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Drinking Water Testing

ORELAP Accredited Drinking Water Laboratories

EPA Method Detection Limit (MDL) Guidance for Drinking Water Labs

Some drinking water laboratories might have questions about how to implement the new MDL procedure.  EPA has provided some excellent guidance.  It's important to remember that the laboratory's approach must conform to both the federal regulations and the 2016 TNI Standard.  If there is ever a conflict, implement the most rigorous requirement.

EPA MDL Guidance for Drinking Water Laboratories


Drinking Water Reporting Rules

Oregon Administrative Rules require ORELAP accredited drinking water testing laboratories to report results above the maximum contaminant level (MCL) within a required timeframe.  Review the letter below for more information.

Drinking Water Reporting Requirements



Laboratories listed below can test public drinking water samples. This includes well water and tap water samples.