A Simple Test for Gases in Water
A proposed new ASTM International standard will provide a simplified way to test for dissolved gases, such as methane and ethane, in water. Environmental and testing laboratories will be able to use the proposed standard to ensure that drinking water is safe in areas in which hydraulic fracturing occurs.
Laboratories would use the proposed test — WK43267, Test Method for Measurement of Dissolved Gases Methane, Ethane, Ethylene and Propane by Static Headspace Sampling and Flame Ionization Detection (GC/FID) — to compare water from fracturing areas to water prepared with dissolved gases as a serial dilution. ASTM member Anne Jurek, senior applications chemist, EST Analytical, says that the proposed test method presents an “effective and standardized ” approach to testing for dissolved gases.
“The American Petroleum Institute recommends that drilling companies test surrounding drinking water reservoirs and wells before, during and after drilling to ensure that there are no residual effects from drilling,” says Jurek. “The proposed standard will aid this testing by normalizing dissolved gas analysis.”
According to Jurek, the results are a direct comparison of an unknown concentration of dissolved gases in a raw sample versus a saturated water sample diluted to a known concentration. “There is no back calculation, and the sample matrices are the same as the calibration standard matrices,” says Jurek.
Subcommittee D19.09 on Water-Hydraulic Fracturing Fluids is currently developing WK43267, which will include a multi-laboratory study. All interested parties are encouraged to join in the standards developing activities of ASTM International D19 on Water.