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ATTACHMENT H:OPERATING DATA <br /> LEC-1 <br /> The injectate of the LEC-1 is different than that of the STIG-1 well because the two plants <br /> generate electricity through very different processes. The LEC-1 injectate primarily will be <br /> cooling tower blowdown water that has circulated through the system 5 to 7 times. This will <br /> result in an injectate that is more concentrated in most constituents than the STIG-1 injectate. <br /> Table H-2 summarizes the estimated LEC-1 injectate based on the worst-case scenario of <br /> 7 cycles of concentration,the Domengine Formation sample collected prior to any injection, <br /> and several representative samples from the STIG-1 injectate collected over a period <br /> of years. <br /> TABLE H-2 <br /> Summary of Water Quality Data from Samples Collected Periodically During Well Operation <br /> LEC-12 NCPA STIG-13 <br /> Domingme <br /> Parameter' Formation Projected 03/20/08 03/22/07 03/15/06 02/22/05 03/24/04 03/26/03 <br /> Na 3,200 1771 162 90 147 147 86 107 <br /> K 46 145.9 25.0 12.0 28.0 22.0 15.0 18.0 <br /> Ca 761 423.7 54.0 25.0 49.0 43.0 31.0 35.0 <br /> Mg 86 13.1 20.0 10.0 19.0 20.0 12.0 14.0 <br /> Cl 7,000 2384 148 66 114 132 87 98 <br /> Alkalinity 107.3 280.0 190.0 320.0 220.0 129.0 156.0 <br /> pH 7.85 7.50 7.80 7.70 7.70 7.60 7.30 6.50 <br /> SO4 8.0 869 93 19 69 76 49 43 <br /> NO3N 389.02 60.60 5.10 53.20 74.40 56.00 1.10 <br /> F 0.00 0.40 0.20 0.10 0.30 0.20 0.50 <br /> Si02 16.5 148.2 85.0 60.0 71.0 92.0 51.0 55.0 <br /> TDS 14,066 6256 760 450 760 780 527 522 <br /> Conductivity 17,780 12157 1260 646 1110 1110 880 906 <br /> 1 Units are in mg/L,except for pH (standard units)and conductivity(µmhos/cm). r quality is provided for the two <br /> plant injection wells.Quality of water injected into the backup well will be somewhere between these two, <br /> depending upon the plant providing the injection water. <br /> 2 Data from LEC AFC(2008) <br /> 3 Data from NCPA STIG-1 quarterly reports <br /> Geochemical evaluation of the compatibility of the LEC-1 injectate and the Domengine <br /> Formation water was conducted (Appendix 7). This evaluation indicated that no <br /> precipitates are expected to form. The one parameter of concern is nitrate.The proposed <br /> concentration of 253.7 mg/L could stimulate the growth of nitrogen-reducing bacteria in <br /> and around the LEC-1 well screen if organic carbon is also increased. However,because <br /> there is not analysis of organic carbon in the blowdown water,this cannot be predicted at <br /> this time. It is recommended that organic carbon be analyzed in the injectate water and <br /> re-assessed prior to routine injection. <br /> SAC/371322/082550024(ATTACHMENT-H.DOC) H-5 <br />