Impaired Water Hazard Zones: Mapping Intersecting Environmental Health Vulnerabilities and Polluter Disproportionality

Abstract

This study advanced a rigorous spatial analysis of surface water-related environmental health vulnerabilities in the California Bay-Delta region, USA, from 2000 to 2006. It constructed a novel hazard indicator—“impaired water hazard zones’’—from regulatory estimates of extensive non-point-source (NPS) and point-source surface water pollution, per section 303(d) of the U.S. Clean Water Act. Bivariate and global logistic regression (GLR) analyses examined how established predictors of surface water health-hazard exposure vulnerability explain census block groups’ proximity to impaired water hazard zones in the Bay-Delta. GLR results indicate the spatial concentration of Black disadvantage, isolated Latinx disadvantage, low median housing values, proximate industrial water pollution levels, and proximity to the Chevron oil refinery—a disproportionate, “super emitter”, in the Bay-Delta—significantly predicted block group proximity to impaired water hazard zones. A geographically weighted logistic regression (GWLR) specification improved model fit and uncovered spatial heterogeneity in the predictors of block group proximity to impaired water hazard zones. The modal GWLR results in Oakland, California, show how major polluters beyond the Chevron refinery impair the local environment, and how isolated Latinx disadvantage was the lone positively significant population vulnerability factor. The article concludes with a discussion of its scholarly and practical implications.

Open Campus Policies: How Built, Food, Social, and Organizational Environments Matter for Oregon’s Public High School Students’ Health

“…where log(P/1 − P) was the natural log of the P probability of an Oregon public high school holding an open campus policy in 2017, α was the intercept, and β k X k is the sum of β coefficients for the k number of X independent variables [66,67].…”

Misrecognition in a Sustainability Capital: Race, Representation, and Transportation Survey Response Rates in the Portland Metropolitan Area

“…We used an established Bonferroni correction procedure in our assessment of the statistical significance of the Moran's I i results [72][73][74][75][76]. This procedure addresses concerns over abnormality, multiple comparisons, and spatial autocorrelation in the distribution of the standard normal variates (Z i ).…”

“…where v was the number of seemingly independent tests, r was the Moran's I for the OHAS household response rate or the prevalence of Latinx/Nonwhite householders across census tracts, and n was the number of tests [72][73][74][75][76]. We then divided the standard p-value of 0.05 by the number of seemingly independent tests to determine the FDR-corrected p-value for classifying the significance of the cluster/outlier results for the OHAS household response rate and the prevalence of Latinx/Nonwhite householders.…”

Racialized Structural Vulnerability: Neighborhood Racial Composition, Concentrated Disadvantage, and Fine Particulate Matter in California

“…Noteworthy among its results, the study found that residence in primarily White neighborhoods correlated with lower PM 2.5 exposures, while residence in primarily Hispanic neighborhoods correlated with higher PM 2.5 exposures. More recently, a nationwide, longitudinal, multi-level study found that, when compared to Whites, Blacks and Hispanics/Latinos (hereafter referred to with the gender-neutral term, “Latinxs” [14]) experienced significantly higher levels of exposure to PM 2.5 concentrations from 1990 to 2009 in their census block of residence, net of other individual- and metropolitan-level factors [15].…”