Permit application reveals size of scaled-down Pebble project

  • The scaled-down version of the Pebble mine project would still be a massive undertaking, as seen in the map above. The heart of the operation would be the mine pit, seen in gray at right, that would be 6,500 feet long, 5,500 feet wide and up to 1,750 feet deep. A 230-megawatt natural gas fed power plant, the second-largest power plant in the state, would fuel the operation that proponents say would employ 850 full-time and about 2,000 during four years of construction. At the upper left is the North Fork of the Koktuli River and at upper left is the Upper Talarik Creek, which feeds Iliamna Lake and the Kvichak River. (Map via Pebble Ltd. Partnership Section 404 application)

The official Pebble mine plan released Jan. 5 by federal regulators describes a scaled-back project relative to prior concepts, but opponents contend it is a way for the company to get its foot in the door for future expansion.

Published by the Alaska District of the U.S. Army Corps of Engineers, the plan details a project that is much more than a mine. According to Pebble’s plan documents, its reach would stretch 187 miles from the mine site north of Iliamna Lake to the edge of the Sterling Highway on the southern Kenai Peninsula.

In between would be a natural gas pipeline up to 12 inches wide traversing the Cook Inlet sea floor for 95 miles from the Anchor Point area to a deepwater port at Amakdedori west of Augustine Island.

From there, a two-lane, private road would run 35 miles northwest to a ferry terminal on the south shore of Iliamna Lake. An ice-breaking ferry would then shuttle materials 18 miles across roughly the midpoint of the massive Iliamna Lake, which is the largest in Alaska.

Another 30 miles of industrial road would connect the north ferry terminal near the village of Newhalen with the mine site. The gas pipeline would follow the rest of the transportation corridor to the mine.

In early October, Pebble CEO Tom Collier unveiled a rough outline to the company’s plans. Collier said then the mine the company intends to construct is smaller than what has long been speculated and incorporates stakeholder concerns both in the footprint of the mine and broader project designs.

The ferry, for instance, would be employed to reduce road construction and associated impacts to wetlands, according to Collier.

He reiterated as much in a Jan. 5 statement issued by Pebble.

“We believe that as Alaskans become more familiar with our proposed project design and the environmental safeguards it incorporates, there will (be) an increasing degree of support for the project, and the significant economic potential it represents for the State of Alaska,” Collier said.

Pebble estimates the project will generate about 2,000 jobs during its four-year construction and about 850 full-time positions over its 20-year life.

The now-public Pebble project plans were submitted to the Corps Dec. 22 in Pebble’s wetlands discharge permit application, required under Section 404 of the Clean Water Act.

The Army Corps of Engineers first reviews wetlands permit applications and if deemed complete issues a public notice announcing the proposal within 15 days of the application and makes it available to the public. The Corps also issues a determination on what level of environmental review an application necessitates and, unsurprisingly in this case, deemed Pebble worthy of a full environmental impact statement.

Corps Alaska regulatory officials have said the average EIS for a large project takes four to five years, while Collier has said he hopes the project can be approved in three.

The next step is for the Corps to select a third-party contractor to develop the EIS.

Ron Thiessen, CEO of Pebble’s parent company Northern Dynasty Minerals Ltd. said Pebble expects to sign a memorandum of agreement with the Corps “in the very near term” and subsequently issue a request for proposals from which the Corps will select the EIS drafter.

At the end of the road but the center of controversy, the mine site would include a suite of facilities over several square miles. The heart of the operation would be the mine pit: 6,500 feet long; 5,500 feet wide and up to 1,750 feet deep.

A large bulk tailings storage facility capable of holding 950 million tons of waste rock would collect most of the milled ore. A smaller, lined tailings storage cell designed to hold 135 million tons of potentially acid generating mine waste would be segregated from the bulk tailings but be behind the same series of tailings dams.

The storage facilities are designed to handle mine waste generated over 20 years of operations, according to Pebble’s documents.

The primary tailings embankment would be 600 feet tall and three others would be between 60 and 420 feet tall. Each would have a 2.6-to-1 slope, according to Pebble.

The natural gas pipeline would terminate at and feed a 230-megawatt power plant, which would provide electricity to the mine and drastically reduce the need for diesel fuel storage, the application notes.

For comparison, the power plant would be large enough to supply Golden Valley Electric Association, the electric utility for Fairbanks and surrounding areas, with enough electricity to meet its historical peak demand of 223 megawatts.

The onsite facilities would all be in the Koktuli River watershed and avoid Upper Talarik Creek. Avoiding the Talarik drainage, which feeds Iliamna Lake and the Kvichak River, would seemingly avoid any potential damage to the Kvichak’s immense sockeye salmon runs, a point Collier has emphasized as proof of the company’s efforts to minimize its impacts to salmon habitat.

Pebble will not use leaching processes that require cyanide to extract gold, which will lower recovery by 15 percent, according to Collier.

However, mine opponents have noted the north and south branches of the Koktuli River are primary spawning habitat for the large run of chinook salmon that return to the Nushugak River system.

Overall, the mine site would fill 3,190 acres of wetlands and water bodies, according to Pebble.

The Environmental Protection Agency determined in 2014 — based on the conclusions of its Bristol Bay Watershed Assessment — that any project resulting in the loss of more than 1,100 acres of wetlands and water bodies in the area would be an unacceptable impact.

How Pebble will, or can, sufficiently mitigate the wetlands losses is unclear. The environmental offsets will be established as the lengthy permitting process plays out, according to the application.

Active mining from the pit would occur for 14 years and the final six years of operation would focus on mineral recovery from a stockpile of low-grade ore.

As planned, the Pebble mine would produce 600,000 tons of copper-gold concentrate and 15,000 tons of molybdenum per year from 58 million tons of processed ore.

Statements from several groups fighting the proposed mine said the tempered plan changes little.

“The plan released (Jan. 5) includes only a fraction of the ore within the Pebble deposit, indicating that the impacts could be vastly greater than what’s indicated on the application we see today,” Trout Unlimited Alaska Director Nelli Williams said. “It is clear that Pebble is continuing to deceive and mislead Alaskans and Americans, and their ‘new’ plan is nothing more than the same old threat wrapped in a package they hope is more digestible. Don’t be fooled by this incomplete proposal.”

While Pebble’s application is for a 20-year mine with a single pit to reduce its impact, opponents note investor pitches and statements from leaders of Northern Dynasty Minerals highlighting the immense size of the Pebble deposit.

A November Northern Dynasty investor presentation stresses Pebble as “the world’s largest undeveloped copper and gold resource.”

In its Section 404 application, Pebble notes the total deposit is estimated to hold 80.6 billion pounds of copper, 5.5 billion pounds of molybdenum and 107 million ounces of gold.

However, the single pit would allow for recovery of just 6.7 billion pounds of cooper, 353 million pounds of molybdenum and 10.7 million ounces of gold.

Collier has acknowledged the company might look to expand after initial production commences but contends growing the project would require additional rounds of environmental reviews and permitting that would be independent from any approvals Pebble already had.

He said in a December interview that the company does not have a definitive cost estimate on its massive undertaking, but he did say Pebble is confident in the project’s economics at current metal prices.

Elwood Brehmer can be reached at [email protected].

Updated: 
03/21/2018 - 12:30pm

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