It seems like a fairly straightforward idea to clean up the air: Cut down on commuters' auto mileage and you will reduce the exhaust pollution that their autos spew into the environment.
As ever, the devil is in the details.
Maryland found that out after several rounds of modifications and revisions of its commuter-trip-reduction plan for employers in the seven-county greater Baltimore area, including Harford.
The federal Environmental Protection Agency, which gets the Baltimore smog-reduction scheme from Maryland this month, also learned the lesson and took a series of backward steps from the original edicts for the nine worst smog areas in the United States.
Under the 1990 Clean Air Act, these auto-polluted airsheds had to reduce by 25 percent the number of single-rider motor vehicle trips by working commuters.
Employers of at least 100 workers at a single site were made responsible for the effort, subject to stiff fines for failure to comply. In the Baltimore area, about 2,000 employers are affected, 80 of them in Harford County.
States that failed to implement and enforce these commuter-trip-reduction plans were threatened with sanctions, such as loss of federal highway funds and restrictions on future industrial development (as it affects air quality).
The basic approach is to calculate how many employees arrive alone at work in a private car and then persuade a certain number of those commuters to switch to mass transit, walking, car pools or alternate work schedules.
The plans for each work site are due in November 1995, although the commuter-restrictions program would go into effect from April to September -- the hot, sunny months when the level of ozone formation from auto exhausts is the greatest.
Employers complain that the program requires a lot of surveys, registrations and other paper work even before they address the basic goal of getting workers to change their driving habits. And the government told the employers they couldn't force employees to change, or to penalize them if they did not.
The result, say Baltimore businesses, is a cost of nearly $100 million a year for developing and maintaining acceptable commuter-trip-reduction plans, even if their employees were not convinced to abandon single-rider car commuting.
In Harford County, the plan could affect about 23,000 workers at local work sites (not all of them living in this county) and nearly 50,000 other Harford residents who commute to jobs in other counties. With well over half its work force employed outside the county, Harford would be significantly affected, despite a smaller number of large county-based employers.
The largest employer and work site in the county to come under the plan is Aberdeen Proving Ground. Government employers as well as private businesses are covered.
The net sum of all this effort is a program that might reduce ozone, or dirty air, in the summer months in certain areas by a maximum of 1 percent, perhaps less. EPA Administrator Carol Browner has admitted that the commuter-trip programs, required Congress, will have minimal impact on the overall level of air pollution.
That's before you even consider the "good faith" excuse. EPA says it will not penalize states that make a good-faith effort toward achievement of the trip-reduction goals, even if they are not reached. And EPA told the states that it will not penalize employers that make a good faith effort toward their goals, even if they don't reduce commuter trips by 25 percent.
That may seem like a poor return on society's investment in this seemingly simple program. Especially since only nine smog zones are under trip-reduction orders; Baltimore has to comply, the Washington area does not.
But it underscores the disturbing message that most future gains in clean air (or prevention of further air quality degradation) will be marginal and ever more costly.
Keeping smog even at existing levels requires increasing government enforcement. More cars and more total miles driven each year means more total air pollution, even with the improved emissions-control technology on new autos.
We will continue to pay more for this auto hardware to reduce exhaust pollution, for cleaner-burning fuels, for tougher emissions inspections and costlier repairs to meet higher standards. Emission-based auto registration fees and steep gasoline taxes may be the next step.
So commuter-trip-reduction programs are just one more costly annoyance in the uncomfortable effort to control auto pollution and clean up the air.
There's certainly no reason why employers can't encourage, and facilitate, ride-sharing among workers. Or to structure work schedules to reduce rush-hour commuting, allowing some employees to work at home. Worksite shuttle van service could be subsidized as a commuter option.
The Harford County school system began testing one plan this summer, switching the facilities maintenance staff to four-day workweeks. The schedule cuts commuter traffic at the Hickory office by 20 percent, officials say.
That's the kind of workplace adjustment that will become more common as we deal with the ominous consequences of more autos, more people and more smog.
Mike Burns is The Baltimore Sun's editorial writer in Harford County.