The Obama administration is preparing for the release of a series of energy regulations over the coming weeks in advance of a Republican-controlled Congress next year that will prompt pushback from industries and lawmakers, testing President Barack Obama’s commitment to his environmental agenda.

On Wednesday, the Environmental Protection Agency proposed lower limits for ground-level ozone, or smog, in the atmosphere, setting off a nearly yearlong regulatory process for setting a new standard. Public-health and environmental groups say the limits are essential in preventing a range of respiratory diseases. Businesses say it could be the costliest regulation in U.S. history.

By year’s end, the administration plans to release at least three other regulations, including another from EPA regulating coal ash, a byproduct of coal-fired electricity, and two from the Interior Department setting standards for Arctic oil and natural gas drilling and hydraulic fracturing on federal lands.

The EPA also is expected to decide sometime in December to what extent it will regulate emissions of methane, a potent greenhouse gas that is inadvertently emitted during the production and transmission of natural gas. In January, the agency intends to issue a final rule controlling carbon emissions from new power plants, a precursor to the agency’s parallel standard cutting carbon from power plants already in operation, which EPA plans to complete next summer.

Driven by various factors, including court-enforced deadlines and presidential directives, the initiatives will touch on a broad swath of the economy, especially the utility, oil and natural gas industries. It also advances an ambitious environmental and climate-change agenda Mr. Obama hopes to make a legacy of his time in the White House.

Republicans on Capitol Hill, who will control both chambers of Congress next year, have vowed to pass legislation to slow down or stop altogether several EPA rules, including the ozone standard announced this week, which could force Mr. Obama’s consider vetoing bills handcuffing his top priorities.

“The Obama Administration hasn’t even fully implemented—or seen the consequences of—existing rules, yet here we see another effort to slow job growth and send jobs overseas,” Senate Minority Leader Mitch McConnell (R., Ky.), said in a written statement after the ozone announcement. “The new Congress will review the rule and take appropriate action.”

The EPA’s ozone proposal would limit ozone between 65 and 70 parts per billion in the air and sought comment on a standard as strict as 60 parts per billion, in line with what an independent scientific advisory panel recommended earlier this year. The current level, established in 2008 by the George W. Bush administration, is set at 75 parts per billion, though some regions of the country still aren’t complying with the 1997 level set at 84 parts per billion. The agency said it will take comment on keeping the standard at the current level, something industry groups have encouraged.

“When it comes to reducing this pollution, we’ve done it before and we’re on track to do it again,” EPA Administrator Gina McCarthy said in a call with reporters.

The agency is relying on the Clean Air Act, a 44-year-old law Congress first passed in 1970, for the ozone rule and several other air-pollution standards, including the proposed climate rules and a mercury regulation the Supreme Court on Tuesday said it would review over its costs.

“This administration is relying very heavily on what Congress has already told us is our job,” Ms. McCarthy said.

The EPA estimates the cost to businesses and localities to meet the ozone standard would range between $3 billion and $15 billion in 2025, a decade from now, and the monetary value of the public health benefits range between $6.4 billion and $19 billion in 2025.

These estimates are significantly less than what the EPA proposed in 2011, when it said costs could reach $90 billion and public-health benefits could reach $100 billion. Ms. McCarthy said an improvement in air quality brought by regulations the agency has pursued in recent years has brought down the estimated costs of this latest ozone proposal. The part of the Clean Air Act the EPA uses to issue ozone limits says the agency only can consider science, not cost, an approach supported unanimously by the Supreme Court in 2001.

“Because of recent federal pollution-control rules reducing ozone-causing pollutants—which I have consistently supported—our air is significantly cleaner and healthier,” Sen. Lamar Alexander (R., Tenn.) said. “It may be wiser to let these existing rules continue to make our air cleaner and then let’s see whether stricter ozone standards for communities, like the one proposed today, are really needed.”

The ozone standard, which the Clean Air Act mandates to be reviewed every five years, isn’t a direct regulation on business. States, however, must comply, which in turn would compel utilities, factories, refineries and other businesses and municipalities that emit smog-forming pollution, including nitrogen oxides and volatile organic compounds, to install new pollution equipment.

The agency is expected to issue a final standard by October of next year, a timeline the EPA said on its website Wednesday it intends to meet. However, the administration hasn’t completed writing the plan for states to comply with the standard set early by the Bush administration.

via EPA Proposes Stricter Ozone Air Pollution Standard – WSJ.