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Mapping Inequity

Wednesday, June 10, 2020

Siena Fouse

Intern, Research and Publications

Lovinia Reynolds

Lovinia Reynolds

Policy Analyst and Environmental Justice Coordinator

To address environmental inequity, we first need to understand where inequity exists geographically. Maps help model our reality and are a useful tool for locating and addressing environmental inequity. The power of maps in environmental justice was first revealed in 1987 in Toxic Wastes and Race in the United States, published by the Commission on Racial Justice. The report’s cover featured a map that validated community experiences of environmental burdens and identified where these burdens exist: in poor communities and communities of color. Since this original report, our mapping and environmental data technologies have radically improved. Digital mapping and publishing sped up the map-making process, and the development of Geographic Information Systems (GIS) has expanded the number of spatial analysis tools available. Data collection technologies, like low cost air sensor monitors, have become more accessible and accurate. These technologies are widely used to understand local environmental conditions and provide evidence to act on environmental inequity. 

In recognition of the manifold benefits of mapping technology, the U.S. Environmental Protection Agency (EPA) and other federal agencies have developed theirown maps and mapping tools to identify and spread information about environmental hazards. Such maps have been extremely useful for environmental justice advocates and decisionmakers. From citizen science groups to regulatory agencies, environmental data collectors are displaying their findings in conjunction with demographic data to identify and address disproportionate burdens of pollution. Some examples include EPA’s Community-Focused Exposure and Risk Screening Tool (C-FERST), which informed community residents on their risk of exposure to environmental health hazards, or the Toxic Release Inventory (TRI), which tracks release and prevention activities of toxic chemicals in the United States. TOXMAP, which was an environmental hazards map developed by the National Library of Medicine, generated a GIS that interactively displayed TRI data, data from EPA’s Superfund Program, as well as data from other United States and Canadian databases. And the Federal Emergency Management Agency (FEMA) uses Risk MAP to provide communities with information and tools to enhance their flood mitigation plans.NIH Toxmap screenshot

Perhaps the most widely used map by environmental justice advocates is EPA’s environmental justice screening and mapping tool, EJSCREEN. EJSCREEN went public in 2015 and uses 11 environmental indicators including particulate matter and ozone exposure along with six demographic indicators including race and income to assesses cumulative impact. EPA uses EJSCREEN as an analysis tool in their permitting, enforcement, compliance, and voluntary programs.

Recently, public maps are being used to assess environmental health and vulnerability to COVID-19. Due to the health effects of pollution exposure, including increased risk of cancer and respiratory illnesses, environmental hazards are a key risk factor for predicting the severity of coronavirus. Researchers have used maps like EPA’s EJSCREEN to demonstrate the correlation between coronavirus vulnerability and pollution burdens.

Despite their usefulness, environmental mapping tools can find themselves under threat. For example, per the guidance of the current administration, the National Library of Medicine removed TOXMAP in December 2019 from its website. The decision alarmed public health advocates as it made it more difficult for the public to identify possible environmental health hazards in their communities. Similarly, EPA’s climate change webpage, which included maps displaying regional impacts of climate change, was taken down in 2017. Other times the threat is a lack of resources or funding. For example, FEMA uses flood risk maps to discourage development in risky areas and determine which properties require flood insurance. However, recent studies show that these maps have fallen badly out-of-date and FEMA would need to invest billions of dollars to update existing maps and develop new maps for uncharted floodplains across the nation. And while maps offer a screening tool for identifying vulnerability, they are only as good as the data they display. For example, in areas where air quality monitors are poorly placed, an environmental health map may not perfectly correlate to the experience of communities on the ground. Experts note that maps should always be accompanied by ground-truthing and engagement.

Knowledge is power and the loss of any mapping tool represents a blow to residents’ ability to be aware of and subsequently act on potential health risks. Accurate and publicly accessible maps are crucial for informing residents of how spatial features like a power plant or toxic waste site threaten their health. Having an accessible visual of meaningful data can empower a community and validate their concerns.

While some federal environmental health maps have been removed and neglected, states are recognizing the value of environmental justice mapping tools and are designing maps of their own to help make decisions about and prioritize EJ issues. As highlighted in Charles Lee’s recent ELR article, A Game Changer in the Making: Lessons From States Advancing Environmental Justice Through Mapping and Cumulative Impact Strategies, these environmental health maps are developed with community-leadership, overlay demographic data, and draw a direct connection between public health and the environment. EJ community organizations have pushed government agencies to address cumulative impacts and have provided leadership on the methodology for identifying over-burdened areas. As Lee mentions, government agencies have struggled to incorporate the concept of disproportionate impact in decisionmaking, but by using EJ mapping tools to overlay demographic data and environmental burdens, they are better able to visualize vulnerability and risk factors of disproportionate exposure to pollution.

California stands out as a model for state level environmental health maps and their incorporation into environmental policy. CalEnviroScreen was deployed in 2013 by CalEPA’s Office of Environmental Health Hazard Assessment (OEHHA). There are 20 indicator data sets that fall into four groups: exposure, environmental effects, sensitive populations, and socioeconomic factors. These indicators are combined to produce a cumulative environmental health impact score for each census tract across the state. CalEnviroScreen was then used to identify which communities were eligible to receive rebates/funding under California S.B. 535, which mandates that 25% of proceeds from their Greenhouse Gas Reduction Fund go to disadvantaged communities. CalEnviroScreen has also been incorporated in the procedures of state program planning, municipality planning, CalEPA’s EJ Enforcement Task Force, and the California Air Resources Board’s Community Air Protection Program.

CalEnviroScreen’s success inspired other states to develop maps based on this methodology. University of Michigan graduate students supporting the Michigan Environmental Justice Coalition created a cumulative impacts map based on CalEnviroScreen’s scoring method and data from EJSCREEN. University of Maryland professors and students partnered with the National Center for Smarter Growth and the Environmental Health Network to develop the Maryland Environmental Justice Screen Tool (MD EJSCREEN), which also integrated aspects of CalEnviroScreen and EJSCREEN.

At the local level, maps such the San Francisco Department of Public Health’s Air Pollutant Exposure Zone Map are used to determine whether construction of a new development is taking place in areas of poor air quality. If so, enhanced ventilation must be installed to protect residents from the negative health effects of exposure to air pollution.

Over the next few years, we expect to see the expansion of statewide environmental health maps and their integration into environmental decisionmaking. New York’s Climate Leadership and Protection Act calls for state leaders to identify a methodology for identifying climate vulnerable communities. A New York version of California’s CalEnviroScreen is one potential option for this methodology.  

Environmental health maps are clearly useful for visualizing pollution, prioritizing the health of environmentally burdened communities, and catalyzing action. Governments, companies, and advocates alike have used them to steer decisionmaking and protect the health of the most vulnerable groups. As society grapples with the systemic racism embedded in the United States, EJ mapping provides one hopeful tool to address environmental inequities and to ensure healthy, vibrant, and sustainable communities for all.




All blog posts are the opinion of its author(s) and do not necessarily reflect the views of ELI the organization or its members.