Groundwater Quality and Hydraulic Fracturing: Current Understanding and Science Needs

Abstract

Hydraulic fracturing (fracking) is a process used for the stimulation and production of ultra-low permeability shale gas and tight oil resources. Fracking poses two main risks to groundwater quality: (1) stray gas migration and (2) potential contamination from chemical and fluid spills. Risk assessment is complicated by the lack of predrilling baseline measurements, limited access to well sites and industry data, the constant introduction of new chemical additives to frack fluids, and difficulties comparing data sets obtained by different sampling and analytical methods. Specific recommendations to reduce uncertainties and meet science needs for better assessment of groundwater risks include improving data-sharing among researchers, adopting standardized methodologies, collecting predrilling baseline data, installing dedicated monitoring wells, developing shale-specific environmental indicators, and providing greater access to field sites, samples, and industry data to the research community.

Prevention Techniques of Nitrate and Fluoride Pollution and Advances in Water Treatment

“…Industry in particular requires for most of their high amounts of water processes with the aggravating circumstance that after being used in such processes have many, without making any decontamination treatment, creating a serious environmental problem that leads to the onset of disease, odor production, unwillingness of highly toxic and carcinogenic chemical contaminants such as aromatic compounds, heavy metals, dyes, heavy compounds of the petrochemical industry, etc. [10].…”

“…Focusing on the use of wild-type catalysts as natural minerals or the use of waste materials of different industries such as coal, cement, power generation industries, among others. Giving solution to problems such as lower production costs of catalysts, re-use waste that can pollute and use these for the treatment of wastewater [10].…”

A Snapshot of the World's Groundwater Challenges

“…Energy production and storage, covering oil, gasoline, petroleum byproducts, volatile hydrocarbons, dense nonaqueous phase fluids, solvents, and coal fly ash, lead to groundwater pollution (88,89). Hydraulic fracturing of shale gas bearing formations using horizontal wells has grown rapidly in the past two decades, leading to the following concerns: (a) stray gas migration into shallow aquifers ( 90), (b) contamination by hydraulic fracturing fluids from leaks and spills in wastewater handling ( 90), (c) increased seismicity due to the reinjection of residual wastewater in deep geologic formations (91), and (d) development of biocide-resistant microbes that transform frack fluid additives to compounds toxic to humans and ecology (90). A perceived risk, that fracking chemicals may migrate from the 0.5-to 3-km depth of injection to upper shallow aquifers used for water supply, is not considered to be significant (90,91).…”

“…A perceived risk, that fracking chemicals may migrate from the 0.5-to 3-km depth of injection to upper shallow aquifers used for water supply, is not considered to be significant (90,91). The lack of baseline data on aquifer conditions is cited as a major limitation to the detection and attribution of the impacts (90)(91)(92). Wide variations in methane concentrations in groundwater are noted in areas with intensive gas production as well as in areas with limited activity.…”

Moving beyond forensic monitoring to understand and manage impacts of hydraulic fracturing for oil and gas development

“…These data could be engaged at the regional (or larger) scale to advance the reduction and management of environmental risk in unconventional hydrocarbon development. Issues of proprietary technology, economic competition, and legal liability make sharing of such data difficult (2, 10,19). Nonetheless, opportunities for government-industry-university partnering in research, such as has been achieved with the MSEEL, merit continuing effort.…”