Scoring & Model

What is the CalEnviroScreen Model?

 
The CalEnviroScreen 3.0 model is based on CalEPA’s definition of cumulative impacts.
  • The model is based on geography, specifically census tracts in California.
  • It presents information for the entire state.
  • The model is made up of 4 components – 2 Pollution Burden components and 2 Population Characteristics components.
  • Each component is made up of a set of indicators.
  • There are 12 Pollution Burden indicators and 8 Population Characteristics indicators.

Pollution burden is exposures and environmental effects. Population characteristics are sensitive populations and socioeconomic factors.

How is CalEnviroScreen scored?

  • Each census tract receives scores for as many of the 20 indicators as possible. Some census tracts will not have scores for every one of the indicators.
  • For each indicator, the scores are put in order from highest to lowest. This allows us to calculate a percentile for all areas that have a score.
  • An average of the indicators that make up a component (Exposures, Environmental Effects, Sensitive Populations, Socioeconomic Factors) is first calculated.
  • The Population Characteristics score for a census tract is the average Sensitive Populations and Socioeconomic Factors component for that census tract.
  • The Pollution Burden score is the average of Environmental Effects and Exposures components, where the Environmental Effects component is weighted one-half because we consider Environmental Effects to make a smaller contribution to Pollution Burden than Exposures do.

CalEnviroScreen 3.0 Indicators
  • To get the CalEnviroScreen score we multiply the Pollution Burden score by the Population Characteristics score.

Pollution burden indicators are multiplied by the population characteristic indicators to come up with the CalEnviroScreen score.