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being able to complete any of the as-built surveys on these <br />particular stocktanks. As soon as weather and ground <br />conditions allow us this spring, these surveys will be <br />conducted and the as-built reports submitted to the Division. <br />5. The hydrologic monitoring program has been reorganized as <br />requested. Table 7-99 provides ground water monitoring <br />frequencies and Table 7-103 provides surface water monitoring <br />frequencies. <br />SCC proposes several changes to the current hydrologic <br />monitoring program. These changes are given in the following <br />paragraphs. <br />Ground water level measurements, currently being performed <br />five times a year (February/March, April/May, June/July, <br />August/September, and October/November), are proposed to be <br />performed three times a year (May/June, July/August, and <br />October/November). SCC currently has sixteen years worth of <br />water level data (at the five times a year frequency) for most <br />wells, which has well established the hydrologic <br />characteristics of water level fluctuations. Triannual <br />monitoring will still detect the seasonal variability of water <br />levels in the wells. This monitoring frequency is similar to <br />that recently.approved by the CDMG for SCC~s Yoast Mine. <br />Wells GW-S1-U and GW-S2I-LWI monitor a pre-SMCRA mine pit <br />• which was used by the Hayden Station power plant as a fly-ash <br />disposal area. All monitoring of these wells is proposed to <br />be discontinued since it is a pre-SMCRA area and since <br />seventeen years worth of data has well established their <br />hydrologic characteristics. <br />Wells GW-S70-A and GW-571-A (lower and upper Grassy Creek <br />alluvial wells), were drilled in 1988 as a result of an <br />internal review of hydrologic monitoring conducted by Peabody <br />Western Coal Company. Both wells have been voluntarily <br />monitored for water levels and quality since drilling. Both <br />these wells will now become part of the established monitoring <br />program. Hydrologic reports for these wells have been included <br />in the permit renewal (Tab 7, Hydrology). <br />Stream site SW-S2-5 is located on Little Grassy Creek upstream <br />of mine discharges. This ephemeral/intermittent stream is a <br />relatively minor contributor to the flow in this basin. <br />Average flows for May, June, July, and August were 96.8, 13.7, <br />4.4, and 1.5 gpm, respectively. Also, this site is often dry <br />by July or August. Since seventeen years worth of monitoring <br />has well established the hydrologic characteristics of this <br />site, it is proposed that monitoring will be discontinued <br />here. <br />Stream site SW-S2-6 is located on Cow Camp Creek less than 1/4 <br />mile below NPDES 004. it was originally established to <br />