The traffic proximity indicator is based on AADT count divided by distance in meters from the Census
block centroid. The proximity score is based on the traffic within a search radius of 500 meters (or
further if none is found in that radius). This distance was selected to be large enough to capture the
great majority of road segments (with traffic data) that could have a significant impact on the local
residents, balanced against the need to limit the scope due to computational constraints. The closest
traffic is given more weight, and the distant traffic is given less weight, through inverse distance
weighting. For example, traffic 500 meters away is given only one tenth as much weight as traffic 50
meters away.
EJ Screen RMP Facility Proximity
The RMP facility proximity is reflective of the total count of RMP facilities in each block group within 5
km of the average resident in a block group, divided by distance, calculated as the population-weighted
average of blocks in each block group
EJ Screen Lead Paint Exposure
The lead paint indicator is the percentage of occupied housing units built before 1960, calculated from
the U.S. Census Bureau’s ACS 5-year summary estimates on age of housing stock. EJScreen uses age of
housing stock as a surrogate for potential lead exposure as regulations banning lead-based residential
paint in 1978 led to the reduction and finally an end to the use of such paint in housing. The percentage
of older housing units is a proxy for potential exposure to lead paint and lead-containing dust that
accumulates indoors, in homes, or in other buildings where lead paint was used. EJScreen uses housing
units built before 1960.
Threatened and Endangered Species by County
This layer displays the number of threatened and endangered species in each county. Additional layers are available for the type of species, such as plants, animals, invertebrates, and more!
Weeks In Drought
This layer displays the percentage of weeks in any severity of drought for the years 2021-2023.
Drought Intensity, U.S. Drought Monitor
This layer displays areas that experienced dry or drought conditions in the last seven days. Data are retrieved as shapefiles from the U.S. Drought Monitor and are updated on a weekly basis. The affected areas are represented by polygons, which are classified according to drought intensity. Using quantitative and objective indicators, as well as local condition and impact reports, the U.S. Drought Monitor defines each drought intensity level as follows:
D0 – Abnormally Dry
D1 – Moderate Drought
D2 – Severe Drought
D3 – Extreme Drought
D4 – Exceptional Drought.
For more information about the data, please see the U.S. Drought Monitor Data Classification web page.
Real-time Air Quality Index (AQI) – Ozone and Particulate Matter
This US EPA feature layer is updated hourly and reflects the latest hour of air quality data received from each monitoring site that reports to AirNow. The concentration and AQI values are for Ozone and Particulate Matter (PM) only. Air quality index ranges from 0-5,000 with higher values indicating worse air quality.
Real-time Air Quality Index (AQI) – Ozone and Particulate Matter
This US EPA feature layer is updated hourly and reflects the latest hour of air quality data received from each monitoring site that reports to AirNow. The concentration and AQI values are for Ozone and Particulate Matter (PM) only. Air quality index ranges from 0-5,000 with higher values indicating worse air quality.
Weeks In Drought
This layer displays the percentage of weeks in any severity of drought for the years 2021-2023.
Threatened and Endangered Species by County
This layer displays the number of threatened and endangered species in each county. Additional layers are available for the type of species, such as plants, animals, invertebrates, and more!