But its internal emails indicate that Salt Lake City Mayor Jackie Biskupski has stood firm in talks with the agency: UTA committed to pay for the relocation, and the city, at least at one point, was not going to be a source of funds.
In a March email obtained by The Salt Lake Tribune through a request for records related to the project, UTA President and CEO Jerry Benson recounted a "tense" meeting with Biskupski, in which the mayor "said the city will not contribute to the cost of the airport [TRAX] station."
The Salt Lake Tribune asked UTA and Salt Lake City to provide all written correspondence within the past year that relates to the airport TRAX expansion. UTA says 92 documents are protected by attorney-client privilege or because they were confidential drafts. The remaining documents provide no indication that the mayor has budged since the March meeting even as the City Council has expressed concern about the project's status.
Biskupski declined an interview for this story, saying through a spokesperson: "UTA has to decide what level of services they want to provide at the airport. The city's providing a world-class airport that serves the entire state."
'A serious choice' • Things were different when UTA signed an interlocal agreement with Salt Lake City to pay "all reasonable and necessary costs" to move the station.
It was June 2008, amid recession, and UTA was committing to a far-off airport expansion that had been on hold for years.
More importantly, agency leaders have since said, UTA didn't anticipate the pricey elevated track called for by the airport's eventual design. Benson and former UTA board Chairman H. David Burton have quoted the expected cost at $5 million, and a slideshow prepared by UTA in March says the agency originally contemplated $5 million for a new station and $10 million for a quarter-mile of new track.
The $68.5 million project now planned requires twice as much track, most of it elevated, and an elevated station that would drop off and pick up travelers across a skybridge from a gleaming new terminal.
The alternative is that a ground-level station would need to be located 1,200 feet away from the terminal, leaving travelers to lug their bags the length of four football fields.
Benson said that when the elevated track and station became the preferred option which it remains for all involved Biskupski's predecessor, Ralph Becker, indicated informally that Salt Lake City would chip in.
Becker wasn't specific when asked by The Tribune about those discussions, saying "There is just about always a way to finance improvements if you've got smart, creative people handling financing and people who want to work together to get a project done."
Biskupski wrote to Benson that the partners were "off to a good start" in June 2016, after she addressed UTA's board and urged trustees to support paying $4.3 million to design the elevated track.
"We have a serious choice to make," Biskupski told the board. "This station and the rail component of our new world-class airport can either be a bright spot in the state-of-the-art facility ... or it can be the missing piece of an airport designed with traveler comfort and convenience in mind."
But while Biskupski told the board then that she didn't want the full cost "just to fall in your lap" and that the city would help seek federal and state funding, discussions between UTA and the mayor's office evidently became marred by Biskupski's irritation at a perceived lack of initiative from UTA.
When Benson proposed a sitdown with the mayor, a Biskupski staffer wrote back that the mayor wanted to meet only if Benson had "a plan to move forward." Benson withdrew his request.
February internal emails from UTA indicate that the city had asked the agency to come up with $2 million per year for bond payments and that UTA hoped to impress upon the city the devastating impact those payments would have on its other services.
The agency rendered a map of Salt Lake City's bus routes, with the downtown awash in red, representing needed cuts: Third Avenue, 900 South, 11th Avenue, 1700 South, State Capitol, Industrial Park and International Center.
UTA officials chose those routes to give city leaders a sense of magnitude, Benson said, not as a serious contemplation of likely cuts.
"You could imagine a scenario where you take the  interlocal agreement and you say, 'UTA will pay the cost of the relocation,' " he said. "And you say, 'All right, the cost is $68 million. UTA, you're legally obligated to do that, and you're not going to get a dime from anybody.' Well, where would [we] get that money?"
In April, Salt Lake City UTA board representative Keith Bartholomew resigned from the board at Biskupski's request after suggesting that the city's airport designs had led to unforeseen cost increases.
Biskupski's pick to take Bartholomew's place, state Sen. Jim Dabakis, D-Salt Lake City, said this week that he hasn't yet developed a stand on the issue. His appointment is pending approval from the City Council.
Lane Beattie, president and CEO of the Salt Lake Chamber, has attended meetings with Biskupski and Benson and accompanied them to Washington, D.C., to lobby for a federal loan that would defer payments on up to 48 percent of the cost for five years.
Beattie said he's confident that the airport extension will be "an economic boon for all" and that the debate over funding is "one of those silly fights."
Work needs to begin by spring 2018 if the proposed extension is to be completed by the new terminal's August 2020 opening another condition agreed to by UTA in the interlocal agreement. Were UTA and the city to agree to a lower-cost extension, Benson said, they would have little time for the additional design and engineering work.
"We can see a goal and we're committed to working with each other to get to that goal, but it's not clear how we're going to get there," he said.
'Skin in the game' • Before an early February meeting with the city, UTA Chief Planning Officer Matthew Sibul wrote that UTA could contribute about $10.3 million toward construction $4 million in federal grant funds, a $1.3 million fare surcharge at the airport and $5 million in other local sources.
That level of funding "meets the 'reasonable' test from 2008," Sibul wrote, though it was "a little bit scary" for an agency that spends a third of its operating budget on debt payments as much as it spends on bus service.
"We need to have some skin in the game that others consider reasonable," he said.
To imagine how it might scrounge up the remaining $58.2 million, UTA asked Zions Public Finance to detail a half-dozen other possible sources of available funds.
The full list includes county and city hotel taxes, city parking fees, county rental-car taxes, a parking sales tax (parking is now exempt from sales tax), state gas taxes and one-time state funds.
Most of those sources would require legislative approval either at the state, county or city level or some combination and are characterized by Zions as "difficult," "doubtful" or "not likely."
"The two most likely revenue sources appear to be [hotel] taxes and an increase in parking fees in Salt Lake City," according to the Zions report.
Salt Lake County spokeswoman Michelle Schmitt said in response to a request for comment on the analysis: "UTA and the city made a commitment, so we need to see what they can come up with."
County residents paid through vehicle registration fees in 2008, when Salt Lake City was short $35 million to complete the $350 million extension.
The city had planned to use available airport funds but was disallowed by legislation still in effect sponsored by Sen. Curtis Bramble, R-Provo, under pressure from Delta Air Lines.
Zions wrote that if Bramble's language was removed from state law, the airport could fully fund the TRAX extension with a 10 percent increase in parking fees.
Bramble said he would be amenable to that if "the facts warranted it" but that he would want to review ridership numbers.
UTA did not have readily available numbers for the airport portion of the Green Line, which runs east from West Valley into downtown Salt Lake, then west to its last stop at the airport. Through the end of April, rides along the entire line were on pace for about 4.5 million in 2017, slightly down from 4.7 million in 2016, which had dipped from 4.9 million in 2015 and nearly 5 million in 2014.
Salt Lake City Council members, for their part, have made few public comments but have privately expressed a willingness to support some level of city funding while feeling unease that the state angling for a slice of airport revenues might step in to fill the gap instead.
A December email that Salt Lake City legislative adviser Lynn Pace wrote to lobbyists said he'd met with the council and that "they made it very clear" that they didn't want Pace or city lobbyists to bring up the TRAX relocation to legislators.
Said City Councilman Derek Kitchen: "Maybe at the intellectual level, it might make sense to think of the state as a partner here, but in practicality, if we pull the state in, we risk losing our asset. If we really want this, the city needs to explore all the options that are within our control."
Kitchen added that he's "begging" to be included in the conversation.
"I think this has become a political issue, which is unfortunate, because I don't know that there's a single person out there who doesn't think that TRAX should be extended all the way through the airport."