The U.S. government says there has been no doubt that it intends to proceed with a land exchange in Arizona for a planned multibillion-dollar copper mine, telling the U.S. Supreme Court that its recent notice of publication of a final environmental impact statement for the project does not constitute urgent review. There is nothing about the 60-day notice, which was filed in an Arizona federal court and published in the Federal Register on April 17, that supports claims by the Apache Stronghold that there may have been some uncertainty about the federal government's intent to move forward with the land transfer, the government told the high court in a Monday letter.