A planned retail development and parking garage at the old Airport Plaza Hotel location in SeaTac is set to go ahead, although light rail will take a greater chunk of the site than expected.

Sound Transit plans to purchase about 50,000 feet of the property.

The SeaTac City Council is expected to take action on June 26 on amendments to a previous development agreement for the site at 18613 International Boulevard on the southeast side of Sea-Tac International Airport.

Developers want to count land under the proposed elevated light rail, which will be owned by Sound Transit, as green space in calculating how many parking slots the garage is allowed.

Planning Director Steve Butler explained at a May 22 presentation on the new agreement that developers are required to leave 10 percent of a project as green space. However, they can qualify for more parking spaces by providing bonus green space.

"It is a little bit unusual to consider space owned by someone else as (your) green space," Deputy Mayor Ralph Shape told the developers.

But project officials indicated that not receiving the bonus parking would be a deal breaker.

Without the added stalls, the garage would not be economically viable, they said.

Developers also promised to landscape and maintain the green space.

"We never envisioned Sound Transit would take so much," Councilman Joe Brennan commented.

He noted that he doesn't care who owns the green space along 28th Avenue South at the back of the project because green space was taken out of the development in the front when "everything was crunched forward" by Sound Transit's large purchase.

In other business, council members extended for six months interim design standards for the South 154th Street light-rail station area.

"For a good public outreach program, we need the interim standards extended one more time," Butler said.

After discussing proposed standards with interested parties, he should have permanent design criteria for the council to vote on in October, Butler noted.

A deal to bring a Starbucks to the location can go forward under the interim standards, he added.