METHOD
INDEX FOR NITROGEN POLLUTION RISK GROUNDWATER / AQUIFER
•Aquifer Position:
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•Shallow/Karst ‑ means that the aquifer is a shallow  water table type with a depth of less than 100 feet  to the water table or that the local geology consists of  a shallow karst (sink hole and solution tube) structure extending to the ground surface or bottom of the root zone.
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•Intermediate ‑ means that the aquifer is a water table type (not confined), and the depth to the water table Is at least 100 feet but less than 1000 feet.
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• Deep or Confined ‑ means that the aquifer is very deep (1000 feet or more to water table) or that an aquiclude or aquitard is positioned between the aquifer and the ground surface such that the auifer is effectively Isolated from local percolation from the ground surface.
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