NaNDA Parks and Pollution Proximity Explorer

What this map shows

The map displays park boundaries from the 2024 ParkServe database (Trust for Public Land) alongside EPA Superfund site locations. Parks are classified by their closest proximity to a Superfund site: direct overlap with a site, or overlap with a buffer extending 0.5, 1, 1.5, or 2 miles around a site. Parks with no Superfund site within two miles appear in the base parks layer only. Note that the 1.5-mile buffer is shown on this map only; the published dataset provides measures at 0.5, 1, and 2 miles.

Proximity measures indicate spatial overlap between parks and polluting sites, not actual pollution exposure. Actual exposure depends on pollutant type, dispersion patterns, wind, topography, and other factors. Superfund sites are polygon features representing contaminated areas, so measures reflect the area of overlap between park land and contaminated land.

Of the 151,366 parks in the ParkServe database, 2,442 contain land that overlaps directly with a Superfund site, and 26,886 (17.7%) contain land within two miles of one. Counts rise steadily with distance: 7,724 parks fall within a half mile of a Superfund site, 13,771 within one mile, and 20,193 within 1.5 miles. Overlap is not evenly distributed across the country. Colorado has the largest total park area overlapping Superfund sites, reflecting the large parks and large mining-related sites of the western US, while five states (Arkansas, Maine, Mississippi, North Dakota, and Wyoming) have no park land overlapping a Superfund site.

Get the data

The map visualizes the NaNDA Parks and Proximity to Polluting Sites dataset, which measures the number and area of parks in each U.S. census tract and ZIP Code Tabulation Area, along with the spatial proximity of parks to Toxics Release Inventory facilities and Superfund sites. The dataset includes TRI measures that are not displayed on this map.

Download the dataset and documentation from ICPSR

Accessibility

This map is built with ArcGIS Experience Builder, a third-party application. Esri’s ArcGIS Experience Builder Accessibility Conformance Report (February 2026) documents partial conformance with WCAG 2.2 Level AA. Keyboard-only testing in August 2026 found that the map’s left toolbar (Legend, Map Layers, Basemap Gallery) is reached with Tab and navigated with the arrow keys, and that layer controls inside each panel are fully keyboard operable. Two barriers remain: the map viewport itself receives keyboard focus without any visible focus indicator, and individual parks can only be selected with a mouse, so the per-park details in the map’s popups are not available to keyboard users.

Because the map cannot be made fully accessible, the same information is available in two other forms: the description above, and the complete dataset with documentation at ICPSR.

If you need this information in another format, email Nanda Admin for assistance.

How to cite

Map: Chemberlin, E., & Melendez, R. (2026). NaNDA parks and pollution proximity explorer [Web map application]. National Neighborhood Data Archive, Institute for Social Research, University of Michigan.

Data: Chemberlin, E., Melendez, R., Duchowny, K., Clarke, P., Noppert, G., & Gypin, L. (2026). National Neighborhood Data Archive (NaNDA): Parks and proximity to polluting sites by census tract and ZIP Code Tabulation Area (ZCTA), United States, 2024 [Data set]. Inter-university Consortium for Political and Social Research.

Funding

Research reported on this page was supported by the National Institute of Nursing Research and the National Institute on Minority Health and Health Disparities of the National Institutes of Health under award number U01NR020556. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.