Local schools were closed and health officials suggested Tustin residents stay indoors after officials confirmed asbestos was found in ash and debris emanating from a fire that destroyed a massive and historic military hangar.
Orange County officials declared a local state of emergency Thursday night due to the danger posed by the air pollution from the fire, which besides asbestos, a carcinogen, was found to contain lead, arsenic, nickel and other heavy metals.
The pollution alert, from the South Coast Air Quality Management District came two days after a fire began to engulf one of two World War II-era hangars in the now-defunct Marine Corps Air Station in Tustin, sending large plumes of smoke into the air. Extensive portions collapsed as flames devoured the large, mostly wooden structure, which reached 17 stories high and 1,000 feet long.
Late Wednesday night, Tustin Unified School District Supt. Mark Johnson said that because of concerns about asbestos coming from the fire, school officials had decided to shut down local campuses. The decision came after a nighttime conference call with local agencies, including the AQMD, Johnson said in an email to parents, which was later posted on the district's website.
In the call, health officials confirmed debris in the area tested higher than 1% positive for asbestos.
"With student and staff safety being our highest priority and in collaboration with the City of Tustin and Orange County Health Care Agency (OCHCA), we made the decision to close all school campuses within Tustin Unified School District," Johnson wrote. "We apologize for the timing of this email and understand how this greatly impacts students, staff and family."
Schools will remain closed Friday in observance of the Veteran's Day holiday.
The decision to close schools came shortly after the AQMD confirmed late Wednesday in a news release the presence of asbestos near the fire.
"Samples of debris and ash were collected in public areas near the hangar, and results of laboratory testing show the presence of asbestos," the statement read.
Concerns about the air quality in the nearby community were raised shortly after the fire was first spotted early Tuesday.
On Thursday, U.S. Reps. Lou Correa (D-Santa Ana) and Young Kim (R-Anaheim Hills) asked in a letter to the Navy how it planned to clean the site and mitigate the impacts to the surrounding communities.
The letter, which was signed by other Democrat and Republican legislators, also asked the Navy's Base Realignment and Closure Coordinator Elizabeth Roddy what materials were used to construct the hangar, and what it planned to do with the site after the cleanup was completed.
"We are deeply concerned about the environmental impacts of this fire and about the release of pollutants in Tustin and the surrounding areas that could impact our constituents' health," the letter reads.
The letter was also signed by Republican and Democratic legislators, including Reps. Michelle Steel (R-Seal Beach), Katie Porter (D-Irvine), Linda T. Sanchez (D-Whittier), Mike Levin (D-San Juan Capistrano), Ken Calvert (R-Corona), Jay Obernolte (R-Big Bear Lake), Mike Garcia (R-Santa Clarita) and Raul Ruiz (D-Indio).
During the fire, smoke poured into the sky from the former military base near Warner Avenue and Armstrong Road, which was home to two hangars meant to house blimps during World War II.
The two hangars in the base housed helicopters and other weapons during the Korean War.
After the fire burned through the wooden structure for hours, firefighters with the Orange County Fire Authority announced they were pulling back personnel and letting the the structure burn because sections were collapsing, posing a risk for their firefighters.
To fight the fire, officials at one point deployed 11 engines, five other firetrucks and a Chinook helicopter that is normally used to fight brush fires.
On Wednesday, fire officials said little smoke was still visible, but smoke and ash could still pose a health risk to residents.
The Orange County Health Care Agency is asking residents to remain indoors, close doors and windows or "seek alternate shelter to reduce exposure to smoke and ash."
Residents are also advised not to touch any ash falling from the fire, and to immediately wash any of it off if it falls on their skin, eyes or mouth.
Parents are asked to wash their children's toys if they were dirtied with ash, and those who decide to go outside are advised to use N95 or P100 masks for protection.
On Thursday, county and city officials activated an Emergency Operations Center in response to the fire, air quality concerns, and cleanup of the incident. The center has also created a web page to provide the public updates on the fire and impacts.
This story originally appeared in Los Angeles Times.