First, marking it in any fashion draws attention to it.
Second, anyone who can drill 1000m is high enough tech to figure out what it is. Nonissue.
Third, if they're not, but dig that deep anyway, we owe it to the gene pool to clean them out.
Fourth, this stuff has energy. We should be saving it for future use.
Fifth, how do the French and Japanese get rid of their nuclear waste? Surely someone has addressed this before.
Sixth, the danger really isn't that great http://muller.lbl.gov/TRessays/26-Witch-of-Yucca-Mountain.htm and making a big deal out of it just complicates things.
Seventh, I like the idea of shooting the scientists and asking 5 year olds to draw warning signs. Let's not overcomplicate it.
Eight, re: The "New Zealand is morally superior to all of you" poster. I'm sick of that crap about them not having a strategic military--they know the US, Australia, the UK and even Indonesia will save their asses if China gets frisky, and their "green" energy will work until the volcano powering it blows Auckland and all its smug inhabitants into screaming, blistered rubble. Remind me when I am World Dictator to evacuate the Maori, carpet bomb with ERRBs (Neutron bombs), then send the Maori back to civilize the survivors.
Nine, the floor is open. Thoughts?