In a small victory for environmentalists, the Bush administration is expected today to endorse tougher environmental rules for hard-rock mining on federal land. The rules, which were finalized at the end of the Clinton administration, set new groundwater and surface-water standards, and allow the feds to turn down a mining permit if the mining would cause “substantial irreparable harm.” They also require mining companies to put up enough money to pay for cleanup of sites they abandon. Enviros had expected Bush to water down, or even repeal, the rules. Earlier this month, 14 moderate Republicans in Congress asked President Bush not to toss out the rules, and Congress next week is scheduled to debate still more stringent rules.