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Polluted Runoff: Nonpoint Source (NPS) Pollution

Spreadsheet Tool for Estimating Pollutant Loads ( STEPL) and Region 5 model reference documents

The Spreadsheet Tool for Estimating Pollutant Load (STEPL) employs simple algorithms to calculate:
  • nutrient and sediment loads from different land uses, and
  • the load reductions that would result from the implementation of various best management practices (BMPs).

Additional  Documents to supplement Materials on STEPL  and REgion 5 model pages :

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