Opinion ID: 392800
Heading Depth: 1
Heading Rank: 4

Heading: the hydrocarbon test procedure

Text: 124 One small issue remains. At the same time that the EPA issued its particulate regulations, it also modified the test procedures for measuring hydrocarbon emissions from diesel vehicles. See 45 Fed.Reg. 14,496, 14,500 (1980). GM challenges that method. 125 Application of heat during the hydrocarbon measuring process results in the release in free, gaseous form of hydrocarbons that would at lower temperatures have remained adsorbed to the surface of particulates. The EPA's hydrocarbon test procedure counts these as hydrocarbons; the particulate test counts them as particulates. GM objects to measurement of these emissions as hydrocarbons, asserting that they do not contribute to air pollution problems, and that GM is a victim of double counting. 126 The EPA rejected GM's complaints on several grounds; we agree with all of these. First, the statute requires the agency to measure total hydrocarbon emissions, regardless of the reactive potential of individual hydrocarbon compounds. 45 Fed.Reg. 48,133, 48,140 (1980). This court has already upheld the EPA's attention to total hydrocarbon emissions as a valid administrative interpretation of the Act, even in the context of admittedly nonreactive hydrocarbons. Ford Motor Co. v. EPA, 604 F.2d 685 (D.C.Cir.1979). Second, the EPA found GM's test data exonerating adsorbed hydrocarbons unconvincing, because the tests performed were unrealistic in simulating atmospheric conditions. 45 Fed.Reg. 14,496, 14,505 (1980). The EPA thus regarded it as an open question whether particle-bound hydrocarbons contribute first to the particulate problem and then later to the hydrocarbon pollution problem as well. Analysis of Comments at 132, J.A. 454. 127 Finally, despite GM's characterization of the test as double counting, GM has not shown that it is prejudiced by inclusion of adsorbed hydrocarbons in the particulate measurements. Adsorbed hydrocarbons are included in determining compliance with the absolute statutory hydrocarbon emission standard, and so their measurement is significant. But the particulate standards are technology-based, and therefore are set at a level that already includes any inflation due to adsorbed hydrocarbons. 45 Fed.Reg. 48,133, 48,140 n.76 (1980). We do not see any fundamental unfairness for the vehicle manufacturers in this test procedure.