With 14 applications pending, the head of the Nuclear Regulatory Commission said Tuesday that a shortage of manpower at the agency may delay nuclear plant license renewals.Citing “resource limitations,” Gregory Jaczko warned it may take longer than expected to handle applications to extend the life of reactors. Bloomberg reported it was unclear which reactors would be affected, and Jaczko said the agency hasn’t made any decisions about how exactly staff limitations would affect the relicensing process.In at lease one case, at Entergy’s Pilgrim Plant, the NRC has said the plant can keep operating past the June 2012 expiration of its current license if the relicensing process is still pending. That license renewal application was filed in 2006.The NRC staff has grown substantially in the last decade, as the agency began reviewing applications for new plants and reactor designs, in addition to its work inspecting the nation’s 104 operating power reactors and other facilities. Between 2005 and 2010, the agency’s budget increased by more than 50 percent and its staff increased by more than 25 percent, Jaczko testified before a Senate committee last year. It has also moved into a new, 14-story headquarters in Rockville, Md. Its fiscal year 2009 budget was just under $1.05 billion and authorized the equivalent of 3,848 full-time positions. Most of that money comes from fees charged to licensees.Despite the staff crunch now being blamed for possible relicensing delays, the agency actually requested $26 million less in budget authority from Congress for fy 2012. In fact, a briefing on the proposed 2012 budget lists “reduced demand for licensing activities” as a reason for a $20.5 million decline in the “operating reactors” funding category.Nuclear plants with relicensing applications pending for one or more reactors include: Pilgrim, Indian Point, Crystal River, Diablo Canyon, Columbia, Seabrook, Davis-Besse, South Texas Project, Limerick and Grand Gulf.