Great Sand Dunes National Park Superintendent Art Hutchinson was walking in the remote south-central Colorado preserve last year when he was startled by the ringing of bells from a Catholic monastery 8 miles away.
"If I'm hearing these bells," he recalled this week, "they can hear what sounds are out here," in the park, home to North America's highest dune, formed by ancient lake sediments piled high by winds from the nearby Sangre de Christo Mountains.
Then he thought about an energy company's pending proposal to drill two oil and gas exploratory wells in the adjacent Baca National Wildlife Refuge, 2 miles from Great Sand Dunes' western border, and another realization sunk in.
What was later confirmed by NPS's Natural Sounds Program Office to be the quietest national park in the United States could become an echo chamber for the state's burgeoning energy industry, Hutchinson feared.
Now Great Sand Dunes is at the center of a lawsuit and growing national debate about the effects of sound pollution in national parks and wildlife refuges like Baca.
Two environmental groups are suing the Fish and Wildlife Service to block the issuance of permits to Toronto-based Lexam Explorations Inc. that would allow for the drilling of two 14,000-foot-deep wells on the Baca refuge. Their argument hinges in part on sound monitoring data collected by the National Park Service in Great Sand Dunes, which they maintain would be ruined by the pounding hydraulics and thundering machinery of oil and gas wells.
A federal judge in Denver last month handed a partial victory to the environmentalists by issuing an injunction against any drilling at Baca until the lawsuit is resolved. U.S. District Judge Walker Miller concluded that plaintiffs "presented adequate evidence that the drilling of these wells is likely to cause irreparable injury" not only to wildlife but also to the refuge's "significant 'sense of place' and quiet."
If Miller's view becomes law, it could have far-reaching effects, park advocates say, by forcing federal agencies nationwide to more seriously evaluate the natural soundscapes of the lands they manage when permitting nonconforming projects, including road building, logging, energy development or other activities.
"Noise pollution, like light pollution, is becoming an increasingly big problem at our parks," said Bryan Faehner, associate director for park uses at the National Parks Conservation Association. "The uniqueness of a national park and the special experience you can have at a park is less special if you can't see the stars or if you can't listen to the amazing songs of migratory birds."
Faehner pointed to a recent string of court decisions endorsing the notion of natural soundscape preservation at national parks, including U.S. District Court Judge Emmet Sullivan's landmark 2008 ruling that the managers of Yellowstone National Park must account for snowmobile noise in the park's winter use plan. Among other things, Sullivan wrote that stewardship of park resources "apply equally to the conservation of the parks' natural soundscapes."
And while the 1916 legislation creating the Park Service orders the agency to preserve natural soundscapes along with the scenic vistas and wildlife at each park property, only a handful of the 391 park units nationwide address sound issues in their general management plans. And none have formalized parkwide sound management plans, despite a 2000 NPS director's order that called on park managers to develop plans "to preserve and/or restore the natural resources of the parks, including the natural soundscapes associated with units of the national park system."
So far, two park units -- Zion National Park in Utah and Minute Man National Historical Park in Massachusetts -- are writing noise action plans that will be incorporated into park management rules, said Frank Turina, a planner with the agency's Natural Sounds Program.
The value of sound, or no sound
The Baca wildlife refuge drilling controversy further highlights the Park Service and Interior Department's ongoing struggle to balance conflicting land uses and competing public interests on federal lands. And for critics of government regulation, it raises the thorny proposition that even activities not directly occurring on a park property may somehow be subject to government restrictions.
Stefan Spears, vice president of strategic development for Lexam, said the company went to extra lengths to address noise concerns, which included an agreement to use quieter diesel-powered rigs and fit "muffling equipment" on all engines used in the field.
"We were disappointed," Spears said of Miller's injunction. "We're going to try and keep things on track and see if it can ever reach a logical conclusion."
The Park Service, too, has been trying to reach a logical conclusion about noise in parks since 2000, when it quietly launched a research program aimed at determining whether cars and trucks, maintenance equipment, park buildings and recreational vehicles such as Jet Skis or off-highway vehicles (OHVs) diminish the enjoyment of park visitors by filling their ears with unnatural sounds. A separate line of research is examining the effects of noise pollution on wildlife in the parks.
The goal, according to Park Service officials involved in the effort, is for each park unit to have a sound management plan that accounts for the variety of unnatural noises at each park and ways to mitigate such disturbances.
"When people talk about hearing quiet or having a quiet experience, you hear them use words like 'soothing' and 'peaceful,'" said Peter Newman, an expert on protected areas management at Colorado State University in Fort Collins. "An essential part of the park experience is to have relaxation."
