Opinion ID: 519994
Heading Depth: 3
Heading Rank: 1

Heading: Analytical Variability

Text: 276 The analytical methods for measuring pollutants become unreliable at the low concentrations the EPA has established in the limitations. Two different laboratories, each using acceptable methods, may measure the pollutant in a given sample and reach different results, yet neither lab may be demonstrably wrong. This has been referred to above as analytical variability. Monsanto, Dupont, and CMA contend that the BAT limits cannot be achieved because analytical variability will in some instances inevitably result in a detection reading (or laboratory measurement) in excess of the limitations even though the true value of the sample is within the limits. 277 The EPA responds by asserting that analytical variability was adequately accounted for in its derivation of the BAT limitations. As previously discussed, the variability factors were derived from empirically-observed variations in measurements due either to analytical variability or to routine fluctuations in a plant's performance. To calculate the BAT limits, the EPA multiplied the long-term averages by the variability factor, and because it did so, the EPA asserts, its statistical model necessarily accounts for analytical variability. 278 The record shows, and the EPA concedes, that certain pollutants are subject to substantial analytical variability. In review proceedings, however, the burden is on the petitioner to show that the Administrator's determination was arbitrary, capricious, or an abuse of discretion. 211 The industrial petitioners have not shown that the variability factors the EPA assigned to the respective pollutants failed to account for analytical variability, and therefore the petitioners have failed to meet their burden.