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<br />• <br /> <br />fluoride, iron and manganese were exceeded at certain monitoring wells. <br />In the area surrounding Yoast, ground water is not being pumped for <br />irrigation or livestock watering purposes, nor has the CDPHE classified <br />any aquifer in this region for any use. The above discussion is provided <br />only to serve as a comparative basis to judge ground water quality. <br />In the Probable Hydrological Consequences (PHC, Tab 17, Attachment 17-5) <br />section of the Yoast Mine PAP, predictions were made as to the expected <br />TDS increases to be observed at various monitoring wells. The following <br />table outlines these predictions along with this year's observed average <br />values (annual average for bedrock wells, May-September average for <br />alluvial wells). <br />Well Predicted TDS values <br />YOV28 2587 <br />YOV29 3201 <br />YOV30 3201 <br />YW28 3045 <br />YV129 2570 <br />YW30 2570 <br />yyN29 2670 <br />YWU30 2670 <br />YWC33 2721 <br />YAAL14 2036 <br />YGAL15 3548 <br />YGAL16 1296 <br />YSAL1 798 <br />YSAL3 798 <br />1) This years average TDS (mg/1) <br />840 <br />Dry <br />1450 <br />910 <br />440 <br />590 <br />420 <br />1350 <br />840 <br />2660 (2530 calculated) <br />5470 (5190 calculated) <br />1340 (1280 calculated) <br />1230 (1200 calculated) <br />1030 (1030 calculated) <br />At Annand Draw alluvial well YAAL14, the TDS value observed in May was <br />2660 mg/l. This value exceeds the predicted value of 2036 mg/1 by 310. <br />The PHC predictions are based on long-term average values. Individual <br />TDS measurements will vary from year to year due to climatic conditions. <br />Precipitation values were below average in previous years. What is <br />important is what the long-term trend indicates, and not what the <br />individual values observed are. More data will be needed to determine <br />7 <br />?~ <br />