"The Analysis of Hydraulic Fracturing Fluid Data from the FracFocus Chemical Registry 1.0." is a peer-reviewed analysis built on more than two years of data provided by organizations that manage FracFocus, the Ground Water Protection Council and the Interstate Oil and Gas Compact Commission. Operators disclosed information on individual oil and gas production wells hydraulically fractured between January 2011 and February 2013 and agency researchers then compiled a database from more than 39,000 disclosures. Researchers reviewed and analyzed this information to identify the chemicals and better understand the amounts of water used for hydraulic fracturing.