Scoring & Model
What is the CalEnviroScreen Model?
The CalEnviroScreen 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 7 Population Characteristics indicators.
How is CalEnviroScreen scored?
- Each census tract receives scores for as many of the 19 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.
- The Population Characteristics score for a census tract is the average of the percentiles for all the Sensitive Populations indicators and Socioeconomic Factors indicators for that census tract.
- The Pollution Burden score is the average of the percentile scores from Environmental Effects and Exposures indicators.
- The Environmental Effects indicator percentiles are divided in half because we consider environmental effects to make a smaller contribution to pollution burden than exposures do.
- To get the CalEnviroScreen score we multiply the Pollution Burden score by the Population Characteristics score.