Journal
ENVIRONMENTAL SCIENCE & TECHNOLOGY
Volume 56, Issue 14, Pages 10010-10019Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acs.est.2c00001
Keywords
groundwater; oil and gas; methane; brine; shale
Categories
Funding
- National Science Foundation [16-39150]
- Institutes of Energy
- College of Earth and Mineral Sciences at Penn State
Ask authors/readers for more resources
Unconventional oil and gas development can have a negative impact on water resources, especially in areas where it overlaps with traditional energy extraction. Through data analysis, this study found regional correlations between groundwater contamination and the proximity and density of unconventional oil and gas development. The research highlights the potential health risks posed by contamination exceeding environmental limits in densely developed areas.
Unconventional oil and gas development (UOGD) sometimes impacts water resources, including incidents of methane (CH4) migration from compromised wells and spills that degrade water with salts, organics, and metals. We hypothesized that contamination may be more common where UOGD overlaps with legacy coal, oil, and gas extraction. We tested this hypothesis on ~ 7000 groundwater analyses from the largest U.S. shale gas play (Marcellus), using data mining techniques to explore UOGD contamination frequency. Corroborating the hypothesis, we discovered small, statistically significant regional correlations between groundwater chloride concentrations ([Cl]) and UOGD proximity and density where legacy extraction was extremely dense (southwestern Pennsylvania (SWPA)) but no such correlations where it was minimal (northeastern Pennsylvania). On the other hand, legacy extraction of shallow gas in SWPA may have lessened today's gas leakage, as no regional correlation was detected for [CH4] in SWPA. We identify hotspots where [Cl] and [CH4] increase by 3.6 and 3.0 mg/L, respectively, per UOG well drilled in SWPA. If the [Cl] correlations document contamination via brines leaked from wellbores, impoundments, or spills, we calculate that thallium concentrations could exceed EPA limits in the most densely developed hotspots, thus posing a potential human health risk.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available