A 1991 government panel that researched the problems of keeping people away from nuclear waste sites for ten millennia included an astronomer, linguist (language specialist), archaeologist, environmental designer, and materials scientist. They developed a number of possible designs for the sites that were meant to convey "a sense of danger, foreboding, and dread without the use of language or pictures," and explicitly not suggesting "shelter, protection, or nurture." The designs included huge spikes that seemed to come from underneath the ground and a "landscape of thorns." Irregular, nongeometrical forms are also considered to show that humans do not value the place or embody it with their ideals.

How to Say "Keep Out" for 10,000 Years

Nuclear waste sites like the recently approved Yucca Moun- tain remain potentially deadly for thousands of years, creat- ing an interesting practical dilemma: What is the best way to warn future...