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Chapter Four of the SW-846 Compendium: Organic Analytes

The information contained in this chapter is provided by EPA as guidance to be used by the analyst and the regulated community in making judgments necessary to meet the data quality objectives (DQOs) or needs for the intended use of the data. This section highlights practices relevant to maintaining sample integrity and representativeness from the time of sampling until analysis is complete. This section is, however, applicable primarily to trace analyses. Some of these considerations may be less relevant for source level samples.

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