The U.S. Geological Survey sediment data quality assurance plan identifies and explains required quality assurance and suggested quality control practices. The approach is to subdivide the process for obtaining sediment data into 3 parts: (1) field, (2) office, and (3) laboratory operations. The report also summarizes recommended goals for each subcategory. The quality assurance and quality control practices are described by stating the minimum acceptable activities that a district should conduct. For example, the plan describes field calibration of thermometers and standards used to calibrate a thermometer. The plan also proposes corrective actions if the quality control procedures identify a problem. The plan describes the formal reports prepared by a district that describe the completeness of sediment data and presents an evaluation of data obtained by the quality assurance program. Also described in the plan are the external (non-district) reviews that are needed to examine district sediment operations for conformity with district quality assurance plans and national quality assurance programs.