A German automaker plans to return to Alaska's North Slope early next year to continue its secretive cold-weather performance tests on cars.

Audi last winter hired a contractor to build a frozen track on the tundra outside Deadhorse — an industrial hub for the Slope oil fields — to test acceleration, anti-lock braking and other vehicle systems on the ice.

The effort is unusual. Ice roads in the region usually support oil field operators or local villagers hauling new vehicles and other supplies from the cities.

But the company secured a five-year permit from the state early this year to run the winter tests in the nation's northernmost region, where temperatures typically plunge below zero for months at a time. The multiyear program will pump $6 million into the Alaska economy while employing 25 people for tests, according to the company's application.

Last year, the contractor planned to conduct tests on a 2.74-acre circular track on land leased by oil company BP.

But a denning grizzly bear was found within a half-mile of the area, forcing Audi to run the tests elsewhere outside Deadhorse to comply with state requirements, said Sean Willison, who helped review the permit for the Alaska Department of Natural Resources. The new testing site was located on leased land controlled by another oil company, Hilcorp.

Audi is expected to return to the Slope in January, he said.

The company already operates an 80-employee winter facility in Fairbanks, but wanted to expand the testing to the north, according to its application. Privacy is an issue: the company requested a publicly closed testing area.

The application says the research involves "proprietary and sensitive internal material and technology."

Carmakers typically like to keep secret their future designs and features.

Audi spokesman Mark Clothier said Tuesday he could not provide details about the tests.

Public safety is also a factor as the company analyzes the performance of its cars.