Fig. 3: Distribution of exposure to wells by HOLC neighborhood grade.
From: Historic redlining and the siting of oil and gas wells in the United States
a Count of wells inside HOLC neighborhoods or within 100 m of the neighborhood boundary, stratified by HOLC grade. We considered exposure to all wells (left, including those without production dates), and wells drilled or operated before (middle) and after (right) appraisal occurred in each city. Note that approximately half of wells did not have production dates, and we were unable to include this in the before or after appraisal figures. b Density of wells per square km among HOLC neighborhoods with any exposure, stratified by grade. Each point represents the well density in one neighborhood. Similarly, we considered all wells (left) and wells drilled or operated before (middle) or after (right) appraisal occurred. The y-axis for panel b is restricted to 0–40 wells km−2 to better illustrate summary statistics, though several neighborhoods had densities above this range.
