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Superfund CLP National Functional Guidelines for Data Review

Prior to the 1990s, each EPA region had its own individual guidance for determining the usability of analytical data. Many problems occurred when data was not consistently reviewed. ASB established a work group and worked with representatives of all EPA regions to develop the first and most widely used centralized, consistent National Functional Guidelines (NFGs) that established baseline guidance and solved problems with analytical data.

The NFGs assist data reviewers in evaluating whether the analytical data meet quality control criteria, as well as the usability and extent of bias of any data not meeting these criteria. The NFGs also provide definitive guidance in areas such as blanks, calibration standards, and instrument performance checks and aid the reviewers in making subjective judgements regarding the use of data that is affected by site conditions and do not meet SOW-specific requirements.