What does the exhaust from your car have to do with your state's ability to build highways? Often a lot. In fact, if any state does not cooperate to the degree Congress expects in improving the nation's air quality, it can lose promised federal highway funds, grants to help clean up the air, and any Washington help in building sewage treatment plants. Also, the discretionary power to issue permits for new or revamped factories or power plants that might further pollute the air could be withdrawn.
''They're kind of nasty sanctions,'' concedes Gene Tierney of the Inspection and Maintenance Division of the US Environmental Protection Agency (EPA). ''And the thing that caps it all is that (factory) construction moratorium.''
Washington's fiscal threats are unpopular, but no one disputes their effectiveness.
Consider the case for auto emissions testing.
A few years back well over half the states, realizing they could not meet the uniform air quality standards set under the Clean Air Act by the 1982 deadline, requested a five-year extension. To get it, they had to pledge to set up auto emissions testing programs in large urban areas or face what Mr. Tierney describes as the ''four-pronged fork'' of federal sanctions. To date, 24 states and the District of Columbia are operating auto emissions programs.
''I think without a doubt the sanctions are responsible for the fact that we have these programs going,'' Tierney insists.
Still, the threat of a Washington funds cutoff doesn't always automatically make the difference. Testing auto exhausts is a politically controversial issue involving tough questions of whether the whole state or just urban motorists should pay for it and of whether or not car owners will put up with the added hassle.
Illinois is one of the states that sought an extension, but as yet it has no emissions program operating in either the Chicago area or East St. Louis, as required. The state environmental agency opposed exhaust testing as unnecessary, and legislators for a time tried to put tougher controls on industry pollution instead.
In the end, it took a compromise gift to rural legislators (exempting parts of otherwise urban counties), strong reminders by Gov. James R. Thompson of the dire consequences of the potential $100 million highway fund loss, pressure from neighboring Wisconsin Gov. Anthony Earl, who complained that Chicago's exhaust pollution wafted northward, and the last-minute celebrity arrival of EPA chief William Ruckleshaus to actually seal the deal.
Finally, on the last day of its session this summer, the Illinois legislature enacted the $30 million program. It will be supported by the state fuel tax.
''The thing that finally convinced the legislators,'' says Kevin Greene of Citizens for a Better Environment, ''was the sanctions. That did it.''
EPA Chicago regional office spokeswoman Virginia Donahue insists it was also her agency's threat of sanctions against Michigan in early June, followed by public hearings, which prodded the legislature there to take the required action this summer.
Ms. Donahue said during the hearings, which she sat in on, ''I was concerned with the very high level of concern about sanctions. There's a lot of money involved.''
Yet in a handful of cases the EPA has actually had to make good on its threats. It withheld funds for a time from California, Colorado, Pennsylvania, and parts of Kentucky and Tennesee.
Tierney says the abrupt halt of Interstate Highway 95 in Philadelphia is graphic evidence of the effect of the highways funds cutoff there. And he suggests that one of the reasons Nashville quickly moved into compliance after the EPA implemented sanctions against it last April was its desire to issue a permit (scotched by the sanctions) to a company planning to convert waste into electricity.
The EPA is now lifting those sanctions.
Some motorists dispute the relative effectiveness of regulating car exhausts in the war on pollution, saying they often see blacker smoke spewing from buses and factories. EPA spokesmen insist that the kind of emissions they are trying to curb are largely invisible. They say car emissions tests in urban areas can reduce carbon monoxide by one-third and hydrocarbons (which combine with sunlight to form ozone) by as much as one-fourth.
''It isn't going to turn the situation around, but it's part of the solution, '' says Mr. Greene of Citizens for a Better Environment. ''It's been a long process, but I think the law has worked. We're getting very close to meeting the standards.''