Groundwater
By: Kamryn Calloway
What is groundwater?
Water held underground in the soil or in pores and crevices in rock.
Porosity vs. Permeability
Permeability goes hand in hand with porosity in most cases. The higher the permeability and porosity, the more readily groundwater will flow. You do have cases like limestone where the rock has a very low porosity, but due to fractures may actually have a high permeability.
Diagram
Aquifers come in two types which are shown below: unconfined and confined. Unconfined aquifers are those into which water seeps from the ground surface directly above the aquifer.
What can effect our groundwater supply?
Groundwater contamination occurs when man-made products such as gasoline, oil, road salts and chemicals get into the groundwater and cause it to become unsafe and unfit for human use.
Materials from the land's surface can move through the soil and end up in the groundwater. For example, pesticides and fertilizers can find their way into groundwater supplies over time. Road salt, toxic substances from mining sites, and used motor oil also may seep into groundwater. In addition, it is possible for untreated waste from septic tanks and toxic chemicals from underground storage tanks and leaky landfills to contaminate groundwater.