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Analytical Methods for Drinking Water

Drinking Water Alternate Test Procedure Program

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Alternate Test Procedure Program Approach

When EPA sets a monitoring requirement for a contaminant, the Agency also establishes in the regulations at least one reference analytical method for analysis of the contaminant. Under EPA’s Drinking Water Alternate Test Procedure (ATP) Program, organizations can submit applications for:

  • The evaluation of modified versions of existing test methods
  • New test methods as equivalent alternatives to test methods included in the drinking water regulations

There is no tiering of methods or validation studies for drinking water ATPs. All test methods used to measure contaminants in drinking water must be approved for nationwide use in all matrices (ground water and surface water source waters). The EPA ATP programs will work together with the applicant to coordinate dual wastewater and drinking water applications.

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Application Requirements and Process

There are several requirements that must be met before an alternate test procedure or method can be evaluated by the Drinking Water ATP Program. The following documents discuss specific details regarding:

  • The ATP application process
  • Development of a validation study plan
  • Submission of the validation study plan final report
  • EPA review and approval processes

Protocol for the Evaluation of ATPs for Organic and Inorganic Analytes in Drinking Water (PDF)(27 pp, 271 K, About PDF)

Protocol for the Evaluation of ATPs for Analyzing Radioactive Contaminants in Drinking Water (PDF)(42 pp, 524 K, About PDF)

Microbiological ATP Protocol for Drinking Water, Ambient Water, Wastewater and Sewage Sludge Monitoring Methods (PDF)(94 pp, 830 K, About PDF)

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EPA Approval Process

If the applicant’s ATP meets the required performance criteria, EPA can approve the method in one of two ways:

  • Conventional notice-and-comment rulemaking
  • Expedited Method Approval

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