Olivier Merindol was named president of the River Region for the Cement Division of Lafarge North America. One of the company's five North American regions, the River Region comprises all or part of 15 states in the midwestern United States.

Merindol joined Lafarge in 1996 at its global technical laboratories in Lyon, France. He later served at the company's technical center for Central Europe in Vienna, Austria. For the past five years, he was senior vice president in charge of Lafarge's Corporate Technical Services Center in Montreal, which provides testing services and product research for all of Lafarge's cement operations in North America.

John Stull, the departing president of the region, has been named senior vice president for marketing and supply chain management for Lafarge's global cement business. As president, Stull was responsible for successfully integrating the former Blue Circle operations into the region. He also oversaw the renovation of the company's Sugar Creek, Mo., plant, largely regarded as one of the most environmentally advanced cement plants in the world.