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Phase 2 of wildfire cleanup efforts are underway in Los Angeles. Thousands of sites have been cleared of hazardous materials like solvents and lithium-ion batteries. Attention now turns to clearing debris, like wood, metal and ash. But there's a problem - a major rainstorm is on the way. Jacob Margolis from member station LAist reports.
JACOB MARGOLIS, BYLINE: The National Weather Service says the rainstorm is expected to arrive on Wednesday and last until Friday. But it's Thursday afternoon that's the period of greatest concern because that's when more than half an inch of rain could fall in one hour - enough to trigger debris flows in recently burned areas. Ariel Cohen is a meteorologist with the NWS and warned of the storm at a press conference on Tuesday.
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ARIEL COHEN: Given the elevated chances for significant debris flows consisting of raging torrents of rockslides and mudslides that can be damaging and even deadly, now is the time to start getting prepared for these potentially dangerous conditions.
MARGOLIS: There could be other hazards as well. Even after light rain last month, there may still be lead, arsenic and other heavy metals in ash at burn sites. That's according to researchers at the University of Southern California, who have been doing initial testing. When rains fall, heavy metals can percolate deeper into soils on properties and can get carried with all sorts of other junk into sewers and out into the ocean. Annelisa Moe is the associate director of science and policy at Heal the Bay, an environmental nonprofit.
ANNELISA MOE: Each time that it rains, at least for the next several months, we're going to see spikes in these contaminants again.
MARGOLIS: Her organization is taking regular water samples. Just recently, she was on the coast after the first rainstorm since the fires.
MOE: It really looked like chocolate milk with, you know, chunks of fire debris, like ash in it, and a really persistent brownish foam that indicates higher presence of nutrients.
MARGOLIS: Those nutrients, which can come from burning vegetation, feed algae and can lead to algal blooms, which can be toxic to seabirds and marine mammals like sea lions. And the heavy metals can enter the food web and make seafood less safe to eat. It'll take some time for researchers to know the full impact of these fires on California soils and waterways.
For NPR News, I'm Jacob Margolis in Los Angeles.
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