Opinion ID: 2106246
Heading Depth: 1
Heading Rank: 5

Heading: Definition of Fibers

Text: The definition of fibers contained in the PCA permit was limited to chrysolite and amphibole mineral particles. All of the testimony before the Federal court and the state agencies related to those minerals. They were the only substances with carcinogenic properties considered for abatement. Although they are silicate minerals, there was no evidence that all other silicates had similarly dangerous propensities. Nevertheless the trial court adopted Reserve's proposal that all silicates be included in fiber counting. This, of course, would grossly distort the process of comparing fiber counts in a control city with fiber counts at Silver Bay since it would include a comparison of innocuous fibers with those which were carcinogenic. Reserve justifies this procedure on the ground that we have mandated a single standard for the entire taconite industry, and other industries may be generating silicate emissions which are potentially dangerous. What this argument overlooks is the fact that the Federal court has judicially determined that Reserve's operations occur in a unique area in the Mesabi range, 1 mile wide and 15 miles long. The taconite ore, which is there mined, contains the mineral cummingtonite grunerite which the Federal court said could not be meaningfully distinguished from amosite asbestos. [6] We hold that there was no justification for including all silicate mineral particles in fiber counting. For practical purposes that requirement would make it impossible to obtain reliable data with respect to demonstrably dangerous fibers at Silver Bay compared to a control city, wherever it is located.