Montana-Dakota Utilities Co. (Montana-Dakota), a Division of MDU Resources Group, is headquartered in Bismarck, ND. MDU Resources is a diversified natural resources company. Montana-Dakota is a retailer and producer of both natural gas and electricity.

The Montana-Dakota Lewis & Clark Station, commissioned in 1958, is located near Sidney, Montana. The lignite/gas fired power plant has nominal capacity of 50 MWe and is equipped with a first generation air quality control system (ACQS). The Lewis & Clark Station is base-loaded and burns more than 300,000 tons of lignite per year. It operates a tangentially fired boiler supplied by combustion engineering and is equipped with low NO_x burners. The primary system uses a mulitclone system for removal of the majority of fly ash. The secondary system consists of a flooded disc venture to further reduce particulate and SO_2.

New Mercury and Air Toxics Standards (MATS) regulations were passed in February 2012 requiring less than 0.03 lbs./MM BTU particulate emissions by March of 2015. Current particulate matter emissions at the Lewis & Clark Station do not meet these future MATS regulations.

AECOM Process Technologies (through legacy URS) was hired through an engineering, procurement, and construction (EPC) contractor to implement turning vanes, sieve trays, mist eliminators, and high performance spray nozzles within the stack in addition to replacing the existing oxidation air blowers and recycle pumps.