Why is extracting copper bad for the environment

Run-of-the-mill pipeline leaks and seepage from underground mine sites are also serious vectors for contamination as shown by Dr. Tom Myers, a hydrology consultant who has studied the preliminary plans for mines proposed near the Boundary Waters. The Twin Metals pre-feasibility study calls for a massive network of pipelines to dispose of sulfide-, metal- and chemical- laden tailings.

Half of the tailings would be piped from the 1,acre concentrator facility on the shore of Birch Lake; the other half would be piped back underground. In addition to tailings dam failures and pipeline leaks, sulfide-ore copper mines can pollute through seepage from underground pits and surface waste rock and sulfide-bearing ore. These pollution vectors are hard to detect and difficult to fix.

By exposing sulfides minerals in the pit walls to oxygen and water, they are able to produce acid mine drainage. Cracks in the bedrock connecting the underground mine to groundwater can then transmit the generated acid mine drainage to streams, lakes, and some wetlands. It is reasonable to expect that underground seepage of pollutants from the Spruce Road deposit owned by Twin Metals would eventually penetrate the Boundary Waters, according to modeling conducted by Dr.

Any surface storage of waste rock, tailings and sulfide-bearing ore also creates the opportunity for water bearing acid, heavy metals, or sulfates to seep into groundwater despite engineered liners designed to contain them.

All liners leak to some extent, and no liner has been tested over the decades and centuries required to permanently protect the Boundary Waters from pollution from sulfide-ore copper mining. In light of the combined facts that sulfide-ore copper mining on the edge of the Boundary Waters would likely contaminate the Boundary Waters and surrounding lakes, rivers and streams, and that the industry has a poor track record of preventing water quality impacts, it is clear that sulfide-ore copper mining would be too risky for the Boundary Waters Canoe Area Wilderness and Voyageurs National Park.

This specific spot in the northern Santa Ritas also provides wildlife corridors to the Empire Mountains, Whetstones, and Rincons to the east and north. Here they honor their ancestors, some of whom are buried in the area, and gather medicinal plants. A couple miles to the northeast, Hudbay plans to dig a conical pit in the Earth measuring a mile wide and up to 2, feet deep—deep enough to fit two Empire State Buildings, one atop the other.

The plan entails blasting out and excavating million tons of ore containing copper, and molybdenum, and dumping 1.

In all, the mine would take up 4, acres of public land, administered by the Forest Service, and its borders would stretch within hurling distance from where I stand. These tailings would cover miles of streams that lead into Davison Canyon, to the northeast. After excavation, the ore would be crushed and washed with water and reagents to concentrate the copper and molybdenum. Next it would be trucked out to a smelter, likely in another country. Trucks would haul an estimated 50 daily shipments of copper concentrate down the adjacent two-lane highway, scenic state route Much of the water for this process would be pumped from another aquifer, to the west of the Santa Ritas.

Starting near the town of Sahuarita, Hudbay would build a pipeline to stretch over the mountains, along with eight miles of access roads, lights, and electrical lines. The pit would puncture the aquifer and drain water into it, creating a pit lake reversing the normal flow from the aquifer to springs and creeks.

But the lake wouldn't remain static: It would evaporate water quickly, at a rate up to gallons per minute, according to the U.

After the life of the mine, estimated at 19 years, the pit lake would form, enlarge, and keep evaporating groundwater in perpetuity. The lake would eventually grow to a surface area of acres three-times the size of the Superdome , containing about as much water as Tucson uses each year. But continual evaporation and refill would concentrate metals and other chemicals. Years in the future this would create a toxic environment for many animals, exceeding chronic exposure standards for cadmium, copper, zinc, and selenium, the EIS notes.

That could pinch Tucson, which currently gets its water from the Colorado River , though that resource is politically fraught and unstable. Mine runoff would impact water quality downstream, although models differ as to how much, Meixner says. But a lower water table could cause some springs and creeks to dry, rare trees and plants to die, and wildlife that depend on them to move or perish. The Bureau of Land Management, which is in charge of the 42,acre Las Cienegas National Conservation Area east of the mine site, has repeatedly warned the Forest Service that Rosemont would likely cause parts of the area to go dry part of the year.

Even a few dry days in Cienega Creek could be disastrous for wildlife like the topminnow. Ditto for the Chiricahua leopard frog. The population at Las Cienegas seems to have a tolerance to chytrid, the fungus that is devastating amphibians worldwide , says Randy Serraglio, a conservation advocate for the Tucson-based Center for Biological Diversity.

