Environmental indicators are quantitative measurements which can be used to evaluate overall environmental quality, trends in environmental quality over time, and the relative success of environmental regulatory programs in maintaining and improving the quality of the environment. Environmental indicators provide a mechanism for measuring regulatory program effectiveness more directly than the traditional measures such as the number of inspections, permits, and enforcement actions.

The constituent organizations of the California Environmental Protection Agency (Cal/EPA) have developed many different information systems to support programmatic activities. The purpose of this report is to utilize the information from those systems to define the environmental indicators which are currently available. Additionally, we hope to use this report to assist in the identification of relevant indicators for which we do not currently have adequate data. We also intend to ultimately move from environmental indicators to an environmental index or a set of indices which can simply and effectively communicate the overall status of California's environmental quality.

The Cal/EPA environmental indicators are presented in areas which parallel the structure of our constituent organizations: air, pesticides, hazardous and solid waste, and water. Additionally, a multi-media perspective is represented by California Toxic Release Inventory data. The indicators presented address only those environmental quality areas which are within the regulatory scope of authority of Cal/EPA.