The CCLEAN program was designed to protect ocean beneficial uses that were prioritized in surveys obtained from academic and regulatory agency scientists, recreational and business interests and local governments around Monterey Bay. Potential water quality stressors that could affect those beneficial uses were determined from published scientific articles and other reports, which enabled a program design to determine the sources, loads and effects of contaminants being discharged into the ocean.

Potential sources of pollutants included rivers, streams and municipal wastewater. Loads of persistent organic pollutants and nutrients were measured from rivers and wastewater, and concentrations of fecal indicator bacteria and nutrients were measured in coastal streams. Potential effects of the pollutants from these sources were determined by sampling mussel tissues, ocean waters 3.5 – 5.2 miles offshore, and sediment and biological communities along the 80-meter contour, where studies have shown fine sediment particles from land have accumulated over the past several thousand years.