Cleaning the Creek

Tailings are the mess left by mining, what's left after ore is broken into rock or crushed into powder and the metal has been extracted. It has no earthly use, but it has to go someplace, and so the rock gets dumped into unsightly toxic piles and the powder gets sprayed into terraces that resemble Mayan pyramids.

The BHP Copper Pinto Valley mine tailings scar a long ridge five miles west of Miami, Arizona. Anyone who has driven Route 60 from Phoenix to Globe has seen the flesh-colored flat spots on the otherwise dark and craggy skyline. They are called "impoundments" or "ponds" or "dams," because the tailings material is sprayed onto them wet. And though the outside dries into something that looks like dirt, the inside stays wet and viscous like an underdone omelet. Mining folk call that material "plastic slimes," and it makes an unstable base for anything on top of it.

On October 22, 1997, one of the BHP tailings impoundments blew out under pressure from rocky debris loaded on top of it. More than 317,000 cubic yards of mining waste the consistency of toothpaste squeezed from the heap and flowed into Pinto Creek below, filling it rim to rim, 70 feet across and 42 feet deep in some places for three quarters of a mile. Gray liquid oozed and ran from the muck, turning another three-quarter-mile reach downstream into an environmental nightmare.

As if Pinto Creek didn't already have problems.
In 1993, heavy rains had flooded the same impoundment and washed tons of tailings down Pinto Creek, roughly 20 miles to Roosevelt Lake. And for six years, environmentalists had been fighting the imminent Carlota Mine, which will be dug in the creek bed immediately upstream from the October spill.

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For three years running, the environmental group American Rivers has placed Pinto Creek high on its list of the nation's most endangered rivers. The U.S. Forest Service nominated its lower reaches for "wild and scenic river" status.

But the mile-and-a-half tailings plug near the creek's source might have destroyed nearly everything wild and scenic about Pinto Creek if the weather had been different--or if BHP, the company responsible for the spill, hadn't immediately opened its wallet.

BHP, a gigantic international mining corporation headquartered in Australia, by now has sunk more than $20 million into a cleanup that may serve as a model for cleaning up future mining disasters. A state mine inspector speculated that the cost may reach $30 million before it's done.

The accident occurred because of a practice that the same mine inspector later called "stupid."

The impoundments were built in the 1970s and 1980s by Magma Copper, the mine's previous owner. There had been no new tailings placed there since 1987.

In the fall of 1996, however, BHP decided to use the tops of impoundments as dumps for another sort of mine waste. Copper ore lies deep underground, and the earth has to be stripped away to get at it. The "overburden" then has to be hauled off. BHP, with the approval of an outside engineering consulting firm, was dumping the overburden on top of the tailings impoundments. Then, after they'd placed as much as they could, they would have graded the rock and revegetated it, making the tailings scars less visible from the road.

Workers had already piled a layer of rock and fill 50 feet deep on the impoundment and were just starting to add a second 50-foot layer when it broke. The soft center simply could not support the weight of the rock dump.

"You put a 10-tiered wedding cake on a base of Jell-O, then something's going to give," says Bill Hawes, assistant state mine inspector.

"I would never want to do anything on a tailings pond more than put a few feet of waste to prevent dust from blowing," Hawes continues. "The next mine code that comes out will forbid that practice from happening."

During the course of the year in which BHP was piling rock on the tailings dam, it suffered many minor fractures, according to one worker. The ground would split open in cracks up to 20 feet across and 100 feet long, exposing the slimes beneath the hardened surface. Engineers checked it every day for stability. No one expected it to blow out completely.

Frank Candelaria was at the highest point of the rock dump on top of the Pinto Valley tailings impoundment when the earth gave way.

He sat behind the wheel of a 190-ton truck, hauling a load across the upper tier, which was about the size of a football field.

"I looked down and all of a sudden it's the Twilight Zone," he says.
The ground in front of him had cracked like thin ice, with fissures silently spiderwebbing out beneath his truck "like one of them earthquake movies."  

