WASHINGTON — The Portsmouth Naval Shipyard in Kittery could face closure again if the Obama administration wins congressional support for a new round of military base closings.

But the yard’s vulnerability was the subject of sharp disagreement Thursday among defense analysts and members of Congress from Maine and New Hampshire.

While Maine lawmakers said the facility is too valuable to close, one analyst said it’s a potential target because there will be less work in the future on the nuclear submarines it overhauls.

“Portsmouth’s days are probably numbered if there is a rigorous and comprehensive review of bases,” said Loren Thompson of the Lexington Institute, a think tank in the Washington area.

Defense Secretary Leon Panetta and other officials outlined a plan Thursday for absorbing $487 billion in military spending cuts. Although the plan leans heavily on reductions in ground forces and delays in the introduction of new weapons systems, it includes a provision for President Obama to seek congressional support for a new round of domestic base closures.

It’s unclear when the president might submit that request and what the focus and projected savings from a closure program might be. Any action in this election year is seen as unlikely.

The Portsmouth Naval Shipyard was on the Defense Department’s base closure list in 2005, but that recommendation was overturned by the independent Base Realignment and Closure Commission. The panel’s chair said then that Portsmouth was “the gold standard by which we should measure shipyards.”

The round of base closures in 2005 did claim the Brunswick Naval Air Station, which is now being redeveloped for commercial use.

Shipyard employees, businesses and public officials campaigned fiercely to keep the Kittery yard open, joining forces in a group known as the Seacoast Shipyard Association.

Neil Rolde of York, the association’s president, said Thursday that supporters of the shipyard are prepared to do battle again, if necessary.

“We are not shaking in our boots,” Rolde said. “We are just gearing up to fight the good fight all over again.”

A spokesman for the shipyard did not respond to a request for comment.

U.S. senators from Maine and New Hampshire issued a joint statement Thursday, saying they want to show that the two delegations and the region will work together to stave off any threat.

The commission’s decision in 2005 to keep the shipyard open showed that “the Portsmouth Naval Shipyard remains a fundamental and irreplaceable component of our nation’s security,” said the statement by Sens. Olympia Snowe and Susan Collins of Maine and Kelly Ayotte and Jeanne Shaheen of New Hampshire.

About 4,600 civilians and 96 military personnel work at the shipyard on the Maine-New Hampshire border. The work at the Kittery shipyard, one of four remaining Navy shipyards, mainly involves overhauling Los Angeles-class nuclear submarines.

The Seacoast Shipyard Association, in its most recent economic impact study, said that in 2010 Portsmouth’s civilian payroll totaled more than $395 million. The yard also bought nearly $45 million worth of supplies and services, with more $6.3 million of that spent in Maine, the study showed.

U.S. Rep. Chellie Pingree of Maine, a member of the House Armed Services Committee, said the shipyard should not have to fear for its survival. Pingree, a Democrat, noted that the only other Navy shipyard that does comparable submarine work is in Hawaii.

“(Portsmouth) is one of the most efficient shipyards in the country and is absolutely essential in maintaining the Navy’s submarine fleet,” Pingree said in an email. “There is absolutely no reason why it should even be considered for closure.”

Thompson, the defense analyst, said he agrees that the shipyard “is a very well run place,” but the submarines it refuels and refits are beginning to be retired and replaced by Virginia-class submarines, which don’t need midlife refueling.

There is other maintenance and overhaul work, but the Pentagon has said it is shifting more submarines to the Pacific, which could make the Kittery yard less vital, Thompson said.

“There was serious consideration to closing Portsmouth in the last round of base closures,” he said. “This time around the case for closing will be much more persuasive.”

Whether Congress will approve a round of base closures remains to be seen, analysts say.

Todd Harrison, a senior fellow at the Center for Strategic and Budgetary Assessments in Washington, noted that base closures carry significant up-front costs. He said taxpayers spent about $30 billion over six years to carry out the 2005 base closures. That means that in the short run, other defense cuts would have to be found to offset base closure costs, he said.

The Maine and New Hampshire senators said in their statement that the 2005 base closure costs will take a decade to recoup completely.

“Another proposed round of … closures now doesn’t make sense for our national defense or our national finances,” the senators said. “The (Defense) Department is in the midst of decisions on our posture overseas, including the possibility of withdrawing forces and closing bases in Europe, and any move to close bases here in the U.S. should not be entertained until that process is concluded.”

MaineToday Media Washington Bureau Chief Jonathan Riskind can be contacted at 791-6280 or at:

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