I’ve worked in mining for decades. Pebble’s environmental impact statement is fatally flawed.

During my 35-year career I have performed permitting, design and environmental work at more than 50 mines and mining projects across the world. As former head of environment for Rio Tinto’s Copper and Diamonds Product Group, I also gained a deep understanding of the challenges posed by the responsible development, operation and closure of large copper mines.

The proposed Pebble Mine in Bristol Bay is located in the most sensitive, globally significant and challenging environmental setting of any mining project I have ever reviewed. It will be extremely difficult to construct, operate and close a commercially viable mine in this setting that does not do permanent harm to the region’s world-class salmon fishery. I believe mining is needed to sustain our society, but that does not mean that all mines should be developed, no matter their environmental, commercial and social cost.

Right now, the Pebble Partnership is completing an Environmental Impact Statement (EIS) for a mining project located in the headwaters of two of the world’s most important salmon-bearing rivers. The proposed project would only mine about 10% of the resource, but even this smaller mine would create very large environmental impacts and risks in the heart of the Bristol Bay region. Despite these concerns, the EIS is scheduled for completion in roughly half the time of a typical new mining project. The draft EIS released in 2019 does not even meet industry standard practice. It lacks critical detail and contains an unacceptable number of deficiencies, omissions and errors. In many cases its conclusions are clearly wrong.

The deep flaws in the EIS have been forcefully highlighted by agencies of the Trump Administration, including the Department of the Interior, Environmental Protection Agency, Fish and Wildlife Service, and National Marine Fisheries Service. Despite the strategic deficiencies, the Army Corps of Engineers continues to stand by their rushed schedule which does not seek new field data or additional public comment on the next revision of the EIS.

In my professional opinion, the small mine being evaluated by the draft EIS is almost certainly not economically feasible, with likely financial losses in the billions of dollars. A much larger mine would almost certainly need to be constructed to attain a positive rate of return on the very large initial capital investment. The EIS thus fails to evaluate the true environmental impacts and risks associated with a viable mining project. Even a small expansion of the project to extract 20% of the ore body would almost double the size of the disturbed footprint, quadruple water quality risks and likely spread large-scale impacts into three different river drainage basins. Although such a mine expansion would need to be re-permitted, the artificial fragmentation of the full-scale mine plan would hide the full environmental harm of the project until after half of the impacts had already occurred. This is clearly unfair to the people of Alaska, who wish to make an informed decision about the relative benefits, impacts and risks of the project.

As a lifelong mining professional who cares about the reputation of our industry, I am deeply concerned about the great risks posed by the Pebble Project and by its embarrassingly inadequate EIS process. I would urge the Army Corp of Engineers to scrap this fatally flawed draft document and begin work on a new EIS that is based on sound science and rigorous analysis and that evaluates the true environmental impacts of a much larger economically-credible mine plan. This is only fair to the communities and fishermen of Bristol Bay, the people of Alaska, and to the broader mining industry.

Rich Borden has worked for more than three decades in the mining industry, including as the former head of environment for Rio Tinto’s Copper and Diamonds Product Group.

The views expressed here are the writer’s and are not necessarily endorsed by the Anchorage Daily News, which welcomes a broad range of viewpoints. To submit a piece for consideration, email commentary(at)adn.com. Send submissions shorter than 200 words to letters@adn.com or click here to submit via any web browser. Read our full guidelines for letters and commentaries here.