Sailor Dead After USS San Francisco Mishap

One sailor aboard the nuclear attack submarine USS San Francisco has died from injuries suffered when the boat reportedly went "aground." His name is being withheld. Another 23 crew members are being treated for injuries.

Okay, someone please tell me how a submarine goes "aground" in water that's miles deep. A prudent individual would have suspect that at least one other vessel is limping back to port somewhere, also having run "aground" in the water south of Guam. As a point of reference, it has to be noted that the deepest part of all the world's oceans, the Marianas Trench, is south of Guam. It's seven miles deep and it's guaranteed that the USS San Francisco didn't bump bottom in the neighborhood of the Marianas Trench.