Public and Private Environmental Laboratory Collaboration for Oil and Gas Regulatory and Industry Dissolved Gas Methodology From the State Lab’s Perspective

Public and Private Environmental/ Public Health Laboratory Partnerships
Oral Presentation

Prepared by M. McGarvey
PA DEP, PO Box 1467, Harrisburg, pa, 17105, United States


Contact Information: mmcgarvey@pa.gov; 717-346-8618

ABSTRACT

Analysis of methane and other light hydrocarbon gases in water has become an increasing interest in recent years due to the increase in shale gas drilling. Methane is not regulated in water by the EPA, there are no standardized approved methods available to guide the analysis techniques used by commercial and governmental laboratories. The EPA SOP known as RSK175 has been in use for many years along with several variations including purge & trap analysis and the use of aqueous calibration standards instead of the gaseous standards. In addition, an ASTM method is currently being reviewed for possible publication.

This presentation describes a series of collaborative studies involving multiple public and private participating laboratories with blind samples for dissolved methane analysis using various methods providing precision and accuracy problems. Analytical techniques demonstrated biased procedures by individual laboratories. The differences between US EPA SOP RKS175 and PADEP3686 will be presented. The information collected from phases of studies resulted in the preparation of a light gas standard operating procedure (SOP). Draft versions of the SOP were prepared and presented to participating laboratories for technical review and comment. The result was a final SOP used as the basis for a rigorous interlaboratory study.