Home built drill for deep placer sampling

[Slatco]

My buddy has some deep placer ground (100ft) that we would like to test some day. Just wondering most economical way to do so. I see auger mounted nodwell drills, excavators or skid steers with rotary drivers but will they have the capacity to go deep? Is there something that can be built for this? Access is poor so am limited. Not a area of permafrost - any one got any ideas?

[chickenminer]

I have almost zero experience with drilling in a non-permafrost area. Going that deep to test a placer deposit would seem to be a real challenge. Drilling in unconsolidated material would certainly require casing to be driven the entire depth.
I'm thinking the most economical way would be to find one of the old churn drills, something like the Hillman airplane drill. They are slow compared to the new 'sonic' type drills but they get the job done.

[Slatco]

Thanks Dick. I have been mulling this over for years and have not really came up with any good solutions...

[Slatco]

https://www.westcoastplacer.com/drilling/

I guess these guys would be a option

[chickenminer]

Well it certainly looks like those guys know drilling in your area. I can't imagine it would be cheap but a lot cheaper in the long run then starting in at mining deep ground willy-nilly !!