Date

Feb 5, 1968

Description

This not a record of the DoD-AEC briefing, except on one significant point: the scope of plutonium contamination: “38 % of the total plutonium burden has been located on the snow and ice around the site of the crash; 36% is within the [unclear words] corresponding to 100,000 counts per minutes as measured on the available instrumentation.” The area of black ice, some 20 acres, was the location of 95 percent of the plutonium contamination.

Assistant to the Secretary of Defense for Atomic Energy Carl Walske wanted the panel to consider areas where “action might be taken fairly promptly,” relating to three issues: the radiological situation, the cleanup, and the definition of an environmental monitoring program. A key consideration was that the area of black ice “will be completely gone by July and will begin to break up in April.” If a decision to remove the ice, snow, and debris was to be made, it would be necessary to so by 1 April: “time is of the essence.”

In the discussion of the radiological situation, the panelists, who included Wright Langham, believed it “very probably quite safe to allow the whole residual contamination on the ice to drop into the water and be dispersed as the ice melts.” Yet, in the discussion of cleanup issues, the panelists assumed that “a vigorous attempt to remove this main contamination would be well received by the Danes.” Moreover, the “Panel is not wholly charmed by calculations which might suggest permissible contamination of the sea water,” which would be the case if the plutonium-polluted ice melted into the bay.

As for biological-environmental monitoring, the Panelists agreed that before plutonium passed to larger animals and humans, it would be first observable in “detritus, algae, plankton, or a few specific animals such as the mussel.” The Panel suggested monitoring “emphasize these aspects rather than the extensive collection and examination of larger animals.”

Source

Department of Energy Open-Net

Document published in following posting(s):

The United States and Greenland: Episodes in Nuclear History, 1957-1968
Part II: The B-52 Crash and Its Impact

Oct 15, 2025

“The Chairman’s Account of the Preliminary View of the Safety Evaluation Panel for Thule Incident Following DoD-AEC Briefing, February 5, 1968,” with list of members of Panel, chaired by Herbert M. Parker, Battelle Memorial Institute, 5 February 1968, Secret