Revisions to Method 301: Field Validation of Pollutant Measurement Methods From Various Waste Media

The Environmental Protection Agency (EPA) is publishing editorial and technical revisions to the EPA's Method 301 "Field Validation of Pollutant Measurement Methods from Various Waste Media" to correct and update the method. In addition, the EPA is clarifying the regulatory applicability of Method 301 as well as its suitability for use with other regulations. The revisions include ruggedness testing for validation of test methods intended for application at multiple sources, determination of the limit of detection for all method validations, incorporating procedures for determining the limit of detection, revising the sampling requirements for the method comparison procedure, adding storage and sampling procedures for sorbent sampling systems, and clarifying acceptable statistical results for candidate test methods. We are also clarifying the applicability of Method 301 to our regulations and adding equations to clarify calculation of the correction factor, standard deviation, estimated variance of a validated test method, standard deviation of differences, and t-statistic for all validation approaches. We have also made minor changes in response to public comments. Changes made to the Method 301 field validation protocol under this action apply only to methods submitted to the EPA for approval after the effective date of this final rule.