The Human Interference Task Force was a team of engineers, anthropologists, nuclear physicists, behavioral scientists and others convened on behalf of the U.S. Department of Energy and Bechtel Corp. to find a way to reduce the likelihood of future humans unintentionally intruding on radioactive waste isolation systems. Specifically, the task force was to research the use of long-time warning messages to prevent future access to the planned, but stalled, deep geological nuclear repository project of Yucca Mountain.

PROBLEM

When atomic or fusion bombs are detonated in a war, or nuclear power plants are used in times of peace, an unnaturally high amount of radioactive waste is produced. This material will threaten human life and health for thousands of years. Consequently, nuclear technology necessitates the creation of a secure means of terminal storage for such materials for an unusually long time period.

However, there is no method available to continuously provide the necessary knowledge about the location of nuclear waste over thousands of years. The culture of earlier centuries becomes incomprehensible when it is not translated into new languages every few generations. National institutions do not exist longer than a few hundred years. Even religions are not older than a few millennia and do not typically hand down scientific knowledge.

Furthermore, the necessary length of storage is disputed among specialists. One work group in Germany concluded that nuclear waste must be separated from the biosphere up to one million years – about 30,000 human generations. Earlier assumptions were based on a period of 10,000 years, which seems to be too short given the half-life of certain radioactive isotopes (e.g. Plutonium-239 at 24,000 years).

The written historical tradition of humanity, in contrast, is only about 5,000 years. Warnings in cuneiform script could be interpreted by some specialists, but others, such as the writing of the Indus Valley civilization, are already illegible after a few thousand years.

REQUIREMENTS

Three parts of any communication about nuclear waste must be conveyed to posterity:

1. that it is a message at all
2. that dangerous material is stored in a given location
3. information about the type of dangerous substances

ANSWERS

To determine how to convey these three things, the "Zeitschrift für Semiotik" (Tübingen, Germany) issued a poll in 1982 and 1983 asking how a message might be communicated for a duration of 10,000 years. The poll asked the following question: "How would it be possible to inform our descendants for the next 10,000 years about the storage locations and dangers of radioactive waste?" leading to the following answers...