A memorial to honor the 129 men lost aboard the USS Thresher (SSN-593) has received the final approval needed to be built on the grounds of Arlington National Cemetery in Virginia.

Because the cemetery is controlled by the Department of the Army, the memorial needed the secretary of the Army's approval, which it has received, the memorial committee announced Monday.

The submarine was lost on April 10, 1963, while conducting deep dive exercises 220 miles off of Cape Cod. Among the 129 men killed were residents of New London, Groton, Norwich, Gales Ferry, Mystic, Uncasville and Jewett City.

The Navy has said the disaster likely was caused by a leak in the boat's engine room, which led to the nuclear reactor shutting down. The sub sank below its crush depth and imploded.

The Navy responded by accelerating safety improvements and creating a program called "SUBSAFE," an extensive series of design modifications, training and other improvements. No submarine certified under the program has been lost since.

The USS Thresher ANC Memorial Foundation has raised about $60,000 in private donations to build the monument, which is expected to cost about $5,000. The remainder of the money will be used to cover any other costs that arise after the memorial is erected.

For more information visit threshermemorial.org.

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