Environmental Injustice and Cumulative Environmental Burdens in Neighborhoods Near Oil and Gas Development: Los Angeles County, California, and Beyond.

Residential proximity to oil and gas wells has been increasingly recognized to threaten the health and environmental quality of nearby communities. There are nearly 1 000 000 onshore oil and gas wells in operation and approximately 18 million US residents living within 1600 meters (one mile) of an active oil or gas well, placing them in the path of multiple hazards.[1] Much of the oil and gas activity is occurring in the state of California, where more than one million residents live within one kilometer of an active well.[1]

Living near active oil and gas wells has been associated with a range of health problems, such as increased adverse pregnancy outcomes, childhood cancer incidence, hospitalizations, asthma exacerbations, mental health issues, and mortality in the elderly.[2] Oil and gas development contributes to air pollution, noise, odors, water contamination, and ecological disruption.[2]

Several studies, often focusing on more rural areas, have shown that oil and gas wells and their associated hazards are not distributed equally across communities. This issue of AJPH presents a new environmental justice study that took a detailed look at Los Angeles County, the most populous county in the nation, which also has thousands of oil and gas wells. Chan et al. (p. 1182) found that oil and gas wells are disproportionately located in areas already burdened by multiple socio-environmental hazards and that have a higher proportion of Black residents.

The combination of numerous environmental hazards and social stressors has long been understood to contribute to heightened health risks and health disparities.[3] Spatial methods and policy tools for analyzing and visualizing the intersection of these hazards have advanced in recent years, with California leading the way with its California Environmental Justice Screening Tool (CalEnviroScreen). Chan et al. leveraged CalEnviroScreen to evaluate socio-environmental factors related to having an oil or gas well within one kilometer of a census block centroid. The results were striking: census blocks with the highest quintile of pollution burden had four times the odds of having an active or idle oil and gas well within one kilometer compared with the lowest quintile in multivariable models. After adjusting for other factors, a 10% increase in the number of Black residents was associated with a statistically significant 1.17-times-greater odds of having a nearby active or idle oil or gas well. The authors point out that the effect size for race was greater than that of other demographic factors, emphasizing the role of environmental racism.

These new results amplify findings observed in other states. In Texas, oil and gas wastewater disposal wells were more likely to be sited in communities of color,[4] and Hispanic populations were more likely to be exposed to flaring, a practice of burning excess gas yielding light at night, noise, and noxious odors.[5] In Ohio, oil and gas waste wells were disproportionately sited in areas of lower income.[6] Communities with high proportions of lower-income and elderly individuals in rural areas were found to be more vulnerable to groundwater pollution from unconventional oil and gas drilling in the Appalachian Basin.[7] A statewide analysis in California from 2005 to 2019 found that the proportion of Black, Hispanic and Latinx, and low-income people living within one kilometer of oil and gas wells was substantially higher compared with their representation statewide.[8] The Chan et al. study shows that in addition to these distributive injustices with respect to the location of oil and gas wells, communities near oil and gas wells are also facing concurrent exposure to other environmental hazards.

One notable feature of this study was that it illustrated how screening tools like CalEnviroScreen can and should be adapted to capture additional hazards critical to local communities. The authors emphasized that their analysis required acquisition of additional oil and gas well data from the California Geologic Energy Management Division because petroleum extraction sites are not yet included in the CalEnviroScreen tool. Consideration of oil and gas emissions wells in the tool or other neighborhood-level cumulative burden indices would enable spatial analyses that could help policymakers and community groups visualize or understand the impact of adding new wells or closing or phasing out existing wells.

Another important aspect of the study is the inclusion of idle wells—wells that have not been used for 24 consecutive months but are not properly sealed and therefore can be reactivated. Most health studies have focused on active wells. However, idle wells can release fugitive methane emissions, emit hazardous or odorous air pollutants such as volatile organic compounds and hydrogen sulfide, and contaminate groundwater.[9] Although they are required to be properly sealed when they are no longer intended for use, many oil and gas wells remain idle for years because of the high costs and low operator incentives for plugging. As such, the United States has more than two million orphaned, idle, or abandoned wells.[10],[11]

While the Chan et al. study and other studies help illuminate environmental injustices, they must be followed up with action to reduce disparities and protect public health. Two types of major policy protections are already being enacted in California: (1) setbacks, the allowable distance between an oil and gas well and a sensitive receptor such as homes, schools, and other places where people live, work, and play, and (2) restrictions or phaseouts, eliminating new or existing wells. In August 2022, California passed a landmark bill, Senate Bill 1137, which mandates a one-kilometer (3200-foot) setback between oil and gas wells and sensitive receptors, informed by the body of scientific evidence (https://bit.ly/47TGJY5). Los Angeles County also passed a motion to phase out oil drilling (https://bit.ly/47RHS2m). While setbacks offer critical public health protections to nearby communities, many states have not updated them to reflect the current science. In addition, setbacks are often considered for each industrial source separately and do not necessarily consider cumulative burden. Despite offering critical protections to overburdened communities, attempts to thwart these actions are underway. For example, Senate Bill 1137 has been suspended pending a statewide vote on a referendum supported by the oil and gas industry (https://bit.ly/3sBsyXO).

In their latest AJPH article, Chan et al. contribute further evidence of the environmental injustices and cumulative burdens facing fenceline communities in Los Angeles County. The results from this study, in conjunction with other epidemiological and environmental justice literature, provide strong support for policy actions such as setbacks and drilling restrictions, and efforts to delay public health protections place marginalized communities at risk.

The author reports no conflicts of interest.