Commitments and Contingencies

3 Months Ended

Mar. 31, 2017

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Commitments and Contingencies - MGE Energy and MGE.

a. Environmental.

MGE Energy and MGE are subject to frequently changing local, state, and federal regulations concerning air quality, water quality, land use, threatened and endangered species, hazardous materials handling, and solid waste disposal. These regulations affect the manner in which they conduct their operations, the costs of those operations, as well as capital and operating expenditures. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Regulatory initiatives, proposed rules, and court challenges to adopted rules, have the potential to have a material effect on our capital expenditures and operating costs. Management believes compliance costs will be recovered in future rates based on previous treatment of environmental compliance projects. These initiatives, proposed rules, and court challenges include:

• The EPA's published water effluent limitations guidelines and standards for steam electric power plants, which focus on the reduction of metals and other pollutants in wastewater from new and existing power plants, such as the coal-burning plants at Columbia and the Elm Road Units.

• The EPA's cooling water intake rules, which require cooling water intake structures at electric power plants, such as our WCCF, Blount, and Columbia plants, meet best available technology standards so that mortality from entrainment (drawing aquatic life into a plant's cooling system) and impingement (trapping aquatic life on screens) are reduced.

• Greenhouse Gas (GHG) reduction guidelines and approval criteria established under the Clean Air Act for states to use in developing plans to control GHG emissions from existing fossil fuel-fired electric generating units (EGUs) and systems. Implementation of the rule is expected to have a direct impact on existing coal and natural gas fired generating units, including possible changes in dispatch and additional operating costs. Given the pending legal proceedings, the nature and timing of any final requirements is subject to uncertainty. If the rule remains substantially in its present form, it is expected to have a material impact on MGE.

• Federal and state air quality regulations impose restrictions on various emissions including emissions of sulfur dioxide (SO₂), nitrogen dioxides (NO₂), and other pollutants, and may require permits for operation of emission sources.

• The EPA's rule to regulate ambient levels of a pollutant through the Ozone National Ambient Air Quality Standards (NAAQS). The State of Wisconsin has joined a lawsuit filed by several states challenging the EPA's new ozone standard, alleging that the new standard is not attainable and the EPA is not properly considering background levels in setting its ozone attainment levels. Oral arguments in this case are scheduled to begin in mid-2017. MGE will continue to monitor the EPA's progress on attainment designations and related litigation to assess potential impacts at our facilities, particularly our Elm Road Units.

• Rules regulating nitrogen oxide (NO_x) and SO₂ emissions including the Cross State Air Pollution Rule (CSAPR) and Clean Air Visibility Rule (CAVR). At this time, regulatory obligations, compliance strategies, and costs remain uncertain due to the continued legal challenges surrounding CSAPR and CAVR.

• The EPA's Coal Combustion Residuals Rule, which regulates coal ash as a solid waste, and defines what ash use activities would be considered generally exempt beneficial reuse of coal ash. The rule also regulates landfills, ash ponds, and other surface impoundments for coal combustion residuals by regulating their design, location, monitoring, and operation. Review of our Elm Road Units has indicated that the costs to comply with this rule are not expected to be significant. Columbia's operator has developed a preliminary implementation schedule for meeting the various deadlines spelled out in the rule. Costs at Columbia will be dependent on what is determined during the evaluation stage.

The matters in the bullet points above are discussed further in Footnote 17.c. in the Financial Statements of MGE Energy's and MGE's 2016 Annual Report on Form 10-K.

b. Legal Matters.

MGE is involved in various legal matters that are being defended and handled in the normal course of business. MGE maintains accruals for such costs that are probable of being incurred and subject to reasonable estimation. The accrued amount for these matters is not material to the financial statements. MGE does not expect the resolution of these matters to have a material adverse effect on its consolidated results of operations, financial condition, or cash flows.