Bacteria and phytoplankton of the seasonal surveys of 1972 and 1973 / John C. Ayers.

COOK PLANT PREOPERATIONAL STUDIES

A.2 STUDY OF FLOATING ALGAE AND BACTERIA
BACTERIA
Techniques
Coliform bacteria were determined by the nutrient pad method using
the Millipore Portable Water Analysis Kit and Field Monitors. The
Analysis Kit provides a pump and an incubator; the Field Monitors are
ready-to-use sterile nutrient pads and filters in incubating dishes and
come with ampouled nutrient media. M-Endo Broth was the nutrient medium
used.
Water samples ranging from 16 to 30 ml were pumped through the
Field Monitors. Water from 1-m depth was collected by Niskin bottle and
immediately drawn off into well-rinsed plastic bottles for refrigeration
until the Field Monitors could be prepared. Because of limited space in
the incubator, bacteria were not run at all stations.
Stations DC-1 and DC-5 were not sampled for bacteria in October.
DC-5 was accidently omitted; the station location of DC-1 was occupied
by construction equipment.
Results
The bacteria results are given in Table 2. As had been the case in
1971 (reported in Part XIX of our report series), the numbers of coliforms
exhibited wide variability in both space and time. Numbers have varied
from in the thousands per 100 ml in September 1971 to in the teens per
100 ml in July and October 1973, with low numbers being the general rule.
We are unable to escape the conclusion that the waters of the Cook Plant
region are occasionally "slugged" with water of damaged quality, but
cannot define the source(s) of that water.
There is no consistent evidence of any seasonal cycle of coliform

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