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EPA's Study of Hydraulic Fracturing and Its Potential Impact on Drinking Water Resources

QAPP for Multi-Laboratory Verification of Diethylene Glycol, Triethylene Glycol, Tetraethylene Glycol, 2-Butoxyethanol and 2-Methoxyethanol in Ground and Surface Waters by Liquid Chromatography/Tandem Mass Spectrometry

This QAPP describes the technical details and associated quality assurance and quality control procedures for the analytical method development research project.

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QAPP for Multi-Laboratory Verification of Diethylene Glycol, Triethylene Glycol, Tetraethylene Glycol, 2-Butoxyethanol and 2-Methoxyethanol in Ground and Surface Waters by Liquid Chromatography/Tandem Mass Spectrometry, Revised February 14, 2013 (PDF)(61 pp, 1 MB)