Maybe you can't say it is a scam in a pure sense, but I can. It's a scam.
None of what you talk about is relevant if the gold is simply not there to begin with. They have never presented a report certifying the gold is there. They can paraphrase their "consultants" report all day long but without a signed, stamped report from a registered PE or RG, it is for naught. It is a scam.
Speaking of their consultants, it appears that Arrakis only does work for other scammer outfits (e.g. El Capitan). Guilt by association - sure! The elder Ager's consulting company (Nanotechnology) is most certainly a front set up just to receive some of the proceeds from SRCH's investors. SRCH is a scam.
240 pounds is not much, and wouldn't leave an obvious hole in the top of the slag pile. But yes, you bring up a good point - disturbing old mine waste (whether it be a waste dump, a tailings pile, or a pile of slag) would require a determination of applicability from the ADEQ Aquifer Protection Program. Do they have one? Do they need an APP? I doubt they do, because they are not really processing a significant amount of ore, and never will. It's a scam.
The management's ties to know scams is well documented (Google Charles Ager and Delgratia, etc. and see what you get). Bob Gunnison, one of the founders of the slag pile project, is a documented felon (securities fraud). He now works for Royal Mines and Minerals, another scam outfit, who claim to be able to extract gold from common fly ash (cinders left from burning coal). SRCH is a scam.
The board of directors pay themselves a massive salary every year. For what? It's a scam.
Did I mention SRCH is a scam?
