What are some sources of groundwater contamination?
Hundreds of types of potential sources of contamination have been identified. Groundwater problems can originate on the land surface or subsurface through: • chemical storage; • landspreading of sewage treatment plant sludges; • road salt usage and storage; • animal feedlots; • use and spillage of fertilizers and accidental spills; • septic tanks and drainfields; • leakage from underground storage tanks; • leakage from underground pipelines and sewers; • sewage lagoons; • sanitary landfills; • waste disposal in excavations; • sumps and dry wells; • graveyards; • improperly filled and sealed wells; • drainage wells; • mines; • improperly constructed private wells. These sources do not always threaten groundwater supplies. However, unless managed properly, they usually have the potential to do so. The areas surrounding water wells are particularly vulnerable to these sources of contamination, since contaminants discharged in the recharge area of a pumping well may be drawn toward that we
