The U.S. Supreme Court is slated to hear arguments Wednesday on whether costs must be considered before the U.S. Environmental Protection Agency issues new rules on limiting mercury and other pollution at electric power stations.
A ruling could have a major impact on Dominion Resources, which gets almost half of its power from coal-fired power plants and has complained that new EPA rules will stick ratepayers and the utility with higher costs.
The EPA spent about two decades preparing new rules on limiting mercury from air pollution. The new rules were announced in 2012 and are due to go into effect in April. Utilities and other energy firms have sued to block the rules and force the EPA to consider the cost of issuing new regulations in its deliberations.
How the high court rules could affect another set of EPA rules that seek to limit carbon emissions that contribute to climate change. Those rules were proposed last summer and the EPA is seeking comment before deciding on final versions later this year.
Dominion was so concerned about the impact of the carbon rules that it convinced the General Assembly this year to freeze some of its rates and forego rate reviews for five years. Some analysts believe that implementing the new carbon rules as stated in their draft form could cost Dominion ratepayers from $5 billion to $6 billion over the next decade or so.
The Richmond utility insists that the new carbon rules could force closure of some of its six coal-fired power stations. Coal plants are the largest single emitter of carbon pollution.
Dominion’s single largest carbon polluter -- the largest single air polluter in the state -- is its 1,600-megawatt Chesterfield power station near the intersection of Interstate 95 and Route 288 south of downtown Richmond.
Environmentalists believe that the effects of the new carbon rules won't be so severe because Dominion already announced plans to shut down some coal-fired stations that date to the 1950s and has converted others to natural gas.