Hilcorp wants to dig a 95-acre gravel pit near the Putuligayuk River

Hilcorp Alaska wants to dig a new gravel pit on the North Slope, about 95 acres of tundra near the Putuligayuk River. The state is taking comment on it through Sept. 4.

Roughly 30 of those acres would be temporary. The access road and the overburden berms come out at closure. The 64-acre pit does not.

Nearly all of that ground counts as wetland. Permafrost keeps the soils saturated through the summer, and wetlands cover more than 82 percent of the Arctic Coastal Plain, according to a U.S. Forest Service ecological survey.

Hilcorp is proposing no compensatory mitigation, arguing there is no way to replace what the pit takes. Wetlands on the North Slope form through permafrost action over centuries, the application says, and the growing season runs 60 days, making creation or restoration impracticable. Federal rules generally require compensating for wetland losses, with an exception where doing so is not practicable.

The site is called Put 29. A 1,000-foot access road, 36 feet wide at the surface, would run off the existing gravel road to Drillsite 15. A 24-inch culvert would carry seasonal water, and thermal berms around the pit are meant to hold the permafrost in place. Road construction is scheduled for October 2026, with mining beginning no sooner than 2027.

Kirsten Hoppe, Hilcorp's applicant contact on the filing, said the project is needed for continued oil and gas development because current gravel sources are being depleted across the North Slope.

The Alaska Department of Environmental Conservation opened comment Aug. 20 on the water-quality certification and closes it Sept. 4. Its review covers water quality impacts only. The U.S. Army Corps of Engineers ran its own comment period on the mine and road, which closed Aug. 18.

No tribal government, borough resident or subsistence user appears in either notice, and neither agency has made a final decision.