The phytoplankton of the Cook Plant monthly minimal surveys during the preoperational years 1972, 1973, and 1974 / by John C. Ayers.

INTRODUCTION

The Donald C. Cook Nuclear Plant became operational during the winter of
1974-75, making the monthly minimum (short) surveys of 1974 the last of the
preoperational short surveys. Plant operation during 1975 has been intermittent and at different levels of power generation, but thermal plumes have
been produced, and surveys in 1975 and following years must be and are
classed as postoperational.
This report deals only with the monthly short surveys. It presents the
results obtained in 1974 and compares them to results obtained in 1972 and
1973.
Because 1974 was the last preoperational year, every effort has been
made to present the three years of preoperational phytoplankton results as
completely as possible and to indicate by example several parameters by which
it is envisioned that pre- and postoperational comparisons can be made.
Some of these parameters are unconventional and some may be only marginally defensible, but at this point in time it is considered that they represent aspects of the phytoplankton community in which changes could be detected
when and if plant operation brings them into existence.
During the field season of 1974, phytoplankton were collected monthly at
8 or 9 sampling stations in the vicinity of the Cook Plant and at two reference stations,one 7 miles north and one 7 miles south of the plant. Spring,
summer, and fall seasonal collections were made at 36 sampling stations in a
grid ranging 7 miles south and 7 miles north as well as 7 miles offshore. The
minimal monthly surveys were designed to give information on the temporal succession of species or groups (forms), while the large seasonal surveys were
designed to provide seasonal spatial distribution information and to be massive
enough to capture rare forms that might not be taken in the limited monthly
surveys, but which might be of value in assessing whether new forms were being
added to the population.
This paper addresses only the minimal monthly surveys; the large seasonal
surveys will be reported separately.

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