Ocean Lookout : Emissions: Monitoring station on Anacapa Island provides an early warning when unhealthy air is headed for the coast.

Anacapa Island seems a strange place for the West Coast’s only offshore air-quality monitoring station.

It’s 11 miles out to sea where the sky is clear and blue. There’s not a factory in sight. No pollution-producing cars roam its ragged hills. And, for that matter, not a single smoker can be found.

But officials are not worried about air pollution encroaching on the isolated island in the Channel Islands National Park. The island’s monitoring station gives the Ventura County Air Pollution Control District early warnings that unhealthy air is about to flow onto the mainland.

Using a collection of equipment that resembles stacked stereo components, officials can warn residents if polluted air from Los Angeles lurks at sea or if offshore oil platforms are producing too many pollutants.

“It’s a pre-warning device,” district meteorologist Kent Field said of the monitoring station. “If we get air pollution moving up or down the coast, we can tell using the data from Anacapa. . . . “

The station is vital when Santa Ana winds blowing from the east have pushed Ventura County pollutants out over the islands, where the emissions cook into a dangerous and dense mix of ozone pollution. Through a computer link to the mainland, the station can help warn Ventura County residents before normal winds from the west pick up and blow the polluted mass back ashore.

And when there is little pollution at hand, the station also provides valuable information on what Ventura County air would be like if there were no factories, power plants or cars to muck it up.

“It gives us a good idea of the effect that local emissions have on Ventura County air,” said William Mount, chief of planning for the district. “Out there, we don’t have the impacts of man’s daily activities.”

“We still get a mix of some air out there that blows from Ventura, Santa Barbara and Los Angeles, so it’s not really pristine,” said Richard Baldwin, the county’s top air pollution control official. “But it’s as close to pristine as you’re going to get in an urban environment.”

The tiny station, housed inside a 4-by-8-foot wooden shed tucked in the corner of a water tower building on the island’s east end, includes more than $100,000 worth of sophisticated pollution monitoring equipment. Nearby, another set of antennas and instruments propped atop a national park ranger’s house provide the district with information on wind and weather.

The Anacapa station costs an estimated $10,000 more a year to maintain than any one of the county’s six other air-pollution monitoring facilities. Rented helicopters used to transport technicians to the island every other week run up the tab, Baldwin said.

The district set up the station in 1981 when the oil industry was rapidly developing in the Santa Barbara Channel.

“There were a lot of concerns about the effects that oil development would have on our local air quality,” he said. “If it hadn’t been for offshore oil development, there wouldn’t be an offshore station.”

But placing the station 11 miles away from land has had its drawbacks.

Because the National Park Service limits the number of buildings allowed on the island, the station is squeezed into a corner of the existing water-tank storage building. The physical size of the station makes it possible for only two people at a time to work with the equipment.

“So going out there only once every two weeks, when we maintain the other stations twice a week, means the work is very intense,” said James McElroy, a district technician responsible for keeping the station in accurate working order.

McElroy, usually accompanied by another technician, takes readings from analyzers that show the levels of nitrogen oxide, sulfur dioxide and ozone in the air. They check the equipment for accuracy and repair any minor malfunctions on every visit.

McElroy said he loves the view going to and from the station, but there have been perils.

“There was a point when the rat population out here was so high that you didn’t want to set your lunch down because the rats would try to drag the sack off,” said Jim Balders, a district technician for 13 years. “And getting divebombed by sea gulls during rooking season is routine.”

During the spring and early summer, when sea gulls guard their nests and their young with territorial ferocity, the technicians have to watch their heads as well as their equipment.

When Field, wearing a white T-shirt, left the indoor monitoring station last June to check outdoor meteorological equipment, the gulls saw him as a threat to their nests.

“I guess they saw me as some giant sea gull,” he said. “I was their target. The other guys asked me to stand away from them while we waited for the helicopter because they kept coming after me.”