WESTMINSTER, Colo. — Since a large crack on U.S. 36 turned into a growing sinkhole this weekend, many people have wondered if the private concessionaire that operates the roadway and collects tolls will have to pay for the repairs.

The short answer appears to be no, but neither side will say who is going to pay for what appears to be an expensive repair, after the soil underneath the roadway eroded.

Plenary Roads Denver, the private company that paid for, designed and constructed half of U.S. 36, currently is under a 50-year contract with the state to collect tolls in an express lane that runs the entire length of highway. The company is also responsible for maintenance and rehabilitation of the roadway, under that contract.

RELATED: US 36 will be closed through at least Tuesday due to giant crack

"While this incident is ongoing, CDOT remains focused on the safety of the travelling public and staff on the scene, as well as the prompt resumption of a sustainable detour along US 36,” Colorado Department of Tranportation spokesman Matt Inzeo wrote in a statement. “It is an all hands on deck effort focused on providing a streamlined and seamless response.”

“Once operations are stabilized, we will explore the relationship between project partners."

But the crack, which CDOT now says began forming last Monday, is on a portion of highway redesigned under phase one of the U.S. 36 project, which a Plenary spokesman confirmed was built before his company came on board. Plenary designed and constructed phase two of the project.

Along with the cost of repairing the damaged stretch of roadway, CDOT may also have to pay to reimburse Plenary for the lost revenue while toll lanes are closed. The eastbound toll lane has been shut down since Friday. The westbound toll lane in the area will likely close Wednesday as CDOT shifts eastbound traffic through it to get the highway back open during repairs.

Under its contract with CDOT, Plenary can seek reimbursement of average toll revenue if the toll lanes have been temporarily suspended for more than 12 hours. CDOT couldn’t provide an estimate of an average day’s revenue in tolls by the time this article was published.

The company’s spokesman said it was too early to say whether Plenary would seek that sort of reimbursement.

RELATED: Ways to get from Boulder to Denver that aren't US 36 (because there's a huge crack in the road) 

“More importantly, we are working together to determine the safest and most efficient way to get traffic moving again, and ultimately make permanent repairs,” said Gil Rudawsky, spokesman for Plenary Roads, in a statement to 9NEWS. 

CDOT’s liability for lost toll revenue may all be a semantics issue.

“It appears how US 36 is closed matters,” said Danny Katz, state director of Colorado Public Research Interest Group, COPIRG, who analyzed the initial contract released by CDOT in 2014.

Katz said the contract doesn’t require reimbursement if the lanes are “temporarily ordered to be closed” by law enforcement, a semantic difference that will likely be key as both sides decide financial responsibility for the problem.

Eastbound lanes  on US 36 remained closed on Monday. CDOT said a temporary eastbound lane may open in the westbound toll lane as early as Wednesday. Repairs on the eroding section of highway could be lengthy.

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