If you were holding your breath for King County’s ruling on the environmental impacts of a proposed Cumberland gravel mine — you’re going to have to hold it a little bit longer.

On April 22, King County’s Permitting Division announced the deadline for the State Environmental Policy Act (SEPA) review of mining company Segale Properties LLC’s new venture was moved from April 25 to June 12.

Here’s some history.

Back in early 2024, Segale applied to open a 990-acre mine in the Cumberland area east of the city of Black Diamond. The proposed mine is separated into pieces surrounding a parcel of land owned by the Washington State Department of Natural Resources.

The proposal was met with fierce resistance from those who would live near the mine and local conservationists; a Feb. 27, 2024 meeting at the Black Diamond Elementary School was standing-room only with angry attendees; presenters from Segale and King County were forced to end the presentation early to move on to the Q&A portion of the night after continued interruptions and shouted questions.

Since the application was submitted, the county has been reviewing Segale’s research into how its mine will affect the environment, like how additional trucks will affect road conditions, how the mine will collect runoff to keep chemicals from trickling into the nearby bodies of water, how the additional noise will impact nearby neighbors, etc.

Segale has said that it will not mine the entire area all at once, but in smaller 50 acres or more sections over time; when they move from one area to another, they’d start the reforestation process of the previous section of the mine.

The company also said that noise will be mitigated by making sure all mining happens behind forest buffers and “excavated down” to further minimize noise, plus mining activity will occur at least a quarter mile from any residents.

Groundwater supply and water quality won’t be affected, nor will stormwater or runoff leave the site, the company said, and traffic will avoid peak hours.

These promises have done little to assuage the fears of locals, who hold that the gravel mine will greatly affect the environment and their quality of life out in rural King County.

Runoff and traffic are just two of the issues often brought up; opponents of the mine say that the expected 600-plus vehicles going in and out of the area every day during peak season will bring a lot of noise, make the roads unsafe, and deteriorate the roads quickly, as they were not built to withstand this sort of traffic in a rural area.

And if there is any runoff from the mine, it could end up in the Black Diamond and Green River Gorge springs, which then feed into the Green River.

There are also concerns that the mine will affect access to the DNR property, which is used as local recreation, and tourism at Kanaskat-Palmer State Park.

There are two ways the county’s June 12 ruling can go.

One is that the county rules that Segale’s proposed mitigations are sufficient and will not significantly affect the environment.

The other is that the county finds the project will significantly affect the environment. This means Segale will be required to prepare an Environmental Impact Statement (EIS), a much more in-depth process for determining how the area will be affected and what Segale will need to do to mitigate those effects.

This could be a long and costly process for Segale, and it also gives locals another chance for public comment and to shape how in-depth the EIS process should be.

Opponents of the Segale Properties mine want to keep the area natural for recreation and protect nearby bodies of water. Photo by Zachary Pratt / pnwadventurequest