Attorneys for BNSF Railway, a Warren Buffett-owned company, are set to argue before jurors that the railroad should not be held liable for the lung cancer deaths of two former residents of Libby, Montana, one of the deadliest sites in the federal Superfund pollution program. The railroad's corporate predecessors claim they were unaware that the vermiculite they hauled from a nearby mine was contaminated with hazardous asbestos fibers. The case, the first of many lawsuits against the Texas-based railroad corporation, revolves around its past operations in Libby, where asbestos exposure has been linked to several hundred deaths and thousands of illnesses.

The trial has shed light on the role of W.R. Grace & Co., a chemical company that operated the vermiculite mine near Libby until 1990. The Maryland-based company has paid significant settlements to victims and faced criminal charges over the contamination. However, US District Court Judge Brian Morris has emphasized that Grace's liability is separate from that of BNSF, urging jurors to focus on the railroad's conduct.

Former railroad workers have testified that they were unaware of the risks of asbestos exposure, with some claiming that Grace employees concealed the health hazards. The families of the deceased plaintiffs argue that BNSF should have been aware of the dangers, pointing to warning labels on rail cars carrying vermiculite in the late 1970s. The Environmental Protection Agency declared a public health emergency in Libby in 2009, leading to a cleanup effort that has largely been funded by the public.

The trial has brought to light the devastating impact of asbestos exposure, with family members testifying about the rapid decline and death of their loved ones due to mesothelioma. The plaintiffs argue that BNSF should be held accountable for knowingly exposing people to asbestos at its railyard in Libby. The long-term effects of asbestos-related diseases mean that people previously exposed are likely to continue getting sick and dying for years to come, according to health officials.