some PFAS are no longer made due to environmental and human health concerns, but they persist in the environment and may
  • Radium in Groundwater Radium (Ra) is a naturally-occurring radioactive element that can be present in rocks and soil in the earth's crust. Small amounts of radium can also be found in groundwater supplies. Radium can be present in different forms, called isotopes. The most common isotopes in Illinois groundwater are Ra-226 and Ra-228. The main type of radiation emitted by radium is an alpha
  • Vinyl Chloride in Groundwater What is vinyl chloride? Vinyl chloride is a colorless gas that, at high levels, has a mild, sweet odor. Vinyl chloride is a manufactured substance, used mostly to make polyvinyl chloride (PVC) plastic products. Vinyl chloride can enter the air, soil and groundwater following improper disposal of chemical wastes. How can I be exposed to vinyl chloride? The most common way
  • Well Sampling for Coliform & Nitrate Bacteria in Water Bacteria and parasites that cause illness can enter a well in many ways. Whether the contamination comes from the materials and tools used in the well's construction, from septic failures near the well or from feedlot runoff, the bacteria and parasites must be destroyed to ensure safe water. Every new, modified or reconstructed water well including pumps and
  • Radium in Drinking Water What Is Radium? Radium (Ra) is a naturally occurring radioactive element that is present in varying amounts in rocks and soil within the earth's crust. Small amounts of radium also can be found in groundwater supplies. Radium can be present in several forms, called isotopes. The most common isotopes in Illinois groundwater are Ra-226 and Ra-228. The main type of radiation