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 This website is no longer updated and links to external websites and some internal pages may not work.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: Water 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  

This file contains the toxicity-weighted concentrations downstream of TRI discharges by stream segment. All years of data are contained in the file, which is named NHDMicroResults_conc_agg_XXXX, where XXXX is the reporting year of the data freeze.

Water Microdata

Field Number Name Description

1

ReleaseNumber

Internal unique identifier for release

(links to Release table).

2

Counter

Auto-increment count of COMIDs

3

ComID

"Common Identifier" of a flowline (sub-segment of a reach)- atomic unit of reach data that matches one-to-one to NHDPlus.

4

ReachCode

Code for reach

5

Conc

Concentration of chemical in flowline (mg/L)

6

Sequence

Number defining pathway of release (used to indicate branching).

7

TravelTime

Time(s) for release to go from top of flowline to bottom.

8

TravelLength

Distance (m) for release to go from top of flowline to bottom

9

Paths

Number of branches in stream path

10

FCode

Descriptor from NHDPlus for type of flowline (e.g., pipeline, stream)

11

ResCode

Internal code