Dust on the rocks

by Keith Kloor
High Country News







Constance Silver measures dust in Nine Mile Canyon.




Last summer, Constance Silver spent a week examining the world-renowned rock art in Utah's Nine Mile Canyon, a two-hour drive south of Salt Lake City. Tucked into the rugged Tavaputs Plateau, the place contains upwards of 10,000 images, painted and pecked onto sandstone walls. Many of them are visible from the curving, roughly graded road.

But the respected art conservator wasn't there to admire the renderings of hunters, bighorn sheep and geometric patterns. Rather, she came to study dust. More specifically, to take air samples and observe the brownish-gray clouds kicked up by an armada of oil and gas trucks as they rumbled through the canyon.

After wrapping up her fieldwork, Silver stopped by the local Bureau of Land Management office in nearby Price, which oversees Nine Mile Canyon, and sought out its lone archaeologist, Blaine Miller. She informed Miller that the dust was having an "alarming effect" on the rock art and "had to be taken care of immediately."

"In your dreams," Miller said, recalling the exchange. His own concerns had been repeatedly ignored by his superiors since 2004. That was when the Bill Barrett Corporation, a Denver-based energy company, began exploratory drilling for natural gas higher up in the plateau, using Nine Mile's rutted road as the main transportation route.

Silver, who specializes in restoring vandalized rock art, became adamant, according to Miller. "No, not in my dreams," she insisted. "It has to be taken care of now."

A year has passed since that conversation, however, and nothing has been done to solve the problem. Not only that, but Silver's original findings have essentially disappeared. Hundreds of documents obtained recently through the Freedom of Information Act reveal that crucial data and other supporting evidence attesting to severe dust contamination never made it into her study, which was released last February. These omissions enabled the BLM to cast Silver's report as inconclusive, at a time when the agency was approving a controversial proposal for expanded drilling by Barrett. It's not clear exactly what happened to the study or why, but the story of how it got watered down provides a window into the murky mingling of science, industry and an underfunded federal agency faced with an onslaught of energy development.

The doctored study is just one of many questionable actions taken by the BLM during the past five years relating to gas drilling impacts in Nine Mile Canyon. To many critics, the crowning insult came earlier this year, when the BLM issued its draft environmental impact statement for Barrett's 800-plus gas well project. "It is the worst document I have seen in my 30 years working in the BLM," Miller told me recently. Forbidden to participate in the review, Miller, who is an expert on Nine Mile Canyon, wasn't even permitted to see the document until it was released to the public. "There's nothing in there about how bad the dust is, what the effects are on the rock art, no attempt to mitigate any of it."

For decades, scientists and rock art buffs have marveled at the prehistoric carvings and paintings in Nine Mile Canyon. Even the BLM has acknowledged Nine Mile Canyon's importance, calling it the "largest concentration of rock art in North America."

Most of the pictures were left by the Fremont people, a culture of farmers and foragers that thrived throughout Utah a millenium ago, before leaving the area around 1350.

As recently as the 1990s, the Price BLM office had put Nine Mile's archaeological treasures front and center, writing a management plan that, according to Miller, would showcase and protect the rock art.

Then, in 2005, after several years of exploration, geologists for the Bill Barrett Corp. hit a sweet spot in the Tavaputs' ancient bedrock, with extractable gas deposits estimated to be worth $2.5 billion. The company quickly applied for a "full-field" development, which requires an environmental impact statement (EIS) to evaluate potential negative affects. The exhaustive assessment often takes years to complete, but that hasn't slowed down Barrett. To date, the company has drilled 200 of its proposed 800 gas wells, nearly half of them under "categorical exclusions," a provision in the 2005 Energy Act that allows the BLM to give the go-ahead to a variety of projects without doing an environmental review.

By 2006, however, the traffic and dust in Nine Mile Canyon had become so bad that the BLM had to respond to growing complaints by archaeologists and environmentalists. The agency called on Silver to assess the problem. The initiative stalled, though, after the BLM was unable to secure government funding. Barrett then agreed to pay for the study. By the time Silver arrived on the scene last summer, some 350 trucks and rigs were barreling through the canyon on any given day.

In the following months, as Silver worked on the dust study, her worst fears were confirmed by a series of lab analyses. Each time something noteworthy turned up, she e-mailed the person who hired her, Nine Mile Canyon's supervisory archaeologist, Julie Howard, who works out of BLM's Division of Land and Minerals office in Salt Lake City.

