Steve,
Great question as for close to you, that can be a little bit of a challenge. We do have a large claim set in Venture County not that far from the Lytle Creek clams. and the claims group on the Cajon Summit area. After that you are looking towards the Barstow area to the north and the claims around Hemet to the south as the closest to you.
I've looked into a few claim areas closer but have not been able to find sustainable area that I wouldn't release within a couple of years when they easily become overworked.
I know that is not the answer you were looking for and I wish that I could offer more in that area. But if there isn't gold for the membership it doesn't work for the department.

There are a lot of canyons up in the hills east of Mission Viejo where gold has been found. Used to go up to Trabuco Creek and pan once in a while. There are a lot of areas where they found gold in Orange County and around Ortega Highway. A lot of literature is there but you have to look for it. Also, a lost gold mine in that area that is said to contain lode gold. Do some research as to the history of Orange County mining and you'll find something.
One of my old chemistry books said there is approximately 25-45 pounds of gold per cubic mile of ocean, depending on where in the world you look. But being CA., I'm sure they won't let you flood Newport to wait for evaporation. Good luck.

Thank you I appreciate it