Last Wednesday morning, in a remote valley of the rugged Trinity Mountains, a couple dozen volunteers pulled their cars onto the dusty gravel road that dead-ends between the South Fork Trinity River and the Hyampom Airport. "Airport" may be too strong. It's a landing strip, 1,250-feet high, in the middle of the Trinity National Forest. Hyampom itself is about as remote a community as you'll find (or attempt to find) in the continental United States. Accessible only by twisty mountain roads, the isolated hamlet (pop. 241) contains little more than a general store, post office, K-8 school and two bars.

The volunteers — mostly from environmental groups, along with a couple of journalists — had come hundreds of miles, from Garberville, Arcata, Fresno and beyond, to help the U.S. Forest Service clean up a nearby marijuana grow site that had been busted and abandoned in August. They climbed out of their cars and stood blinking and stretching in the brisk November sunshine. After brief introductions, they consolidated into the sturdier, four-wheel-drive vehicles and caravanned to the nearby staging area, a wide spot on the southern river bar.

There they met up with employees of the U.S. Forest Service, the state Department of Fish & Wildlife, scientists, more volunteers and reporters — and, off by themselves, a squadron of soldiers from the U.S. Army National Guard, who stood wide-legged and stone-faced in camouflage fatigues and utility vests, handguns holstered to their thighs. A hundred yards away, a helicopter sat perched on the rocky riverbed, its rounded windows glinting in the sun.

The day's collaborative cleanup event was the product of an ongoing partnership between the Forest Service and the High Sierra Volunteer Trail Crew, a Fresno-based nonprofit dedicated to preserving and restoring public lands. The group's former executive director, 57-year-old Shane Krogen, helped establish the partnership, which focuses on marijuana site cleanups, in 2005. Krogen was on a cleanup mission in September when, for reasons still being investigated, he fell out of a helicopter and dropped 50 feet to his death.

On the river bar, the group's new executive director, Rick Fleming, and its volunteer coordinator, Bruce Hilbach-Barger, gathered the volunteers for a safety briefing. "The activity today is dangerous, physical and demanding," Fleming said. Beware of wild animals, he added — this is black bear and mountain lion country. Also beware of booby traps set by growers. They're usually aimed at animals — baited fishhooks, for example — but there was that time in the Sierra when they found a shotgun hooked to a tripwire.

Also look out for blades and unsprung rat traps. Keep an eye out for marijuana drying lines, which are often strung at head-height. And don't touch any unknown substance: It could be poison. An aluminum canister with a flag on it is probably Weevil-Cide. Other materials documented at the site include strychnine, rodenticide and an unknown pink substance repackaged in old bleach bottles. They suspect it's carbofuran, an extremely toxic and systemic insecticide.

"It's nasty stuff," Hilbach-Barger said. Marketed under the name Furadan, carbofuran is banned in the U.S. on all crops grown for human consumption. It's still sold (with a skull-and-crossbones label) in Mexico and imported across the border, though it's manufactured domestically. A single grain will kill a bird. A quarter teaspoon can kill a black bear or a human. And it's being used in marijuana production.

"Somebody's smoking some incredibly bad stuff," one volunteer quipped.

Like thousands of other grow sites hiding in the sensitive habitat of Northern California and beyond, this illicit, industrial-scale marijuana grow (law enforcement eradicated between 5,000 and 6,000 plants, putting it on the small side of average) was an environmental nightmare. The men who ran it dammed creeks, ran miles of water line and siphoned out thousands of gallons to irrigate their crops. They cleared trails and built reservoirs, destabilizing steep hillsides. And they scattered tons of dry fertilizer, gallons of liquid concentrated fertilizer, mountains of trash and an array of poisonous chemicals into a habitat that's home to a diverse range of wildlife, including the federally endangered northern spotted owl and the Pacific fisher, a member of the weasel family that's a candidate for federal protection.

Forest Service officials figure the operation, which was on public land, employed five or six men, but just one was arrested, a 21-year-old Mexican immigrant named Andres Montes-Deoca who's being held without bail on Immigration and Customs Enforcement hold, according to the Humboldt County Sheriff's office.

In July, a dead fisher was found at a marijuana grow site near Willow Creek. A necropsy revealed that it died from internal hemorrhaging caused by Methomyl, a toxic insecticide that had been laced into a hotdog and set out as bait.

As prohibition continues to fuel high profits and drive production into remote public lands (often exploiting cheap immigrant labor), scientists have just begun to study the environmental impacts of these industrial marijuana grow operations. As they examine the myriad routes that toxins may take through the ecosystem, they've become increasingly concerned with what U.C. Davis researcher and local nonprofit leader Dr. Mourad Gabriel calls the "potential cascading of risk" — a creeping environmental catastrophe whose scope we may not fathom for years.

