Management of Commercially Generated Radioactive Waste - U.S. ...

Summary
6.112
Major uncertainties, shortcomings, and advantages of the concept are summarized below:
* The concept is not compatible with the multi-barrier philosophy, relying only on a
potentially non-inert waste form and the geology.
* Performance assessment and siting technology for HLW injection are essentially
non-existent.
* Retrievability, technical conservatism, and adequate design margins do not appear
possible due to the diffuse nature of the emplaced material.
* The emplacement technology is considered to be essentially available.
6.1.6.4 Impacts of Construction and Operation (Preemplacement)
In some respects the environmental impacts of the well injection concepts are better
understood than the impacts from the other disposal alternatives. This is because of their
current use--deep well by the oil and gas industry to dispose of chemical waste and shale
grout injection by the Oak Ridge National Laboratory to dispose of remotely handled TRU
wastes. Potential use of well injection for disposing of long-lived or high-level radio-
active waste, however, has not been demonstrated.
Although quantitative estimates of environmental impacts of well injection have not been
made, it is expected that many of the impacts would be essentially the same for the two re-
ference concepts.
Health Impacts
Radiological Impacts. The radiological impacts from routine operations during most
phases of well injection disposal (e.g., reactor spent fuel storage, and intermediate spent
fuel storage) are expected to be the same as those for a mined geologic repository. However,
the extra operation to reprocess spent fuel from the once-through fuel cycle to produce a
liquid solution or grout could be expected to add to the radiological impacts. Quantitative
estimates of these impacts are not available at this time. Likewise, the radiological
impacts associated with the transportation of wastes are expected to be similar to those for
a mined geologic repository, with the exception of transporting HLW from the reprocessing
plant. Since, for the reference repositories, the injection facility is adjacent to the re-
processing plant, the need to transport HLW is eliminated, which thereby reduces the corres-
ponding radiological impact.
Unavoidable environmental effects of the well injection option would include operational
radiation doses to facility workers involved in injection or maintenance and repair. Design
and operational procedures would be directed to reducing doses to the lowest levels possible.
At the ORNL remotely handled TRU waste facility the radiation exposure per man per grout
injection has averaged 0.025 rem during injection operations and 0.188 rem during preinjec-
tion maintenance (ERDA 1977). However, the data are not sufficient to determine whether
these occupational exposures would be applicable to an HLW repository. Accident scenarios