Pebble Mine: The biggest environmental threat in Alaska

Everyone has heard about ANWR.*  It is so well known that I do not have spell out the acronym. Ever heard of the Pebble Mine Project?  Probably not. The major environmental organizations have done an extremely poor job of publicizing this disaster in the making. Pebble Mine is worse than anything the oil thugs want to do in ANWR and it is in the permitting stage, making it a critical issue in terms of time and public awareness. Please join me for an introduction to the proposed Pebble Mine Project.


*Arctic National Wildlife Refuge

What is the Pebble Mine Project?

It is a plan to build one of the world’s largest copper and gold mines on state-owned land in the Bristol Bay area of southwestern Alaska. The current proposal calls for two mining operations. Pebble West would be the largest open-pit mine in North America. The proposed pit would be about 2 miles wide and over 2 thousand feet deep. It would produce copper, gold, and molybdenum from low grade, high sulfur ores. Pebble East would be an underground mining operation to extract somewhat higher grade ore (but still under 5% relative to waste rock). The operation will be a joint venture of  the Northern Dynasty Minerals (a newly created mining partnership headquartered in Canada) and Anglo American (an international mining conglomerate headquartered in the UK).

Here is the description from the Alaska Department of Natural Resources:

The Pebble Project is a copper-gold-molybdenum porphyry deposit that, as of May-2007,  is in the advanced exploration stage.  The project is located in the Bristol Bay Region of southwest Alaska, approximately 17 miles northwest of the community of Iliamna, and is operated by Northern Dynasty Mines Inc. (NDM).

Pebble consists of two contiguous deposits.  Pebble West is a near surface resource of approximately 4.1 billion metric tons that, if developed, would likely be mined by conventional open-pit mining techniques.  Pebble East is significantly deeper than Pebble West and contains generally higher grade ore.  Its size is currently estimated at 3.4 billion metric tons.  If developed, Pebble East would probably be mined via bulk tonnage underground mining methods.

NDM is currently conducting a deep drilling program to further explore the Pebble East Deposit and upgrade its resource classification.  The company has stated that it expects to finalize its proposed mine development plan and apply for development permits no sooner than late 2008 or 2009.


Pebble Mine is a large plunder-and-pollute operation that will threaten water, wildlife, and way of life for Alaskan natives of the environmentally sensitive Bristol Bay area.  I realize that this is still political primary season and there are many more exciting essays vying for your attention.  However, I hope you will indulge me this opportunity to tell you more about the Pebble Mine.

Why should you care about Pebble Mine?

It is probably not going to be in your backyard, so why should you as a sentient and sensitive being expend any of your limited time and energy on this issue?  There are many reasons why Pebble Mine should be stopped, but here I will focus on three major reasons – wildlife (especially salmon), water, and economics.

Let’s begin our plunder-and-pollute tour with a map that shows the Pebble Mine and surrounding areas and waterways.  The big red blotch in the upper right quadrant is a large cluster of mining claims. The black blob in the middle of the red blotch is the proposed Pebble Mine Project.  Photographer Erin McKittrick has a beautiful photo log of the area Pebble Mine proposes to destroy.


1. Threats to wildlife

The freshwater rivers feeding into Bristol Bay are home to some of the most productive fisheries in the world. The undisputed king fish in this region is salmon. It is home to five Pacific salmon species, with the wild sockeye population as particularly abundant. With too many wild fish populations in sharp decline, the sockeye salmon of Bristol Bay have been a remarkable exception as a success story (see Hilborn et al., Proceedings of the National Academy of Sciences, 2003, vol 100, pp 6464-6468). The sustainability of the wild sockeye population in Bristol Bay can be attributed to habitat diversity (lakes, streams, and rivers of various depths, current strengths, and natural predators), strict management of fishing, and excellent water quality due to low toxin exposure. In addition to salmon, the rivers and streams of the Bristol Bay area are also home to Rainbow Trout, Arctic Grayling, Northern Pike, Dolly Varden, Lake Trout, Arctic Char, and Whitefish, which live and spawn in the waterways downstream of the proposed Pebble Mine.

