RockTenn, the Norcross-based consumer packaging company, said it will acquire Simpson Tacoma Kraft Paper Mill in Washington for about $343 million.

RockTenn is buying the West Coast mill from Simpson Lumber Co.. The mill makes various paper grades including containerboard, specialty kraft paper and pulp. Simpson Tacoma Kraft Paper Mill also sells electricity from a 55-megawatt fuel cogeneration facility.

RockTenn said it will invest $60 million in the mill over the next three years and it will supply Simpson Lumber with wood chips for seven years.

Chief Executive Officer Steve Voorhees called the acquisition a “great strategic fit” for the Norcross company. “Adding a West Coast mill will improve our ability to satisfy West Coast customers and generate significant operating efficiencies across our system,” Voorhees said in a statement announcing the deal.

Simpson Lumber plants include one in Meldrim, Ga., in Effingham County.