A gigantic, Amazon-like warehouse could be headed to vacant fields around the Spokane International Airport. Details were tantalizing, but scarce Thursday.

A company has submitted conceptual plans for a four-story warehouse to the Spokane County Building and Planning Department. The warehouse would contain a whopping 2.5 million square feet of space, according to the paperwork.

The company is not identified in documents filed with the county.

Amazon is expanding the number of fulfillment centers it operates around the country. The size of the warehouse hints at something Amazon-like, and the company’s fulfillment centers often employ 1,000 or more workers to pack and ship products.

However, an Amazon spokeswoman declined to comment Thursday on whether the e-commerce giant was considering an operation in the Spokane area.

“We don’t comment on speculation,” she said.

Coffman Engineers is listed as the applicant for the warehouse. But the company has signed a nondisclosure agreement and can’t discuss the project, said Karl Kolb, general manager of Coffman’s Spokane office.

Business cards for Trammell Crow Co. employees in Seattle and Portland were included in the paperwork filed with the county.

Dallas-based Trammell Crow is developing an Amazon fulfillment center in north Portland, according to media reports. The company has built other Amazon fulfillment centers in Troutdale, Oregon; Redlands, California; the Los Angeles area; and Carlisle, Pennsylvania.

A phone call to Trammell Crow was not returned.

The project near the airport is referred to as “Project Rose.” Amazon is known to use code names for fulfillment centers during the planning and design phases, according to the Thursday edition of the Spokane Journal of Business.

Besides the warehouse, the proposal calls for parking for 309 semitrailers and 1,884 regular parking spaces, according to the paperwork.

The address of the proposed warehouse is 10010 W. Geiger Blvd. Jolt Developments LLC of Mead owns the 118 acres between Interstate 90 and the airport.

A traffic study for the project has been requested by the county’s Transportation Department.

The mystery company’s representatives met in a closed-door meeting Thursday with county staff and officials from other local agencies. During the meeting, local officials discussed what issues the applicant would need to address to get a building permit for the warehouse.

Last fall, Greater Spokane Incorporated submitted a proposal to Amazon to consider the Spokane area for the company’s second headquarters. At the time, local officials said the proposal was a good opportunity for Spokane to get on Amazon’s radar for other economic development projects.

Todd Mielke, GSI’s chief executive officer, could not be reached for comment Thursday.

Amazon has more than 100 fulfillment centers in North America. Amazon Prime, which offers two-day shipping, is driving growth in the number of fulfillment centers, Business Insider reported last fall.

Last year, Amazon held a giant job fair, part of the company’s stated goal of hiring 40,000 to 50,000 new workers for its fulfillment centers. Starting pay for the majority of the jobs, which offer health insurance and a 401(k) match, is typically in the $12-per-hour range for full-time workers, according Amazon’s job listings.

Spokesman reporter Amy Edelen contributed to this report.