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Risk-Screening Environmental Indicators (RSEI) Model

RSEI Data Dictionary: Census Crosswalks

                                                               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  

Each set of crosswalk files links the RSEI grid cell geography to a different US decennial census year. There is one crosswalk for each area and decennial Census year (1990, 2000, 2010). Crosswalk files are named by area (Alaska, Con(terminous) US, etc.).

The last three fields in each file contain percent values that can be used to adjust the block or cell contents when performing the crosswalk. PCT_B_C and PCT_C_B are area-weighted and can be used for metrics that do not involve population, such as concentration and toxicity-weighted concentration. PCT_PC_B is population weighted, and can be used to crosswalk fields that involve population, like score and pop.

Note that the "PCT_CP_B" field is not available for the territories (VI, PR, GU, AS, MP). The Northern Mariana Islands are in the Guam file and the Virgin Islands are in the Puerto Rico file. There are no crosswalks for Puerto Rico, the Virgin Islands, Mariana Islands, Guam, or American Samoa for 1990.  For these areas, RSEI uses 2000 block boundaries and scales each cell’s population by the overall ratio of 1990/2000 population for each area.

Census Crosswalk Table

Field Number

Name

Description

1

GridID

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 the cell address

3

Y

Y coordinate of the cell address

4

Block_ID00

US Census Block ID

5

UR

Internal

6

PCT_B_C

Percent of the Census block that is within the cell (Block to Cell)

7

PCT_C_B

Percent of the cell that is within the Census block (Cell to Block)

8

PCT_PC_B

Percent of the cell’s population that is within the Census block (Population-Cell to Block)