Smog blows in from California

Tuesday, May 18, 2004 | 9:37 a.m.

Smog from California apparently is being blown into the Las Vegas Valley, threatening Southern Nevada with a third unhealthy day for ozone this year, air quality officials said today.

In addition, the wind kicked up dust to high levels at 5 a.m. today, posing the possibility of a third unhealthy dust day this year.

If unhealthy levels are reached, it would be the first day this year with two pollutants exceeding federal standards.

Clark County Air Quality and Environmental Management officials today issued an air quality advisory, warning people with respiratory problems, especially children and the elderly, to limit outdoor activities.

Moderate ozone readings were recorded at five of 13 air pollution monitoring sites during an eight-hour period. Ozone problems occur when sunlight, high temperatures and stagnant air conditions trigger pollutants.

High dust readings before dawn today were recorded at monitoring stations at city center, Craig Road, East Charleston Boulevard and J.D. Smith Junior School on East Tonopah Avenue in North Las Vegas, but had declined after sunrise, said David Dickens, monitoring technician for Air Quality Management.

However, because pollution is measured in a 24-hour cycle, Southern Nevada may wind up not exceeding pollution levels for the day for either dust or ozone, he said.

"We think that it (ozone) is the result of transport from California and not generated by us," Dickens said. "With high winds like we've been having, such readings are not affected by the ozone we generate. It would blow away."

The Environmental Protection Agency still considers it Las Vegas' problem, he said.

Dickens said the concern is that Southern Nevada is experiencing ozone problems earlier in the year than usual. To date, the two unhealthy days for zone this year were on May 11 and Sunday, compared with the first two ozone-caused unhealthy days last year on May 26 and 27.