– Bacteria are common well contaminants.
– A toxic metal, used in many home plumbing systems. (PDF, 752 KB)
Manganese - Common element found in
minerals, rocks, and soil that is naturally found in groundwater but can be
harmful at high levels. (PDF, 67 KB)
– A common contaminant in drinking water, nitrate is used largely in
agricultural and residential fertilizers. (exit DHS; PDF,
Recommendations for people with nitrate contaminated water:
- Avoid drinking water
containing nitrates greater than 10 ppm during pregnancy, and do not
give the water to infants less than 6 months of age or use the water to
prepare infant formula.
- Do not attempt to remove
the nitrate by boiling the water.
- The Wisconsin Division of
Public Health recommends that people of all ages avoid long-term
consumption of water that has a nitrate level greater than 10 ppm.
– Pesticides used on corn, soybeans, other crops can affect water supplies.
Reports published by the Wisconsin Department of Agriculture, Trade
and Consumer Protection.
Sodium - a naturally occurring element commonly
found at low levels in drinking water supplies. (PDF, 23 KB)
Strontium - a mineral that
occurs naturally in the environment (DHS link)
are two radioactive metals that occur naturally in
Wisconsin groundwater. (exit DHS; PDF,
– VOCs can enter wells from leaking underground storage tanks, landfills,
Former Dumps and Landfills - In the past, dumps were
located in areas thought to have little value. These areas include gravel
pits, ravines, swamps or other lands. Some former dumps have contaminated
groundwater used for drinking.
Lead Arsenate Pesticides - This pesticide was
used extensively to control agricultural pests in fruit orchards until the
late 1950s. The pesticide residues bind tightly to the surface soil layer,
where they have remained for decades. As a result, the residues may pose a
human health risk when the land changes from agriculture to other uses
Manufactured Gas Plants - area where fuel was made for
electricity during 1800s to the 1900s. Manufacturing gas from coal generated a lot of waste,
and which still exists in some drinking water today.