KITTERY – In a continuing effort to keep the Portsmouth Naval Shipyard open, New Hampshire and Maine congressional delegations Thursday took a closed-door tour of the yard with Navy Secretary Gordon England.

Calling it a “delightful visit,” England said he liked what he saw, praising the operation’s “lean manufacturing approach” and strong relationship among workers and managers.

“A lot of what they’re doing, they’re exporting to other places, which tells me that they’re in a leadership role,” he said.

Despite his praise, England cannot guarantee that the base will remain open.

“We have a fiscal responsibility to the taxpayers to do what’s right,” he said, “and we also have a responsibility to the Navy.” England said no bases are exempt from the Base Realignment and Closure process.

The delegations presented a bipartisan front in their effort to keep the 204-year-old shipyard, the Navy’s oldest, open for its 4,300 employees from New Hampshire, Maine and Massachusetts. The workers maintain nuclear submarines.

Republican Sens. Judd Gregg and John Sununu New Hampshire, and Republican Sens. Olympia Snowe and Susan Collins of Maine joined New Hampshire Rep. Jeb Bradley and Maine Rep. Tom Allen, the one Democrat, on the tour.

They were joined later by Republican Gov. Craig Benson of New Hampshire and Maine Democratic Gov. John Baldacci.

The yard sits on Seavey Island in the Piscataqua River that separates New Hampshire and Maine.

England does not have the final say in which bases remain open, but Snowe said the point of the visit was for England to get a chance to talk to workers and see for himself how the yard works.

She compared the closure process to “playing Russian roulette.” She said the delegations cannot let up in their efforts to make sure the yard stays open.

The key, she said, “is to remain very aggressive.”

Earlier this year, the Seacoast Shipyard Association, a local group, secured $100,000 from New Hampshire and Maine to hire a lobbyist to promote the cause in Washington.

A Base Realignment and Closure list to be released May 16, 2005, could signal the end for nearly a quarter of the nation’s 425 military bases. Defense Secretary Donald Rumsfeld has said that closing some domestic bases could save $13 billion in seven years.

Earlier this year, a Senate vote narrowly defeated a measure that would have delayed decisions on domestic base closures until plans on overseas bases were completed.

Lawmakers who supported the proposal said they were worried that troops being sent home from overseas bases would have nowhere to go if domestic bases closed early.