Social Responsibility
Mandan Refinery

It’s uncommon to find a refinery facility that has won national awards from the Nature Conservancy, the Wildlife Habitat Council, and the National Wildlife Federation, but that’s the case at Tesoro Petroleum’s refinery near Bismarck, North Dakota. Called the “North 40,” the refinery has dedicated about 640 acres of its property adjacent to the refinery’s process units and tank farm to serve as a natural wildlife habitat.

Originally constructed in 1972 as an engineered wetland for “polishing” treated wastewater, the area has been enhanced over the years to provide exceptional wildlife habitat. Of the 11 ponds within the wetland area, five are used for this wastewater treatment service. The remaining six ponds serve as waterfowl habitat and for emergency water storage. The facility was rededicated as the Bill Burns Nature and Wildlife Management Area in 1977.

Waterfowl aren’t the only beneficiaries of the forward-thinking refinery employees who built and maintain this system. Wild turkeys, pheasants, and the endangered Least Tern also call the area home. Nearly 200 different bird species have been sighted in the North 40 over the years. Deer, coyotes, fox and badgers also live and forage within its boundaries.

Employees at the Mandan refinery have enhanced the North 40 by building nesting structures and planting thousands of trees (including fruit trees) to provide cover and food for the refinery’s wild guests. In addition, portions of the property are planted with grain crops, alfalfa and grasses that provide feed and nesting straw. Excess portions of the annual harvest are donated to the Bismarck zoo to assist with its feeding program.