Sampling domestic/farm wells for baseline groundwater quality and fugitive gas

Autor: R. E. Jackson, Dru J. Heagle
Rok vydání: 2016
Předmět:
Zdroj: Hydrogeology Journal. 24:269-272
ISSN: 1435-0157
1431-2174
DOI: 10.1007/s10040-016-1369-z
Popis: It has become standard practice to monitor ‘domestic’ or ‘farm’ water wells to establish the baseline groundwater quality (GWQ), in particular for dissolved gases such as methane, in areas of actual or potential natural-gas development (e.g., Darrah et al. 2014). This is because of both regulatory requirements and the proximity of such water wells to areas of drilling operations that can lead to complaints of perceived deterioration of water quality. Domestic/farm wells are also used to study general GWQ, e.g., Hamilton et al. (2015), which poses some very difficult problems related to the integrity of such wells. This article reviews monitoring and quality assurance (QA) issues related to both objectives: (1) fugitive gas monitoring and (2) regional GWQ investigations. Domestic/farm water wells are not scientific instruments designed for sampling GWQ and they present numerous constraints that need to be understood and accounted for in such reporting. Leakage of ‘surface pollution’ (e.g., septic tank effluent, road de-icing salt and agricultural residues) into approximately one-third of domestic/farm wells in North America is well documented by many investigators (e.g., DeSimone 2009), resulting in a blended water-well sample with uncertain proportions that should not be identified as baseline groundwater quality. Given, firstly, the transient nature of natural gas emissions from oil and gas wells that may be recorded in domestic/farm wells as gas pulses (Gorody 2012; Dusseault and Jackson 2014) and, secondly, the uncertain integrity of domestic/farm wells described in the following, there is clearly a burden of proof on those sampling domestic/farm wells to demonstrate that the ‘pre-drill’ or regional GWQ data collected provide reliable information for use in both (1) dispute resolution in the natural-gas development or (2) establishing baseline GWQ data for groundwater-resources management. Baseline GWQ is defined here as that representing the starting point of monitoring such as Bpre-drilling^ (e.g., API 2009), and which typically includes some influences of human activities (Lee and Helsel 2005).
Databáze: OpenAIRE
Externí odkaz: