- Participate | History | Sponsors | Waivers/Safety Photo Gallery | What's so bad about marine debris California Coastal Cleanup Day is the premier volunteer event focused on the marine environment in the country. Each year, more than 40, 000 volunteers turn out to over 400 cleanup sites statewide to conduct what has been hailed by the Guinness Book of Records as the largest garbage collection ...www.coastal.ca.gov/web/publiced/ccd/ccd.html