After extinguishing the metals fire that sent a huge plume of smoke into the air and prompted "shelter in place" alerts from several Peninsula cities, Redwood City announced the air quality alert/advisory has been lifted for residents living in south San Mateo County, Santa Clara County, and south Alameda County.
"Shelter in place" warnings for residents of Stanford University, Atherton, Menlo Park and Palo Alto have been lifted, according to authorities.
Redwood City police and fire departments lifted the "shelter in place" warning at 6:22 a.m. and Stanford lifted its warning at 6 a.m., according to the Stanford University Department of Public Safety.
The fire was reported at 1:21 p.m. at the metals-recycling plant located at 699 Seaport Blvd. in Redwood City.
There are no known injuries or fatalities from the fire, according to Redwood City.
Seaport Boulevard, which was closed overnight while firefighters worked to extinguish the blaze, has been reopened.
Several cities, including Palo Alto and Stanford, issued "shelter in place" warnings to residents as the fire burned throughout the afternoon and night. Menlo Park police issued the first of two warnings at 2:34 p.m., and Redwood City police issued an alert at 2:56 p.m. As the smoke blew further southwest, Palo Alto police issued a warning at 4:04 p.m. Stanford issued a warning at about 7 p.m.
Palo Alto and Stanford residents reported smelling rubber and metal odors throughout the evening.
The Bay Area Air Quality Management District is investigating the incident and U.S. Environmental Protection Agency has and emergency-response team on site, spokespersons for those agencies said.
Particulate matter -- fine particles of materials including smoke -- measured 2.5 microns yesterday and was at extremely high levels, said Lisa Fasano, spokesperson for the Bay Area Air Quality Management District, said on Monday morning.
Such small particles are of concern because they can't be seen and are breathed into the lungs and enter the bloodstream, she said.
The actual components of the particulate materials have not been identified, she said.
"Oftentimes -- and I don't know if it is the case in this matter -- the fires burn so hot that the materials get burned in the combustion of the fire. The bigger issue is that the particulate matter causes an immediate health risk," she said. Symptoms include difficulty breathing and respiratory distress, she added.
She said the smoke was trapped close to the ground because of an inversion layer, a weather occurrence in which temperature increases with elevation rather than the other way around.
Sims, which leases land from the Port of Redwood City, recycles scrap metal, cars, appliances and electronics, and calls itself the largest metals recycling company in the world.
In a statement, Sims Metal officials stated the facility is operational and open for business as of this morning.
The cause of the fire is under investigation.
The company stated that it has installed multiple fire hydrants and added and expanded fire lanes and fire access gates to the property in recent years. It also limited the height and quantity of stockpiled material.
Officials stated that the facility is designed to contain storm water, so none of the water used to fight the fire left the property.
"We always consider adopting additional corrective measures when recommended. We also engage in regular fire prevention training, and inspect our facilities on an ongoing basis, implementing corrective measures resulting from those inspections," officials stated.
Sims has had several fires at its facilities in recent years. The company has been cited for pollution problems at its Redwood City facility.
In April 2007, a large fire of burning crushed cars sent clouds of smoke over neighborhoods east of Hwy. 101 at the Sims site. The Bay Area Air Quality Management District cited Sims after residue (including toxic polychlorinated byphenyls, known as PCBs, and heavy metals) from the plant drifted into adjacent wetlands, according to an agency incident report.
In August of this year, Sims had a huge fire at its Jersey City, N.J., facility. The same location had a second fire early in October, according to various East Coast news reports.
The U.S. Environmental Protection Agency also halted loading of shredded materials onto container ships by the Redwood City facility in 2011, after inspectors found that PCBs, mercury, lead and other pollutants were spilling into San Francisco Bay, according to an EPA findings report and order.
Soils around the facility had high levels of heavy metals and other hazardous substances, EPA officials said at the time.