U.S. uranium mining companies are still interested in developing mining operations in New Mexico land occupied by the Navajo Nation, as estimates suggest there might be up to 70 million tons of naturally occurring uranium buried underground, the Farmington Daily Times reported.

Over the past few years, a number of mining companies have been attempting to gain permission to resume work on the uranium-rich sites but to no avail. The Nation banned mining for uranium in 2005. According to Mat Leuras, vice president of corporate development for Albuquerque-based Uranium Resources Inc., the problem was rooted in the history of the land, as the Navajo Nation opposes potential mining operations because of the legacy related to the site.

Digging for uranium was allowed between the late 1940s and the 1980s, when approximately 4 million tons of uranium were extracted from the Navajo Nation land. Back then, the radioactive ore was used to manufacture nuclear weapons that the United States needed for World War II and the Cold War. Uranium was extracted through traditional mining procedures, which allowed uranium to seep into the land and water in the surrounding area. A number of environmental studies carried out have shown increased levels of uranium around the mines, causing health problems for miners and communities living in the vicinity of mines.

Companies looking for permission to resume uranium-mining have claimed that there would be no threat to residents near the mines. New, more advanced technologies and better precautionary measures can protect both the environment and the people, as businesses operating in the industry have learned from their past mistakes, Leuras stated.

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Even if the Navajo Nation does not allow mining on its land, companies still can extract uranium around the tribal territories where there are deposits. Uranium companies including Uranium Resources Inc., Strathmore Minerals Corp., Rio Grande Resources and Laramide Resources Ltd. have all made investments and are set to begin digging for uranium around the reservation border. Still, in certain cases the companies need access on the Navajo land to reach their projects.

These days, the majority of companies utilize the so-called "in-situ" approach, in which they use injection wells and extraction wells to circulate water through an underground body of ore. Although the water does not contain any chemicals, it removes the uranium without damaging the rock, Uranium Resources' website explains. This process is believed to be more cost-effective and safer than conventional underground mining.

However, environmental groups and the majority of the Navajo community are still concerned about the safety of those operations. Stephen Etsitty, executive director of the Navajo Environmental Protection Agency in Window Rock, said that he was not considering any new uranium mining operations because he was concentrating on "addressing the long overdue and enormous workload associated with the remediation or clean up of past uranium mining and processing," he told the Farmington Daily Times. Data from last month's report from the U.S. Environmental Protection Agency reveals that over $100 million has already been spent on clean-up of tribal properties and resources affected by higher levels of uranium.