Interlaboratory Dissolved Light Gas Analysis Method Study
The dissolved methane studies that we have highlighted in prior issues of The Standard are coming to a critical final stage. In Phase 5, planned for early October, circa 11 laboratories will analyze blind samples for validation of the method. This final stage will include four analytes, methane, ethane, ethene, and propane in two certified reference materials (CRMs) that are being prepared by an ISO-accredited organization. In addition to the CRMs, four prepared standards will be analyzed in triplicate. Together, these standards will span critical analyte concentrations and provide precision and accuracy data. Measurement of dissolved light gases is critically important to oil and gas activities, as well as in monitored natural attenuation (MNA). MNA is often chosen as a cost-effective remediation approach under Resource Conservation and Recovery Act (RCRA) and Superfund projects. Prior phases have identified serious bias associated with the current procedures. The goal of this work has been to publish a validated method that can be used across the environmental and exploration laboratory communities. In preparation for a published method, we have approached the US EPA Waste Characterization Branch for possible incorporation in the SW-846 compendium of methods. We have also alerted the ASTM committees on our work and potential for collaboration.