The US administration scheduled an announcement Monday widely expected to implement a long-term ban on mining around the Grand Canyon, a move praised by environmental activists.
The Bureau of Land Management has already recommended a 20-year ban on new uranium mining claims for more than 400,000 hectares (one million acres) of federal land near the Grand Canyon.
Interior Secretary Ken Salazar has scheduled an announced at 1600 GMT "regarding conservation of the Grand Canyon," according to his office.
Jane Danowitz of the Pew Environmental Group said the announcement means "Americans can celebrate today that the Grand Canyon is protected for future generations to enjoy."
She also called for reform of "the nation's antiquated mining law," which she said gives the industry "unfettered access to the majority of public lands in the west."
Salazar imposed a two-year moratorium on new mining around the Grand Canyon in 2009, to give his department time to study a long-term ban. In June, he extended the moratorium for an additional six months. He has said that he prefers a long-term ban but would await the bureau's recommendation.
A number of Republican lawmakers from the region have opposed the ban.
Senator John McCain and other lawmakers from Arizona and Utah sent a letter last year to Salazar claiming any new ban would create a "de facto wilderness" zone in a region that "conservationists previously agreed would remain accessible to the mining industry."
McCain's group has introduced a bill to enshrine what he called a "historic agreement" in 1984 "that designated parts of the Arizona Strip as wilderness and restored other lands to reasonable and safe uranium mining uses."
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