This layer displays the locations of the Environmental Protection Agency (EPA) Assessment, Cleanup and Redevelopment Exchange System (ACRES) sites. ACRES stores information reported by EPA Brownfields grant recipients on brownfields properties assessed or cleaned up with grant funding as well as information on Targeted Brownfields Assessments performed by EPA Regions. A brownfield site consists of land previously used for industrial purposes or some commercial uses. The land may be contaminated by low concentrations of hazardous waste or pollution, and has the potential to be reused once it is cleaned up. For more information, please visit the EPA Brownfields and Land Revitalization website or the ACRES Information web page.
Air Facility System Sites
This layer displays the locations of regulated facilities that discharge air pollutants in the United States. The Air Facility System (AFS) contains compliance and permit data for stationary sources of air pollution (such as electric power plants, steel mills, factories, and universities) regulated by EPA, state and local air pollution agencies. The information in AFS is used by the states to prepare State Implementation Plans (SIPs) and to track the compliance status of point sources with various regulatory programs under Clean Air Act. For more information, please visit the EPA Air Facility System web page.
Air Quality System Sites
This layer displays the locations of air quality monitoring stations in the United States. The Air Quality System (AQS) contains ambient air pollution data collected by EPA, state, Local, and tribal air pollution control agencies from thousands of monitoring stations. AQS also contains meteorological data, descriptive information about each monitoring station (including its geographic location and its operator), and data quality assurance/quality control information. For more information, please visit the EPA Air Quality System web page.
Air Quality – Fine Particulate Matter (PM2.5) by Census Tract, 2016
This layer displays the daily average concentration of fine particulate matter and the percentage of days with concentrations of fine particulate matter above the National Ambient Air Quality Standard (NAAQS) of 35.0 micrograms per cubic meter in 2016.
Air Quality – Ozone Levels (O3) by Census Tract, 2015
This layer displays the daily average concentration of ozone and the percentage of days with concentrations of ozone above the National Ambient Air Quality Standard (NAAQS) of 0.075 parts per million in 2015.
Air Toxics – Non-Cancer Risk by Census Tract
Layer displays the modeled non-cancer risk associated with air toxics exposure. A hazard index (HI) of 1 or lower means air toxics are unlikely to cause adverse noncancer health effects over a lifetime of exposure.
Air Toxics – Cancer Risk by Census Tract
Layer displays the modeled cancer risk associated with air toxics exposure. Figures represents the likelihood of hazardous exposure per 1 million population.
EJ Screen Air Toxic Cancer Risk
The air toxics cancer risk indicator is the estimated lifetime inhalation cancer risk from the analyzed
carcinogens in ambient outdoor air, as provided by the 2017 Air Toxics data Update. The value of the
indicator is persons per million lifetime. The data is reported at the Census tract level. Block group level
values are assigned by repeating each parent tract level value.
EJ Screen Diesel Particulate Matter
The Diesel PM indicator is the estimated concentration of Diesel PM as provided by the 2017 Air Toxics
update. The value of the indicator is in µg /m3
, and reported at the Census tract level. Block group level
values are assigned by repeating each parent tract level value.
EJ Screen PM 2.5
The PM 2.5 indicator is a measure of potential exposure to inhalable particles that are 2.5 micrometers or smaller. This is measured in terms of annual average concentration in air measured in micrograms per cubic meter. PM 2.5 information included in EJScreen highlights areas across the U.S. that are not meeting the national ambient air quality standard for PM 2.5. In other words, the levels of PM 2.5 present in these areas are deemed harmful to human health. The PM 2.5 indicator in EJScreen is a measure of potential exposure but not a measure of risk. The raw PM 2.5 data is compiled by census tract which is supplied for use in the tool by EPA’s OAQPS. For air toxics risk measures (as opposed to exposure) users can turn to EJScreen’s other three indicators: cancer risk, respiratory HI, and diesel PM.