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View Full Version : The Salton Sea: a time-bomb amid California drought



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18th April 2015, 06:46 AM
https://www.youtube.com/watch?v=G6YChIV61qo

A Shrinking Sea Mean Toxic Dust
By Gary Polakovic
The Press-Enterprise

A shrinking Salton Sea could expose its toxic-coated bottom to wind storms, posing a major air pollution hazard for eastern Riverside County and the Imperial Valley, officials say.

The Salton Sea is expected to fall from 3 to 20 feet in coming years because of rapid evaporation and increased water conservation. The shoreline would recede by up to several miles, leaving at least 21,120 acres of sediments to the mercy of hot, dry winds.

"It may be creating a problem Southern California cannot live with," said Phil Meyer, former consultant to the Salton Sea Task Force, a coalition of government agencies dedicated to finding ways to cleanse the sea.

Salton Sea mud contains enough arsenic and selenium to qualify for disposal in a dump reserved for the most toxic of society's trash. Chromium, zinc, lead and pesticides, including DDT, are also in the lake bottom.

"These chemicals could attach themselves to the fine particles of sediment when the lake evaporates and could be breathed by people...It could potentially be a health hazard," said Tom Gill, geochemist for the air quality branch of the Crocker Nuclear Laboratory at the University of California, Davis.

The Salton Sea, the largest lake in California, encompasses about 380 square miles. It rests in one of the driest places in the nation. Gale-force winds are not uncommon. Given those conditions, tons of dust blown from the Salton Sea bed could significantly worsen visibility in the already hazy Coachella Valley, explained Mel Zeldin, particle pollution coordinator for the South Coast Air Quality management District.

Indio at the north end of the Salton Sea already experiences some of the nation's worst particle air pollution. Dust from sand storms accounts for 70 percent of the haze in the Coachella Valley, according to the South Coast district.

The district and the state Air Resources Board, working with the U.S. Fish and Wildlife Service, are planning a $14,000 study to examine the chemical makeup of the lake floor and the dangers if the substances become airborne.

Dried up lakes can be enormous polluters.

The highest amount of tiny, airborne particles recorded in the Western Hemisphere occurred at Keeler, Calif., on Feb. 3, 1989. Wind-driven dust from the desiccated Owens Lake bed pushed particle concentrations to 1,861 micrograms per cubic meter -- 12 times greater than the federal health-based limit. Five percent of all the particle pollution in North America comes from the Owens Lake bed, Gill said.

Arsenic in dust blown from the shores of shrinking Mono Lake in the eastern Sierra Nevada poses a cancer risk of 1 in 10,000 -- 100 times more dangerous than the toxic emissions from a large factory. Arsenic is a byproduct of volcanic activity in the area, Gill said.

Dust from the banks of the disappearing Aral Sea in the former Soviet Union is one of the world's great environmental health hazards.

Once the fourth largest lake in the world, massive river diversions have shrunk the Aral Sea by 40 percent, exposing about 11,000 square miles of lake bottom. About 40 million tons of dust, salts, pesticides and hydrocarbons are swept up by dust storms annually, causing mouth and respiratory cancers among the 5 million people living near the sea.

"There's no reason to believe it couldn't or wouldn't happen at the Salton Sea," Gill said.
http://www.sci.sdsu.edu/salton/ShrinkingSeaNToxicDust.html