Excluding excessively intrusive noise from national parks and other federal recreation lands is going to be a whole lot easier when the legal system clearly and consistently recognizes natural sound as a resource deserving rigorous protection. Much progress has already been made in the area of reducing excessive noise related to commercial flightseeing operations in park airspace. Now environmentalists are targeting other noisy activities, including drilling operations. A recent federal ruling on drilling noise in a Colorado wildlife refuge indicates that the courts may be lending a friendly ear to arguments for tighter controls on drilling in and near federal recreation lands.

After an oil and gas drilling operation was proposed in the Baca National Wildlife Refuge adjacent to Colorado’s Great Sand Dunes National Park, the National Park Service’s Natural Sounds Program deployed an acoustic monitoring team to the park. Focusing on the area nearest to the wildlife refuge, which is situated along the park's western border, the team took a series of careful measurements extending over the period September 24 to October 10, 2008.

What the acoustic monitoring revealed was truly remarkable. The readings obtained at the park were some of the lowest levels ever measured by the Natural Sounds Program, rivaling even those of super-quiet Haleakala Crater. In fact, it’s so quiet at Great Sand Dunes that future monitoring in the park will have to employ a high-sensitivity microphone to more accurately measure the extremely low sound levels existing there.

The Natural Sounds Program study at Great Sand Dunes proved consequential. Environmental groups filed suit in federal court, arguing that oil and gas drilling would cause irreparable injury to Baca National Wildlife Refuge (and by inference, to Great Sand Dunes National Park). Results of the Natural Sounds Program study of Great Sand Dunes were submitted as evidence that natural quiet prevails in the wildlife refuge vicinity.

U.S. District Court Judge Walker Miller found the environmentalists' argument persuasive. In September he issued a preliminary injunction that blocked drilling in the Baca National Wildlife Refuge while the case moved forward. In his ruling, Judge Miller noted that the refuge not only contains important wetland habitat for wildlife and fish, but is also a "large expanse of undeveloped land with a significant sense of place and quiet.”

Subsequent developments related to this case will be watched with great interest. If drilling activities on federal lands were to be severely constrained in order to protect natural soundscapes, there would be far-reaching consequences. The economic, political, and social impacts would be especially profound in Utah, western Colorado, Wyoming, and other regions of the country where national forests and wildlife refuges with important hydrocarbon deposits lie cheek-by-jowl with national parks. Environmentalists campaigning to prevent oil and gas drilling in Alaska's Arctic National Wildlife Refuge (ANWAR) would also regard a greater federal commitment to soundscape protection as another arrow in their quiver.