REDWOOD CITY -- Authorities said it was safe to be outside after firefighters finished putting out a billowing metal-yard fire that spread an acrid metal-plastic smell over the Bay Area, renewing attention on an auto-recycling plant with a history of reprimands for polluting.
A large stockpile of crushed cars and other metal debris caught fire about 1:30 p.m. Sunday at Sims Metal Management at 699 Seaport Blvd., burning into the night and warranting a close eye until Monday morning, when it was fully stamped out by a squad of more than 50 firefighters from throughout San Mateo County.
No one was reported injured by the smoke or fire, which was limited to a debris pile about 900 square feet in area and 30 feet tall. But the noxious odor produced by the blaze was detected as far south as South San Jose and across the bay in Oakland and Berkeley.
The company's recycling facilities in Hayward and San Francisco experienced fires in 2009 and 2010 respectively, according to records from the Bay Area Air Quality Management District. Across the country, its Jersey City, N.J., plants saw notable fires this past August and October.
Soot and other particles from Sunday's fire in Redwood City are expected to linger as light winds combine with cold surface temperatures to trap dirty air and keep it from dissipating, which is the same reason the air-quality district endorses wood-burning bans during the winter months.
"It's going to take a while before it clears out," district spokeswoman Lisa Fasano said.
At its peak around 6 p.m. Sunday, soot saturated the surrounding air at a volume of 114 parts per million, more than three times the 35 ppm limit set by federal health standards. While the brunt of the air impact wafted over Redwood City, the cities of Palo Alto and Stanford also issued "shelter in place" alerts telling residents to stay indoors, especially those with existing respiratory ailments.
The concentration fell below federal limits by midnight, but the smell of the materials continued to be noticed well into Monday morning, even as those shelter advisories were lifted.
A cause for the fire remains under investigation, but it is believed to have been accidental, said Jim Palisi, fire marshal for the Redwood City-San Carlos Fire Department. Palisi lauded the practices at the Sims yard, such as keeping stockpiles distant enough from each other to prevent a fire from easily spreading. The metal yard re-opened Monday morning.
"It's a delicate operation," Palisi said. "Like any recycling center, there are a lot of moving parts, machinery, a lot of cutting and grinding, creating friction and heat."
At its 13-acre bay front site in Redwood City, Sims shreds about 300,000 automobiles a year, along with appliances and other metal products, and loads the materials via huge conveyor belts onto ships bound for China, Korea and other countries, where they are made into new products.
A statement from the New York City-based firm -- which bills itself as the largest metal recycling company in the world -- echoed similar thoughts, touting the installation of multiple fire hydrants and limits on the height of stockpiled materials.
That might have been at least partly influenced by an April 2007 fire at the same yard that similarly sent a huge cloud black smoke over the Peninsula, resulting in a $20,000 fine from the air-quality district. Last year, the Redwood City plant was reprimanded by the Environmental Protection Agency based on findings that a high level of toxic pollutants from the metal shredding ended up in nearby soil and sediment, prompting pledges from company officials to comply with the federal agency.
In 2011, the U.S. Fish and Wildlife Service sent Sims a letter stating that fibrous residue from the auto shredding that "may contain plastics, rubber foam, residual metal pieces" and other waste was regularly blowing, or being washed, 800 feet across the water from the Sims site and contaminated Bair Island, which is part of the San Francisco Bay National Wildlife Refuge.
Sims could not be reached for further comment Monday.
Contact Robert Salonga at 408-920-5002. Follow him at Twitter.com/robertsalonga.