Glacier Northwest dropped its appeal of a federal court ruling that requires the company to comply with some of the nation’s most far-reaching environmental laws before it can move forward on its proposed pier on Maury Island.

Last week’s decision by the corporation and its legal team came days before oral arguments were scheduled to begin before the 9th Circuit Court of Appeals next week.

Glacier’s move means that both it and the U.S. Army Corps of Engineers will have to comply with U.S. District Judge Ricardo Martinez’s decision issued last August, which put a temporary, 11th-hour halt to the project.

Martinez ruled that federal agencies failed to uphold the nation’s strictest environmental law when it awarded the corporation a permit to move forward on a 305-foot barge-loading pier. Among other things, Martinez ruled, the Corps should have required an Environmental Impact Statement, or EIS, before issuing a permit.

In December, the federal government decided not to appeal Martinez’s decision, but Glacier remained in the case as an “intervenor.”

Pete Stoltz, a spokesman for the company, said on Monday that Glacier officials decided it made sense to drop the appeal. The corporation filed a one-page request to voluntarily dismiss the appeal on Friday.

“We’re just going to go through with the permit process. We’ve got that well under way,” he said.

Amy Carey, president of Preserve Our Islands, a Vashon-based group opposed to the mine-expansion project, said she was pleased by the corporation’s decision.

The move, she said, means Glacier realizes “the ruling was sound, that there’s a need for an EIS, that the injunction was valid and that they will be heeding fully the Martinez ruling.”

“We’ve never had Glacier dismiss an appeal or legal action voluntarily before,” she said, adding, “I commend Glacier for recognizing that the right thing to do was to move forward in a positive fashion.”

Meanwhile, Glacier officials and conservation leaders in Seattle continue to work on a potential purchase of Glacier’s 237-acre site on Maury Island. According to both Carey and Stoltz, an appraisal is under way, a key step in the complex sales process.

Lawmakers set aside $15 million from the Asarco clean-up settlement and other hazardous-waste-related proceeds to purchase the site. Depending on the appraisal and negotiations, additional funds will likely be needed to secure a purchase.