As the article notes - actual, effective warnings will act as powerful magnets for future archeologists, looters, thrill seekers, idiots, etc.
So either make the stuff extremely inaccessible, or disguise it as useless junk (and still pretty inaccessible).
Best idea I've seen for the former uses iron waste casks that looks like telephone-pole-sized arrows. Drop 'em into a deep-ocean subduction zone. The money and technology needed to fish them back out (6+ miles underwater, then ~200' of penetration into the ocean-floor sediments) will stop 99.99% of wannabe's before they can even get close. And the other 0.01% will understand in advance that there are far, far cheaper and easier ways to get their hands on iron casks and radioactive waste.
For the latter - find (or dig) a deep mine in a remote area, where the minerals available to mine are common, but the ore is much too poor for the mine to turn a profit. Put your waste in very bottom, then fake the mine being abandoned, and eventually suffering major cave-ins. (The cut-rate pillars left supporting the ceilings sagged and broke, or whatever.) Money-losing and abandoned mines are miserably common, and the cost and difficulty of digging out the bottom of a long-abandoned and -collapsed mine are very high.
As the article notes - actual, effective warnings will act as powerful magnets for future archeologists, looters, thrill seekers, idiots, etc.
So either make the stuff extremely inaccessible, or disguise it as useless junk (and still pretty inaccessible).
Best idea I've seen for the former uses iron waste casks that looks like telephone-pole-sized arrows. Drop 'em into a deep-ocean subduction zone. The money and technology needed to fish them back out (6+ miles underwater, then ~200' of penetration into the ocean-floor sediments) will stop 99.99% of wannabe's before they can even get close. And the other 0.01% will understand in advance that there are far, far cheaper and easier ways to get their hands on iron casks and radioactive waste.
For the latter - find (or dig) a deep mine in a remote area, where the minerals available to mine are common, but the ore is much too poor for the mine to turn a profit. Put your waste in very bottom, then fake the mine being abandoned, and eventually suffering major cave-ins. (The cut-rate pillars left supporting the ceilings sagged and broke, or whatever.) Money-losing and abandoned mines are miserably common, and the cost and difficulty of digging out the bottom of a long-abandoned and -collapsed mine are very high.