In December 2016, EPA announced the review results for the Agency’s third Six-Year Review (called Six-Year Review 3). EPA analyzed compliance monitoring data for the Six-Year Review 3 using data provided by states/primacy agencies through the Information Collection Request (ICR) for Six-Year Review 3 covering January 2006 through December 2011.

Each zip file contains data for multiple contaminants and related information that can be unzipped into tab delimited text files. The number of records and associated systems in the data files and the size of the files range considerably from contaminant to contaminant, which may be attributed to many factors such as the applicability of monitoring requirements, the required sampling frequency and results from quality assurance/quality control (QA/QC) measures.

A detailed description of the data fields and their definitions, notes about the data, and instructions for downloading and importing datasets into software applications such as Excel can be found in the User Guide. Citation information for this dataset can be found in Data.gov's References section.