Techniques For Detecting Dredge Spoils

[oldmancoyote1]

I have seen very little about techniques for detecting spoil piles.  There is a nearby creek that was worked extensively with a dragline and a wash plant.  Lots of spoil piles there:  20 feet by 50 feet by 5 feet high with small boulders, a few cobbles, and no fines.

I have been tempted to work them, but I know squat about technique and equipment.  Any "Old Pros" out there who want to give advice?

Thanks

[Hard Prospector]

Get a shovel, hard tooth rake and VLF detector with good discrimination as there will be lots of iron trash in the dredge spoils. I used my F19 in such areas and found some good nuggets. Nuggets are likely to be the bigger variety (often specimens)  as mostly smaller screened  material was processed and sluiced. Persistence and patience is key....... Good luck

[Valens Legacy]

2 hours ago, Hard Prospector said:

Get a shovel, hard tooth rake and VLF detector with good discrimination as there will be lots of iron trash in the dredge spoils.

That is about the only way to find anything that was missed, and yes it is hard work as well as slow work.

Remember to rake the piles smooth to get to the gold on bottom that way you can find the majority of what was missed.

[oldmancoyote1]

I take it you tear down the spoil piles not just detect the entire piles themselves?

Thanks

[paradiceau]

Maybe Gerry M in Idaho will see this, and chime in as he has lots of experience with such piles.  In Alaska they knocked down and spread the piles with a D-8 or larger Cat.  The material was spread out on a relatively level area and there would be small windrows a few feet wide and maybe a foot or so tall between the spread material....  Perfect situation for a VLF machine, kind of like shooting ducks in a barrel.  (Ganes Creek Alaska, Clark-Wiltz operated the program, Dave drove the school bus.). Good people, good grub, great gold.

A problem with large piles is the nuggets migrate down when the rocks are disturbed so as Hard Prospector said it is best to spread the piles out if possible....  

HH

[BMc]

40 minutes ago, oldmancoyote1 said:

I take it you tear down the spoil piles not just detect the entire piles themselves?

Thanks

Some of these piles are extremely hard and compacted, making it difficult and discouraging pick and shovel type work. A large coil PI detector can often be used to good effect by going over as much of the pile as possible before having to break it up, or rake it down. Don't overlook the possibility that the dredge piles may have been used as a base for any roads that lead into the area. I recently saw a nice nugget found in the road leading to a creek that was adjacent to a dredge pile in WY.

Also, the dredge piles that were created on the day or days leading up to the War Production Board order L-208, in effect, shut down gold mining on December 7, 1942, and many of the newly created dredge piles were never worked as a result.

[Hard Prospector]

Very valid points but I must respectfully disagree on the PI suggestion as they still (pretty much) lack effective discrimination.  You see; just like the mine dumps at hard rock workings .....these dredge piles are full of iron trash as well. They were the "open air dumpsters" for the work site. Food cans, all forms of metalic trash, bottles even old worn out boots  was just thrown about the spoils piles or sometimes  even pitched into the dredge pond. 

BTW  if possible and legal,  getting a Bobcat or mini excavator into the site to spread material around would be a HUGE benefit.

[BMc]

I take your point HP. But, I have worked many dredge piles, that didn't have all that much old trash. Newer trash; bullets, especially, not much help using discrimination. I, personally have and still would start with a PI in certain types of piles just to see what it sounds like, then go from there. I've dug my share of Dozer shavings too. As they say in the Military: It all depends on the situation and the terrain . . .

[Hard Prospector]

I too have taken my PI machine to work dredge piles and after digging rusty cans and #2 shovel heads  at 3 plus feet was really wishing for effective discrimination.  Agreed.....every situation is different and your point is well taken.

[Valens Legacy]

11 hours ago, oldmancoyote1 said:

I take it you tear down the spoil piles not just detect the entire piles themselves?

My grandfather and I have used a small tractor with a bucket on the front end and scraped and smoothed down many piles. They were spread out so that they would be about 5 or 6 inches deep, and then we searched the area for gold. That was a lot of hard work but was worth it for the knowledge alone that I learned.

Some piles were small enough that we just used a pick, shovel, and rake. Those were the most hardest ones to do, but was also worth the time and trouble.

Good luck and good hunting.