People from Northeast Pennsylvania have first-hand knowledge of what happens when coal producers and utilities don't bear a cost for pollution: they pollute. The region still faces challenges left by the anthracite industry, which despoiled the region with scant government interference, took its money and went home.

Today in Washington, President Obama will announce carbon emission standards that will mark an historic advance for environmental regulation and air quality. The regulations drafted by the Environmental Protection Agency will mandate a national 20 percent reduction in carbon dioxide emissions over the next six years. Since older coal-fired power plants are the primary emitters of CO2, the regulations likely will have the greatest impact on those operations.

There likely will be political opposition and litigation from the coal and power industries. But it is interesting to note that the proposal is based largely on policy established by Mitt Romney, the 2012 Republican presidential nominee, when he was governor of Massachusetts. His environmental secretary at the time was Gina McCarthy, the current EPA administrator.

Ms. McCarthy has not divulged the specific regulations but has said that they provide state governments with broad flexibility to meet the standards. State governments will have one year to submit a compliance plan for EPA approval.

Pennsylvania already is headed in the right direction. Its abundant natural gas already has supplanted a great deal of coal-fired power generation as a matter of economics rather than environmental regulation. And it has the potential to effect greater energy efficiency at many levels, and to increase the statewide mix of fuels for power generation and vehicles.

Because Pennsylvania is downwind from many coal-fired power plants in other states, the new regulatory regime will have vast benefits for public health.

The state government should embrace the initiative and develop an innovative plan for compliance, using its natural resources, research institutions and a commitment to leave behind its history of industrial pollution.