A debate over balancing the need to honor the memory of Sept. 11 with the enormous costs of running a memorial and museum at ground zero has been reawakened on the eve of the attacks' 11th anniversary, as officials faced questions Monday over the project's expected $60 million-a-year operating budget and an agreement paving the way for the museum's completion was reached.

The number comes on top of the $700 million construction cost of the National September 11 Memorial & Museum. A report Sunday by The Associated Press noted that $12 million a year would be spent on security, more than the entire operating budgets of Gettysburg National Military Park and the monument that includes the USS Arizona Memorial at Pearl Harbor.

Mayor Michael Bloomberg, who leads the board of the nonprofit foundation that controls the museum and memorial, on Monday called the memorial's operating cost a necessity for security and other costs unique to hosting millions of visitors a year on the reborn site of two terror attacks, in 1993 and 2001.

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