Field and Laboratory Quality Assurance

Several quality-control measures were implemented in the field and at the Environmental Sampling Technologies Laboratory and the U.S. Geological Survey National Water Quality Laboratory to evaluate the integrity of the data being generated. Sample replicates and blank samples were collected in the field. Surrogate standards, isotope dilution standards, matrix spikes, reagent blank-water spikes, reagent blank-sand samples, polar organic chemical integrative sampler (POCIS) method blank samples, and POCIS method spikes were prepared in the laboratory. Quality-control measures used in 2014 were similar to those used in previous years of the study. Detailed descriptions and how the quality-control data are used can be found in Lee and [...]