A proposed requirement that U.S. nuclear power plants add $20 million devices to prevent radiation leaks, one of the costliest recommendations stemming from meltdowns in Japan two years ago, has attracted a flurry of last-minute lobbying.

The U.S. nuclear industry opposes the rule, which would require almost a third of the nation’s reactors to install a special filter on vents designed to prevent an explosive buildup of gases. Xcel Energy Inc., the Minneapolis-based utility that serves 1.2 million Minnesota electric customers, said it doesn’t support the proposed rule, which would apply to its Monticello, Minn., reactor.

The staff of the U.S. Nuclear Regulatory Commission recommended in November that the radiation-scrubbing filters be required on 31 aging reactors. The commission itself is now voting on the proposal, a process that is expected to conclude in coming days just as the second anniversary of the triple meltdown at Japan’s Fukushima Daiichi plant nears.

“I would encourage you to resist outside pressure to disregard the expert recommendations of your staff,” Rep. Paul Tonko, D-N.Y., told the five NRC members at a House Energy and Commerce Subcommittee hearing in Washington last week. “To the public, there is no such thing as a small nuclear accident.”

Exelon Corp. of Chicago, which owns more U.S. reactors than any other company, Entergy Corp. of New Orleans, Duke Energy Corp. of Charlotte, N.C., and Southern Co. of Atlanta are among companies with units that would need the filters. Major filter suppliers include Areva SA of Paris and Westinghouse Electric Co., a unit of Tokyo-based Toshiba Corp.

“Safety gains should be significant enough to outweigh additional costs” as the agency considers ordering plant upgrades, Rep. John Shimkus, R-Ill., said at the hearing.

Supporters of the measure say it is overdue and consistent with what the rest of the world is doing.

Japan requiring vents

Japan announced last year that filtered vents will be required on its reactors. Other nations that use or are considering filtered venting systems on their reactors include Germany, Taiwan, Spain, Switzerland, Finland, Sweden, France and the Netherlands, according to the NRC.

“The tens of millions of Americans who live near the affected reactors located in 15 states should not face additional delays,” a dozen Democratic senators led by Barbara Boxer of California and Ron Wyden of Oregon wrote in a Feb. 20 letter to NRC Chairwoman Allison Macfarlane.

Macfarlane took office in July, and the filter decision will be her first on Fukushima-related regulations. “If we think a particular rule or regulation is required for adequate protection of a facility, then we do not account for cost,” Macfarlane said in an interview with Bloomberg. She declined to discuss the filter rule specifically, other than to say the commissioners are voting.

The industry already faces decisions about investing in costly upgrades or simply retiring aging plants that are in competition with cheaper natural gas. Germany said it would shutter its atomic plants by 2022.

‘Wrong starting point’

The costs associated with adding filters are “not overwhelming in the grand scheme of things” for utilities, said Julien Dumoulin-Smith, an analyst at UBS Securities in New York. But the additional costs would add “insult to injury” for an industry in a difficult economic environment, he said.

The industry prefers a plant-by-plant approach to the question of whether filters are necessary.

“Ordering the installation of passive, engineered filtered venting systems is the wrong starting point to provide greater protection of public safety and the environment,” Anthony Pietrangelo, chief nuclear officer of the Nuclear Energy Institute, a trade group of reactor owners, wrote to the NRC in January. “Any containment failure would bypass the external filter, rendering it ineffective.”

Xcel, in a statement, said it supported the industry’s position because the regulation should “specify the results to be achieved rather than the methods used.” Xcel’s other two reactors at the Prairie Island nuclear power plant near Red Wing would not be affected by the proposed rule.

Margaret Harding, a nuclear-industry consultant based in Wilmington, N.C., said it would be better for the NRC to define the acceptable limit of emissions from the vents and allow the industry to determine the best way to achieve that goal.

“Every single reactor out there is a little bit different,” she said.

The proposed changes would affect so-called Mark I and Mark II containments that house boiling-water reactors. These General Electric Co.-designed units are similar to those that were destroyed by a tsunami at Fukushima.

The filters are built to capture radioactive materials before they are released into the atmosphere during an emergency. They are installed on vents that resemble smokestacks and can be opened to release hydrogen, which under pressure can cause explosions.

In Germany, such filters are installed already at venting systems in all of the country’s nine operating nuclear reactors,

Nicolas Wendler, a spokesman for the German Atomic Forum, said that equipping venting systems with filters “makes absolute sense” to prevent radioactive contamination from spreading in case of an accident.

No U.S. boiling-water reactor has ever had to use its venting system, and the benefits of filtering vents don’t outweigh the costs, according to the NEI. Most filtering should take place inside reactor containment buildings before additional devices are installed elsewhere at a power plant, the group has said.


Staff writer David Shaffer contributed to this report.