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monitored weekly for flow and pH until a new NPDES permit went into <br />effect on July 1, 2010. They are now monitored monthly. All five NPDES <br />sites are monitored monthly for NPDES parameters and field parameters. <br />Samples obtained at the stream sites are analyzed for one of the new <br />surface water parameter lists during spring runoff and summer baseflow. <br />Spring sites are monitored in the spring season. The current surface <br />water and spring monitoring program is presented in Table 15-9 of the <br />Yoast Mine PAP. <br />All surface water data collected during this reporting period are <br />provided in Appendix D. Data for each site begins with a flow hydrograph <br />of all historic data (plus an annual hydrograph for NPDES sites), <br />followed by a listing of individual water quality and quantity data for <br />the current water year, and followed by remarks if present. This is <br />followed by a TDS regression plot using the LOWESS method (see the <br />Ground Water Quality section). A statistical report representing <br />baseline (i.e., premining) data for each site downstream of mining (when <br />available) is provided in Appendix D1. On this statistics report, <br />"censored data" refers to analytical values that were below the <br />detection limit, which were censored from the min/max/mean calculations. <br />The time frame for baseline conditions is listed under "conditions <br />specified" at the bottom of each page. <br />Sage Creek <br />- Site YSSF3. This site exists on Sage Creek upstream of all potential <br />Yoast Mine discharges. It displays a decreasing TDS trend. <br />- NPDESI2. Mining in this basin began in 2000. Reconstruction of the <br />water augmentation Pond Y1 (Site YSSF2) was completed on September 13, <br />1999. It is now referred to as Pond 012 (NPDESI2) . This pond began to <br />flow again (after reconstruction) in April 2000. Flow at this pond is <br />continuous. The average flow value for this year was 0.1250 cfs, which <br />was 42% greater than the historic (2000-2010) average for Pond 012, <br />0.0879 cfs, but was 3% less than the Pond Y1's historic (1991-1999) flow <br />value, 0.1293 cfs. The timing of when flow values are collected affects <br />8