Cook Plant preoperational studies, 1969 / John C. Ayers ... [et al.].

thanks are tendered.
On this day, with wind fluctuating between 37 and 40 mph, the waste heat
contributed by the Michigan City Generating Station was almost completely lost
within the harbor breakwalls. The data later indicated that there may have
been a leakage of about 0.9~C around the outer end of the east breakwall.
At the one station within the axis of the plume, as well as we could
determine, the temperature of the water ranged from 18.3~C at the surface to
17.2~ at one foot and stayed isothermal at 17.2~ from there to the bottom at
nine feet.
In about 2,200 feet from the outfall mouth to the outer end of the east
breakwall the plume had fallen from 21.1~ to 17.9~, a loss of 3.2~/4.2~ or 76%
of the excess heat (over 16.9~ ambient) added by the Michigan City Generating
Station. The area between the two outermost surface isotherms of the plume
(18~ to 17~) occupied more than half of the total demonstrable surface area of
the plume.
Michigan City, Indiana, Light Wind
During 28 June 1969, after the pas-sing of the major blow from the southwest,
we again surveyed the plume of the Michigan City Generating Station under quite
steady winds of 2 mph from the west-southwest. By renting a skiff and an outboard
motor from a local marina we were able to occupy six shallow-water stations in
and around the outfall channel mouth of the Michigan City plant. Stations in
greater depth were taken directly from the R/V MYSIS.
The day was clear, quiet, and hot and the movement of water current was from
the southwest primarily under the influence of the strong southwest wind of the
day before.
The trailing bowsprit thermistor was again the primary instrument for determining whether we were in or out of the plume, but all station data were taken

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