The U.S. Pacific Fleet said in a statement Wednesday that initial findings indicate all four sailors failed to adhere to standard navigation procedures at the time of the Jan. 17 grounding of the Guardian.
The sailors are the commanding officer, the executive officer and navigator, the assistant navigator and the officer of the deck. They've been reassigned.
Workers recently finished dismantling and removing the minesweeper from Tubbataha National Marine Park.
The park's superintendent has said the grounding damaged about 4,000 square meters, or nearly 5,000 square yards, of reef. The U.S. could face a fine of more than $2 million for the damage.