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Risk-Screening Environmental Indicators (RSEI) Model

RSEI Data Dictionary: Maximum Contaminant Level (MCL) Data

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

MCLs are used to cap maximum concentrations in drinking water systems.

RSEI MCL Table (Spreadsheet)(21 K, December 2020)

RSEI MCL Table (Text Format)(15 K, December 2020)

MCL Data

Variable Description
CASNumber Chemical Abstracts Service Registry Number, which identifies a unique chemical. For chemical categories, CAS Numbers begin with “N”, followed by three digits.
CASStandard The Chemical Abstracts Service Registry Number identifies a unique chemical. The standard format contains three sets of numbers divided by hyphens (00-00-0).
ChemicalNumber Unique internal identifier (links to Chemical table).
Chemical Common name of the chemical.
MCL1988...MCL2018 MCL for each year an MCL was in effect.