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Mineral-rich ocean mud stirs environmental fears

By Dan Nakaso

LAST UPDATED: 4:09 p.m. HST, Jul 6, 2011

Vast quantities of natural minerals necessary to produce everything from iPhones to electric cars to military weapons systems have been discovered across the Pacific by Japanese researchers, leading to concerns that a modern-day gold rush could contaminate waters around Hawaii.

Within months, U.S. scientists and researchers say, Japanese or other international interests could begin sucking up ocean floor mud rich in "rare-earth elements," extract desired minerals with acid and then send more than 90 percent of the acid-treated contents back into the sea.

"Collecting mud off of the bottom of the ocean and dumping it back will disperse it all over the water column," said University of Hawaii oceanography professor Eric De Carlo. "The environmentalists are just going to love this. They're going to cry bloody murder."

On Monday, Japanese researchers announced that they took 2,000 sediment samples from 78 sites as deep as 20,000 feet. Samples found near Hawaii had concentrations as high as 0.1 percent — a level greater than even rare-earth mines in China, the world's leader in rare-earth element production.

The Pacific Ocean sediment was full of heavier, more expensive rare-earth elements. And an area of 1 square kilometer near one site could meet one-fifth of the entire annual, worldwide demand for rare-earth elements, the researchers said.

Extracting the elements even from deep ocean mud would be easy, said scientist Yasuhiro Kato, a member of the research team.

"Sea mud can be brought up to ships, and we can extract rare earths right there using simple acid leaching," Kato told Reuters. Within a few hours "we can extract 80 to 90 percent of rare earths from the mud."

With 78 sample sites scattered around the eastern-south and central-north Pacific, it would be simple to avoid the 200-nautical-mile Exclusive Economic Zone that regulates U.S. environmental laws around Hawaii and U.S. territories and possessions, UH's De Carlo said.

He looked at a map produced by the Japanese research team and said the major sites appear to be well beyond 200 miles from Hawaii.

But Robert D. Harris, a lawyer and statewide director of the Sierra Club Hawaii Chapter, said, "I would plainly disagree with anyone who says there would be no environmental regulation. Hawaii's ocean resources are a billion-dollar resource that fuels most of our economy. We're critically concerned about anything that might damage our near-shore and offshore waters."

Environmental concerns have hobbled U.S. production of rare-earth elements, and China currently dominates the world market with 97 percent of the planet's production, increasing tensions with its neighbor, Japan.

"China has low labor costs and less stringent environmental restrictions," said Denny Roy, a senior fellow at the East-West Center. "The problem with rare-earth element production is that it's expensive, it's messy, it's environmentally problematic, it creates a lot of damage. The U.S. has moved from producing our deposits and has decided to let someone else do it. Because of cost and environmental concerns, that's how China ended up dominating production."

Until Monday's announcement, large-scale deposits had only been found on land, said Brad Van Gosen, a research geologist with the U.S. Geological Survey who studies rare-earth element deposits.

"Rare-earth concentrations on the ocean floor doesn't shock me," Van Gosen said. "But it's the first time somebody thought about analyzing ocean sediments for rare earths."

Base metals used for gold, copper, silver, lead and zinc have been discovered around undersea vents, so "rare earths on the sea floor make sense to me," Van Gosen said.

Media typically report 17 rare-earth elements found on the periodic table.

Van Gosen said there are really only 15 elements with atomic numbers 57 through 71, from lanthanum to lutetium, plus yttrium.

"Scandium is often called a rare-earth element, but technically itis not, and one of the rare earths — promethium — is created onlyin laboratory conditions," he said.

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