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

which to draw a reasonable conclusion about the probable effect of the Cook
Plant's future discharge plume upon the shore ice at and near the plant site.
In addition to the mode of formation of the shore ice and its structure at
maturity, it was necessary to obtain certain distance measures. The construction of the temporary harbor provided one of these: a means by which to scale
off distance on aerial photographs.
Personnel of Mr. Lawson's office kindly provided the dimensions of the
temporary harbor, of these, the 447 foot length (east-west) of the harbor's
south wall proved applicable.
Other needed distances and dimensions were provided by a map of the Cook
Plant ice made on 2 March 1971 by Dr. O'Hara and Jon Barnes. Distances in this
map were obtained by a combination of triangulation and pacing. Their map of
ice conditions on 2 March is given in Figure 17.
During Dr. O'Hara's overflight on 17 March 1971 he photographed the mature
ice structure at Cook when the four ice ridges and two lagoons were present without the complication of an outer ice field. In this photograph the distances out
to Ridges C and D, as mapped on 2 March, were used as checks in scaling distance
with the length of the south harbor wall as the measuring unit. The checks were
adequate, and the length of the south harbor wall was then used to locate the
two future outfalls of the plant. These, and identified parts of the ice structure, are shown in Figure 18.
In this figure the 1159'6" distance ofrshore to the outfalls (FSAR, vol. 1,
drawing 12-5961) has been scaled off and the outfall positions indicated and
labelled.
We see, and have evaluated, several facets in the question of whether the
Cook Plant's thermal plume will produce serious melting of the shore ice.
First, the mode of formation of the icefoot is such that storms from opposite

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