A wall of crushed rock as plum and level as if built by a mason seemed to shoot up on his right side. In fact, Candelaria and his truck were falling, riding the entire tier like a giant elevator. It dropped 30 feet until it was level with the top of the lower tier.

Time stopped for an instant. Candelaria still hadn't realized what was happening.

After an interminable fraction of a second, the ground beneath the truck started to move again, this time tilting, sliding down and away from the wall towering above it. For the first time Candelaria felt the movement, a sickening sensation he likened to a boat pushing away from a dock. He looked up.

"All of a sudden the mountain that was on my side starts rolling like surf," he says wondrously. "First I can see it crawling up the side of the truck and then rolling over and across the top."

The windshield and the passenger-side window were buried. Candelaria looked left out of the driver's window.

"That's when I knew I was in deep shit," he says. "I'm level with the damn tailings, and it's like a damn wave pumping down the side of the canyon."

Candelaria got out of his truck and "hiked out of that mother."
If he escaped unharmed, the delicate riparian area below was not so fortunate.

For the next 30 minutes, the slime rolled over itself like lava, down the hillside from mine property into the Tonto National Forest. After traveling a quarter mile and descending 400 vertical feet, it reached Pinto Creek and flowed upstream as far as gravity would allow, then turned downstream. Beneath the chute it was 42 feet deep; at its farthest point, three quarters of a mile downstream, it was eight feet deep, and then it stopped abruptly.

Pinto Creek is an intermittent stream. Parts of it run year-round; parts don't. The spill occurred on a dry stretch during a dry season. If the stream had been running top to bottom, the flow would have carried the tailings farther downstream. Although the tailings material is not particularly toxic, it has such fine particles that it could suffocate any plant or animal life in the water.

After the tailings stopped, slimy liquid poured out of the mass and coated everything downstream--the dry streambed interspersed with perennial pools--for another three quarters of a mile.

Russell Haughey, a habitat biologist from the Arizona Game and Fish Department, walked the length of the spill in the days following the accident.

"Up above, it was the consistency of drywall mud," he says. "Farther down, there was water flowing, but there were a lot of fine [particles] and it would form the consistency of pudding."

Haughey found some dead fish atop the pudding; others seemed to be swimming in it. Turtles and lizards skittered on the surface. Haughey found prints where larger mammals had struggled through.

In its earliest reports, the U.S. Forest Service estimated that the spill would be cleaned up within a month. It was not to be.

Nonetheless, BHP moved quickly. The company brought in its own top talent and recruited from its extensive properties the world over. It transferred one of its best engineers, Mahmoud Yasin, from a mine in Peru because of his earth-moving experience. It asked the Forest Service and the other agencies to refer the best restoration ecologists available and then hired them. It brought in an army of about 200 workers, put them on earth movers and handed them shovels and buckets and started them all digging.

In early April, Pinto Creek bore an eerie resemblance to the construction on the northernmost stretches of the Squaw Peak Parkway. Bulldozers, earth movers, haul trucks, dwarfed by the canyon walls, rolled along the canyon bottom where the stream once ran.

There had been no question on the part of the mine company officials or on the part of the biologists and enforcement specialists of the state and federal regulatory agencies that BHP was going to have to clean up its mess.

"We have a statutory responsibility, but we have a moral and ethical responsibility to respond quickly and decisively to see that this thing is contained as soon as possible," says Dee Durazo, the mine's general manager.

"Unlike a lot of mining companies, I think they're doing a good job," says James Hillenbrand, an enforcement officer for the U.S. Environmental Protection Agency. "They faced it full on."

But no one had ever undertaken a cleanup of this nature. Countless tons of semisolid material had to be hauled out of an inaccessible canyon, and then a sensitive riparian ecosystem had to be restored.  

The first challenge was to contain the spill, and so the engineers built temporary dams called gabions at the bottom of the semisolid mass and at the farthest point of contaminated stream water, and then installed pumps and pipe so that they could pump all of the tainted water out of the streambed and up to the mine property.

