Here are some shots of the type of areas I have found Good gold. That is, about 10 specks and flakes per bucket.

I worked this hole, under the biggest rocks, for 3 days.
Yielded about a gram. I was 20 feet from the sluice and was just above the water table.
One flake was about a 1/4". Some of the rocks were 6' in dia. and bigger.
They were buried in the river bank.
I tried to find up stream boulders and dig behind them, but gold stops in front as well as behind large rocks.

This is the north end of Heaton Flats. I have mined up and down the San Gabriel East Fork River and I always seem to end up back here and always find good gold.
My last good spot was in the older river bank 30' above the river here. That was in Sept.2012.
I was working a dry hole that is above the river trail. 20 specks per bucket. Where I mine no gas powered gear is allowed.
Hauling buckets 40' or more back and forth to the sluice in the river is a lot of work.
I'm working on a solar powered recirculator sluice.
I have a simple rig that uses a EZ-Sluice, 5 watt solar panel and a 12v battery pack.
The right DCV water pump is hard to find. I'm looking for a pump that puts out 500 gph
I need to hike it in about a mile from where I park and cross the river once.
I think the real adventure of mining is the wonderful challenges that mining presents as you want to do better and better.
I have made it a personal challenge to design and build my own gear when I could.