Obama bans new mining claims near the Grand Canyon January 9, 2012 -- Updated 2237 GMT (0637 HKT) The 20-year ban affects more than 1 million acres of public land The area is rich in uranium Environmentalists cheer the decision as a way to protect the park and water supplies Arizona Gov. Jan Brewer says it will stall economic growth Washington (CNN) -- The Obama administration on Monday announced a 20-year ban on new mining claims on more than 1 million acres of public land near the Grand Canyon, a move meant to protect the iconic landmark from new uranium mining. Previously-approved operations will be allowed to continue, as will new projects on valid existing claims. People from all over the country and around the world come to visit the Grand Canyon. Numerous American Indian tribes regard this magnificent icon as a sacred place and millions of people in the Colorado River Basin depend on the river for drinking water, irrigation, industrial and environmental use," said Interior Secretary Ken Salazar. "We have been entrusted to care for and protect our precious environmental and cultural resources, and we have chosen a responsible path that makes sense for this and future generations," he added. The administration said the move will give officials more time to monitor the impact of uranium mining on the vital watershed, and in the mineral-rich area in general. Conservation groups cheered the decision, which was slammed by Arizona Gov. Jan Brewer and Sen. John McCain. "This is a great day for Grand Canyon National Park and all those who care about the park and the surrounding public lands and waters," said Sandy Bahr, Grand Canyon chapter director of the Sierra Club, a California-based environmental organization. Today's decision protects not only the area around the Grand Canyon, but water that helps feed the Colorado River, which provides drinking water for millions of people downstream. Brewer similarly stressed the significance of the park, but argued the move will needlessly cost Arizona jobs and stall economic growth. "The 20-year ban comes at the expense of hundreds of high-paying jobs and approximately $10 billion worth of activity for the Arizona economy," she said. Nobody wants to see it (the Grand Canyon) harmed. But I believe that environmental protection and economic growth are not mutually exclusive. We could and should have both. The Grand Canyon National Park is a major tourist attraction in Arizona; close to 5 million people visit it each year. McCain, speaking Sunday before the ban's official announcement, said he had expected the decision and was disappointed. "It's clearly another victory for the radical environmental community," he said.