Recorded Conversations with Pebble Mine Executives Reveal Plans to Build Massive 180-Year Mine at the Headwaters of Bristol Bay in Alaska

WASHINGTON--()--Today the Washington DC-based non-profit the Environmental Investigation Agency (EIA) released recordings of conversations between EIA investigators and executives of Pebble Limited Partnership and Northern Dynasty Minerals (Pebble), the companies behind the contested Pebble Mine project in Alaska. The recordings, which EIA has dubbed “The Pebble Tapes,” reveal Pebble’s plans to build a large and long-lived mine at the headwaters of Bristol Bay in western Alaska.

The tapes also reveal Pebble’s apparent plans to use the infrastructure included in its mine plan to open up other expansive swathes of western Alaska to mining, including through the activation of the Donlin Mine, a project that already has federal permits and could become economically viable overnight if the Pebble project is approved.

Tom Collier, the CEO of Pebble Limited Partnership, and Ronald Thiessen, the president and CEO of Northern Dynasty, of which Pebble is a wholly-owned subsidiary, spoke with EIA investigators during August and September after the investigators expressed interest in investment opportunities related to the Pebble project. Their conversations, which were recorded, contain multiple statements by Collier and Thiessen that contradict, or in some instances color, previous public statements by company executives as well as assertions in official company materials that Pebble is intended to be only a small 20-year mine, as described in the Clean Water Act permit application for the project.

Statements made by Collier in the recordings also call into question the Congressional testimony he submitted on behalf of Pebble regarding the company’s plans for expansion. In October 2019, Collier submitted written testimony to the House Subcommittee on Water Resources and the Environment stating that, “Pebble has planned a smaller, smarter mine” and that it has “no current plans, in its application or in any other way, for expansion.”

The proposal from Pebble considered in the Environmental Impact Statement (EIS) is for an operations phase for the mine that would last for 20 years with a daily process rate of 180,000 tons. The EIA recordings capture a different version of Pebble’s plans indicating that the company envisions a project with a 180-200 year mine life, and with expansion after the first 20 years, including an expected increase in daily production rates to between 220,000 and 320,000 tons.

EIA Executive Director Alexander von Bismarck said, “These tapes show that potential investors are given an entirely different vision for this massive mine than the government and the public. We think that is important information to release. The public, and especially the people of Alaska, should know about the scope of a project with permanent impacts on one of the most pristine ecosystems on Earth.”

When asked by investigators if growth of the mine past the scale currently applied for would be “unstoppable,” Thiessen simply said “Yes.” Then he explained further: “Once you have something like this in production why would you want to stop? And even, at the end of the day its footprint is so tiny. If we mined the whole valley it’s 25 square miles.” In another conversation, Thiessen asked, “Who’s gonna stop a mine that has 180— at a 160,000 metric tons per day, the first deposit that we’ve discovered at Pebble – and there will be more – but the first one lasts 180 years.”

In response to a question from EIA about expansion after the first 20 years Collier characterized the likelihood of expansion as almost 100%. He also explained how the recently-approved “northern corridor route” facilitates expansion, stating: “And so now we’re going to be building a northern corridor. We’ll have a slurry pipeline as part of it so the concentrate will go down to the coast by pipeline. And it makes a lot of things easier for us. It makes expansion much easier.”

Pebble also told EIA that it plans to submit an application for expansion after the permit now being considered by the Army Corps of Engineers, is approved. Thiessen confirmed, “during that twenty years, you’re gonna make the application to continue for another twenty.”

Similarly, Thiessen shared with EIA its interest in developing additional mines in the area saying, “Now Pebble itself has…425 square miles of mineral claims, and so there could be more mines on the Pebble lands over time…We have other sites that we’ve drilled into and we have ore-grade mineralization in other areas in that 425 square miles but we don’t talk about it too much because right now we want people to focus on only Pebble…”

Pebble also confirmed its interest in using the infrastructure that will be put in place as part of the Pebble project to facilitate activation of the Donlin mine. According to Thiessen, the Donlin mine is economically unviable unless it can use the roads and pipelines that will be built by Pebble to export its ore. Thiessen explained, “There is another project that’s 175 miles north of Pebble. It’s called the Donlin Project… …there is a lot of logic to us joining forces to make a single corridor.” Collier also weighed in stating, “if you flip the Pebble switch on, it’s likely that you may be also flipping on the Donlin switch.”

“While the public is told this is a 20-year project, investors are told it will go for up to 200 years. While the public is told it will be 5 square miles, investors are told that it could spread over the entire valley and literally pave the way for other mines, hundreds of miles away,” said von Bismarck.

The Pebble Tapes cover discussions between EIA investigators and Pebble on a number of other topics including: the Alaska Governor, the Army Corps of Engineers, the Northern Corridor, Alaska senators, Alaska politics, corporate structure, water treatment, Trump Administration and EPA veto.

They can be viewed at


The Pebble Tapes are organized by topic and edited for brevity within each topic. Where the investigators’ voices can be heard, they have been re-recorded verbatim by an actor.

The EIA investigators, who spoke with Collier and Thiessen as potential investors in the Pebble Mine project via multiple video calls in August and September 2020, recorded those conversations in accordance with all applicable laws.


Lindsay Moran, Environmental Investigation Agency,


Lindsay Moran, Environmental Investigation Agency,