Dakota Gasification Company 1

Dakota Gasification Company’s Great Plains Synfuels Plant Concept started in early 1970s Plant built by a consortium of five pipeline companies Construction began in 1981 Synthetic Natural Gas (SNG) production began in 1984 The plant was built by a consortium of pipeline companies with financial backing from the government because of the fear of an energy shortage in the 1970’s. Construction began in 1981 and was completed in 1984. Due to falling natural gas prices, in 1985 the consortium made the decision to abandon the plant and turn operation over to the Department of Energy. DOE operated the facility for 3 years before selling to Basin Electric Power Cooperative. Basin Electric created Dakota Gasification Company to operate the facility. 2

A new owner….DGC A technological marvel but not a financial success… Original Owners Default The original investors defaulted on August 1, 1985, about one year after first gas was put in the pipeline, due to the very low price of natural gas. DOE Operation Period The DOE operated the plant from 1985 until 1988 Sold to Basin Electric Power Cooperative Basin Electric purchased the plant from the DOE & formed DGC, a wholly owned subsidiary to operate the facility. 3

DGC’s Great Plains Synfuels Plant A Unique Facility Only commercial coal gasification facility producing synthetic natural gas Coproducts sales of anhydrous ammonia, liquid nitrogen, & sulfur Diversification of products began in 1989 with initial $25 million for capital projects for phenol/cresylic acid & xenon/krypton Installation of flue gas desulfurization project to produce DakSul45 in 1996 1100 ton/day Anhydrous Ammonia Plant completed in 1997 Carbon Dioxide (CO2) Pipeline for Enhanced Oil Recovery (EOR) in 2000 4

Great Plains Synfuels Plant Process Flow 5

Committed to Health, Safety & the Environment Environmentally Compliant Enhanced Plant Efficiencies Adopted ACC’s Responsible Care Policy 2007 6

The Environment Ambient air is monitored continuously at four sites for SO2 & NOX Groundwater is monitored at more than 100 wells Reduced CO2 emissions by 49% since 2000 thru carbon capture and sequestration activities Ammonium Sulfate – an environmentally friendly product BNSF Railway 2009 Product Stewardship Award Surrounding communities outreach Reverse 911 system DGC operates four sites that continuously monitor ambient air quality in the surrounding area for sulfur dioxide and nitrogen dioxide concentrations. The sites are located within 5 miles of the plant in all four directions. Over the years, these monitoring stations have recorded concentrations that are well below the EPA standards. DGC monitors more than 100 groundwater monitoring wells through the plant and on adjacent property. The plant is a zero discharge facility for process water. The synfuels plant reduces its emissions and produces a valuable product at the same time. Sulfur scrubbed from the flue gas is turned into ammonium sulfate fertilizer. In 2007, DGC was awarded the Burlington Northern Santa Fe Railway Product Stewardship Award to saafe handling and movement of rail cars carrying hazardous materials with no non-accidental releases. As part of the Risk Management Program, DGC meets annually with area citizens to discuss DGC programs in place to protect the public, to share information and take questions that the public may have about the plant and its operations. Annually, community leaders are invited to the plant site to learn more about DGC and its recent activities. 7

Coproducts Carbon Dioxide Anhydrous Ammonia Naphtha Natural Gas Liquid Nitrogen Krypton/Xenon Ammonium Sulfate Cresylic Acid Phenols 8

240 mmscf/d Pipeline capacity DGC and CO2 Weyburn and Midale, Saskatchewan 19 Million Tons Sequestered To Date Compressors 240 mmscf/d Pipeline capacity CO2 CO2 PIPELINE Current flow rate: 153 mmscf/d World’s Largest Carbon Capture and Sequestration Project 9

DGC’s CO2 Pipeline 205 miles Featured on the History Channel’s “Modern Marvels” 14” & 12” carbon steel pipe Strategically routed through Williston Basin oil fields Pipeline take offs already installed 10

Xenon/Krypton Gases Capacity to produce 3.1 million liters annually Used high-intensity halogen lighting, lasers & thermal pane windows Krypton: 89% Xenon: 7.7% O2/Argon: 3.3% 11

Liquid Nitrogen Capacity to produce 24 million gallons annually Used for food processing refrigeration, as an oil well additive and in artificial insemination, chemical processes, & medical procedures Product specification 99.99% 12

Phenol Capacity to produce 33 million lbs annually Fleet of 34 railcars Used in: Plywood/OSB/Insulation Countertops/Overlays/Exterior Siding DVDs/CDs Automotive Parts Caprolactum-Nylon 6 Circuit Boards Pharmaceuticals Purity: >99.9% 13

Cresylic Acid Mixture of cresols & xylenols Capacity of 33 million pounds annually Used in: Pesticides/Insecticides Antioxidants/Vitamin E Wire enamel coatings Dyes/Solvents Pyrethroids Automotive Parts Semiconductor materials Electronic chips Alkylphenols Resins Fleet of 48 Railcars Useful Cresylics >94% 14

Naphtha Capacity of 7 million gallons annually Fleet of 25 railcars Used as a gasoline blend stock, in making paint thinner & other solvents & feedstock for benzene, toluene, & xylenes 15

Anhydrous Ammonia Capacity to produce 400,000 tons annually Fleet of 223 railcars Truck loading facility Fertilizer for farming & as chemical feedstock 16

Ammonium Sulfate Created to utilize the sulfur oxide removed from the plant boiler steam in order to be compliant with the Clean Air Act of 1990 DGC’s flue gas desulfurization unit is removing 93% of the sulfur Capacity to produce 60,000 tons annually On site storage for 40,000 tons Fleet of 25 railcars Truck loading facility Ammonia: 21% as N Sulfur: 24% as S 17

Great Plains Synfuels Plant Today Work Force: more than 700 people Coal Usage: ≈ 18,000 tons daily Daily Production Capacity: 170 mmscfd SNG, along with many coproducts Annual Plant Loading Factor: 90-92% Reduced CO2 emissions by 49% since 2000 The current capacity is greater than at the time of acquisition. 18

Questions? 19