If you are following the saga of the proposed Pebble Mine in Bristol Bay, Alaska, you would be forgiven if you thought recent action by the U.S. Army Corps of Engineers (USACE) was the death knell for the proposed mine.

On August 24, the USACE released a letter to the Pebble Limited Partnership. The U.S. Army’s press office proclaimed, “Therefore, the Corps finds that the project, as currently proposed, cannot be permitted under section 404 of the Clean Water Act.”

In reality, the USACE essentially kicked the can down the road. The letter to the Pebble Limited Partnership informed them, “As part of the [Record of Decision] the [Alaska District of the USACE] made Clean Water Act Section 404(b) (1) factual determinations that discharges at the mine site would cause unavoidable adverse impacts to aquatic resources and, preliminarily, that those adverse impacts would result in significant degradation to those aquatic resources.” The Alaska District of the USACE determined that Pebble Limited Partnership would need mitigation measures within the Koktuli River Watershed, where the mine potentially will be located, for all direct and indirect impacts on aquatic resources caused by the mine’s discharges.

The letter went on to outline the ways those damages could be mitigated:

There are three approved mechanisms for providing compensatory mitigation, which include mitigation banks, in-lieu fee programs, and permittee-responsible mitigation with preference, in that order. Your mitigation plan may include a combination of means and mechanisms but must comply with all required components of Rule and be found sufficient to offset the unavoidable adverse impacts to the aquatic resources identified above.

Some reactions critics of the project from both sides of Capitol Hill were less than laudatory of the action. Senator Joe Manchin (D-WV) stated :

A mitigation plan to make up for unavoidable damage from the Pebble Mine is not enough. The Final Environmental Impact Statement for Pebble Mine did not assure me the pristine Bristol Bay region of Alaska, which is home to the world’s most productive salmon fishery, supports 14,000 jobs and generates $1.5 billion of revenue annually, would be sufficiently protected. I again urge the Administration to completely veto a Clean Water Act permit for this project.

Rep. Jared Huffman (D-CA) said :

Delaying the permit for the Pebble Mine is welcome news, but let’s be clear: the only reason this environmental atrocity came this close to happening is because the Trump administration is a favor factory for polluting industries. The previously rejected permit was revived and fast-tracked by this administration, and the only reason they finally hit the pause button is because – thankfully – some individuals close to President Trump made a personal appeal. We can welcome the outcome, but let’s not confuse any of this with environmental stewardship or good government.

This letter did not come as a surprise to the Pebble Limited Partnership. The company responded:

The letter we received today is a normal letter in the permitting process and we are well into an effort to present a mitigation plan to the USACE that complies with the requirements of their letter. A clear reading of the letter shows it is entirely unrelated to recent tweets about Pebble and one-sided news shows. The White House had nothing to do with the letter nor is it the show-stopper described by several in the news media over the weekend.

Now that dust has settled, let’s take a look at the facts included in the Corps’s letter, which should send chills down the spine of anyone who still thinks it is a good idea to permit this mine.

The letter tells us what is at stake:

Therefore, the District has determined that in-kind compensatory mitigation within the Koktuli River Watershed will be required to compensate for all direct and indirect impacts caused by discharges into aquatic resources at the mine site. Direct and indirect impacts at the mine site total 2,825 acres of wetlands, 132.5 acres of open waters, and 129.5 miles of streams.

The District has also determined that compensatory mitigation is required for unavoidable adverse impacts to aquatic resources from discharges associated with the transportation corridor and the port site. Direct and indirect impacts associated with the transportation corridor and port site total 460 acres of wetlands, 231.7 acres of open waters, and 55.5 miles of streams.

Let me help you with the math. Here are the totals for what’s at risk:

• 3,285 acres of wetlands
• 364 acres of open waters
• 185 miles of streams

So somewhere, somehow, the Pebble Limited Partnership is going to mitigate all that damage. As they said, “We will share more details of our initial plan as they become more defined.”

They have until November 20 to do that, although they seem to think it may happen sooner. “Based on our understanding of the substance of the letter, our discussions with the state, our substantial work in the field and our discussions with the USACE we believe our final Comprehensive Management Plan submission will be submitted within weeks and will satisfy all of the requirements of the letter.”

We shall see.

Here’s the rub. Bristol Bay is unique. How will that uniqueness be mitigated? How do you mitigate the loss of the world’s best salmon run?

On August 31, a letter from Representatives Huffman and Peter DeFazio (D-OR) and signed by 31 of their colleagues to EPA administrator Andrew Wheeler, made the point, “There is no level of compensatory mitigation that would be sufficient to address the mine’s irreversible harm to the pristine environment that exists in Bristol Bay.”

The letter went on to ask “that the EPA exercise its authority under the Clean Water Act and oppose the flawed Environmental Impact Statement.”

Let’s hope the administration comes to realize that, as the late Senator Ted Stevens of Alaska said, “This is the wrong mine in the wrong place,” and vetoes the Clean Water Act permit. If the USACE and Environmental Protection Agency don’t see the light, hopeful Congress will make them feel the heat.

Note: This article originally appeared on the Marine Fish Conservation Network’s From the Waterfront blog.