FEATURE ARTICLE
Managing the Environmental Legacy of U.S. Nuclear-Weapons Production
Although the waste from America's arms buildup will never be "cleaned up," human and environmental risks can be reduced and managed
Kevin Crowley, John F. Ahearne
Coming to Terms with "Cleanup"
The term "cleanup" poorly describes the current activities at DOE sites: Only a small portion of the approximately $7 billion in annual funding is actually used for contaminant removal and waste processing. Most of the budget is spent on site surveillance and maintenance. The cleanup program refers to these surveillance and maintenance costs as "mortgage costs."
In our view, these high mortgage costs are slowing work on high-risk problems that, if not addressed in a timely fashion, could lead to nasty future surprises. The slow progress in remediating the high-level tank wastes at Hanford and Savannah River is of particular concern. Many of the tanks are now well beyond their design lives and contain chemically complex and highly toxic waste, much of it in a liquid state. Some of the tanks are now leaking, and the number of "leakers" is likely to increase as the tanks age. Accidents, acts of God and terrorism are also concerns as long as the liquids remain in the tanks. Under current schedules, it will be several decades before all of this waste is recovered and immobilized, and some of the hardest work (such as retrieval of the "bottoms," rich in transuranic elements such as plutonium, from the single-containment tanks at Hanford) is being deferred until the later stages of the remediation effort.
The use of the term "cleanup" also suggests that the primary objective of the program is to remove waste and environmental contamination and return the sites to other productive uses. In fact, although some sites or parts of sites can be cleaned up and released for other uses, sometimes with few or no restrictions, the DOE has acknowledged that this will prove to be the exception rather than the rule and that parts of more than 100 sites are expected to be unacceptable for unrestricted release after cleanup. At many sites, and especially the large ones, contaminants are too widely dispersed in the environment to be recovered with current technologies. The stored wastes that exist at these sites can (and should) be processed to reduce volumes and stabilize the hazardous constituents, but after processing much of this waste will be reburied at the site. The hazards will be reduced or relocated, but not eliminated.
This fact is well recognized within the program, which defines cleanup as the completion of those actions necessary to meet agreed-upon standards and objectives, and not necessarily the removal of all waste and contamination. The expectations of regulators and local communities for achieving contaminant reduction and waste removal have been moderated since the cleanup agreements were signed as the technical difficulties and high costs of progress have become apparent. We sense, however, that expectations may still be higher than warranted in view of the difficult problems ahead, especially for the remediation of burial pits and trenches (such as Pit 9) and the retrieval and processing of high-level waste from the underground tanks, especially at the Hanford Site. Past success in site cleanup may not be a good harbinger of future prospects, because most of the difficult and costly problems have yet to be tackled.
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