Opinion ID: 326929
Heading Depth: 3
Heading Rank: 1

Heading: The Nature of the Discharge.

Text: 58 The comparability of the nature of Reserve's discharge to the nature of the discharge in known disease situations raises two principal questions. The first is whether the discharged fibers are identical or substantially identical to fibers known to cause disease; the second is whether the length of the fibers discharged is a relevant factor in assessing pathogenic effect. The district court found that Reserve's discharge includes known pathogenic fibers and that a lower risk to health could not be assigned to this discharge for reasons of fiber length. 59 On the first question the issue of the identity of the fibers the argument focuses on whether the ore mined by Reserve contains (and yields wastes during processing consistent with) amosite asbestos. The inquiry is critical because studies demonstrate that amosite, at least in occupational settings, may serve as a carcinogenic (cancer-producing) agent. A principal dispute concerns the precise composition of the mineral cummingtonite-grunerite found in Reserve's taconite ore: Reserve maintains that the cummingtonite-grunerite present in its Peter Mitchell Mine at Babbitt is not asbestiform and is not chemically consistent with amosite asbestos; plaintiffs argue that much of the cummingtonite-grunerite mined by Reserve is substantially identical to amosite asbestos. 60 As a general scientific proposition, it is clear that cummingtonite-grunerite embraces a range of chemistries, including the chemistry of amosite asbestos. The mineral also embraces a range of morphologies, from asbestiform, needle-like fibers to block-shaped, crystal aggregates. The crucial factual determination is, thus, whether the particular cummingtonite-grunerite mined by Reserve contains asbestiform fibers consistent with the properties of amosite asbestos. 61 The trial court heard extensive evidence as to the chemistry, crystallography and morphology of the cummingtonite-grunerite present in the mined ore. This evidence demonstrated that, at the level of the individual fiber, a portion of Reserve's cummingtonite-grunerite cannot be meaningfully distinguished from amosite asbestos. Reserve attempted to rebut this testimony by showing that the gross morphology of the two minerals differed and that characteristics of the two minerals varied when considered in crystal aggregations. Since, according to the opinions of some experts, the individual fiber probably serves as a carcinogenic agent, the district court viewed the variations in mineralogy as irrelevant and determined that Reserve discharges fibers substantially identical and in some instances identical to fibers of amosite asbestos. 62 The second question, that of fiber length, reflects a current dispute among scientists as to whether short fibers (i.e., fibers less than five microns in length) have any pathogenic effect. Most of the fibers detected in Reserve's discharges may be termed short. 28 The evidence adduced at trial included conflicting scientific studies and diverse opinions on this question. Several Reserve witnesses testified concerning animal studies which seem to demonstrate that short fibers are nontumorigenic. 29 Plaintiffs offered opposing evidence based on contrary studies. 30 Dr. Brown noted his general criticism of the studies on fiber size, stating that the researchers typically did not use electron microscopy to properly size the fibers, and thus it cannot be said that the animals are in fact being exposed to only short or only long fibers. (A.23:338-40.) 63 Presented with this conflicting and uncertain evidence from animal experimentation, and the fact that there are no human epidemiological studies bearing on the issue, the district court concluded that short fibers could not be assigned a lower relative risk than long fibers. 31 This conclusion comports with the uncertain state of scientific knowledge. Furthermore, Dr. Brown and the National Academy of Sciences reached the same conclusion. 32 64