An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Risk-Screening Environmental Indicators (RSEI) Model

RSEI Data Dictionary: Aggregated Microdata

                                                               Tables in the RSEI Data Dictionary
Facility NAICS Submission Disaggregated Microdata Census Crosswalks
EPA Program IDs (Reporters) Chemical Release Aggregated Microdata Population Data
Offsite MCL Elements Block Group Microdata Shapefiles
EPA Program IDs (Off-sites) Media Category Water Microdata  

Aggregated Microdata files use the same data as the disaggregated files, but sum the chemical releases over each grid cell. Because the values are summed, unweighted concentrations are not available (the sum of the concentrations of different chemicals would be meaningless).

Naming: These files are named as aggmicroXXXX_YYYY_GCZZ, where XXXX is the reporting year for the data freeze, YYYY is the year of the data contained in the file, and ZZ is the 2-digit grid code .  

Aggregated Microdata Table

Field Number Name Description
1 X X-coordinate of grid cell
2 Y Y-Coordinate of grid cell
3 NumberOfFacilities Number of facilities with releases affecting grid cell.
4 NumberOfReleases Number of individual releases affecting grid cell.
5 NumberOfChemicals Number of chemicals with nonzero concentrations for grid cell.
6 ToxConc Concentration multiplied by inhalation toxicity weight, summed over all chemicals impacting cell.
7 Score Risk-related score (surrogate dose * toxicity weight * population), summed over all chemicals impacting cell.
8 Pop Population of grid cell
9 ScoreCancer Risk-related score (surrogate dose * toxicity weight * population) using only toxicity values for cancer effects.
10 ScoreNonCancer Risk-related score (surrogate dose * toxicity weight * population) using only toxicity values for cancer effects.