The California Environmental Protection Agency (CalEPA) identifies disadvantaged communities as those that are disproportionately burdened by multiple sources of pollution and with population characteristics that make them more sensitive to pollution. CalEPA used the CalEnviroScreen 3.0 to designate disadvantaged communities. The higher the score the higher the burden. There were a few communities identified in the San Mateo County.  Two census tracts in South San Francisco were scored 76-80% and 81-85%. San Bruno scored 76-80% and North Fair Oaks scored 81-85%. East Palo Alto also had two tracts one scoring 81-85% and the other 86-90%. Click here view the map in detail.