BISMARCK, N.D. (AP) — Dakota Gasification Co. is moving forward with plans to add a $402 million urea fertilizer production facility at its Great Plains Synfuels Plant in western North Dakota.

The board of directors for the Bismarck-based company approved the move this week. The board in October 2012 launched a study of the idea, and it wrapped up about three months ago.

Urea is a granular fertilizer used by farmers. It requires anhydrous ammonia and carbon dioxide, both of which are produced at the synfuels plant that turns coal into natural gas for distribution in the eastern U.S.

Urea will be the 10th co-product manufactured at the plant, which also makes two other fertilizers — ammonia and ammonium sulfate.

"We are happy to build on the fertilizer products we already manufacture, and believe the addition of urea will bring more benefit to the agricultural community," Paul Sukut, Dakota Gasification interim chief executive officer and general manager, said in a statement.

The new facility also will produce diesel emission fluid — the 11th co-product — which can be used to meet a federal government mandate to reduce pollution from diesel engines. The company will build a 1.1 million gallon storage tank for the fluid.

The urea facility is scheduled to be finished in early 2017 and will produce 1,100 tons of the fertilizer daily.

Dakota Gasification is a subsidiary of Bismarck-based Basin Electric Power Cooperative, which generates and transmits electricity to 137 rural electric systems in nine states.