Distinguish compliance and process work
A permit submission and an internal treatment investigation can have different method and reporting requirements. Identify which decision the samples need to support.
Specify parameters and fractions
Name analytes, units, reporting limits and any total or dissolved fractions. Include the required preparation and collection approach where stated by the program.
Plan grab or composite sampling
The collection approach must fit the parameter and applicable instructions. Define the locations, timing and preservation before sampling begins.
Keep method eligibility explicit
EPA explains that Clean Water Act requirements are governed by the permit and applicable approved-method provisions. An SW-846 method is not automatically an interchangeable discharge-compliance method.
Related testing & guidance
Technical & service references
Vanguard water-testing menuEPA: Clean Water Act method questionsEPA: Drinking-water analytical methodsSource review: November 8, 2026. The agreed method and project scope govern the testing.