1. Groundwater aquifer / aquitard water table groundwater flow
groundwater contamination

2. Groundwater: aquifers
Any geologic unit through which water can move easily (i.e. it’s permeable) (= high permeability)
Porosity: how much water a geologic material can hold

3. Opposite of an aquifer? Aquitard / aquiclude
retards the flow of groundwater (it’s almost never really zero)

4. Groundwater: aquifers
What would be the properties (porosity/permeability) of conglomerate?
High porosity, high permeability

5. Groundwater: aquifers
What would be the properties (porosity/permeability) of unfractured granite?
Low porosity, low permeability

6. Groundwater: aquifers
Can you think of a rock/sediment with high porosity and low permeability?

7. Groundwater: aquifers
Can you think of a rock/sediment with low porosity and high permeability?

11. How is this possible? discharge=2000 ft3/s No tributaries here

12. Ground Water and Surface Water
These are almost always connected
If a stream contributes water to the aquifer it’s called a “losing stream”
If a stream receives water from the aquifer it’s called a “gaining stream”
Same stream can be both at different places or at different times

13. Pumping Animation
Go to animation at:

14. What is happening here?
In the low permeability case the water is pumped primarily from the area directly around the well, whereas with the higher permeability the water seems to be drawn from a more broad area surrounding the well "hole". Since permeability refers to the ability of a material to let a fluid move through it, the low permeability doesn't allow the water to venture far from the path of pressure change (the "hole" of the well).

15. What happens when this well is heavily pumped?

17. Groundwater Flow Groundwater velocity
Depends on permeability and hydraulic gradient (slope of water table)
Ranges from 100 m/day to mm/day
A good round number: 1 ft/day

21. What happens when a new well here is heavily pumped?

22. Flow direction can change