Module 8 — Protecting Your Well From Contamination
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Protecting Your Well From
Contamination
Probably the most important asset on your property is your water well. Unfortunately it
is often misunderstood and taken for granted. This lack of understanding increases the risk
of contamination to the groundwater. Contamination can be a health risk to both people and
livestock. Groundwater is an important resource that needs to be protected.
Contamination of groundwater is hard to detect in early stages. By the time the problem
is obvious, there is little that can be done to remove the contaminant from the system. It can
take a very long time for contaminants to be flushed out, often decades or longer. Prevention
of pollution is the only effective approach.
Often the biggest contamination threats are things in your own backyard. The following
are examples of potential problems and some ways to prevent them.
Poor Well Construction
The fastest way to contaminate groundwater is through a well. A well provides a
direct path for contamination to travel from the surface to the aquifer.
An inadequate well casing or annular seal may allow surface water or contaminated
groundwater to seep along the outside of the casing and enter your well (see Figure 1,
Annulus or Casing Seal).
Unsecure, missing or inadequate well caps provide a direct path for vermin, insects
and other organisms to contaminate the well.
Locating a well in close proximity to possible sources of contamination could have a
negative effect on the water quality
Multi-aquifer well completion allows mixing of water from several aquifers
which may have significantly different water qualities (see Figure 2, Multi-Aquifer
Well Completion).
Prevention:
The best defense is to hire a licensed water well contractor. They must obtain
an approval that authorizes them to drill water wells in the province. To obtain
this approval, they must have a certified journeymen water well driller to
operate each drilling rig. Standards for drilling, construction and reclamation
of wells are outlined in the Water (Ministerial) Regulation of the
Water Act
.
For more information refer
to the Water Wells That Last video series
(
Part II — Managing and Maintaining).