So, why wouldn’t you want a mammoth open-pit copper mine at the headwaters of two of the world’s biggest salmon-producing river systems, the Nushagak and Kvichak Rivers? Because copper is the most toxic heavy metal to aquatic life. (If you live near a major university, check out Ronald Eisler’s volumes on chemical toxicity, particularly the Handbook of Chemical Risk Assessment). Even at relatively low levels, copper accumulates in body tissue and produces irreversible damage. Salmon and their food sources are intolerant to copper beyond naturally occurring levels required for growth and reproduction. Copper impairs a salmon’s sense of smell, making it difficult to find food, locate mates, avoid predators, and navigate to spawning grounds. (If you have the time, please check out this brief video which illustrates the effect of copper on a salmon’s ability to detect and respond to a pheromone.  A more detailed explanation of this experiment can be found here.) Copper also depresses immune function, impairs respiration, and disrupts electrolyte balance. Finally, copper is highly toxic to the salmon’s food sources, including  algae, zooplankton, aquatic insects and fish. For more detail on the effects of copper on salmon, please read this report (18 page pdf).

The Pebble Mine Project promises to be really careful.  No matter how careful, an open-pit copper mine will disperse copper dust. The wind patterns recorded by the company (327 page pdf) indicate winds over the mine site are strong (25% of the readings > 11 mph), with east/southeast winds that will carry copper dust over Lake Iliamna and feeder streams to the east of the mine during the winter months and west/northwest winds that will carry over the Mulchatna River and its tributaries during the warmer months.  To make matters worse, this is a high rainfall and snow pack area, which means there will be runoff into groundwater and surface streams.  Recordings from the company’s weather stations found 900 mm (36 inches) of precipitation during 2007. Toxic exposure to copper is a certainty for this operation. The ore in the Bristol Bay area is very high in sulfur, which means that exposure of the rock to air and water will produce acid rain, changing ph of rivers and destroying vegetation. In addition to copper, other highly toxic heavy metals are likely to leach into the groundwater from the Pebble Mine, including molybdenum, zinc, arsenic, aluminum, selenium, mercury, silver, lead, magnesium, cadmium, antimony, uranium, and chromium.

“How could you have an open-pit tailings pond with zero effect on your subsistence way of life? The real question is what’s the nature, the timing and the magnitude of the effect.”

Bruce Jenkins of Northern Dynasty Minerals speaking to residents of Newhalen, Alaska


The Pebble Mine proposes to drain the headwaters of the Upper Talarick Creek and Koktuli River for mining operations and to create two massive tailing ponds for rock and other mining waste products. The Upper Talarick Creek and Koktuli River are major salmon spawning and trophy trout streams.  Both will be diverted and destroyed by the mine.  The Pebble Mine Project acknowledges that the diversion of water will destroy these streams, but estimate the loss at no more than 0.5% of Bristol Bay salmon stocks. No supporting documentation has been provided for the derivation of this estimate. However, the Pebble Mine Project proposes to compensate for this loss of habitat by “increasing the productivity” of other salmon spawning waterways. How they will increase the productivity of other streams and rivers is unclear. Perhaps they intend to dump farm-raised hatchlings into these streams, but that will reduce biodiversity and increase competition for food.  

The wildlife endangered by the Pebble Mine Project are not limited to salmon, other fish, mollusks, and other aquatic life. Lake Iliamna is home to one of the few species of freshwater seals in existence.  Please visit this site by photographer Scott Dickerson for pictures of these remarkable creatures. The tundra surrounding the Pebble Mine is home to a large caribou herd, along with grizzly and brown bears, and smaller mammals like river otters, mink, red fox, and wolverine. Many of these species depend on the salmon for food.Migratory birds, including sea ducks, winter and breed in the warmer waters of the Bristol Bay. None of these species benefit from exposure to heavy metals and other toxins in the ground and surface waters courtesy of the Pebble Mine Project.

