Abdul-Mutakallim, who had never descended below 90 feet in scuba gear, testified later that he and Reyher realized the dangers of making the dive — hazardous conditions and not much air.

It was high risk for low reward, he said at a Navy investigative hearing convened before Hanna.

A dozen or so divers from the salvage unit had arrived at Aberdeen the day before, Feb. 25, to undergo final evaluation after several months of training.

If all went well, they could be deployed in April.

But the Army had closed the pond after the death of its diver the previous month. And Army officials did not know why the Navy divers had come to Aberdeen, according to Hanna’s investigate report.

After discussions, the Army granted permission for the evaluation to proceed the next day.

According to the Navy report, on Feb. 26, the Navy divers were briefed about Lazzaro’s death.

He had been one of four scuba divers who had descended in two-man teams to 127 feet to help retrieve a weight that had been used in the December anti-mine test, the Army said in a recent report on his death.

That dive was supposed to be brief, about 10 minutes, to prevent the need for a decompression stop on the way back up. The divers had a wireless communications link to the surface and to each other.

They had worked on the weight and were headed back when, at about 60 feet, Lazzaro shouted that he was losing air. Another diver told him to “blow and go,” meaning surface immediately, despite the risk of decompression sickness caused by rapid ascent.

Seconds later, Lazzaro popped to the surface and tore off his diving mask. Someone yelled, asking if he was okay. “No!” he replied, then sank again.

It was hours before they found his body in 53 feet of dark water and hauled it to the surface with a rope.

The Army report, which blacked out the cause of the accident for public release, said Lazzaro had fatal air bubbles in his lungs, heart, brain and blood vessels from his abrupt ascent. He was pronounced dead at a hospital.

No more bubbles

In February, the air and water were colder, the Navy dive was to be deeper, but the outcome would be the same.

At first, the idea of using scuba gear was rejected because, as the divers knew, it left little margin for error. Plus, the Navy’s normal scuba working limit was 130 feet.

“Not a good idea,” one diving supervisor said. “Do the math.”

A third option was to make the dive with air supplied from the surface through hoses.

But Runkle, the unit’s commander, had urged his men to “train like we fight,” be aggressive and make more deep scuba dives, the Navy report said.

One of the evaluators suggested that the divers reconsider scuba. The dive was short. There was a recompression chamber on hand. And the divers would be tethered to each other and to the surface.