Nearly 9,000 Denver-area vehicles “disappeared” after failing their auto-emissions tests last year — at least 200 of which have been spotted out on the roads illegally, according to a new state review.
Although many of the polluting vehicles may wind up in scrap heaps, collect dust in garages or be sold outside the seven-county metro area, remote pollution-control monitors have identified at least 2 percent still being operated in the region.
While the problem is small, experts say that the dirtiest 10 percent of vehicles generate as much as 50 percent of the area’s “mobile-source” pollution, and scofflaws are drawing ever greater scrutiny as the metro area struggles to meet federal pollution standards.
Because the Denver region failed to meet federal clean-air ozone standards this past summer, the state is under orders from the U.S. Environmental Protection Agency to tighten its pollution controls.
“Knowing that we have air-quality issues you want to make sure that you get every ton of pollution you can out of the (testing) program,” said Garry Kaufman, manager of mobile-sources pollution control for the state health department.
It’s also a matter of fairness, he said, noting that the large majority of vehicle owners seek repairs after failing emissions tests.
About 6 percent of the 740,000 vehicles tested in the metro area last year failed the IM-240 test.
The test — which costs $25 — measures carbon monoxide, hydrocarbons and nitrogen oxides, which create ozone, emitted under driving conditions simulated by a treadmill device.
Motorists have 30 days to perform repairs and have their vehicles retested. They can obtain a waiver if after $715 spent on repairs their vehicles still don’t pass the second test.
Vehicles generally are tested every two years as a condition of license-plate renewal.
Many drive illegally
Nationally, between 10 percent and 15 percent of vehicles that fail initial emissions tests never show up for retesting, said Tom Wenzel, a scientist with the Lawrence Berkeley National Laboratory who specializes in auto emissions.
“They could be moved out of the area,” Wenzel said. “They could be moved out of the state. They could be stored in a garage. And then a certain fraction of those vehicles continue to be driven.”
A federal EPA study of inspection programs on the East Coast found that many motorists simply drive their vehicles without proper licensing.
In Maryland, 1,665 vehicles failed an initial test, never underwent re-testing, and then failed a subsequent test when brought in two years later as a condition of license-plate renewal.
Of the vehicles that “disappeared” in 2006 after failing emissions tests in Colorado, about 2,600 — 30 percent — have shown up for new tests this year through this August, the latest month for which figures are available.
Getting around the law
In some cases, owners will change the addresses on their registrations to second homes outside the metro area or will put the title in the name of a relative to avoid the emissions tests.
“It’s more than just the money,” Wenzel said. “People just don’t like the government intervening in their rights to drive.”
Few studies have attempted to measure the amount of pollution emitted by vehicles that have failed the tests but continue to operate on the roads, he said.
“In general, states feel: ‘It’s a problem, but it’s not so many vehicles for us to make a big effort to go after them,’ ” Wenzel said.
After the Denver region violated federal ozone standards this past summer, officials in Colorado are considering tightening emissions standards on all vehicles.
Starting in January, they will begin to require repairs from owners of dirty cars even if they have a valid test that is less than 2 years old.
The state is also considering tracking down the vehicles that have disappeared, in part to see if they are driven regularly in the metro area — and therefore subject to an emissions test, even if they are registered elsewhere.
“It’s really like finding a needle in a haystack,” Kaufman said. “We do feel strongly we want to catch as many of these as possible.”
Steve Lipsher: 970-513-9495 or slipsher@denverpost.com.
