Risk-Screening Environmental Indicators (RSEI) Model

RSEI Data Dictionary: Maximum Contaminant Level (MCL) Data

                            Tables in the RSEI Data Dictionary  
  Facility Chemical Submission Category Block Group Microdata Population Data  
  Offsite MCL Release Disaggregated Microdata Water Microdata Shapefiles  
  NAICS Media Elements Aggregated Microdata Census Crosswalks    

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

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.

Chemical

Common name(s) of the chemical.

MCL1988...MCL2016

MCL for each year an MCL was in effect.