Aquifers

Confined – water supply is sandwiched between two impermeable layers. Sometimes called an artesian aquifer because, when a well is drilled into this layer, the pressure will cause water to spurt to the surface without being pumped. This is an artesian well. Unconfined – has an impermeable layer under it but not above it. This is the most common type. Two types:

The top surface of the groundwater is called the water table. The water table depth varies from area to area and fluctuates due to seasonal changes and varying amounts of precipitation. Excessive pumping can also lower the water table. Groundwater is used for drinking water and to irrigate crops. The biggest problem facing well water today is contamination. Leaking underground storage tanks, leaking septic tanks, landfill seepage, animal waste, fertilizer, pesticides, industrial waste, and road salt are common contaminants.

(unbroken solid rock)

Directions for your aquifer Diagram Color the solid rock layers and the bedrock the same color. Color the artesian aquifer and the confined aquifer the same color. Color the unconfined aquifer a different color. Draw a line, using any unused color, that illustrates the upper level of the water table. Directions for your aquifer Diagram

Used for wastewater disposal, aquifer recharge, or solution mining of minerals. http://www.centralilpals.org/injection-wells.html Injection wells