Winter operations, 1970-1971 / John C. Ayers, Norbert W. O'Hara, William L. Yocum.

of thermal plumes on shore ice conditions are presented in only 16 slides to
supplement the results already presented in Part V (April 1970).
In Figure 1 the ice conditions at Big Rock Nuclear Station are shown. Shore
ice ridges reach up to, and into, the discharge channel. 18 February 1971.
Figure 2 shows that shore ice is present behind (inshore of) the submerged
outfall of the generating station at Traverse City. 18 February 1971.
The small (7500 gpm) submerged outfall of the DuPont Chemical Company at
Montague was recognized in the middle three-quarters distance of a long-distance
view (Figure 3) that contained sufficient landmarks for recognition. It makes a
small melt-hole between the basic shore ice and an outlying ice barrier. 18
February 1971.
The plume from the Consumers Power Campbell Plant at Port Sheldon, Michigan,
on 24 February 1971, is presented in Figure 4. This picture was taken far enough
away to encompass the whole effect of the plume and includes at least three fishermen in the slightly steaming plume. It shows a shore with melted-off shore ice,
but it also shows a shore with no visible evidences of erosion. We suggest that
the current from the discharge channel constitutes a wave-breaking force that
acts to protect these beaches.
The conditions of the outfall at Campbell Plant on 10 March (after snow and
a cold period) are shown from the shore in Figures 5, 6, and 7. These figures
constitute a south-to-north panorama of the Campbell plume. A heavy ridge of
ice lay, at this time, completely around the Campbell plume. Ten fishermen are
shown in the plume.
Figure 8 is of the discharge channel at the Palisades Plant of Consumers
Power Company, near South Haven, Michigan on 24 February 1971. The two inshore
ridges of the icefoot reach up to the discharge channel flume structures; the
frozen lagoon and outer barrier ice ridge are disrupted by the water-flow (with

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