URANIUM MINING IN THE AMERICAN SOUTHWEST: CAN MEDICAL GEOLOGISTS ASK THE RIGHT QUESTIONS?

The debate around proposed new uranium mining in the American Southwest is fueled by uncertainties in both the health and geosciences. The controversies are centered around 2 areas: 1) the effectiveness of contaminant plume control during mining and long-term stabilization by natural attenuation and 2) potential long-term health effects for exposed indigenous populations. Strong stands are taken by proponents and opponents of new mining on places such as the Navajo Reservation. In many cases, the disagreements are related to the practice of predicting future system performance and health effects by extrapolating from historical health data and engineering case studies that may not applicable to site-specific proposed mining practices or conditions.

Demonstration of the efficacy of site restoration to the earth scientist rests on assurance that a low-concentration plume will dissipate, be irreversibly sequestered or have no potential to reach a susceptible population. This is difficult because of uncertainties in both geochemical and hydrologic data. This presentation will provide an overview of relevant aspects of in situ mining and assessments of the potential role for natural attenuation as predicted by laboratory, field and modeling studies.

For the health professional, acceptance for future mining will require demonstration that vulnerable populations will not be negatively impacted by uranium exposures. This depends, in part on demonstrating that current exposure limits are sufficiently protective of susceptible populations. This talk will highlight some of the major uncertainties in the data and methods used to determine the possible risks to potentially exposed populations, including challenges to assessing low-level, chronic exposures and identifying relevant health effects.

It may not be possible to obtain agreement between the opposing sides in the debate over uranium mining, however, a holistic approach, which addresses the relative importance and uncertainties of key parameters and models is needed to advance the discussion. This talk will attempt to identify the reducible and irreducible risks associated with new uranium mining and explore the potential role of Medical Geology in bridging the gap between the sciences and sides in this controversial debate.