PARTICULATE matter 10, or PM-10, is dust. It is sometimes called "respirable particulate matter," indicating that it is fine enough to be inhaled. "You breathe this dust in, but you don't breathe it out," writes Karen Piper, in "Left in the Dust: How Race and Politics Created a Human and Environmental Tragedy in L.A."
Piper is a native of Ridgecrest, Calif., the first city downwind of Owens Lake, a 110-square-mile dry lake covered in PM-10; she likens it to "a giant bowl of fresh talcum powder." As a child, she saw dust clouds that "hung in the air like fog" and days when "the sun disappeared and it was hard to breathe." \o7 \f7
For The Record
Los Angeles Times Friday August 18, 2006 Home Edition Main News Part A Page 2 National Desk 2 inches; 115 words Type of Material: Correction
Owens Lake dust: In the July 23 Book Review, a review of the book "Left in the Dust" said incorrectly that when L.A. Aqueduct water was diverted in 2001 to control dust, "for the first time since farmers dynamited the aqueduct in 1927, water flowed into the Owens Valley." The reference should have been to Owens Dry Lake: It was the first time since 1927 that water had been diverted into the lake, except for storm overflows. The channel is 233 miles long, not 223 as stated, and not all the land it traverses is owned by Los Angeles' water agency, as the review said. A majority of it is owned by the U.S. government.
For The Record
Los Angeles Times Sunday August 20, 2006 Home Edition Book Review Part R Page 10 Features Desk 3 inches; 111 words Type of Material: Correction
Owens Lake dust: A July 23 review of the book "Left in the Dust" said incorrectly that when L.A. Aqueduct water was diverted in 2001 to control dust, "for the first time since farmers dynamited the aqueduct in 1927, water flowed into the Owens Valley." The reference should have been to Owens Dry Lake: It was the first time since 1927 that water had been diverted into the lake, except for storm overflows. The channel is 233 miles long, not 223 as stated, and not all the land it traverses is owned by Los Angeles' water agency, as the review said. A majority of it is owned by the U.S. government.
Like asbestos, PM-10 infiltrates lung tissue, causing and exacerbating respiratory illnesses and autoimmune reactions. PM-10 is also called fugitive dust, a name that implies it has outwitted human efforts to contain it. \o7 \f7
Construction, industry, agriculture and cars' tailpipes all create, stir up or emit PM-10. Because of the significant adverse health and environmental effects, the U.S. Environmental Protection Agency sets air quality standards for acceptable levels of PM-10, and the state Health and Safety Code sets the laws governing its prevention and mitigation. Developers grading the landscape to make way for tract homes and industrial parks must have a water truck spraying down the dust behind every piece of equipment that scrapes at the earth. When the Santa Ana winds kick up, a man on the nightshift at Santa Anita Park circles and circles the dirt racetrack with a water truck.
What settles dust is the weight of water. The Owens Lake dust once was covered in brine, populated by tule grass and salt shrimp and traversed by steamboats. When the Los Angeles Aqueduct began diverting the lake's water in 1913, arsenic, cadmium, nickel and other naturally occurring toxic metals were left concentrated in the dry dirt. The Sierra Nevada range that borders the valley acts as a funnel: Wind lifts the dust and carries it in ominous opaque clouds, south through the Owens Valley, through Piper's hometown, across the high desert and toward Los Angeles.
The dry Owens Lake is the largest source of PM-10 pollution in the United States, according to the Great Basin Unified Air Pollution Control District, the air quality district for three High Sierra counties. To see the dry lake for yourself, you could take Highway 395 north from Los Angeles County, along the eastern side of the Sierras. Or you could follow the 223-mile-long aqueduct, but that would be trespassing -- the land around it is owned by Los Angeles' Department of Water and Power.
