Cook Plant preoperational studies 1970 / John C. Ayers ... [et al.].

Direct Measurements of Thermal Plume Duration. During the development
and testing of the bagged-water technique, bags of water were released at
plant outfall mouths and allowed to drift down the plume until ambient lake
temperature was reached. The bags were nearly filled with water and floated
low in the water; we could detect no evidence of wind pushing them out of the
plume.
The following summary gives the duration of drift from outfall mouth.to
points where the surrounding lake water was of ambient temperature.

Place &
Date
Bailly
20V170
Bailly
17X70
Michigan
City 17X70
Montague

Type of
plant
Generating
7~C excess
Generating
Generating
6~C excess

Load and flow
522,500 kw
150,000 gpm
temperature
153,600 kw
150,000 gpm
88,000 kw
70,000 gpm
temperature
7,500 gpm

Wind condition Drift duration
SSE 2-8 kn 30 min
28 min

SW 10-14 kn
SW 4-5 kn

lh 22 min
lh 04 min

Chemical

N 10-14 mph

35* min

* Bag was well out into ambient temperature by this time.
The short durations of the bag drifts were unexpected. They indicate
that, even in larger plumes, the duration of the excess heat is probably too
brief to trigger excess algal blooms.
C. THE ICE BARRIER AT THE COOK PLANT SITE
During the winters of 1969-70 and 1970-71 a commercial photographer has
been employed by Indiana and Michigan Electric Company to photograph lake ice
conditions in front of the Cook Plant site on approximately a weekly basis.

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