GROUNDWATER

Water table

• Zone of aeration- pore spaces filled with air

• Zone of saturation- pore spaces filled with water

• Dividing line is called the water table

Zone of aeration

Zone of saturation

Water table

Groundwater affects surface water

Groundwater entering surface water

Permeability

permeability

• http://techalive.mtu.edu/meec/module06/Permeability.htm

Groundwater speed

• http://techalive.mtu.edu/meec/module04/GroundwaterSpeed.htm

AQUIFERS

• Ogallala Aquifer! • Saturated layer (below water table)

• Need interconnected pores (High permeability)

• Ogallala aquifer-”fastest disappearing aquifer in the world”

WELLS

• Need permeable layer• Under water table

http://techalive.mtu.edu/meec/module06/WellDrilling.htm

PUMPING WELLS

• Creates cone of depression

• Lowers water table

Formation of a cone of depression in the water

table

Water stealing

subsidence

Artesian wells

• Flow to the surface naturally

• Under pressure• “sandwiched between

two impermeable layers

• Well must be below intake

Wikipedia’s version of artesian- is this correct?

GROUNDWATER POLLUTION

• SOURCES– Septic tanks– Landfills– Fertilizers/pesticides– Underground storage tanks (gas stations)

Septic tanks

landfills

Natural contaminates

• Calcium, magnesium creates “hard water’

• Will not suds up• Creates white film in

hot water pipes• Irons creates bad

taste

Hot springs and geysers

• Groundwater heated by magma reaches the surface

Steamboat, CO

OLD FAITHFUL

• With an error of 10 minutes, Old Faithful will erupt 65 minutes after an eruption lasting less than 2.5 minutes or 91 minutes after an eruption lasting more than 2.5 minutes.

• http://highered.mcgraw-hill.com/sites/0072402466/student_view0/chapter11/animations_and_movies.html#