EXAMINING ASSOCIATIONS BETWEEN SOCIODEMOGRAPHIC CHARACTERISTICS AND GROUNDWATER VULNERABILITY TO CONTAMINATION FROM UNCONVENTIONAL OIL AND GAS DEVELOPMENT

The expansion of unconventional oil and gas development (UOGD) in the early 2000’s has generated some socioeconomic benefits and enabled the United States to become a net energy exporter in recent years. Nevertheless, concerns about the water-intensive industry’s potential risks to the environment and public health persist in many UOGD-hosting rural communities where residents use groundwater for drinking and other daily needs. In this work, we characterize the risks posed by UOGD on drinking water in the northern Appalachian Basin using an ensemble of physically based models to quantify groundwater vulnerability to contamination. We then assess if groundwater users in marginalized communities are disproportionately exposed to contamination risks by analyzing associations between groundwater vulnerability and census tract level sociodemographic characteristics using hierarchical Bayesian spatial generalized linear mixed models. Groundwater vulnerability was elevated in tracts with larger proportions of residents aged 65 and older, with larger populations below poverty, and lower income per capita. These associations suggest social disparities in the distribution of UOGD contamination risks. Elevated groundwater contamination risk in communities with more elderly populations poses a public health concern given their underlying physiological susceptibility to environmental stressors, while populations with lower socioeconomic status may have reduced capacity to mitigate exposures, for instance via access to alternative drinking water sources. Additional research is needed to investigate if this observed distributive environmental injustice in groundwater vulnerability translates to differences in chemical exposure and negative public health outcomes.