Environmental Justice in Washington, DC

Graphics: Aileen Clarke
Data: EPA EJ Screen, 2021

Understanding the Data

The Environmental Justice (EJ) Index combines two demographic factors, low-income population and minority population, with a single environmental factor for each block group. The EJ Index uses percentiles to compare a block group to the rest of the nation. The percentile indicates what percent of the population has an equal or lower value, meaning less potential exposure to certain environmental risks.

For example, if a block group is in the 95% percentile of the Hazardous Waste Proximity Index, that means that 95% of the block groups in the US have equal or lower potential risk associated with Hazardous Waste.

Environmental Indicators

Lead Paint - Percent of housing units built pre-1960, as indicator of potential lead paint exposure, 2015-2019
Diesel Particulate Matter - Diesel particulate matter level in air, µg/m3, 2017
Air Toxics Cancer Risk - Lifetime cancer risk from inhalation of air toxics, 2017
Air Toxics Respiratory Hazard Index (HI) - Ratio of exposure concentration to health-based reference concentration, 2017
Traffic Proximity - Count of vehicles (AADT, avg. annual daily traffic) at major roads within 500 meters, divided by distance in meters, 2019
Wastewater Discharge - RSEI modeled toxic concentrations at stream segments within 500 meters, divided by distance in kilometers (km), 2021
Superfund Proximity - Count of proposed or listed NPL, aka superfund, sites within 5 km (or nearest one beyond 5 km), each divided by distance in kilometers, 2021
Risk Management Plan (RMP) Facility Proximity - Count of RMP (potential chemical accident management plan) facilities within 5 km (or nearest one beyond 5 km), each divided by distance in kilometers, 2021
Hazardous Waste Proximity - Count of hazardous waste facilities (TSDFs and LQGs) within 5 km (or nearest beyond 5 km), each divided by distance in kilometers, 2021
Ozone - Ozone summer seasonal avg. of daily maximum 8-hour concentration in air in parts per billion, 2018
Particulate Matter 2.5 - Particulate Matter 2.5, tiny particles or droplets that are 2.5 microns wide or less, levels in air, µg/m3 annual avg, 2018
Underground Storage Tanks - Count of LUSTs (Leaking Underground Storage Tanks), multiplied by a factor of 7.7 and the number of USTs (Underground Storage Tanks within a 1,500-foot buffered block group, 2021