RICHMOND, Calif. -- A mothballed guided-missile cruiser that has been parked in the Suisun Bay since it was decommissioned in 1994 prepared for its final voyage out of the San Francisco Bay Thursday, headed west to a naval exercise in the waters off Hawaii where it will be torpedoed and sunk.

The U.S.S. Horne, its deck and sides rusted with age, sat at a dockside in Richmond awaiting a tow boat that was scheduled to move it out later in the day.

It had been berthed at the dock to allow divers and salvage crews remove any material that would present an environment threat once it is sent to the bottom of the sea during Sunday’s multi-national exercise involving armed forces from the U.S., South Korea, Australia, Canada, Chile, Japan, Netherlands, Peru, Singapore and the United Kingdom.

Aside from its anchorage as part of the ghost fleet in Suisun Bay, the Horne has a Bay Area connection in that it was built at the Hunter’s Point Naval Shipyard. The guided-missile frigate was commissioned in April 1967 and served in the Vietnam and Gulf War among other assignments.

While the ship’s final voyage may be bittersweet to many of those who served on her, the departure of the Horne was a positive sign for environmentalists who m the ghost fleet is an ongoing threat to the waters of the Suisun Bay.

Several environmental groups have sued the federal government over toxic pollution caused by a fleet.

The groups have accused the U.S. Maritime Administration of violating state and federal environmental regulations as dozens of decaying ships linger well past a congressional deadline ordering their removal.

"These vessels have long since ceased being useful for transportation and are now just floating junkyards," according to the complaint brought by the Natural Resources Defense Council, Arc Ecology and San Francisco Baykeeper.

More than 70 ships comprise the Suisun Bay Reserve Fleet, some dating back to World War II. The old ships were once kept afloat in case of war, but many have fallen into disrepair, overtaken by rust and rot.

A congressional order set a 2006 deadline to scrap more than 50 ships, but a regulatory quagmire has kept the fleet anchored in place in the shallow, brackish inland waters east of San Francisco Bay.

Before they can be scrapped and sold, Coast Guard regulations require the removal of barnacles and other sea creatures clinging to the obsolete ships' hulls. That process causes toxic paint to flake off into the water. Fear of contamination has delayed their disposal.