Gregory Jaczko will soon be gone as chairman of the federal Nuclear Regulatory Commission, and his departure can’t come too soon. Mr. Jaczko’s leadership of the NRC has been characterized by arrogance, duplicity and a willingness to use the agency for political ends in regard to nuclear waste disposal.

Mr. Jaczko was instrumental in carrying out the administration’s decision to close the waste site at Yucca Mountain, Nev., which had been in the works for 30 years at a cost of $15 billion. It was closed largely for the political benefit of Senate Majority Leader Harry Reid, D-Nev., who opposed the project and who faced a tough re-election fight in 2010.

No surprise, the NRC will get another opponent of the Yucca Mountain repository in Mr. Jaczko’s stead.

Despite that, nominee Allison Macfarlane should be a step up for the agency if only because there is so much room for improvement at the helm.

Last December, Mr. Jaczko’s fellow comissioners — two Republicans and two Democrats — publicly chastised him as a bully whose relentless management style threatened the agency’s program.

He was criticized for creating a hostile work environment, particularly for women at the agency.

Mr. Jaczko often found himself on the losing end of 4-1 votes, most recently as the NRC approved new commercial nuclear plants for Georgia and South Carolina.

Scientists at the agency told a congressional committee that he had effectively trampled on years of work in nuclear waste management in the hurried closure of the Yucca project.

An NRC inspector general concluded last year that Mr. Jaczko kept his fellow commissioners in the dark on the Yucca project.

South Carolina and Washington State, home of the Hanford defense facility, have challenged its closure in court. So has Aiken County, home of the Savannah River Site.

Mr. Jaczko, in contrast, said last week that the NRC was “one of the best places to work in the federal government during my tenure” and described his three years as chairman as “incredibly productive.”

The last word on Mr. Jaczko’s record is expected soon in a follow-up report by the NRC inspector general, who is completing a year-long investigation of the chairman.

Ms. Macfarlane, meanwhile, believes that nuclear waste can be safely contained at existing reactor sites around the nation for decades to come.

Presumably, that includes the Savannah River Site, which has become more deeply entrenched in its role as the de facto storage facility for defense waste during the Obama administration.

She should get some pointed questions about her views on the long-term use of SRS for storage and waste processing from South Carolina and Georgia senators during her confirmation hearings next month. SRS already has been used for that purpose for decades, with no apparent end in sight.