The O.P. was nice enough to PM me. And we had a little exchange about this. The form of "electrum", he said , was some sort of non-refined liquid . . That was slated to be refined into solid, yet stolen, and dumped into a lake, blah blah blah. Hence he fears that if the barrels broke down, then the material would be washed around and non-recoverable
And of course, it's got all the elements of a good treasure story. Ie.: the lone eye-witness thief, who's in jail for life, now 70-ish yrs. old, who's telling the story . And the company owner (from where this was stolen from 30 or 40 yrs. ago), who's confirming a theft, and agreeing to a split if recovered, etc....
Even with all those seeming "smoking guns" , I still think that such things are up to telephone game and "treasure fever" embellishing stories. Like for the seeming iron-clad component of a Co. owner, that could merely be subconscious steering. That if you approach some current owner of a company (who perhaps was not there 30 or 40 yrs. ago), and say "here's the facts", then sure: They might not argue , and you apply "confirmation bias" to anything they subsequently say.
Who knows ? Some treasure legends are true. But just saying that if we start to try to unpack a treasure legend for "true" vs "ghost story", then you ALWAYS find true components. Ie.: ALL treasure legends are based on real names, dates, events, etc... (yamashi-ta, the pearl ship, lost dutchman, oak island, etc...) . But if there's no treasure (ie.: the 1% of the story is just embellished ghost story speculation), THEN IT WON'T MATTER that the other 99% is "true".
But ... who knows ? I cast my skeptical "what if" and "how do you know" type questions to the fellow. And ... he never replied back to the last of our communication. I think we just left good enough alone, and there's no way to know for sure.