Can groundwater sampling techniques used in monitoring wells influence methane concentrations and isotopes?
- 137 Downloads
Methane concentrations and isotopic composition in groundwater are the focus of a growing number of studies. However, concerns are often expressed regarding the integrity of samples, as methane is very volatile and may partially exsolve during sample lifting in the well and transfer to sampling containers. While issues concerning bottle-filling techniques have already been documented, this paper documents a comparison of methane concentration and isotopic composition obtained with three devices commonly used to retrieve water samples from dedicated observation wells. This work lies within the framework of a larger project carried out in the Saint-Édouard area (southern Québec, Canada), whose objective was to assess the risk to shallow groundwater quality related to potential shale gas exploitation. The selected sampling devices, which were tested on ten wells during three sampling campaigns, consist of an impeller pump, a bladder pump, and disposable sampling bags (HydraSleeve). The sampling bags were used both before and after pumping, to verify the appropriateness of a no-purge approach, compared to the low-flow approach involving pumping until stabilization of field physicochemical parameters. Results show that methane concentrations obtained with the selected sampling techniques are usually similar and that there is no systematic bias related to a specific technique. Nonetheless, concentrations can sometimes vary quite significantly (up to 3.5 times) for a given well and sampling event. Methane isotopic composition obtained with all sampling techniques is very similar, except in some cases where sampling bags were used before pumping (no-purge approach), in wells where multiple groundwater sources enter the borehole.
KeywordsGroundwater Sampling techniques Dissolved methane Shale gas Monitoring
The authors would like to thank Dr. Mathieu Duchesne of the GSC and Pr. Erwan Gloaguen of INRS for their advices and contribution related to the representation of data with Matlab. Our gratitude goes out to Mrs. Marianne Molgat, formerly of Talisman Energy, without whom this project would likely not have taken place. We would also like to deeply thank the Ministère du Développement durable, de l’Environnement et de la Lutte contre les Changements climatiques (MDDELCC), land and well owners that allowed work to be performed on their property, the Municipality of Saint-Édouard, the MRC de Lotbinière and the Ministère des Forêts, de la Faune et des Parcs du Québec. The authors also want to sincerely thank Nicolas Benoit and the anonymous reviewer for their review. This paper is GSC contribution # 20170288.
The authors would like to acknowledge the funding support from the Energy Sector (Eco-EII and PERD programs) and the Earth Science Sector (Environmental Geoscience Program) of Natural Resources Canada.
- Alperin, M. M., Reeburgh, W. S. and Whiticar, M. J. (1988). Carbon and hydrogen isotope fractionation resulting from anaerobic methane oxidation. Global Biogeochemical Cycles 2: 279-291.Google Scholar
- Bordeleau, G., Rivard, C., Lavoie, D., Lefebvre, R., Malet, X., & Ladevèze, P. (2018). Geochemistry of groundwater in the Saint-Édouard area, Quebec, Canada, and its influence on the distribution of methane in shallow aquifers. Applied Geochemistry. https://www.sciencedirect.com/science/article/pii/S0883292717303621.
- Coleman, N. P., McElreath, D. (2012) Short-term intra-well variability in methane concentrations from domestic well waters in northeastern Pennsylvania, AAPG Search and Discovery Article #90154©2012, AAPG Eastern Section Meeting: Stray Gas Incidence & Response Forum, Cleveland, Ohio, 24–26 July 2012, http://www.gwpc.org/sites/default/files/event-sessions/Coleman_Nancy.pdf.
