Officials say the fire started just before 3 p.m. at Sims Metal in the 600 block of Seaport Blvd.
SKY7 was over the scene where fire crews could be seen battling the blaze from several sides.
Redwood City fire officials say although the fire is out, it did send off a huge plume of smoke for several hours that has now drifted into other areas.
Santa Clara County Fire issued an advisory on X warning those sensitive to smoke should remain indoors if possible.
ABC7 News meteorologist Sandhya Patel is tracking the smoke and says it is now impacting air quality. Sandhya says Purple Air is showing declining air around parts of the Peninsula and South Bay.
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The Bay Area Air Quality Management District says inspectors are investigating this fire.
Sims Metal has had previous issues with fires at their Bay Area facilities. In 2018, there was a blaze at the company's Richmond plant where authorities were forced to issue a shelter-in-place for nearby neighborhoods due to the toxic smoke.
RELATED: Firefighters battle toxic smoke from Richmond scrap metal fire
As for the Redwood City facility, in 2022, California's Department of Toxic Substances Control ordered Sims Metal to determine the extent of its toxic pollution and clean it up. These include potential toxic releases from the past and any impacts from a fire that occurred at the facility in March 2022.
Sims Metal Management, located off U.S. Highway 101 near the Redwood Creek, receives, recycles and exports scrap metal from local suppliers and businesses.
The state department reportedly found elevated levels of lead, zinc and cadmium at the site in addition to a buildup of light fibrous material, which are produced during the metal shredding process, at or near the facility between 2012 and 2019. Without proper management, light fibrous materials can be "uncontrollably dispersed offsite due to wind, rain, or other factors," according to the state's order.
Given the facility's proximity to homes, parks, schools, a trail and parts of a wildlife refuge, the state is concerned about health impacts to nearby populations.
The Bay City News Service contributed to this article.