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Risk-Screening Environmental Indicators (RSEI) Model

RSEI Data Dictionary: Disaggregated 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  

These are the raw Microdata files that contain the most disaggregated data possible. For each 810 meter grid cell, the file contains scores, concentrations, and toxicity-weighted concentrations for each chemical release. There may be multiple records for any one grid cell. Note that if two releases for the same chemical (either from different facilities or one from a stack release and one from a fugitive release from the same facility) affect the same grid cell, there will be separate records for each grid release. 

Naming: These annual files have historically been named MicroXXXX_YYYY, where XXXX is the reporting year for the data freeze, and YYYY is the year of the data contained in the file. So Micro 2014_2010 is from the RY2014 RSEI update, and contains data for chemicals released in 2010. The new naming convention substitutes the version number for the version year, as in vXXX_micro_YYYY, where XXX is the version number and YYYY is the year of the data contained in the file; for example v234_micro_2014.csv.There is one annual file for the entire country, which is over 100 GB in size.   

Disaggregated Microdata Table

Field Number  Name Description
1 GridCode Identifies grid.  
  • 14=Conterminous US
  • 24=Alaska
  • 34=Hawaii
  • 44=Puerto Rico/Virgin Islands
  • 54=Guam/Marianas
  • 64=American Samoa
2 X X-coordinate of grid cell
3 Y Y-Coordinate of grid cell
4 ReleaseNumber Internal unique identifier for release (lookup in Release table)
5 ChemicalNumber Internal unique identifier of released chemical (lookup in Chemical table)
6 FacilityNumber Internal unique identifier of releasing facility
if media = 1 or 2, then lookup in Facility table  
if media = 6 or 750 or 754, then lookup in Offsite table
7 Media Code describing media into which chemical is released. 
(lookup in Media table)
8 Conc Concentration of chemical for release/media at grid cell (µg/m3).
9 ToxConc Concentration multiplied by inhalation toxicity weight
10 Score Risk-related score (surrogate dose * toxicity weight * population)
11 ScoreCancer Risk-related score (surrogate dose * toxicity weight * population) using only toxicity values for cancer effects
12 ScoreNonCancer Risk-related score (surrogate dose * toxicity weight * population) using only toxicity values for noncancer effects.
13 Pop Number of people in grid cell (may be interpolated)