In order to keep winter and spring flows from hindering the cleanup and carrying any tailings material downstream, they built a dam 53 feet high and 500 feet wide upstream from the spill. The water that backed up behind it was then pumped through flexible plastic pipe that ran up over the hillside and dumped back into the creek two miles downstream. A 36-inch-thick pipe ran through the canyon alongside the tailings, a hedge against heavy rains, in case water had to be released quickly. The pumps behind the dam could move 11,000 gallons per minute.

"It was living on the edge for a long time, and everybody watched the incoming storms like hawks," says Stu Herkenhoff, a minerals specialist for the Forest Service.

To keep the heavy earth-moving machinery from foundering in the tailings, the engineers had to spread a layer of rock over it to serve as a road. Those machines have worked constantly since last fall, digging out and hauling away debris.

Below the semisolid mass, workers dug in the streambed with shovels and buckets to cart out pockets of tailings, and then they released water from the dam through the 36-inch pipe, literally washed the lower three quarters of a mile, and then captured the water downstream and pumped it up to the mine property to use as industrial water. Miraculously, that lower reach of water now shows little sign of the slimes that coated the banks and the river rocks.

By mid-April, the upper reaches had been rid of most of their heavy material. The embankments had been scoured and graded, and a revegetation consultant had sprayed them with a mixture of mulch and seed and compost.

"I was pretty impressed with what they've done with the mess they had," says Dan James of the consulting firm Western Sere, which handled the revegetation.

He proceeded to fashion a seed list of native grasses, forbs, wildflowers and woody plants.

"If you walk the hillsides, they're just loaded with species," James says. "We put in as many species as we could get within reason in the seed mix. I think we used 20 or 25 species."

The jobs that remained were to pull out the rock that had been laid as a road for the heavy equipment and then to scrape tailings down to the stream bottom's river rock. The larger boulders would be rearranged to approximate the falls and riffle pools of the original stream. The entire stream bottom would have to be washed. Finally, the workers will plant willows and other riparian trees.

"Our goal is the end of June," says Evelyn Bingham, BHP's environmental engineer.

When the EPA and the state Department of Environmental Quality are satisfied with the creek's water quality, the gabions can be removed. The big dam above will remain until after the summer monsoons to make sure that the new stream contours and the nascent vegetation are not washed away.

What is the future of Pinto Creek?
Don't count on a benevolent environment. For all its good work and responsible actions, BHP was forced to respond properly to the Pinto disaster because it had a statutory gun to its head. And it turned over its wallet smilingly, knowing that it was insured against such liabilities. No matter how well BHP succeeds in repairing its mile-and-a-half stretch of the creek, Pinto Creek will be changed forever, and because of the nature of mining, there is no guarantee that other disasters won't occur. Considering that a reach of the creek just upstream from the cleanup will soon have a new strip mine in it, the odds of Pinto Creek's survival diminish even more.

The 1993 flood that washed tailings out of the same impoundment was grounds for a federal lawsuit against Magma Copper, which had built and operated the impoundment. When BHP absorbed Magma in 1996, it took responsibility for the consent decree that Magma had signed with the EPA and the Arizona Department of Environmental Quality. Any further discharges from the impoundment would violate that consent decree. BHP is now paying $3,000 a day as the tailings are being removed, the fine stipulated in the consent decree.

Much of the $20 million that BHP has already spent to clean up the creek may be reimbursed by insurance.  

"We're working with our insurance carriers and their representatives right now," says General Manager Dee Durazo. "It has yet to be determined how much will be covered and how much will not be covered."

Furthermore, BHP may be able to sue the Tucson firm that helped engineer the rock dumps to recover more money.

"I don't know if we're going to file a claim [against the engineering firm]," Durazo says. Managers of the engineering firm chose not to talk to New Times.

Incidentally, BHP has laid off 400-some workers because of the low price of copper in the marketplace.

The environmental damage to Pinto Creek is more difficult to gauge than the financial damage to BHP.

Before the 1993 flood, the creek was habitat for five species of fish; after the spill, it had just three, though it is impossible to determine that the die-offs are directly related to the spill.

