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Outline # Groundwater Hydrology               ESS 315/POE 313

I. Groundwater Supply and Hydrogeological Properties

Groundwater Supply
     -Global Hydrologic Cycle
                             e
     -groundwater recharg = precipitation - (runoff + ET) Think about what factors
     influence soil infiltration?
     -National Use
     -Washington State Use

Location and Distribution of Groundwater
      -zones of aeration, saturation and water table
      -aquifers vs aquicludes
      -springs

Hydrologic Properties
      -porosity: ratio of the volume of pore spaces in a rock or other solid to the
      material’s total volume.
      -specific retention:ratio of volume of water retained to total volume of rock/soil
      -specific yield: water yielding capacity (volume of water, after saturation, that can
      be drained by gravity to the total volume of the aquifer, as a percentage)
      drained by gravity to the total
      -permeability: measure of velocity of a fluid as it flows through a porous medium.
      (Darcy’s Law ) Q = K x I x A ; Q rate of flow, K hydraulic conductivity,
      I hydraulic gradient, A cross-sectional area

Groundwater Storage and Management
     -quantity of water stored in the basin and sustained yield
     -groundwater mining: amount of water withdrawn from aquifer exceeds aquifer’s
     sustained yield (e.g. High Plains aquifer)
     -saltwater intrusion:Ghyben-Herzberg lens

Water Quality
     -potable water standards:(U.S. public health service)
     -dissolved substances
     -pollutants

Conservation and A  lternative Sources
-conservation
-desalinization
-artifical recharge
US Water Use
Confined aquifer and potentiometric surface (height water will rise due to
hydrostatic pressure).
Groundwater overdraft in Florida. Implications for the survival of the
Everglades.
Solution weathering within karst landscapes results in very large conduits with
potential high hydraulic conductivity.
Overdraft can cause subsidence and collapse structures in karst
aquifers.
Sinkholes in karst landscapes.
Ground- and surface water contamination sources.
Subterrrestrial conduits within karst landscapes facilitate rapid migration of point
source contaminents.
Polluted surface waters can enter the groundwater system rapidly in karst
landscapes.

				
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posted:10/18/2012
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