Why Plug An Abandoned Well?
They are a safety hazard. Each year the Michigan Department of Environmental Quality receives reports of people, mostly children, falling into old wells. Injure or death can result.
They pose a health concern by actions as conduits for contaminants to move from the surface, through the earth's protective formations, into deeper aquifers. Drinking water contamination has been caused by abandoned wells.
They threaten the environment. Deteriorated well casings or open, uncased boreholes allow movement of water between previously separated aquifers. This can degrade water quality. Abandoned wells have also been used for illegal waste dumping.

What Wells Need to be Plugged?
The Well has it's use permanently discontinued.
It is in such disrepair that its continued use for obtaining groundwater is impractical.
It has been left uncompleted.
It is a threat to groundwater resources.
The well is or may be a health or safety hazard.

The DEQ recommends that property owners hire registered well drilling contractors to plug abandoned wells. Registered well drillers have the specialized training and equipment necessary to properly plug abandoned wells. Obstructions need to be removed.