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• Overall, water well sampling has not shown any significant effects due to mining and <br />reclamation. Water levels have remained fairly constant except for the last sample from <br />the Montoya well, but, as explained previously, this could not be due to the Rimrock <br />excavation. Levels of pH have remained very steady, as expected. The Raton Basin is <br />not known for acid water production from its coal seams. The specific conductance ( a <br />function of total dissolved solids) has dropped in Well 29-4 upstream and in the <br />Montoya well, but has increased in the USGS well from approximately 3641 mg/I to <br />4788 mg/I in the last t~vo quarters (3rd and 4th quarters of ]994). Checking the lab ion <br />analysis from the 4/12/94 sample to the 7/21/94 sample showed that the following ions <br />were primarily responsible for the increase in the salt content: <br /> <br />• <br />Ion A r 12, 94 Jul 21, 94 Increase <br />Calcium 189.8 386.3 196.5 <br />Magnesium 57.4 122.7 65.3 <br />Nitrogen-Nitrate 6.9 26.98 20.08 <br />Sodium 494 598 104 <br />Sulfate 1298.4 2106.9 808.5 <br />Total Selected Ions 2058.5 3261.88 1203.38 <br />It is not possible that the increase in ion content was due to fertilization since records <br />show that the fertilizer applied vas 18%N and 46% P, which is a common single <br />chemical fertilizer using di-ammonium phosphate. The only ions added to the ground <br />were (NH,,)" and (PO, J' . A quick check of the lab analyses shows that these ions did <br />not increase at all for the samples in question. The sulfate anion in combination with <br />calcium, magnesium and sodium were primarily responsible for the increase. This <br />increase could not have come from the Rimrock pit altering the flows of water in the <br />Engleville Mine workings since all encountered entries were dry and the historic quality <br />of the Engleville Mine discharge does not contain such a high salt level. <br />In general, the ions that showed increases were already present in the water in <br />significant levels. It appears that the water increased in salt content through <br />concentration, possibly due to evaporation of the shallow water near the USGS well <br />during the dry 1994 year. Also, the ions which increased are not dangerous or toxic. <br />The other holes have not experienced this increase in specific conductance because the <br />water levels are much deeper from the surface and would not be affected to the degree <br />experienced at the USGS well. <br />2.07(1) Page la 1/12/95 <br />~f< i <br />