SAN DIEGO -- The Navy has concluded that it would have been dangerous to stop an underwater training blast believed to have killed three or four dolphins last month off San Diego Bay.
Navy divers monitored the area for marine mammals for more than 90 minutes on March 4 before placing a charge on the ocean floor, the 3rd Fleet public affairs office said Monday.
"All the training procedures were followed," said Lt. Beth Teach. "The divers were qualified."
Ten minutes into a 15-minute countdown, observers spotted dolphins approaching the area where the charge had been placed on the ocean bottom.
To stop the detonation, commanders could have sent divers back to the ocean floor or pulled the device to the surface to try and separate the detonators from the main charge.
"The officer in charge determined that either option would place Navy personnel in grave danger and had an extremely low chance of success due to the short time frame," the statement said.
As a last resort, the commanders placed their boat between the dolphins and the detonation site in an attempt to head off the pod, but the effort was unsuccessful.
Three dead dolphins were recovered at the site of the explosion. The carcass of another was found three days later near Ocean Beach. The carcasses were turned over to the National Marine Fisheries Service, Teach said. She didn't know if necropsies were performed.
"The Navy recognizes the need to do the investigation," Teach said.
But no blame was assigned for the deaths and there will be no disciplinary action taken.
The Navy suspended time-delay undersea detonation training in the San Diego area. Teach didn't know when the ban would be lifted.
The explosions are part of the Navy's ongoing underwater warfare training.