VANCOUVER -- A mining company that has hired hundreds of temporary workers from China for its northern B.C. coal mine advertised those jobs in Canada for $10 to $17 less than what is paid for similar work at a nearby mine, a lawyer representing two unions told a federal court judge on Friday.

HD Mining also advertised specifically for workers who speak Mandarin, Charles Gordon said in arguing for the unions' interest in taking the decision to grant those permits to court.

"Bringing in up to 300 temporary foreign workers at wage rates considerably below what has been bargained by the trade unions at an immediately adjacent mine will invariably erode the union's bargaining power, and thus its ability to negotiate better terms and conditions of employment for its members at that mine."

Those jobs are not available to members, Gordon said.

"This directly affects the union as a union," he argued.

There is also a public interest in the outcome of a review, Gordon said.

Permits have been granted under the federal Temporary Foreign Worker Program to between 200 and 300 Chinese workers to conduct preliminary work at HD Mining International Ltd.'s Murray River mine near Tumbler Ridge, B.C. The company has said it was not able to find workers in Canada with the necessary specialized skills.

The unions want the court to examine hundreds of Labour Market Opinions rendered by the federal Human Resources and Skills Development, which concluded the jobs could not be filled by Canadian workers.

The Murray River mine is awaiting an environmental assessment and has not yet been approved.

An estimated 17 temporary workers have already arrived at the site, court heard, and another 60 are slated to arrive in mid-December.

The International Union of Operating Engineers Local 115 and the Construction and Specialized Workers Union Local 1611 want the court to declare the permits invalid and issue an injunction against any further permits for HD Mining until the court matter is resolved.

Lawyers for the Crown said the unions should not be granted standing in the case.

To do so would set a precedent that would open "floodgates" for labour and interest groups to pursue reviews of government decisions.

"That would be turning the entire judicial review process on its head," Lorne Lachance, representing the federal Department of Justice, told the judge.

"Is the court to be used for fishing expeditions that go well beyond individual concerns?" asked Lachance.

"There's fish in the lake," Judge Douglas Campbell responded.

Even Human Resources Minister Diane Finley has said there may be problems in the process, the judge noted, referring to Finley's announcement last week that concerns about the Murray River mine prompted a review of the entire foreign worker program.

"We need to see the process. We need to know what HD did," Campbell said. "This was all done behind closed doors."

The judge adjourned the case until Tuesday to give the two parties a chance to see if they can resolve the issue of standing by agreement.

HD Mining Ltd. is a partnership between China-based Huiyong Holding Group, which owns a 55 per cent stake, and Canadian Dehua International Mines Group Inc.

The B.C. government is looking into allegations recruiters in China asked potential applicants for fees, which is illegal under provincial law.