2. Wasting water and waste water

Pebble Mine proposes to waste water on a grand scale. Its daily consumption from the Upper Talarick Creek and Koktuli River will be over 140,000 gallons. To pay for this extravagance, the Pebble Mine Partnership promises to offset the salmon and trout losses from draining these streams at their headwaters. The relatively low grade of the ore and high sulfur content require high water consumption to process the ore and then submerge the rock waste in massive tailing ponds.  Pebble Mine will transform pure water into permanent waste water that then has to be monitored and managed for the foreseeable future. That sounds like plunder to me.

Much of the attention has focused on the two massive tailing ponds.  These ‘ponds’ will eventually hold as much water as the Hoover and Three Gorges dams. The Pebble Mine Partners snivel that the comparison is not fair because the height of the tailing pond dams will be so much less than Hoover or Three Gorges.  True, but what the tailings dams will lack in height they will make up for in length.  We are talking about enormous toxic waste pools that will be around long after the mine has finished its plunder operation – a generous gift to generations to come.

Tailing pond dams fail. In fact, they fail at a higher rate than conventional dams. The current rate of failure is 6 per year. Failures occur because of inadequate design or inadequate structural monitoring.  The design of the tailing pond dams for the Pebble Mine has a unique challenge. They are being built on top of the Lake Clark fault line.  When critics pointed out the proximity to the fault, the company said the fault line was 18 miles from the tailing ponds (based on 1980 geological data, which did not use use state-of-the-art mapping methods). The trouble is that more recent geological maps of the Lake Clark fault using areomagnetic data put the fault line within a mile and possibly directly under the proposed footprint of the tailing ponds.  The company says that Lake Clark fault line has not been very active, although the Lake Clark fault is an extension of the Castle Mountain fault which has been seismically active.

From an environmental threat perspective, opponents should focus on other failings than than tailing pools. Open-pit operations and tailing facilities generate dusting problems, which will disperse copper dust. Seepage from a tailings impoundment will contaminate ground water with heavy metal waste.

The environmental record of metallic sulfide mines, particularly where the ore body is at groundwater, as it is at the Pebble Mine site, is poor. One recent study of recently permitted large mines in the United States found that that sulfide mines are likely to develop pollution problems (Kuipers, J.R. et. al., 2006). The study found that those involving metallic sulfide deposits near groundwater have such a high risk, that water quality exceedances are near certain for acid drainage or contaminant leaching. The analysis found that 85% of these sulfide based mines polluted surface water, 93% of these mines polluted ground water, and of the mines that developed acid mine drainage 89% of the environmental documents for these mines predicted that they would not.


In addition to the heavy metals generated from the copper mining operation, 30% of the ore in the Pebble Mine contains gold. Modern gold mining operations use cyanide in a practice known as cyanide heap-leach mining.  When opponents raised the cyanide issue, the company sniffed that it was unfair because they have not said they were going to use cyanide. More to the point is that the company refuses to say it won’t use cyanide in its operations. No other chemical wash process has proven to be as effective as cyanide in extracting gold and alternatives (bromide, chlorine) would also be toxic. There is no reason to believe that the Pebble Mine will NOT use cyanide.  The Pebble Mine Partnership’s intellectually dishonest strategy is to leave that detail to the final permit request when the public will have no time to react.

The use and disposal of cyanide solutions used to dissolve and extract gold is another environmental concern. Cyanide is a well known poison; hydrogen cyanide is acutely toxic to humans and, in its gaseous state, can be fatal at exposure levels of 100 to 300 parts per million (ppm). Cyanide is likewise harmful to wildlife such as mammals, birds, and fish which can have acute toxicity reactions to even low cyanide exposures.

The most significant risk from use of cyanide solutions in gold mining is possible leaching into soil and groundwater. There exists the potential for catastrophic cyanide spills that could inundate an ecosystem with toxic levels of cyanide. In 2000, heavy rain, ice, and snow caused a breach in a tailings dam (tailings are the cyanide-treated ore wastes, from which gold has been removed) at a gold mine in Baia Mare, Romania resulting in the release of 100,000 cubic meters of cyanide-rich waste into the surrounding watershed. Drinking water supplies were cut off for 2.5 million people and nearly all of the fish in the surrounding waters were killed.


