Laserfiche WebLink
The Engleville Mine Discharge (EMD) was also measured on a quarterly basis <br />throughout the year. The attached analysis shows no problem with pH, conductance, <br />temperature or any dissolved ions, however the December sample showed no discharge <br />from the sampling point. During the previous three quarters, flow was approximately <br />1/4 gpm. It is believed that the lack of discharge in December was due to the <br />extremely dry summer providing little recharge into the old Engleville Mine. The lag <br />effect of these dry conditions was not seen in the mine discharge until December. <br />Also, since the previous flows were only approximately 1/4 gpm, dry conditions could <br />easily have stopped flow. The Rimrock Mine did not disturb any strata in the Vermejo <br />Formation on the east side of Engleville Gulch, where the EMD is located. <br />Ground Water- Year 1994 <br />During 1994, the Montoya dug well, the USGS well and Monitoring well 29-4 were <br />monitored on a quarterly basis. All analysis and lab test results are attached. The <br />water levels for all wells remained relatively constant although the Montoya dug well <br />went dry in December. <br />This is not a cause for alarm due to the following reasons: 1) the Montoya well is <br />hand dug and its total depth is only approximately 60 feet. Normally, water levels are <br />44-57 feet, so water levels do not need to drop much for the well to run dry. As is <br />seen from the previous graph, some pre-mine well levels almost reached well bottom, <br />2) the summer of 1994 produced record droughts which always have a delayed effect <br />on ground water levels. The Engleville Mine Discharge (EMD) also went dry in <br />December of 1994, which is located on the opposite side of Engleville Gulch from the <br />Rimrock pit and could not have been affected by the mine operation or reclamation, <br />and 3) if the mine affected levels in the Montoya well, it should also have affected <br />levels in the USGS well, which is located between the Montoya well and the Rimrock <br />pit. The samples show no significant change in levels at the USGS well. <br />Also evident from the analysis is the fact that the specific conductance of the USGS <br />well rose significantly in the second half of 1994. 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/] to <br />4788 mg/1 in the last two quarters (3rd and 4th quarters of 1994). Checking the lab <br />ion analysis from the 4/12194 sample to the 7!21194 sample showed that the following <br />ions were primarily responsible for the increase in the salt content: <br />