Well Contamination

Applicable Regulations:

51, 64, 78


  • 310 CMR 22.00 sets drinking water standards and maximum contaminant levels (MCL).
  • With murmurs of high cancer rates, landfill leachate, pesticides/herbicides, and other aquifer concerns, a data audit was needed.
  • Random audit of Health Department files was performed only to find that most files did not have completed well data.
  • Of approximately 150 files pulled, only 78 water well reports were found and dated from 1994 – 2017 (average = 2004).
    Results were as follows:
  • 1 or More MCL Exceedance
    		80.77%
    Meeting or Exceeding Sodium MCL
    		41.03%
    Corrosive pH (<6.5)
    		62.82%

 Nitrates in Well Water


  • In adults high nitrate levels can cause metheglobinemia.
  • Nitrites can cause the production of cancer-causing N-nitroso compounds, though the EPA has not classified nitrate or nitrite as carcinogenic.
  • In infants less than 6 months of age, severely adverse effects have ben noted (including death) when infants consume formula prepared with drinking water that contains nitrate at levels higher than recommend limits.
  • Consumption by pregnant women is strongly associated with neural tube defects, oral cleft defects, and limb deficiencies in newborns.
  • Nitrates in well water are because of groundwater pollution, often from improper use of pesticides.

Copper in Well Water

  • Copper can cause nausea, vomiting, stomach cramps, and diarrhea.
  • The EPA does not consider copper a carcinogen.
  • Children will experience the same effects as adults, though a small percentage of infants and children may be unusually sensitive to copper.
  • Studies in animals show that ingestion of high levels of copper might cause a decrease in fetal growth.
  • Copper in well water is the result of corrosive water dissolving the pipes.

Sodium in Well Water

  • Sodium is necessary for human life, though it can be toxic in high levels.
  • Excessive salt intake could aggravate chronic congestive heart failure.
  • High sodium levels are also associated with hypertension.
  • In infants, it can cause fluid loss, eventual dehydration, and permanent neurological damage if there is a preexisting gastrointestinal infection.
  • Addition of water containing high levels of sodium to solid food may exacerbate the effects on children and infants.
  • However, all of these conditions occur with excessive intake of sodium not often associated with sodium-contaminated drinking water.
  • Sodium in well water is the result of salt-water intrusion.

Ironin Well Water

  • Death can occur after ingestion of doses greater than or equal to 40mg/kg body weight, though typically death only occurs after ingestion of 200-250mg/kg body weight.
  • Most effects are aesthetic and technical- rusty color, sediment, metallic taste, reddish or orange staining, associated with corrosion.
  • Iron in well water is the result of corrosive water dissolving the pipes.

Corrosive pH in Well Water

  • Any pH less than 6.5 is considered corrosive.
  • The primary concern is of lead and copper from pipes being dissolved in drinking water.
  • If your home was built before 1980, and your well water report shows that your water is corrosive, it is recommended that you look into re-plumbing your home.

Coliform in Well Water

  • While coliform bacteria itself may not cause illness, its presence can be indicative of other pathogens.
  • The pathogens may cause diarrhea, vomiting, dysentery, hepatitis, and can be roundworms and tapeworms that cause diarrhea.
  • Water with coliform present must be boiled for one minute before drinking or using for cooking, and the well must be disinfected.