Air and water quality, national parks and surrounding communities, and clean energy development will be hard hit by across-the-board spending cuts in the federal budget that took effect today. President Barack Obama and Congressional leaders came out of a White House meeting this morning without resolution to the budget impasse, known in Washington as the sequester.

Peter Butler's late October tour of abandoned hardrock mines began high on Red Mountain Pass near Silverton, Colo., off a highway so narrow that, in places, its shoulder crumbles off cliffs. Butler, a water wonk with springy silver curls, is the co-coordinator of the Animas River Stakeholders Group, a local watershed group, which has been cleaning up abandoned mines for 18 years.

As many people know, the astounding increase in agricultural output that marked the latter half of the 20th century came at a high environmental price. Agriculture is a major contributor to global warming, and runoff from farm fields helps pollute rivers and streams.

On Thursday, one of the country's most effective environmental laws — the federal Clean Water Act — will turn 40.

A long-running battle over Clean Water Act policies took another turn this week, as the U.S. House Appropriations Committee voted to block the Obama administration from implementing new policy guidance that would reinstate protections removed by the Bush administration.

In a case watched closely by energy companies and manufacturers, the Supreme Court is set to consider Monday whether to blunt one of the government's chief tools for enforcing the Clean Water Act.