DOE OSTI2016
The regulatory requirements in the United States do not require any specific time frame for the duration of permanent marker systems to inform future generations of the presence of deep geologic nuclear waste repositories. The requirement is for markers to be 'as permanent as practicable'. For the Waste Isolation Pilot Plant in New Mexico, the U.S. Department of Energy chose a 10,000 year Passive Institutional Controls program goal. Passive Institutional Controls are to be designed prior to facility closure and implemented prior to the completion of the Active Institutional Controls program. Nuclear waste repositories across the world are actively developing marker and message systems, as required by their own regulations, for time frames either specified in those regulations or to be proposed to the regulator by the implementing organization. Time frames may be based upon the radioactive characteristics of the various isotopes being disposed of in the repository under consideration, or they may be based on some utility function that balances investment, practicability and risk. Scientifically, there are a number of time frames that make sense. However, an important determinant of effectiveness that has not been taken into consideration is the impact of the human connection, the receiver of the message. The major obstacle that the permanent marker systems need to overcome is the impact that humans will have over time. Historically, no monument has ever survived more than a few thousand years when humans come in contact with it. No matter what size of monument or topic the monument represents, humans have a history of destroying monuments beginning just a few generations after the monument's construction. The only way to ensure that a monument system can endure long time frames is to isolate it from humans. Eliminating contact with humans for whom the messages are meant defeats the very purpose of having an informative marker and message system. A more reasonable and historically supported time frame of 1,000 years would assure that no unreasonable cost would be incurred by current generations. Future generations could decide to continue maintaining the message, or not; and the likelihood of destruction of the markers by subsequent generations would be reduced since the knowledge of the markers and messages would have been transmitted within a more reasonable time frame over which language continuity, for example, would likely be manageable. Future preservation of the marker system and future human actions cannot be controlled, but the goal is to build a marker and message delivery system that reduces the likelihood of inadvertent future human disturbance of a deep geologic repository. This is the typical regulatory requirement on future information systems. Regulators who insist on an extremely long time frame for marker effectiveness should consider the historical realities of 'permanent' markers and monuments and propose a more reasonable time frame. Perhaps it would be more practicable to require 1,000 years for informing future generations and then allow them to determine what they wish to do to protect the future for another, perhaps similar, period of time. (authors)
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