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PITTSBURG, Calif. - A stubborn fire smoldering in Pittsburg and Bay Point has health officials telling people to stay indoors.
It's burning in largely inaccessible marshland, making fighting the fire a big challenge.
But the fire is not a threat at this point. Authorities said it's the smoke.
Pittsburg has been under a health advisory since Monday.
On Wednesday afternoon, the smell of smoke was strong at the marina where people were enjoying the outdoors.
Contra Costa Health Services is asking people to stay indoors as much as possible due to unhealthy and hazardous air quality at times.
These conditions are caused by the Marsh Fire that has been burning for more than six weeks.
"I had to come out to get some fresh air today," said Zabair Sadeek who lives in Pittsburg, But he acknowledged that "it's not too fresh" with smoke in the air and hazy skies.
"On a scale of 1 to 10, it's probably a 10-plus," said Pittsburg resident Johnice Claiborne. "It's that thick when you get outside."
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Elle Falahat of Danville said she drove to Pittsburg for a business meeting and noticed the smoke.
"The first thing I thought was my car was on fire," she said. "Then I got out, then realized I can't breathe. Then I noticed there's a fire."
Officials said no homes are threatened, but the smoke is raising health concerns.
"If they need to go outdoors, wearing a KN95 or N95 is their best choice," said Dr. Sara Levin, deputy health officer with Contra Costa Health Services. .
Levin said in addition to fixed monitors, hazmat teams are out in various locations to keep a close eye on the air.
They're advising people to keep their doors and windows closed.
"What's challenging is that it's shifting hour to hour given the wind and weather conditions," said Levin.
"It's unbearable. My kids don't even play outside during this time. We do indoor activities," Claibourne said.
Fire officials said they would normally let the fire burn itself out.
But given the many people affected by the smoke, they said that's not an acceptable option.
The fire started May 28 in a homeless encampment in Bay Point at a largely inaccessible marsh area and continues to smolder.
Officials said it's stubborn and nearly impossible to extinguish.
Contra Costa County Fire Protection District said it is working with regulatory agencies to come up with a plan to flood the area because traditional fire fighting methods have not worked.
Amber Lee is a reporter with KTVU. Email Amber at Amber.Lee@Fox.com or text/leave message at 510-599-3922. Follow her on Facebook @AmberKTVU, instagram @AmberKTVU or twitter @AmberKTVU