Containment of cyanide-laden waste requires that the tailing ponds be lined to prevent leaching. A responsible mining operation would disclose the use of cyanide up front so regulators know what to look for in the design of the tailing ponds. The Pebble Mine Project has applied for water rights and dam construction permits, making its refusal to disclose its plans regarding cyanide disturbing. This should be a red flag for regulators, assuming they are paying attention.

3. Economic plunder

The Pebble Mine will be lucrative for its owners. The current estimated worth of the metals to be extracted from the site range from 300 to 500 billion dollars. The project will hurt rather than help the people of Alaska, particularly those living and working in the Bristol Bay area. This harsh assessment is justified because mining operations pay almost no royalties for the minerals they extract, the jobs they create are few and short-lived, and the Bristol Bay economy generates many more jobs based on fishing and tourism that it will ever generate from mining.

Here is how the Alaska House Bill 418 (a bill to drastically change mining royalties) summarizes the current state mining royalty structure.

Alaska’s mining industry bears a light tax burden compared to Alaska’s other high value resource industries. State revenue generally amounts to only about 7/10 of 1% of the mined resource value, while an additional 1% is paid to municipalities. State revenue from oil and gas amounts to about 20% of total production value, while an additional 2% is paid to municipalities.


Under the current royalty structure, 300 billion dollars in ore extracted at the Pebble Mine will result in 5 billion going to the people of Alaska.  By contrast, an oil or gas drilling venture worth 300 billion would result in 66 billion going to the people of Alaska. A study on the impact of mining on the Alaskan economy conducted by Thomas Powers, an economics professor at the University of Montana, concluded that metal mining contributes less than one-tenth of one percent of total Alaskan government revenues.

The current royalty structure paid by mining operations may have made sense in 1872 when mining was done mostly by pick and pan, but has five flaws that allow companies to plunder Alaska and toss Alaskans a few dollars in return.  First, state mining royalties are low (3%) relative to oil and gas (20%).  Second, mining royalties are paid on net value whereas as oil and gas royalties are paid on gross value, further reducing that 3% to a pittance. Third, another loophole exempts mining companies from having to pay anything on ore extracted during the first three years of operation. Fourth, exploration costs can be written off against royalties during the first fifteen years of operation (many mining operations do not last beyond fifteen years). Fifth, the state is left to deal with clean-up and reclamation costs after mining operations are closed. It is really is the perfect formula for plunder. It all adds up to minerals for nothing.  Unless the royalty structure for mining is drastically reformed, then Pebble Mine will only benefit the Pebble Mine Partnership of Northern Dynasty (Canada) and Anglo American (UK). (As an aside, Northern Dynasty Minerals would have to pay much, much, much higher royalties if this mine were located in Canada. Beauty, eh?)

Pebble is also promising jobs, but the number of mining jobs will be trivial because this will be a largely mechanized operation.  Hardrock mining jobs continue to decline despite increased production.  Here is what one mining-sponsored economic analysis found. In 1999, hard-rock mining in the western US states produced over 60,000 jobs. Of those jobs, 25,627 were in the mines in the western states. The rest included 9,400 jobs in the District of Columbia (lobbyists!!) and 27,900 in New York state (mining company offices, commodity exchanges, and metals processing). I am sure Pebble Mine will feather nests in Vancouver and London and D.C., but it will not bring many jobs to Bristol Bay.

“It’s transient money with a near-permanent legacy.”

Thomas Power, chairman of the economics department at the University of Montana, on the short-term economic benefit versus long-term clean-up and reclamation of mines.


People in Bristol Bay have been employed in fishing and tourism for generations, with the salmon bringing in over 200 million dollars in annual revenue. Tourism associated with sports fishing is another lucrative endeavor. Native peoples also subsist entirely on food and revenue from the waters of the Bristol Bay area. These long-sustaining and sustainable industries now face a challenge from the plunder-and-pollute Pebble Mine Project. Putting an open-pit copper and gold mine at the headwaters that form the backbone of the fishing industry will not benefit the residents of Bristol Bay.  Copper dust contamination and other toxic run-off from Pebble Mine will hurt the salmon industry well beyond the losses due to the planned destruction of the Upper Talarick Creek and Koktuli River.