In early October of 2007, Silver advised Howard of the likelihood that magnesium chloride was being "tracked all through the canyon." For years, the Barrett Corp. had extensively applied the chemical dust suppressant -- essentially a salt -- along portions of the Nine Mile road. And over the years, the industrial flotilla has pulverized the unstable roadbed, creating an airborne potpourri of silt, diesel fuel and chewed-up magnesium chloride, which is notoriously corrosive to concrete, cars and just about everything else.

In that same e-mail, Silver also told Howard that the dust "all over" the Great Hunt panel -- Nine Mile Canyon's most iconic and frequently photographed image -- had the same chemical "signature" as the dust produced in the air along the adjacent stretch of the road by passing oil and gas trucks. Her other test samples of rock art sites in Nine Mile Canyon had shown a similar pattern. "So, at the very least, dust is getting all over the rock art," Silver wrote. "At the very worst, it is contaminating the rock art with magnesium chloride."

Silver explained to Howard that "the presence of magnesium chloride in dust could become a critical marker for how the Nine-mile road is producing and spreading dust." Puzzling this out -- and determining the extent of the overall problem -- would be huge, but Silver wanted to be sure, so she had the lab run a second set of tests. At the end of October, Silver informed Howard that the final lab results were in: "They found magnesium chloride all over the place, alas."

Two months later, in early January of this year, I met up with Silver in New York City, while she was working on a restoration project at the Guggenheim Museum. Clad in frocky work clothes stained with plaster, the Vermont-based conservator talked proudly of her study at Nine Mile Canyon. Previously, little research had been done on the impacts of dust on rock art -- a worldwide issue -- so she believed her contribution would fill in a significant academic gap.

Silver sounded sure of her findings, stating unequivocally that magnesium chloride-laced dust was being kicked up by trucks and was "going all over the place and settling on the rock art." She was particularly "alarmed" by "all these little crystals of magnesium chloride getting into the pores of the rock art."

"It's such vicious stuff," she added. "It peels concrete, corrodes it."

I was surprised by Silver's certainty, because the last time we'd spoken about her study, over the phone in September, she made a point of telling me how difficult it might be to distinguish current impacts to Nine Mile Canyon from those that began a century ago, when homesteaders first arrived. During that period, the main road through the canyon was also used as a freight route, which no doubt produced its share of dust. Bored cowboys and stagecoach drivers were fond of using the rock art panels for target practice. Later, pothunters and tourists started leaving their own stains on the landscape.

"Let's face it, (Nine Mile Canyon) is not a pristine environment," she said to me. "What I was concerned about was how much of the dust is coming from current use and how much from 100 years of mistreatment. I was worried from the beginning how we were going to figure that one out. But now when you get the magnesium marker, you can pretty much say you're getting a really accelerated settlement of dust."

Silver was not opposed to Barrett's operation herself, but she believed her study results were so "harsh" that some environmental groups might seize on them to try to stop it. In 2004, activists and archaeologists had unsuccessfully sued to halt the company's incursion into Nine Mile Canyon.

They never got the chance, however, to use her results, because the version of her study published in early February contains none of the relevant, damaging information Silver expressed either to me or in her e-mails to Julie Howard.

In fact, Silver's published study makes no mention of the positive magnesium chloride finding throughout the canyon. Instead, it describes the difficulty of separating out the historical and naturally occurring dust and concludes that "thus far it has been impossible to isolate and identify magnesium chloride in the laboratory."

After learning of the e-mail exchanges between Silver and Howard, Nine Mile advocates are seething. "All these years, we thought they (BLM) were just being irresponsible," says Utah archaeologist Jerry Spangler, an expert on the canyon. "Now it's moved to willful, intentional deceit to benefit an agenda and one particular developer, and that's really disturbing."

If relevant lab results were intentionally excluded from the EIS, it was "a violation of NEPA (the National Environmental Policy Act), which in the full spirit of disclosure, the federal government is supposed to present the most recently available information, not that which supports an industry project," says EPA's Larry Svoboda, a Denver-based director of the agency's NEPA program.

In a recent phone interview, Howard said no such intent existed. "To the best of my knowledge, we included everything we knew at this point," she said. But when confronted with e-mails showing that she knew about the excluded lab results at least four months before the EIS was published, Howard claimed that the results didn't get into the impact statement because the deadline had already passed. "We weren't trying to hide anything," Howard insists.

