Unemployment may be rising nationally, but record coal prices are prompting unprecedented steps by big nonunion operators to avoid crippling miner shortages.

Richmond, Virginia-based Massey Energy struggled with voluntary turnover topping 20 percent during a 2005-2006 price spike. The nation's fourth-largest producer credits three-year guaranteed contracts for individual miners with helping to cut the rate to 14.8 percent this year.

With coal prices more than doubling since 2007, other companies say they're mulling incentives too.

But United Mine Workers spokesman Phil Smith calls individual contracts "yellow dog" deals that harken to the 1920s when operators ran roughshod over miners. Smith calls a union contract the best way to guarantee a stable work force.