shows the fifteen month mean percent effluent at all Safe Harbor stations 

 with 90 percent confidence limits. While the percentage of effluent was 

 not within the accuracy expected for laboratory bioassays, it was generally 

 within + 1 percent and was adequate for in situ bioassay work. 



The duration of the average percentage of effluent had to be included in 

 correlations of biological and physical data. An effluent exposure index 

 was devised by multiplying the average percent effluent times the number 

 of days that average was present (i.e., the number of days the plant was 

 operating during the period of exposure). 



To increase the validity of the hydrographic data, all stations were 

 sampled within two hours of taking the effluent and mixing water samples. 

 Generally, Stations 1 through 3 were sampled first followed by the 

 effluent samples, then the remaining Safe Harbor stations. Station 10, 

 the control station, was sampled last. Physical and chemical measurements 

 were taken on Mondays and Thursdays. 



Water samples were collected adjacent to each of the twenty biological 

 quadrats in a two-liter Plexiglas Van Dorn bottle manufactured by Hydro 

 Products (Model No. 120). Sub-samples, used for salinity and alkalinity 

 determinations, were decanted into polyethylene bottles having poly-seal 

 stoppers and analyzed the same day they were taken. Sub-samples for dis- 

 solved oxygen measurements were placed in standard 300 milliliter BOD bottles 

 with ground glass stoppers and immediately fixed with manganous sulfate, 

 alkaline iodide, and sulphamic acid. Sub-samples for copper analyses were 

 placed in aged polyethylene bottles and fixed for later analyses with two 

 milliliters of Baker analyzed hydrochloric acid. 



Temperature profiles were taken at each station by lowering a Yellow 

 Springs Instrument Company Model 437A telethermometer from the 

 surface to the bottom and recording temperatures to 0.1°C at two 

 feet (0.6m) intervals. The telethermometer was calibrated with two 

 Kahl Scientific Instrument Corporation thermometers and found accurate 

 to within + 0.1°C. 



Salinity was determined with a Bisset-Berman Hytech Model 6220 salinometer. 

 Oxygen determinations were made using a Each Chemical Company oxygen kit. 

 The powdered reagents for this kit were eminently practical, especially 

 when adverse weather conditions made handling the samples difficult. 

 Phenylarsene oxide supplied by Hach Chemical Company was used in the 

 laboratory titrations. 



Alkalinity was measured by a Hach Chemical Company alkalinity kit. 

 Alkalinity was obtained directly as equivalent CaCO in grains per gallon 

 from burette readings at the end of titration (1.0 grain/gallon - 17.118 

 mg/liter or 0.34205 milli-equivalents of hydrogen ion per liter). 



Copper analyses were made using the neocuperoine technique of Alexander 

 and Corcoran (1967) summarized in Appendix A. 



25 



