The EPA has 10 regional offices that assists is executing EPA programs for those states and territories within each region. California is part of Region 9, also known as the Pacific Southwest Office, located in San Francisco and includes Arizona, California, Hawaii, Nevada, Pacific Islands and 148 Tribal Nations.
The EPA offers summaries of well-known environmental laws. For each act, the EPA has written a summary and provides links to the text of the law, related regulations, and other useful information. These summaries are an excellent resource when starting research.