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Steve Royall NCPA CT-2 Discharge Characterization Page 4 of 6 January 22, 2007 Typical flow rates for these parameters were included in NCPA"s August 9, 2006 letter to the City. No specific analysis for these parameters was included in this analysis since there are no standard methods for analyzing the concentrations of these parameters. Discussion This section includes full discussion of all key results of the water quality characterization. In general, nearly all constituents in the NCPA effluent were either non-detect or were measured at lower concentrations than in the NCPA plant influent. Out of the full suite of analytes,only nineteen constituents were measured at higher concentrations in the effluent relative to the influent. Of these nineteen constituents, only four appeared to exhibit more than a two-fold increase in the effluent over influent. Of these four constituents, only two constituents appeared to exhibit more than a four-fold increase in the effluent over influent Three other constituents yielded results that suggest more than a two-fold increase between influent and effluent, but the data are not conclusive due to sample dilution or a non-detect measurement in one of the samples. For water quality parameters which were characterized as exhibiting less than a four-fold increase between influent and effluent, no mass loading is proven or implied by the slight increase in concentration of some of the monitored parameters. The measured increase in constituent concentrations, when apparent at all, are less on a percentage gain basis than the typical decrease in water volume through the NCPA process. The water discharge volume is typically 25% to 50% of the water accepted, yet no parameters demonstrated an increase by the 2x to 4x ratio that would be expected from the concentration cycle in effect at NCPA. The most likely explanation for any increase in constituent concentration less than 400% is evaporative concentration, not mass loading by NCPA. The results of analysis for constituents whose effluent concentrations were measured to be higher than their influent concentrations are summarized in Table 4, below.