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Abandoned/Unused Well
A water well of any age no longer in use, left in a condition of disrepair, or whose construction is left incomplete. If not properly filled and sealed (closed), an abandoned well can serve as a threat to water resources by providing a conduit for pollutants to directly enter and contaminate an entire groundwater supply used for drinking water. An abandoned well is a health and safety hazard.


A situation that occurs when the indoor air pressure is lower than the outdoor air pressure, causing combustion gasses to be pulled back into a space, such as inside a home, instead of being fully exhausted to the outside. Backdrafting is more likely in well-sealed energy-efficient homes, especially when exhaust fans are in use.


Carbon Monoxide (CO)
A combustion byproduct released from a variety of fuel-burning appliances and equipment as well as cars. CO is a pollutant of special concern because it is an odorless, colorless gas that is not easily detectible and can be fatal. CO can be emitted from a malfunctioning furnace, blocked flue pipe, or charcoal grill used indoors. Symptoms of exposure include headaches, dizziness and nausea. Carbon monoxide detector are recommended for homes that have combustion appliances.


In botany and horticulture, deciduous plants, including trees, shrubs and herbaceous perennials, are those that lose all of their leaves for part of the year. This process is called abscission. In Michigan leaf loss primarily coincides with winter - although drought may bring on leaf loss as well.