INTRODUCTION
In its February 3, 1994, letter to Assistant Secretary of Energy Thomas P. Grumbly (National Research Council, 1994), reviewing the extent to which systems analysis was being used in the tank remediation program at the Hanford Reservation, Richland, WA, the Committee on Remediation of Buried and Tank Wastes (hereafter, committee) expressed concern that the containment-in-place option, in which the tank wastes would be left in place, stabilized, protected against migration, and monitored as necessary, had not been fully analyzed. Containment technology is no longer considered as a long-term option; it is being considered only as an interim measure while the tank contents are being removed.
The report that follows summarizes the results of the committee findings on this issue and illustrates the need for further analysis of this important option at Hanford. The containment-in-place approach is addressed herein from a technical viewpoint, but it is recognized that the approach may provide an option for resolving certain radioactive waste management and remediation problems that have other, nontechnical factors to consider.
Containment-in-place appears to be needed for the waste that has already leaked into the soil or might leak during sluicing of the tanks, and perhaps for the tanks themselves after the waste has been removed. Technologies are being developed for this purpose. The committee believes it would be useful to assess whether these technologies would provide adequate protection of public health and the environment if some waste were left in the tanks instead of being removed as currently planned.
Some aspects of the containment-in-place approach to the tank problem can be solved in the short term using existing technology, but there are also some long-term questions requiring much more analysis. The new containment-in-place technologies developed at Hanford for tank remediation will have the added value of finding application at many other remediation sites for both DOE and the private sector.
