Divers remove all ammunition from Pyramid Lake

Information from: Reno Gazette-Journal

FALLON, Nevada (12 June 2005) -- Working by feel in pitch darkness on the bottom of Pyramid Lake, U.S. Navy divers have completed the removal of rockets and ammunition submerged since World War II.

Since early May, divers have removed more than 13 tons of munitions — including more than 240 rockets and 182 crates of large-caliber ammunition — dumped in the lake north of Reno by the Navy between 1944 and 1946.

"We have recovered every known piece of ordnance in the lake," said Senior Chief Daniel Gross, who described the operation as one of the most difficult in his 19 years as a Navy diver and ordnance disposal expert.

"It was very challenging," said Gross, 41. "Some of the stuff you just couldn't predict, but it couldn't have come off any better."

Rockets, 20 mm shells and 50-caliber tracer rounds were left in Pyramid Lake after the Navy abandoned a 76-acre torpedo and bombing range near Sutcliffe.

The three-year project to recover the sunken munitions was a cooperative effort between the Navy and Pyramid Lake Paiute Tribe.

Tribal officials said they are glad to be rid of the stuff, which the Navy destroyed last weekend at Fallon Naval Air Station.

"The tribe just wanted closure with that era," said Gerry Emm, the tribe's environmental director. "This is an end to something a lot of people didn't even realize had happened."

Tribal Chairman Norm Harry agreed.

"It's a big relief for the tribe knowing the cleanup is final," Harry said. "It's important to get it out."

The location of the submerged ordnance was determined through sonar and the use of remote-controlled submersible vehicles.

Diving began last summer, with some ordnance removed then. The bulk of the rockets, shells and bullets were pulled from the bottom this year in May and early June.

The task was difficult and dangerous. Divers worked at depths of as much as 222 feet below the surface. At Pyramid Lake's altitude of about 4,000 feet above sea level, that's the equivalent of about 270 feet deep in the ocean, Gross said.

Such a depth meant divers could only stay on the bottom a maximum of 15 minutes withouts risking potentially fatal decompression sickness. Then they had to spend 70 minutes coming slowly back to the surface, stopping four times to decompress gases built up in their bodies.

The water was cold, at times 38 degrees on the bottom. And visibility of only a few feet was quickly reduced to zero when bottom sediment was stirred up by working divers.

Divers were guided to rockets and crates of ammunition by a sonar operator stationed on a barge at the surface.

"It was 'swim forward, move right, move right, move forward,'" Gross said. "There was no light at all at that depth.

"(Visibility) was zero. It's all by feel."

The project marked the first time the crew's particular type of re-breathing scuba gear was used at high-altitude, Gross said. Cases of dangerous decompression sickness were not only possible, but expected.

One tense moment came when a surfacing diver "blew to the surface" too quickly when his dry suit expanded like a balloon. He was rushed to the shore and a waiting recompression chamber, where he underwent five hours of treatment, Gross said. The diver was uninjured.

The Pyramid Lake mission was Gross' last as a Navy diver. He retires in two weeks.

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SOURCE - Reno Gazette-Journal