Vertical profiles of dye concentration were taken at three 

 points across each of the two quarry cuts on 25 August to 

 insure that complete mixing of the dye was occurring within 

 the quarry. Dye concentration readings varied less than 0.05 

 ppb by weight indicating complete mixing. 



2.5.2 Fluorescence Monitoring 



Dye concentrations were monitored using Turner Designs Model 

 10 and Turner Associates Model 111 fluorometers. Both 

 fluoro meters provide a relative measure of the quantity of 

 light emitted from a fluorescent solution. In principle, a 

 lamp within the fluoro meter emits light which is filtered and 

 allowed to strike the sample as it flow: continuously past 

 the light source. Any dye present in the solution will 

 fluoresce. The emitted light spectrum is passed through a 

 secondary filter to a sensor, compared to the source light 

 and the relative quantity of light is indicated by the 

 fluoro meter readout. 



The fluorescence of dye varies with sample temperature, 

 therefore, the water temperature in the sampling line was 

 monitored with a Yellow Springs Instrument Company Series 700 

 thermistor to enable data processors to correct recorded dye 

 concentrations for solution temperature. Both dye 

 concentration and temperature were continuously recorded 

 during all dye concentration surveys. 



Turner Model 111 fluorometers equipped with thermistors and 

 interfaced with Soltec two-pen strip chart recorders were 

 installed at both the quarry cut and at the Unit 1 discharge 

 well. The data from the instrument at the quarry cut was 

 used to determine the concentration of dye in the discliarge 

 water for later processing of the thermal plume dye 

 concentration data. Background fluorescence was also 