 

From the river bar, the reporters and multiagency cleanup crew (now more than 50 people), piled into the biggest of the big vehicles and caravanned another 20 minutes up a dirt road. In the harsh, late-morning sunbeams, the road dust billowed in front of the windshields, obscuring visibility on the mountain switchbacks. Up top, the trailhead was marked with an old tube TV lying face-down with bullet holes blown through its plastic casing.

Soldiers and volunteers, the latter wearing mandatory hard hats, long sleeves and work gloves, scrabbled over a line of uprooted tree stumps and continued down a side-slope path into the forest. Before long, they started seeing trash — empty fertilizer bags, aluminum cans, Styrofoam soup cups. Farther along, more trash: an empty jug of Ortho's Bug-Geta Plus, liquor bottles, ammonium sulfate bags, egg cartons, bleach bottles, tuna cans. An entire outfit — black jeans, a striped green thermal and a down jacket — lay among the twigs and pine cones, as if the man inside simply evaporated.

Another 50 yards down the path, the group came to the main campsite, where a rickety fort had been built out of tree branches and twine, with a brown plastic tarp roped to surrounding trees as a canopy. The leafy ground surrounding the fort was thick with garbage, which had clearly been ransacked by at least one bear. A researcher who had been to the site previously noted a Clorox bottle that had been half full of the mysterious pink substance. Now it was empty and riddled with what looked like bear-teeth holes.

The garbage revealed a lot about the day-to-day lives of the workers who lived here, from their diet (Maruchan instant noodles, orange Shasta, canned tomato sauce) to their routines (sleeping bags, propane tanks, a camp stove) to, most obviously, their jobs (stacks and stacks of plastic pots and trays, full bags of FoxFarm potting soil, backpack-style fertilizer sprayers, etc.).

Media representatives, including an NBC camera crew, Mother Jones writer Josh Harkinson and others, spent a few minutes snapping photos and conducting interviews with scientists and volunteers. And then it was time to work. The group divided into work crews of four to six people and split up, following trash trails deeper into the woods and pulling out black PVC flex pipe, miles of which had been run from nearby creeks and streams and spread out among the site's five trail-connected grow areas.

One crew included Hilbach-Barger, a reflective-yet-tough older hippie-type with a frizzy white beard, along with a young freelance reporter for the Trinity Journal, Northcoast Environmental Center Executive Director Dan Ehresman and this reporter. We spent the next three hours traversing the mountainside, stuffing trash into giant orange bags, tearing down jerry-rigged check dams and dismantling the site's elaborate irrigation system.

Around 1 p.m. we came across a clearing where a black pipe lay in the dirt, flowing like a garden hose. We followed the pipe up a steep creek bed, ducking under tree limbs and struggling for footing on the leaf-strewn slopes. Finally we came to the source. The pipe was submerged in a small pool behind a log-and-mud check dam. At the end of the line, adhered with crisscrossed electrical tape, was a perforated tin can covered in a thin fabric, which sat gurgling and sputtering in the pool like a thirsty animal.

Hilbach-Barger and I pulled up a corner of the black plastic that lined the pool and pierced its pregnant belly with a shovel blade. We scooped out the sludge and, with considerable tugging and mud-suck pulling, managed to excavate the plastic sheet. After dismantling the dam, Hilbach-Barger stood up and breathed deep.

"We just liberated a stream," he said.

Like the other crews scattered across the mountain slope, we dragged and heaved our loads of trash to helicopter pickup sites. The plastic waterline we coiled into big hoops and secured with duct tape. We pulled huge plastic tarps from dug-out reservoirs and folded them into puffy rectangles. And we piled everything into giant nets, which National Guardsmen helped cinch up and hook to the 150-foot cable dangling from the thundering helicopter above.

 

The politics surrounding marijuana tend to complicate matters when it comes to studying the environmental impacts of illegal grow operations such as this one, according to Gabriel. A Blue Lake resident and president of the nonprofit Integral Ecology Research Center, Gabriel is also a senior wildlife ecologist and research scientist at U.C. Davis' School of Veterinary Medicine.

He's convinced that policymakers — and the public — need sound scientific data on the damage being done by this outlaw industry, but getting cooperation has been a challenge. His nonprofit has frequently been shot down for research grants, with most potential funders saying his chosen subject is more of a moral or ethical issue than an environmental one and should therefore be addressed by political scientists.

