A Comparison of the Methods Used for the Investigation of Dissolved Gas Concentrations

The analysis for dissolved gases in pre- and post-drill samplings of water wells in and around active drill sites has become an important and controversial topic. The results of such sampling and analysis can have a significant impact on water quality for the affected homeowner and a significant impact on costs of operation for the natural gas generator. With such high stakes for quality of life and reputations at hand, it would seem imperative that a very standardized and consistent method and analytical approach be utilized. Unfortunately, this is not the current practice. Various applications of RSK-175, a proposed ASTM method, and methods developed by several manufacturers are all used for pre-drill assessments and more significantly for stray gas investigations. Oftentimes the method, or variation of a given method, used by the enforcement agency’s lab will not return results consistent with the laboratory used by the generator’s lab. Yet each reporting lab is a certified lab for the application of dissolved gas analysis.

This paper will discuss several of the differences between the different methodologies and the variables within a given methodology that can impact the results generated from the analysis of a given sample location. Impact of sampling methodology will also be discussed along with some initiatives of the MSC around this issue.