Dissolved Methane Round Robin Case Study Regulations Without a Robust Analytical Method

Topics in Shale Gas
Oral Presentation

Prepared by R. Vitale, D. Gratson
Environmental Standards, 1140 Valley Forge Road, Valley Forge, Pennsylvania, 19482, United States


Contact Information: [email protected]; 610.935.5577


ABSTRACT

As the discovery and harvest of fossil fuels from shale formation has increased and provided valued domestic energy reserves, regulations and legal action have followed from the detection of light gases in ground water used for potable purposes. These actions have proceeded on the basis of an antiquated non-consensus/non-certified analytical procedure. Accordingly during 2014-2015 the Marcellus Shale Coalition Dissolved Methane Method Workgroup commissioned a round-robin study of dissolved light gas analysis. In this initial phase fourteen commercial and one government laboratory analyzed blind groundwater samples that had been collected at two locations. The study identified significant variation among the results, with dissolved methane values that varied from 7,400 to 35,000 g/L. The study showcased the need for a robust consensus analytical procedure and the need for additional work to identify the source of the variability. In 2016 the Marcellus Shale Coalition commissioned a second study, again using fifteen laboratories, who analyzed four reference standards that were submitted blind. The results of this second study will be presented starting with study design, reference standard preparation, data analysis, and the conclusion that calibration is the primary source of error. Techniques within the calibration process will be discussed relative to the source of error for analysis of dissolved methane.