The Ekati diamond mine presented its "last and final offer" to striking workers Tuesday, offering them signing bonuses to go back to work —and the right not to belong to a union.

Ekati managers presented the offer to union negotiators at talks in Edmonton. It offers the workers an average four per cent wage increase this year and next, a $1,000 bonus to return to work, and a lump-sum bonus for workers to remain at Ekati until the end of 2006. That bonus could amount to as much as eight per cent of a salary for northerners, and four per cent for non-northern workers, the company said.

"We expect the union will take it to our employees for a vote," said Richard Morland, Ekati's vice-president of operations, in a company news release.

The Ekati offer includes more days off for personal leave, and paid sick leave. The offer also says that employees will continue to be eligible to earn incentive pay "for great teamwork and reaching safety and performance goals."

About 375 Public Service Alliance of Canada employees walked off the job at the diamond mine on April 7 to pressure the company for a first contract. Wages, benefits, and seniority were among the issues.

On Friday the company rejected a union offer to settle the strike.

Union membership optional?

While the union says the picket line has remained firm, the company has claimed up to 40 per cent of PSAC unionized workers have crossed the line and returned to work. The latest offer also presents workers with the option of not joining the union.

"This is not about Ekati versus the union, as BHP operates many successful unionized operations around the world," said Morland.

"However, in this dispute a large portion of the bargaining unit elected to report for work and not support the job action. As such, we felt it critical that to be acceptable to a majority of employees, our offer had to expressly recognize the right to choose."

The offer also says new unionized workers will be offered a defined contribution plan, rather than a defined benefits plan.

Ekati was recently chastised by the Canada Industrial Relations Board for trying to convert employees' pension plans to a defined contribution plan without consultation. It was ordered to restore those employees to a defined benefits plan.

The company says its offer also protects the company's northern access and benefits agreements with local aboriginal governments.

About 2,000 people work at the Ekati diamond mine, located about 300 kilometres north of Yellowknife.