The six-hour-long event, in three segments over Sunday and Monday, was paid for using fees paid by airport customers.

The figurative and literal centerpiece was a scale model of a Boeing 787 wing. DIA hopes the aircraft, currently in testing, will be the vehicle for a long-awaited direct flight to Asia.

The model was constructed by airport maintenance staff.

Two airport employees who worked on the project discussed its details with 9Wants to Know Investigator Kyle Clark on the condition of anonymity, fearing they would lose their jobs for criticizing the project.

Both said they were instructed by managers to submit their overtime claims for the construction and set-up of the wing as "snow removal."

During the event, airport employees, including Kim Day, the manager of aviation, handed out 15,000 cupcakes to customers and fellow employees.

"It's really a thank you for everyone who works here and everyone who uses our airport," Day said.

On Sunday, Day was asked by a 9NEWS photojournalist how much was spent on the event.

"I have no idea, no idea," Day responded.

9Wants to Know first inquired about the cost of the event last Friday.

In an interview Tuesday, airport spokesman Jeff Green said he could not provide an estimate of the cost.

"I don't know if we have a way to bring a final number in just yet since the event happened just yesterday," Green said.

Green said he was unaware how much money was initially approved for the project.

The only hard number offered by DIA was an expenditure of $9,000 for the 15,000 cupcakes.

Based on that figure and on discussions with the two airport employees who worked on the event, 9Wants to Know made the conservative estimate that the event cost $40,000 for materials, food, graphic design for the wing, and overtime for the replica's construction, setup and tear-down.

"Even if we want to say it cost $40,000 for the marketing and goodwill that we go for that money, if it is that much, [it] is way better than putting an ad in the newspaper," Green said.

The party was a big hit with airport guests and was a proper way to thank airport employees for 15 years of success, Green said.

Green says the airport will review employee timecards to see if party-related expenses were logged as snow removal.

"I don't know that they specifically wrote it down as snow removal," Green said. "But the overtime, regardless of what it's for, as long as it's approved, is coming out of the same budget."

Green said it's possible that workers on standby during snow removal shifts were enlisted to work on the project. He acknowledged that workers involved in set-up and cleanup for the weekend event were not on snow duty.

"There was no attempt to hide the expense," Green said. "Everything we do out here has to be transparent."

In 2008, the snow removal operation at DIA was criticized in an audit by City and County Auditor Dennis Gallagher.

The audit found the program had "a lack of internal controls, improper payments of overtime, and improper reporting and payment of regular work hours."

At the time, airport spokesman Green told The Denver Post that DIA agreed the program needed "better procedures and internal controls."

Green said Tuesday the current issues raised by employees were not related to the past problems in the snow removal operation.

(KUSA-TV © 2010 Multimedia Holdings Corporation)