Heavy morning smoke expected to persist | TheUnion.com

Heavy morning smoke expected to persist

“Some smoke every day for the next week,” Sierra Air Quality Specialist Sam Longmire said.

As Cal Fire struggles to contain the Dixie Fire to the north and the Caldor Fire to the south, Nevada County residents find themselves enduring hazardous air quality.

Air Pollution Control Specialist Sam Longmire said the afternoon haze that replaced Monday morning’s heavy smoke is an air quality trend that will likely continue throughout the week in Nevada County.

“We’re looking at a pattern that will repeat tomorrow, the next day and possibly the remainder of the week,“ Longmire said.

The Northern Sierra Air Quality Management District specialist said the smoke yellowing the moon and reddening the sun is from both the Dixie and Caldor fires, but that the nine-day old Caldor Fire is hitting particularly thick.

“The smoke from the Caldor Fire is going to the northeast predominantly, but then in the evenings the smoke settles in the low areas,” Longmire said, adding that eastern Nevada County is recording higher smoke concentration than Grass Valley during the days.

Longmire said the air quality management district determined that Grass Valley’s blue and black oak-filtered air contained 112.0 micrograms per cubic meters of fine, particulate matter less than 2.5 microns across, making the air “unhealthy for sensitive individuals” at 4 p.m. Monday. Earlier that same day, Longmire said the air quality index reached 294 micrograms of particulate matter, which is considered “hazardous.”

“On Sunday morning we reached 355 micrograms of particulate per cubic meter,” Longmire said. “That’s more than 10 times federal standard, which is 35.


Longmire said those with chronic health issues should remain indoors as much as possible.

Truckee’s fir and pine-filtered air currently contains 241.0 micrograms per cubic meters of fine, particulate matter less than 2.5 microns across, making the region “very unhealthy.”

Over the last three weeks, Cal Fire has increased the Dixie Fire’s containment by 17%, bringing the containment up to 40%. Even so, the fire continues to rage across five counties — Butte, Lassen, Plumas, Shasta and Tehama — yellowing blue skies to the southeast. The Dixie Fire has burned 725,821 acres over 40 days.

To the south, the Caldor Fire in El Dorado County has burned 106,562 acres over nine days, with only 5% containment.

Longmire said the forecast predicts a slight chance of mountain rain via thunderstorms this coming Sunday and Monday, but “it’s hard to predict that far out.”

Longmire said his wish for wind is contingent on fires being under control, but a good breeze would improve dispersion and give Nevada County residents some relief.

“Smoke is a very small particle, and there are other things in smoke,” Longmire said as he explained the consequences of long-term smoke exposure, like inconsistent heart function and damaged organ tissue. “You’re basically bringing all those chemicals into your lungs. Over time, it’s sort of like smokers of cigarettes, the more impurities are that get in their lungs leads to all sorts of health problems.”

“This is the worst year we’ve had in the last 10 years,” Longmire said. “We’ve had more days over the federal standard than any day since before 2010.“

Longmire said he only remembers the air being worse in 2008, with the lightning siege that resulted in a 4,000-acre fire no one noticed for days in Plumas County.

“Plumas County is worse this year, though,” Longmire said.

Longmire said people who are especially sensitive to smoke might benefit from wearing an N95 mask outdoors.

“The cloth masks help a little bit because you can smell the smoke less, ” Longmire surmised. “They must be doing something.”

Longmire also encouraged people to consider the coldest part of their homes in winter, and seal those areas off from smoke seepage.

“Those are the rooms that will keep smoke,” Longmire said. “Block off bottoms of doors.”

Rebecca O’Neil is a staff writer with The Union. She can be reached at roneil@theunion.com

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