The October spill took place when the stream was dry and consequently did not move very far. And its components are relatively nontoxic and do not have the kind of half-life that some chemical spills would have.

But regardless of how environmentally ethical BHP may claim to be, mining is hazardous to the environment.

BHP is also party to a $100 million federal court settlement last August with two other Arizona mining companies to clean up mining spills in Pinal Creek, which runs east of Pinto Creek. Admittedly, that is also a mess that BHP inherited from Magma. Last November, however, a pipe burst at another BHP facility near Globe, spilling 72,000 gallons of tailings into two washes that empty into Pinal Creek.

And if Pinto Creek isn't already reeling enough from the ecological disturbances of the October spill, it will be disturbed even more when the Carlota mine is built just upstream.

In 1995, the EPA gave the Carlota Mine's draft environmental impact statement its lowest possible rating, meaning that the agency found both the plan and the document that described it to be inadequate. Local environmentalists, the Forest Service and the EPA raised so many issues about the draft EIS that Cambior, the Canadian mining company that owns the rights to Carlota, was forced back to the drawing board ("No Miner Consideration," September 7, 1995). Three years and $60 million later, the Carlota Mine is one federal permit away from reality.

Carlota originally planned to reroute Pinto Creek into a concrete chute around the mine's main pit. The current plan will require Carlota to carve a shelf out of a mountainside, gouge a trough in it, spray soil cement on the bottom and then dump six to eight feet of the creek's original sediment in it.

"It's obviously different [from the original creek]," says the Forest Service's Paul Stewart. "The question is how well you can get it back to something that serves as habitat as reasonably close as you can get it."

It will look terrible, but trying to make an aesthetically pleasing stream that runs between a mine pit and a tailings impoundment is like putting makeup on a pig.

"You can't stop a mine because of aesthetics in the United States," says the EPA's James Hillenbrand, "unless you get the president involved like they did in Yellowstone."

Arizona congressmen have gotten involved, but on the side of the miners, beating the jobs drum and failing to see the irony in elected U.S. representatives trying to give U.S. lands to a Canadian company.

Congressman J.D. Hayworth convened a "mining summit" in early April. In his initial letters to constituents, Hayworth claimed he would bring together mining representatives, city, state and federal officials and environmentalists. But when the invitations went out, the environmentalists were forgotten.

"When I called J.D.'s office to find out the details, they said that environmentalists weren't invited and that basically I wasn't welcome to show up," says Sandy Bahr of the Sierra Club.

Bahr went anyway and reports that Hayworth's main concerns were over how long it was taking Carlota to secure all of the necessary federal permits.

"I think they were trying to intimidate us," the EPA's Laura Gentile says of Hayworth and his mining constituents. "Look in the mirror, fellows: You've had major spills. If you would start giving us projects that are better designed, it would go a lot faster."

Last December, an environmental group that calls itself Citizens for the Protection of Powers Gulch filed suit against the U.S. Forest Service for approving the Carlota mining plan and asked for an injunction against the mine, citing water quality and quality-of-life issues and pointing to the BHP spill as evidence of the environmental damage that mining can cause.  

But the BHP spill may be cleaned up too quickly to remain much of an example of the environmental irresponsibilities of mining.

By last week, the water had been drawn down behind the big dam built to keep Pinto Creek out of its recovering bed, and the 36-inch pipe that ran the length of the spill had been removed.

Green shoots blanketed the revegetated gulley that the spill had followed on its way downhill from the tailings dam to the stream.

Earth-moving equipment with shovels on telescoping arms had started pulling out the last of the tailings material from the northernmost reaches of the spill. They were working their way out like painters on a floor painting their way toward the door.

Workmen with shovels and hand trowels dug tailings out of the canyon walls.
Backhoes had positioned big boulders in lines behind which sediment can build up when the stream finally flows freely.

At the far end of the canyon, a man in rubber boots trained a firehose on the ground. Under its stream, fine stones and sands, the reds and browns of natural alluvium, the real streambed, were miraculously reappearing, and the sandy gray tailings slime was washing down into a pool to be pumped away forever.

Contact Michael Kiefer at his online address:

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