Protect Your Water provides the following water vocabulary to familiarize you with key terminology.
Aquifer Performance Test
Artesian (Confined) Well
A well that penetrates through or into an impermeable layer of silt, clay, or rock. The water level in these wells rises above the upper surface of the aquifer due to the pressure in the confined aquifer. If the water pressure is great enough, the well will overflow the top of the land surface or well (flowing artesian).
The surface and subsurface area surrounding a water well or wellfield which supplies a public water system, through which contaminants are reasonably likely to move toward and reach such water well or wellfield within a specified period of time.
Capture Zone Delineation
The determination of the boundaries of the capture zone(s), typically delineated by complex computer groundwater flow programs, involving the input of numerous data, including water levels (heads), pumping volumes, aquifer thickness, transmissivities, recharge values and other aquifer characteristics.
Cone of Influence or Cone of Depression
Any physical, chemical, biological or radiological substance or matter that degrades water quality and/or threatens the safety of its intended use (i.e. drinking water). Some contaminants are only an aesthetic concern, while others are considered hazardous to your health.
A well drilled and installed in a selected location for the purpose of collecting information regarding aquifer characteristics, such as geologic material, hydraulic parameters, water levels and water quality.
Non-point source of pollution
Point source of pollution
PPB (parts per billion)
A ratio used to describe the proportion of one substance to another. In terms of time, 1 ppb is equal to one second in 32 years; also is equal to 1 drop in a 10,000-gallon tank. Also is measured as micrograms per Liter (ug/L).
PPM (parts per minute)
Static Water Level
The rate at which water is transmitted through a unit width of an aquifer under a unit hydraulic gradient. Transmissivity values are typically given in gallons per day through a vertical section of an aquifer one foot wide and extending the full saturated height of an aquifer under a hydraulic gradient of 1 (gpd/ft).
An aquifer with the water table as its upper boundary. Because the aquifer is not under pressure the water level in a well is the same as the water table outside the well. An unconfined aquifer is usually near to the earth's surface causing it to be easily recharged - but contaminated as well.
The zone containing water under pressure less than that of the atmosphere, including soil water, intermediate vadose water, and capillary water. This zone is limited above by the land surface and below by the surface of the zone of saturation (water table).
The top of an unconfined aquifer where water pressure is equal to atmospheric pressure; in other words, the surface between the zone of saturation and the zone of aeration. The water table depth fluctuates with climate conditions on the land surface above and is usually gently curved and follows a subdued version of the land surface topography.
Stormwater is water from precipitation that flows across the ground and pavement when it rains or when snow and ice melt. Stormwater eventually infiltrates through the ground (contributing to groundwater), runs directly into natural surface water features, evaporates or drains into systems of underground pipes or roadside ditches and may travel for many miles before being released into a lake, river, stream or wetland area.