King County officials have rezoned the former K2 manufacturing site, opening the door to its rebirth as a commercial center while angering some Islanders who believe the issue was not fully vetted by the community.

The change makes the site a mile south of town, once zoned industrial, both a commercial and industrial area. The rezoning, proposed as part of King County’s update to its comprehensive plan, became final a couple of weeks ago, when the county council approved the updated plan.

Such a rezone has been considered critical to the building’s sale; K2 officials have said it had to be rezoned in order for them to sell the mammoth piece of property.

Dick Sontgerath and Truman O’Brien, two Islanders who want to redevelop the site, have also said the rezone is needed. The two have signed an agreement to purchase the building, pending — among other things — the property’s rezone.

“I’m delighted,” O’Brien said of the rezone.

Even if Sontgerath and O’Brien’s redevelopment plans fall through, another buyer would likely require commercial zoning, he added.

“If we don’t do something with it, someone’s got to do something. And you know darn well no industry is going to move to the Island,” O’Brien said. “It’s just ludicrous that someone would be upset about this.”

But Tom Bangasser, a businessman and Vashon College founder who has expressed an interest in the college obtaining the property, said he believes the county failed to vet the issue publicly before making a decision on the matter.

“They came through a back door without any public input and got the zoning change,” he said. “And I consider that very inappropriate.”

The rezone opens the door, he added, to the Vashon Library’s possible move to the K2 site. The King County Library System has signed a letter of intent with Sontgerath and O’Brien, pledging to purchase a free-standing building at the site should the two men consummate the deal.

Should the library move, Bangasser added, “It’s going to have a significant impact on our town core.”

Others, however, said there was ample public notice and that the community still has a chance to weigh in on the building’s fate.

Sharon Nelson, chief of staff to County Councilman Dow Constantine, said the comprehensive plan update had been posted on the county’s Web site for months, and the county has held numerous hearings about various aspects of the plan.

She and others said the issue was also brought to the Vashon-Maury Island Community Council’s land use committee, which said it wanted to explore the issue further.

Melodie Woods, who recently took over as chair of that committee, said she’s unsure how the community council’s review of the project ultimately unfolded. But she added that she strongly favors a rezone, since it’s likely the only way to ensure a new life for the sprawling complex.

“Quite honestly, with my official land use hat on, I think it would be a shame to see that K2 building sit there unsold and deteriorate,” she said. “It’s in a prime location. It’s a great asset. … And I firmly believe it should be redeveloped. If a rezone helps, I’m all for it.”

Woods said she and others active on the community council are working to arrange a town hall meeting in December, where Islanders would get a chance to discuss both the library’s potential move and the site’s redevelopment with library officials, Sontgerath, O’Brien and others.

“The fact that it’s been rezoned doesn’t mean that Truman and Dick will buy it or that the library will move,” she said. “There are still a lot of things in play that will determine the fate of that building.”

Sontgerath and O’Brien, who are looking for investors to make the multimillion-dollar project come to fruition, have until next month to close on the deal.

According to preliminary plans, they hope to transform the yawning building into a quasi-community center, with an athletic club, medical facilities, office space, small hotel, commercial kitchen and even housing units along the back edge of the 18-acre property.