Are you kidding? Pick a stream. Any stream. As long as the eco-nazis leave you alone. Be sure to check that you aren't on anyones claim. I was once for a whole summer, but they didn't care. They knew I wasn't going to get much with my hand sluice. The real gold was 17 feet down on the bedrock. Talking to them one day, they said that they took 17 ounces out of one pocket once. This was on the north fork of the American, just up from the bridge at the bottom of Mosquito Ridge Road. Since that man found that 5 lb. nugget in Butte county you might want to wander up that way.
I forgot where to find this info, but the" government" required all gold from the California gold rush to be sold to them. And they kept records of how much came out of which area/county. Where gold has been found before, it will be found there again.
You better check with fish and game about using a high banker on public land because generally speaking a high banker uses a motorized source for moving your water.Goodluck!
There used to be a helicopter service that would take you into some of the remote areas. One man that did this for two months came out with $30,000 in gold. This was back when gold was a few hundred an ounce. I have seen remote areas that would be hard for a helicopter to get in due to the steep and narrow canyons they were in. You would have to spend several days hiking into these areas. I spotted them from the road, about one to two thousand feet down a vertical mountain side. Happy Hunting!