3.0 Sample Collection and Preservation
3.1 See United States Environmental Protection Agency Great Lakes Analytical Contract Operation
Procedure for phytoplankton sample collection and preservation.
3.2 After the preserved phytoplankton samples arrive at the laboratory from the survey, an additional
10 mL of Formalin is added to each sample to enhance the storage life of the sample.
3.3 All sample containers and diatom slides must be properly labeled as follows:
a. Sample containers: Lake: Station, CRL and LAB Number; Sampling Date; Sample Type
(Integrated, B-1, B-2..etc.).
b. Diatom slides: Lake; Station, CRL and LAB Number.
Note: CRL numbers are assigned by GLNPO to all samples-collected in the field, LAB numbers
are assigned by the contractor in the laboratory, for internal use only, to facilitate the
sample log-in and identification procedure. Each sample has its own CRL Number that
corresponds to a specific LAB Number (see United States Environmental Protection
Agency Phytoplankton and Zooplankton Sample Log-in Standard Operating Procedure).