WASHINGTON-Enhanced vehicle emissions inspection and maintenance-a cornerstone of the Clean Air Act amendments of 1990-has become embroiled in controversy. House Republicans, mindful of growing state discontent over strict Environmental Protection Agency enforcement of enhanced I/M, passed an amendment to a budget-cutting bill March 16 which forbids the EPA from forcing the states to accept it.
Shortly afterward, on March 23 and 24, the Oversight and Investigation Subcommittee of the House Commerce Committee held hearings on enhanced I/M, which revealed even more acrimony among the subcommittee's members than among the deeply divided witnesses who testified.
The EPA plan for enhanced I/M requires the use of a stringent new ``IM-240'' test which, the agency insists, is much more accurate than the old emissions test. It also strongly promotes the establishment of separate test-only facilities, replacing the decentralized, test-and-repair programs in most states.
Although the agency approved decentralized testing in some states, it gives decentralized testing centers only 50 percent of the credit for emissions reductions it postulates for test-only facilities. If a state fails to meet EPA emissions reduction goals, the agency is empowered to withhold the state's federal highway funds.
This harshness caused states to rebel against enhanced I/M, and the House to seek ways to forestall it. Rep. Tom DeLay, R-Texas, who sponsored the amendment to the budget bill, said 22 of the 28 states required to establish enhanced I/M, have suspended or postponed it.
The House Commerce Oversight hearings began with senior Democrats-including Reps. Ron Wyden of Oregon, Henry Waxman of California and John Dingell of Michigan-chiding the Republican leadership for not allowing testimony by six witnesses the Democrats had requested.
Two such excluded witnesses, Thomas C. Austin of Sierra Research Inc. and independent consultant Michael Walsh, were set to assert test-only facilities are far superior to test-and-repair. The witnesses who did appear mostly argued the opposite.
David Kittelson and Huel Sherrer of the University of Minnesota told the subcommittee that Minnesota's enhanced I/M program had not caused any measurable decrease in carbon monoxide levels. But after the hearing, Mr. Austin said the Minnesota study was flawed and didn't make a feasible case against test-only facilities.