What Can You Do To Help?

1. Help spread the word

Pebble Mine is opposed by the vast majority of Bristol Bay residents, including the major native Alaskan tribes; commercial and sports fishing organizations, local tourism organizations, and even some very surprising politicians, like Ted Stevens.  (I never thought I would ever be on the same side of an issue as Ted Stevens. I am sure there must be a blizzard in hell.) The people of Alaska are very aware of this fight, but it needs to be on the national radar. Please consider writing your own blog post (feel free to steal anything or everything from me).  The biggest supporters of the Pebble Mine Project are industries that will benefit from opening the Bristol Bay region up to hardrock mining.

The following organizations have been active in fighting the Pebble Mine. Please consider making a donation of any size to help them get the word out:

Renewable Resource Coalition

Bristol Bay Alliance

Earthwork’s Save Bristol Bay

2. Help wake up the national environmental organizations

Many national environmental organizations have campaigns to stop offshore drilling in Bristol Bay, but have not gotten involved in the fight over Pebble Mine.  With the permitting process underway, their help is critical, particularly in forming partnerships to help local groups fight Pebble Mine in the courts, state regulatory agencies, and court of public opinion. Contact these organizations and request their help:

Sierra Club

85 Second Street, 2nd Floor

San Francisco, CA 94105

Phone: 415-977-5500

Fax: 415-977-5799

Friends of the Earth

1717 Massachusetts Avenue

Suite 600_Washington, DC 20036

Phone: 202-783-7400

Fax: 202-783-0444

Toll Free: 1 877-843-8687


702 H Street, NW

Washington, D.C. 20001

Phone: 202-462-1177

Toll Free: 1 800-326-0959 (Monday – Friday, 9:30 a.m. – 5:00 p.m. EST)

E-mail: info at

Environmental Defense Fund

257 Park Avenue South _

New York, NY 10010

Phone: 212-505-2100

Fax: 212- 505-2375

American Sports Fishing Association

225 Reinekers Lane

Suite 420

Alexandria VA 22314

Phone: 703.519.9691  

Fax 703.519.1872  

Email: info at

The Nature Conservancy

4245 North Fairfax Drive,

Suite 100

Arlington, VA 22203-1606

Phone: 703-841-5300


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    • DWG on May 19, 2008 at 11:31 pm

    Thanks for reading.  Pebble Mine needs to be stopped.


    Also posted at Big Orange

    • 3card on May 20, 2008 at 12:59 am

    …Pebble Mine proposal, (only because I work in the region) but had not realized it had reached the permitting stage.  I cannot believe that even the AK state legislature is corrupt enough to go for this turkey.  In the past they have shown at least some sense in not jeopordizing the goose that lays the golden eggs – Salmon fisheries.  

    The similar Windy Craggy mega copper mine proposal from a few years back that threatened the Alsek/Tatshenshini watershed was successfully stopped.

    In the end, the Tatshenshini campaign was successful. On June 22, 1993 the Tatshenshini-Alsek watershed (approximately 1 million hectares) was designated a Class A provincial park by BC government under Premier Mike Harcourt, thereby killing the Windy Craggy copper mine proposal. On December 15, 1994 the Tatshenshini-Alsek Wilderness Park was declared a World Heritage Site (UNESCO).

    I suppose it was easier for them to oppose Windy Craggy because it was across the line in Canada.

    Like most Alaskans I don’t share in the fervent, almost religious, opposition to drilling in ANWR, but this proposal is a much greater environmental threat.  It also directly threatens the livelihoods of many thousands of Alaskans and others.

    I only have one quibble with the essay.  Easterly or Southeasterly winds will carry sediment away from the lake.  Stated wind directions, by convention, indicate the direction from which the wind blows. Also, the threat from acid runoff cannot be understated. Other than that, great job!

  1. It really should be promoted. I never heard of Pebble Mine. This sort of head’s up is essential if we’re ever going to have the awareness we need to fight environmental destruction in what is rapidly becoming the end of days. Thanks for the info, DWG.

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