American Crystal Sugar is offering a 13 percent raise over 5 years, with 4 percent and 3 percent respectively in the first two years. The rest would be divided evenly over the next three years.

Union workers would be transferred to a company health plan. The union says costs out-of-pocket costs will more than double. The company says the health care cost increase is significantly less than the proposed pay increase.

The proposal includes new "management rights" language giving the company more power on workplace governance. This includes the erosion of union seniority rights for promotions and, the union says, an increased ability to contract out work to non-union workers.

Note: The original contract offer workers rejected in July 2011 included a $2,000 signing bonus. That bonus was not included in subsequent offers.