How did the current concepts about “data quality” develop?
Waste programs depend on analytical methods to detect and quantify low or trace contaminant concentrations in very complex matrices, such as soils, sediments, waste materials, and natural waters. No such technologies existed early in EPA s history. They were developed and standardized in the 1970s and 1980s. It was expected then that site data would be more reliable if analytical procedures were more sophisticated, and their operation was standardized. This concept became codified through EPA guidance, state regulations, and lab certification programs that laid down strict requirements for which analytical methods were acceptable and how they were implemented. “Data quality” was defined in terms of these strict guidelines. “Definitive” and “screening” levels of data quality were defined according to the rigor of the analytical method and associated QC. Although this first-generation data quality model made sense at the time, practitioners discovered that it had fatal flaws. One critica