Guidelines Establishing Test Procedures for the Analysis of Oil and Grease and Non-Polar Material Under the Clean Water Act and Resource Conservation and Recovery Act; Final Rule

This action approves use of EPA Method 1664, Revision A: N- Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated N-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry (hereafter Method 1664) for use in EPA's Clean Water Act (CWA) programs. This action also deletes Method 9070, adds revised Method 9071B, and incorporates Method 1664 by reference for use in EPA's Resource Conservation and Recovery Act (RCRA) programs. Method 1664 is also approved for determination of non-polar material (NPM) as silica gel treated n-hexane extractable material (SGT-HEM) to support phaseout of use of CFC-113 for determination of NPM in EPA's CWA and RCRA programs. These actions are being taken as a part of EPA's effort to reduce dependency on use of chlorofluorocarbons (CFCs) to protect Earth's ozone layer and to meet the CFC phaseout agreed to in the Montreal Protocol and required by the Clean Air Act Amendments of 1990. Method 1664 uses normal hexane (n-hexane) as the extraction solvent in place of 1,1,2-trichloro-1,2,2-trifluoroethane (CFC-113; Freon-113), a Class 1 CFC.