The B.C. mining company that hired more than 200 Chinese workers for its coal mine in northeastern B.C. says it could lose millions if the Federal Court rules to revoke the foreign worker permits.

"If there is a delay to this project, we have outlined the impacts and costs of damages," HD Mining vice-president Jody Shimkus told CBC News. "And that ranges from the hundreds of thousands, to millions of dollars depending on the length of the delay."

HD Mining hired workers from China to do sample work at its Murray River underground coal mine near Tumbler Ridge, and 17 have already arrived. The company said there were no qualified Canadians who could carry out the specialized work at the underground mine.

But two unions are in court challenging the work permits obtained by HD Mining, asking for an injunction to prevent the arrival of 60 more miners this weekend.

The B.C. Federation of Labour said documents show HD Mining's previously unreleased transition plan outlines how the company won't start hiring Canadian miners for more than four years and plans to continue using temporary foreign workers for the next 14 years.