Detection of Lixiviant Excursions with Geophysical Resistance Measurements during In situ Uranium Leaching

摘要

As with many new technologies, the rapid growth in solution mining for uranium has created uncertainties regarding the environmental impact of mining operations. In solution mining, the largest area of concern is the impact of the process on the quality of ground water supplies. As a result, a rapid and reliable technique of detecting lixiviant excursions is desirable. Such a method would replace the periodic sampling technique and should provide a more or less continuous monitoring method. To this end, resistivity techniques were evaluated as an alternate means of tracking lixiviant movement. A program was devised with five specific tasks including (1) evaluation of the techniques, (2) development of most promising technique or techniques, (3) field testing of the techniques, (4) testing of the Bureau of Mines probe, and (5) reporting. The result of the analytical and field work is that various resistivity-resistance techniques do provide a means of detecting lixiviant movement in northern Wyoming. Surface and downhole galvanic surveys and controlled source audio magnetotellurics were evaluated. All three techniques showed some degree of success.