California's South Coast Air Quality Management District is expected next month to approve the deployment of cameras and sensors that will measure air pollution from 1 million vehicles in Los Angeles area counties, according to the Los Angeles Times on August 14. Studies have shown that scrapping high-polluting vehicles is among the most cost-effective ways of cleaning the air — far cheaper than additional controls on power plants and refineries. Yet politicians and state officials have failed for years to get the dirtiest cars off the streets, the article said. Current law does not yet allow the results from the devices to be used to issue citations, so the program will begin by offering incentives for "dirty" cars to be repaired or junked. Those who get a notice can receive up to $500 in repairs at select community colleges or $1000 for agreeing to junk the car. Air officials will not disclose the location of the sensors, other than saying most will be along freeway ramps and will be moved from place to place. A 2001 report by the National Academy of Sciences found smog-check programs generally failed to deliver the predicted pollution reductions, though it noted that they had made a positive impact. In California, an evaluation of the state program found that in 1999 it was achieving only 36 percent of the reductions state regulators had predicted.