Barrett's involvement in the study also seems to be a point of confusion for Howard. She first said that the gas company "never saw the study until it was done." However, an extensive e-mail paper trail reveals that Howard kept Barrett officials abreast of Silver's progress, even giving them a chance to weigh in on draft reviews and participate during conference calls. In August, Duane Zavadil, Barrett's vice president for environmental regulatory affairs, confirmed that company officials saw the study before it was released to the public. However, he says: "We didn't provide a single editorial comment. We never asked for a word in the report to be changed."

Still, that the energy company paid for the study and was then allowed to review drafts before it was released "suggests that the process was biased," says Jeffery Clark, an archaeologist with the Tucson-based Center for Desert Archaeology. At a minimum, Clark says, the BLM should have put up a firewall between Silver's study and the company. "If data was withheld, then that's illegal," he adds. "That's like an archaeologist finding a site where the development is taking place and not recording the site. That would be grounds for shutting down the project."

Before any of this would be known, the BLM was already getting hammered from all sides regarding the Barrett EIS it released in February. In recent months, major concerns over ozone pollution, stream contamination, disappearing wildlife habitat, and of course, continuing destruction to the rock art, have poured in from many quarters, including the Utah governor's office, environmental groups, the Hopi (who claim ancestral ties to Nine Mile), and lately, the Environmental Protection Agency, which gave the EIS a failing grade for faulty air modeling of emissions.

Clearly, though, both the BLM and Barrett are most skittish over the allegations of dust damage to the canyon's rock art. When I spoke to BLM managers and Barrett executives in the spring and summer, they repeated the same talking point: Silver's findings were inconclusive. In a May editorial published in a local paper, a Barrett official even cited her study to defend its use of magnesium chloride, which it had applied again that month.

Despite her role in the BLM's shenanigans, Silver obviously cares deeply about the rock art. That's evident in her comments in an early draft of her study: "During the public comment period, some years ago, several conservation scientists and conservators (including the author of this report), raised objections to the use of magnesium chloride for dust abatement in Nine Mile Canyon, because eventually some magnesium chloride will escape the road and be deposited in rock art. The potential for damage is very great, and remediation would be very difficult." Those comments do not appear in the published study.

Silver's recommendation in the next (and concluding) paragraph on how to solve the problem never saw the light of day, either: "Therefore, another road surfacing must be developed and implemented as soon as possible in proximity to all rock art panels. A very promising road surface system identified by the BLM is asphalt chunks that can be spread on the road and then packed in place. -- It is absolutely critical that this -- or some other system -- be employed as soon as possible to arrest the development of dust near the rock art sites."

Notably, this solution was never mentioned in the BLM's draft EIS of the Barrett proposal. As this story went to press, the agency was testing six different types of dust control along Nine Mile road involving the use of enzymes. Whether or not enzymes would be any less harmful to rock art panels than magnesium chloride is not known, because no studies on their impacts have been done.

The company could utilize existing roads that circumvent Nine Mile Canyon altogether. Environmentalists and archaeologists have repeatedly suggested this, but the company insists that the cost and operational constraints are prohibitive. The BLM, for its part, has never seriously considered it as an alternative.

Several groups, including the National Trust for Historic Preservation, which has listed Nine Mile Canyon as one of its nine most endangered places since 2004, are now paying for an independent engineering study to assess the viability of bypass roads.

A year after Silver conducted her study, conditions in Nine Mile Canyon remain unchanged. The road is crumbling under a steady parade of oil and gas trucks. Dust is still flying everywhere, eroding innumerable rock art panels, according to Miller and other archaeologists.

Final drafts of Silver's study and the BLM's evaluation of Barrett's drilling expansion are set to be released in the fall. At the most recent Utah BLM advisory council meeting in late June, Julie Howard assured attendees that, according to Silver's study, evidence of damage to Nine Mile Canyon's rock art from dust and magnesium chloride was "inconclusive."

Silver, for her part, seems to believe that her study was properly handled by both the BLM and the Bill Barrett Corporation. Until recently, she had not responded to repeated requests for comment on this story. Then, on Aug. 15, she sent me an e-mail stating, among other things: "The work that I am doing in Nine Mile Canyon -- with the full support of the BLM and BBC (Bill Barrett Corp.) -- is pure science and the chips are going to fall where they will."

Keith Kloor is a New York-based freelance writer and currently a Ted Scripps Fellow at the Center for Environmental Journalism, University of Colorado.