"It took us about two years to convince people this is an environmental issue," Gabriel said.

Others, meanwhile, have accused him of "greenwashing" the data — that is, skewing results to meet a political agenda. "People say, 'Dr. Gabriel is a stooge for law enforcement,'" he said. That's part of the reason why Gabriel helped to organize last week's media/volunteer event, so people could see the impacts firsthand.

"There is a political discussion" to be had about marijuana, Gabriel said, "but there also needs to be an environmental discussion."

The more he looks into the potential impacts of these grows, the more ominous the situation seems. Not only are there direct effects of poison — like the lethal hotdog eaten by a fisher — but there's also secondary exposure to consider.

"For example, rat poison can stay in the soil," Gabriel said. "Insects can be exposed and have it sequestered in their tissue. No one has done experiments to see, if bird or snail eats that earthworm, will they be exposed? We already know that if a rodent consumed poison and a bobcat or fisher consumed the rodent, they will be exposed."

The same transmission can occur with raptors eating carrion or, potentially, a human hunter who consumes the flesh of a poisoned bear, Gabriel said. He and his fellow researchers have just begun testing the muscles, liver and other tissues of game species found in remote grow sites to see if they've been exposed.

"That should be really alarming to folks, that we now have contamination in an area where we would have never expected these toxicants to be," Gabriel said.

Even more concerning than the sites that are found are those that aren't. Toxins are often stored in weather-resistant plastic containers, and it can take years for them to degrade or be found. In addition to the spotted owl and fisher, the local habitat is home to aquatic species such as steelhead trout, coho and Chinook salmon; avian species such as the pileated woodpecker and northern goshawk; amphibians such as the foothill yellow-legged frog and southern torrent salamander; as well as mammals such as the gray fox, black bear and mountain lion. And in addition to poison contamination, the ecosystem can be damaged through soil erosion, water diversion, fertilizers that spawn toxic algal blooms and more.

"We're trying to create this laundry list, but the more and more we talk to other experts, the laundry list just keeps on growing," Gabriel said.

 

On Friday, the U.S. Forest Service and Gabriel's Integral Ecology Research Center released a synopsis of the environmental impacts at the Hyampom grow site: Roughly 8,000 pounds of trash was removed, along with 4,172 pounds of soluble fertilizer and 7 1/2 gallons of liquid fertilizer; 12 dams (average water diversion: 600 gallons) were deconstructed along with five reservoirs (average water diversion: 1,500 gallons); four natural springs that had been unearthed and tapped were restored; and at least eight types of toxicants were identified and removed.

"Then you think to yourself, they just cleaned up five sites in Hoopa that have the same type of impact," Gabriel said. "The Humboldt County Sheriff's Office just did [a cleanup at] Brush Mountain. They found the dead fisher at a site in Orleans. That's just a handful of what they could address in 2013, and that's only within the county I live in."

Toward the end of our cleanup day, as our crew waited for the helicopter pilot to come pick up our three big nets full of trash, Ehresman, of the Northcoast Environmental Center, peered into a nearby ravine and saw a blue tarp — part of a reservoir we hadn't yet seen, with water lines continuing down the hill to a separate grow site below. He and Hilbach-Barger hiked down and took it apart, but the grow down the hill would have to wait for another day, another cleanup crew.

As we hiked back up the hill in the late-afternoon sun, we found another reservoir that had been missed. Hilbach-Barger radioed up to the base: "We just found a two-to-three-thousand-gallon reservoir. Should we dismantle?" We did, pulling out the big blue tarp, dismantling the walls branch by branch and hauling the pipes and trash back down to the pickup site. Farther up there was yet another overlooked reservoir — a big one, surrounded by trash — but by now it was getting late. The helicopter pilot was running out of time, much to the frustration of the soldiers, who openly mocked him for being overly cautious, failing to pick up nets because the clearing was too small or the load was off balance. Pathetic, the soldiers grumbled. Exhausted and running out of daylight, we left the structure behind, grabbed as much trash as we could and continued hiking.

Eventually we reached the site of the growers' camp, which had been completely torn down and cleaned up.

"Amazing," Hilbach-Barger said. "It looks like a forest again." He surveyed the bare, dusty ground and piles of discarded logs. "But it's got some recovery to do," he added.

On the phone a couple days later, Gabriel said his main concern is that this activity is happening on public lands. "That really has created a fire in me to start focusing on potential collaborations to try to address this and get as much data out there as possible. ... I cannot sit on my idle hands waiting to address this."

The hands building and maintaining these grow operations clearly won't remain idle either. Nor will the wildlife living among them.