According to visitor surveys done by Colorado State researchers on behalf of the Park Service, the hearing of natural sounds remains an important component of park visitors' experiences. Among the sounds visitors most value in park settings are the movement of water and wind and bird songs, said Newman.
Such findings support NPS's own extensive surveys, done nearly two decades ago and reported to Congress in 1994, which found that roughly as many people said they were visiting a park to enjoy "natural quiet" as to take in the visual beauty of the place.
Among the sounds that visitors do not want to hear, surveyors found, are loud talking, truck and car engines, and aircraft noise, Newman said.
Meanwhile, a growing body of research suggests that certain unnatural sounds -- particularly loud, repetitive noises -- affect wildlife and impede certain animals' ability to evade predators. Other research has found that such noises can disrupt the breeding cycles of some animals and may even discourage birds from singing.
In a forthcoming analysis to be published in the journal Trends in Ecology and Evolution, Park Service and Colorado State researchers cite clear evidence that unnatural sounds can be highly disruptive in natural settings, with a range of impacts from mountain goat migration times to habitat locations chosen by greater sage grouse and mule deer.
Among the findings cited by the NPS and CSU researchers was a 2007 investigation by the University of Alberta that found noise from compressor engines at oil and natural gas drilling sites created a "significant reduction" in ovenbird pairings. "We hypothesize that noise interferes with a male's song, such that females may not hear the male's song at greater distances, and/or females may perceive males to be of lower quality because of distortion of song characteristics," the researchers wrote (Land Letter, Aug. 7, 2008).
Similarly, a 2006 study by the University of California, Davis, found that noise from wind turbines in remote sections of Northern California interfered with the ground squirrels' ability to warn each other about approaching predators.
These and other findings prompted Park Service and Colorado State researchers to conclude in their upcoming analysis that "the preponderance of evidence argues for immediate action to manage noise in protected natural areas."
Moreover, they noted, "Quieting protected areas is a prudent precaution in the face of sweeping environmental changes, and a powerful affirmation of the wilderness values that inspired their creation."
But questions remain about whether the proposed drilling project at Baca National Wildlife Refuge should be subject to restrictive noise standards.
The case is complicated by a number of factors, including that Lexam acquired mineral rights on the Baca ranch before Congress authorized purchase of the 92,500-acre property in 2000 and designated it a wildlife refuge. Lexam has sought to move quickly on its drilling project because the surface-use agreement it negotiated with the property's previous owner expires in 2011.
The company has already obtained the necessary permits to drill from the Colorado Oil and Gas Conservation Commission, and drilling would not last more than 180 days and would directly effect 14 acres, according to court records.
The Fish and Wildlife Service, in its final environmental review of the project, concluded that the initial drilling activity would have no significant impact on the surrounding environment. If the exploration revealed large deposits of oil or gas, regulators would complete another environmental analysis before the project could proceed to the development phase.
The two plaintiffs in the lawsuit -- the San Luis Valley Ecosystem Council and the Citizens for San Luis Valley-Water Protection Coalition -- argue that Lexam officials had undue influence over the environmental assessment process and that the focus of the assessment's scope was narrowed to avoid examining concerns about noise on the refuge and the adjacent Great Sand Dunes National Park.
"We just thought it was a very superficial analysis," said Christine Canaly, director of the San Luis Valley Ecosystem Council in Alamosa, Colo.
NPS also was not happy with the analysis, submitting comments criticizing FWS for failing to adequately analyze the project's noise impacts on the park, much of which is designated wilderness.
Among the points NPS's Hutchinson challenged in the FWS document was a finding that the proposed drilling would not be audible "under most atmospheric conditions." In submitted comments, Hutchinson said a review of FWS's analysis "does not allow us to reach that conclusion."
Hutchinson further noted that the criteria FWS used to analyze noise impacts was "designed for use in urban areas when studying the impact of aircraft noise on humans during the nighttime hours.
"These are inappropriate metrics for use in a natural area, particularly an area adjacent to a unit of the National Park System," Hutchinson said.
Perhaps most critical, however, are the NPS sound studies carried out by the agency's Natural Sound Program, which found the Great Sand Dunes park is exceptionally quiet.
"We view the soundscape or the acoustic environment as a resource to be protected," said Karen Trevino, director of NPS's Natural Sounds Program. "From our perspective it goes to the heart of what we are in protecting these resources."
At least for now, however, FWS has no plans to revise its findings.
"Right now, we'll wait," said Michael Blenden, FWS project leader for the San Luis Valley National Wildlife Refuge complex, which comprises three refuges in south-central Colorado, including Baca.
Scott Streater is a freelance journalist based in Colorado Springs, Colo.