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Memorandum: Region 10 Guidance on Water Quality-Based Effluent Limits Set Below Analytical Detection/Quantitation Limits

Below is EPA Region 10's guidance for NPDES permitting, monitoring, and enforcement of water quality-based effluent limits set below the analytical detection/quantitation limit. This guidance is for effluent limits that are greater than zero but less than the minimum level (ML).

Guidance on Water Quality-Based Effluent Limits Set Below Analytical Detection/Quantitation Limits (pdf) (183.21 KB, April 25, 2005)
EPA Region 10 NPDES Permit Program.