Private water wells have 3 main issues for owners to consider. Structural, biological and chemical issues. Inspection and maintenance can usually be done by the owner with shallow dug wells. However, deeper drilled well maintenance may require a professional.
Structurally, a well must be made to block all surface water and only allow deeper ground water to be used. Deep water that penetrates through the soil is naturally filtered and should be free of harmful pathogens. However, if rain or surface runoff can enter the well without first passing through the soil then the well is not functioning like it should be. It is a leaky well. Inspect the well cap, seals and the inside of the liner for signs that water is bypassing the soil and entering the well. Seal off any water entrance points.
If the wells structure is sealed then pathogens should not be able to enter the well. This can be tested with bacteriological samples. Test kits can be obtained from Service NL locations. Follow the directions on the sample kit to get your results. Keep in mind that these tests can detect extremely low levels of bacteria and so your finger prints, a cough or even dust can give a false positive. Be very careful while collecting the bottle and refer to the directions. Total coliforms show that surface water maybe entering your well by the ways described above. Total coliforms themselves are not harmful but are used to indicate that your well is not doing its job and could result in pathogens getting into your water. Fecal coliforms are a sign that much more serious contamination maybe occurring. This can be due to a leaky well with a dog or other animal nearby or it could indicate malfunctioning septic systems in the area. If you receive poor results from your submitted test an Environmental Health Officer will call to discuss the situation and advise you further. This is a free public health service.
Chemical issues can be caused by many factors. With drilled wells, naturally occurring deposits in the bedrock can result in high levels of metals in water. Inappropriate building materials can contaminate well water, so can nearby spills and industrial pollution. Dug wells are no different except they are less likely to have metals from bedrock and more likely to be influenced by pollution or spills. Chemical testing is not a free service in this province and only privately owned laboratories can run these tests for you. The Government does maintain a list of approved labs for this purpose. Maps with known “hotspots” are also available on the Government website. The Canadian Drinking Water Guidelines will provide acceptable levels for you to compare your results against and provide information about health effects.