The California EPA comprises five departments and boards:

The Air Resources Board 

ARB regulations can be found here, under Title 13 Division 3 and Title 17 Division 3.

The Department of Pesticide Regulation

DPR regulations can be found here.

The Department of Toxic Substances Control

DTSC regulations can be found here.

The Office of Environmental Health Hazard Assessment

OEHHA does not create or enforce regulations. OEHHA's mission is to protect and enhance public health and the environment by scientific evaluation of risks posed by hazardous substances. OEHHA produces a list of substances known to cause cancer or reproductive toxicity. This list can be found here.

The State Water Resources Control Board 

SWRCB regulations can be found here.