Household-Level Population Estimates and Building Setbacks near Underground Natural Gas Storage Wells in PA, OH, NY, WV, MI, and CA

Abstract

Health impacts have been reported in people living near oil and gas operations (e.g., asthma exacerbation). Towards assessing these risks, studies quantifying proximate populations generally assume an even spatial distribution of population within an administrative unit (e.g., census block). These proportion population allocation (PPA) methods can be improved by excluding non-residential land use areas (i.e. dasymetric mapping), but are still too imprecise to obtain reliable estimates of population densities at small spatial scales (e.g., 50m2). Here we present ABODE (Allocation By Occupied Domicile Estimation), a novel household-level population estimation method that combines geospatial addresses, building footprints, and U.S. Census data. We assess ABODE and PPA methods by comparing population estimates within 200m of active underground natural gas storage (UGS) wells (n = 8,963) in six U.S. states. Overall, ABODE predicts slightly higher population estimates compared to PPA (48,126 vs. 43,052); however estimation bias varied by state and by individual well. ABODE captured higher populations within 200m of UGS wells in OH, WV, and PA with increases of 6, 54, and 66% compared to the PPA method, respectively. Conversely, the ABODE method captures fewer populations in NY, MI, and CA, with decreases of 4, 7, and 26%, respectively. By explicitly identifying households near active UGS wells in the six states, we also quantify well-to-building relationships and compare to state surface setback regulations where they exist. An estimated 9.4% (840) of UGS wells across the six states have at least one building within a regulated setback distance. This results in 2,769 households, or an estimated 4,816 people, living within these states’ respective setbacks (e.g., 100 - 625ft.). The spatially-resolved nature of the ABODE method provides a clear advancement from previous proximity-based methods towards understanding present and future land-use conflicts.