During its planned year life, it would provide jobs for an average of about people, Brubacher says, paying wages twice the median in Pima County. It would inject billions into the local economy, he adds. The mine is supported by Republican governor Doug Ducey, and the mining industry remains powerful in Arizona, which produces more copper than any other state.

Rosemont would be one of the biggest in the U. Though none of these mines have come online since , two are planned to begin construction later this year: One in Nevada, and another, the Gunnison mine , about 45 miles to the northeast near the Dragoon Mountains— where another Apache chief, Cochise , surrendered to the U. Army nearly years ago. Many in the area take issue with a foreign company digging up American resources, using scarce desert water, and leaving behind a mess, Serraglio says.

The mine would, of course, drastically change the landscape. What is now a series of green hills would become a pit lake and a vast mound of waste rock. Besides the impacts on animals and water, it would also produce near-constant noise and light while the mine operates, in an area famous for nights both quiet minus the howling of coyotes and the hooting of owls and dark, which makes it a prime spot for astronomy.

This permitting process, which is overseen by the Environmental Protection Agency, is meant to make large projects like mines comply with the Clean Water Act. But in November , Donald Trump was elected president. Bernhardt, now Interior secretary, was a lobbyist for Hudbay from through , and a consultant to them for more than a year thereafter.

The final decision was delayed for two years. The only major necessary permit remaining, from the Forest Service, came through weeks later, in late March. The service administers the public land where much of the mine would sit.

Many pres tailings impoundments did not have such barriers. The infiltration of surface water into tailings can be prevented by using reclamation methods that facilitate runoff rather than ponding of surface waters. If not prevented or controlled , the acidic and metal-bearing waters from tailings can impact stream habitats and groundwater. At some sites, gas and particulate emissions that were released to the atmosphere from historical smelting operations have been a source of human health concerns and environmental impacts.

Recognizing the importance of minimizing and mitigating this impact, modern smelters use processes that drastically reduce particulate and sulfur dioxide emissions. Barren areas near smelting operations have been an enduring environmental impact of historical smelting. Some impacted areas that have existed for decades are now beginning to recover.

In some cases, the emissions from older metal smelters may have affected human health. For example, elevated levels of lead in blood have been measured in residents of some communities located near lead-zinc smelters during their operation. Today, smelting operations, combined with environmental controls, are implemented to prevent potential environmental and health issues related to emissions.

Public Safety Old mining sites are inherently interesting to people, but potentially dangerous as well. They may have surface pits, exposed or hidden entrances to underground workings, or old intriguing buildings. Because an unexpected collapse can occur without warning, such areas usually are identified and should be avoided. When modern mines are closed, mine owners mitigate such hazards by closing off mine workings, regrading and decreasing the steep slopes of surface excavations, and salvaging or demolishing buildings and facilities.

In some states where old mining areas are common, such as Colorado and Nevada, current mine owners, government agencies, or other interested parties may undertake reclamation and safety mitigation projects that address hazards at these sites. At a minimum, these programs identify hazards, install warning and no trespass signs, and fence off dangerous areas.

The closing of entrances to old underground workings may also be done as a part of these efforts. Some abandoned mine workings have become important habitats for bat colonies. Closure of mine openings can be designed to allow the bats continued access and protection. This practice is especially valuable for endangered bat species. Because many old mine sites may not be safe, the casual visitor to such sites is cautioned to exercise care and avoid entering them. Skip to main content.

PDF version. Concerns include: Physical disturbances to the landscape Soil and water contamination Air contamination Public safety Physical Disturbances The largest physical disturbances at a mine site are the actual mine workings, such as open pits and the associated waste rock disposal areas.

Soil and Water Contamination from Waste Rock and Tailings Mobilization of metals in waste rock Waste rock disposal areas are usually located as close to the mine as possible to minimize haulage costs. Acid rock drainage from waste rock Although the character of waste rock varies with the type of ore, many waste rocks contain sulfide minerals associated with metals, such as lead, zinc, copper, silver, or cadmium. Acid seepage from tailings Tailings produced from the milling of sulfide ores — primarily copper, lead, and zinc ores — may have concentrations of pyrite that are greater than those common in waste rock.

Air Contamination At some sites, gas and particulate emissions that were released to the atmosphere from historical smelting operations have been a source of human health concerns and environmental impacts.