- Devlin, J. F. (1987). Recommendations concerning materials and pumping systems used in the sampling of groundwater contaminated with volatile organics. Water Pollution Research Journal of Canada, 22(1), 65–72.Google Scholar
- EPA. (2013) Introduction to in situ bioremediation of groundwater, Office of Solid Wastes and Emergency response, EPA 542-R-13-018, 86 pages. https://nepis.epa.gov/Exe.Google Scholar
- Gorody, A. W., Baldwin, D., Scott, C. (2005) Dissolved methane in groundwater, San Juan Basin, La Plata County Colorado: analysis of data submitted in response to COGCC orders 112–156 & 112–157, November 2005 I.E. Conference, Houston, TX, 14 pages. http://ipec.utulsa.edu/Conf2005/Papers/Gorody_DISSOLVED_METHANE_IN_GROUNDWATER.pdf
- Hirsche, T., Mayer, B. (2009) A comprehensive literature review on the applicability of free and dissolved gas sampling for baseline water well testing. Report prepared for Alberta Environment, 47 pages, http://www.waterforlife.alberta.ca/documents/ApplicabilityFreeDissolvedGas-Mar2009.pdf
- Humez, P., Mayer, B., Nightingale, M., Ing, J., Becker, V., & Jones, D. (2015). An 8-year record of gas geochemistry and isotopic composition of methane during baseline sampling at a groundwater observation well in Alberta (Canada). Hydrogeology Journal, 24, 109–122. https://doi.org/10.1007/s10040-015-1319-1 CrossRefGoogle Scholar
- Interstate Technology & Regulatory Council (ITRC). (2007) Protocol for use of five passive samplers to sample for a variety of contaminants in groundwater, technical and regulatory guidance, 121 pages. http://www.itrcweb.org/GuidanceDocuments/DSP-5.pdf
- Kinnaman, F. S., Valentine, D. L. and Tyler, S. C. (2007). Carbon and hydrogen isotope fractionation associated with aerobic microbial oxidations of methane, ethane, propane and butane. Geochimica et Cosmochimica Acta 71: 271-283Google Scholar
- Ladevèze, P. (2017) Aquifères superficiels et ressources profondes : le rôle des failles et des réseaux de fractures, Ph.D. thesis, INRS-ETE, 220 pages.Google Scholar
- Ladevèze, P., Rivard, C., Lefebvre, R., Lavoie, D., Parent, M., Malet, X., Bordeleau, G., & Gosselin, J. S. (2016). Travaux de caractérisation hydrogéologique dans la plateforme sédimentaire du Saint-Laurent, région de Saint-Édouard-de-Lotbinière. Québec, Dossier public, 8036, 2016, 112 pages. https://doi.org/10.4095/297891 Google Scholar
- Lavoie, D., Rivard, C., Lefebvre, R., Séjourné, S., Thériault, R., Duchesne, M. J., Ahad, J. M. E., Wang, B., Benoit, N., & Lamontagne, C. (2014). The Utica shale and gas play in southern Quebec: geological and hydrogeological syntheses and methodological approaches to groundwater risk evaluation. International Journal of Coal Geology, 126, 77–91.CrossRefGoogle Scholar
- Lavoie, D., Pinet, N., Bordeleau, G., Ardakani, O.H., Ladevèze, P., Duchesne, M.J., Rivard, C., Mort, A., Brake, V. Sanei, H., Malet, X. (2016) The Upper Ordovician black shales of southern Quebec (Canada) and their significance for naturally occurring hydrocarbons in shallow groundwater. International Journal of Coal Geology, 158, 44–64.Google Scholar
- Lefebvre, R. (2017). Mechanisms leading to potential impacts of shale gas development on groundwater quality. WIREs Water, 4(1), 15 pages. https://doi.org/10.1002/wat2.1188
- McHugh, T. E., Kulkarni, P. R., Beckley, L. M., Newell, C. J., & Zumbro, M. (2015). Negative bias and increased variability in VOC concentrations using the HydraSleeve in monitoring wells. Ground Water Monitoring & Remediation. https://doi.org/10.1111/gwmr.12141
- Moritz, A., Helie, J. F., Pinti, D. L., Larocque, M., Barnetche, D., Retailleau, S., Lefebvre, R., & Gelinas, Y. (2015). Methane baseline concentrations and sources in shallow aquifers from the shale gas-prone region of the St. Lawrence Lowlands (Quebec, Canada). Environmental Science & Technology, 49, 4765−4771.CrossRefGoogle Scholar
- Muska, C.F., Colven, W.P., Jones, V.D., Scogin, J.T., Looney, B.B., Price, V. Jr. (1986) Field evaluation of ground water sampling devices for volatile organic compounds, In: Proceedings of the sixth national symposium and exposition on aquifer restoration and ground water monitoring, Columbus, Ohio, May 19–22.Google Scholar
- PA-DEP. (2012) Light hydrocarbons in aqueous samples via headspace and gas chromatography with flame ionization detection (GC/FID). PA Dept. of Environmental Protection, PA-DEP 3686, Rev. 1, 13 pages.Google Scholar
- Parker, L. V. (1994). The effects of groundwater sampling devices on water quality: a literature review. Ground Water Monitoring and Remediation, 14(2), 130–141. https://doi.org/10.1111/j.1745-6592.1994.tb00108.x CrossRefGoogle Scholar
- Puls, R.W., Barcelona, M.J. (1996) Low-flow (minimal drawdown) groundwater sampling procedures. EPA ground water issue, EPA/540/S-95/50, pp 12.Google Scholar
- Rivard, C., Bordeleau, G., Lavoie, D., Lefebvre, R., & Malet, X. (2017). Methane variations in groundwater over time. Hydrogeology Journal, online http://rdcu.be/yjMl
- Siegel, D., Smith, B., Perry, E., Bothun, R., Hollingsworth M. (2016). Dissolved methane in shallow groundwater of the Appalachian Basin: Results from the Chesapeake Energy predrilling geochemical database, Environmental Geosciences, 23(1): 1-47.Google Scholar