Volcanoes

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What do you already know groundwater?
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http//earthsci.org/teacher/basicgeol/hydrolo/grou
ndwater-gradient.jpg
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Porosity vs. Permeability

• Porosity
• Measure of void space
• Permeability
• Measure of connectedness of void space
• Good Aquifers are porous permeable!

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http//groundwater.orst.edu/under/images/confinedb
.gif
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http//www.epa.gov/seahome/groundwater/images/draw
5.gif
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http//groundwater.orst.edu/protect/IMAGES/Wells.g
if
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An aquifer may be

• Isotropic
• intrinsic permeability is the same in all
  directions
• Anisotropic
• groundwater has a preferred direction of flow

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Q k A i

• Hydraulic Conductivity (k)
• may have a direction!
• Groundwater flow depends on hydraulic
  conductivity (including anisotropy), area, and
  hydraulic gradient.

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Groundwater Flow Nets

• Compile head data
• Contour water table potentiometric surface
• Draw flow lines
• Isotropic flow - to head
• Anisotropic more complicated

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http//www.chesapeakebay.net/images/groundwater.jp
g
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http//www.mmr.org/Community/guide/images/groundwa
ter-grndh2o-1.gif
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WaterWell Construction
http//www.agnr.umd.edu/users/wye/personel/Miller/
well.html
http//www.healthyvermonters.info/hp/waterquality/
drilledgif.shtml
http//www.bcgwa.org/waterwell/2bconstruction.html

http//mo.water.usgs.gov/current_studies/richards/
wetlands/images/wellcon.gif