Five Alberta road maintenance companies are asking the courts to determine whether the Alberta government broke its own rules and policies when it awarded a $482-million contract to a British Columbia firm.

In court documents filed last week, Volker Stevin Highways, Carmacks Maintenance Services, Alberta Highway Services, Ledcor Highways and LaPrairie Works allege the Alberta government "breached its obligations under several interprovincial trade agreements, Alberta statues, and its own published procurement policies."

The filings further allege the process wasn't "transparent" and the government was "unreasonable" and "unfair" and favoured Emcon over the interests of Alberta companies.

The contract represents a large amount of public money and warrants a closer examination by the courts, said Laurie Stretch, spokesperson for the companies.

"This group felt strongly enough that the minister's actions have been beyond what is acceptable in terms of procurement and fairness, that it was worth asking the courts for their view on it," said Stretch.

At issue is a road maintenance contract that had been handled by Carillion Canada, which was placed under creditor protection earlier this year.

Carillion handled about 40 per cent of Alberta's road maintenance, along with contracts in Ontario. A bankruptcy judge ruled last week that those contracts will now go to Emcon.

The Alberta companies had lobbied Transportation Minister Brian Mason for months, Stretch said.

They wanted Mason to lobby on their behalf and to change the terms of the Carillion asset sale, which stipulated that the Alberta and Ontario road maintenance contracts had to be sold together.

"We need Alberta companies to be able to have a role in this," Stretch said. "We would have liked to have seen the minister stand up for the Alberta marketplace."

Alberta Transportation spokesperson John Archer said Emcon was the only company that bid on the Carillion contracts, so that's the company the province negotiated with.

"In an effort to try get the best deal possible for Alberta taxpayers, we dealt with the bid that was on the table," said Archer.

United Conservative Party transportation critic Wayne Drysdale said in a statement he shares many concerns raised by the Alberta companies.

"So far, this entire process has lacked transparency and accountability," said Drysdale.

He called on Mason to disclose the terms of the contract with Emcon so Albertans can judge for themselves if the best interests of Albertans were met.

Nearly 500 full time and casual road maintenance employees represented by the Alberta Union of Provincial Employees reached their first collective agreement with Carillion in November 2017, just two months before the company was placed under bankruptcy protection.

Emcon has said it has agreed to increased staffing and honour the collective agreements now in place.