In the wake of a devastating train derailment that resulted in hazardous oil products spilling into Montana’s Yellowstone River due to a bridge collapse, the aftermath remains far from resolved. Even though cleanup operations have come to a halt, the river continues to bear the burden of petroleum asphalt contamination, raising concerns about environmental and health impacts.
The incident, which occurred two months ago, saw thick layers of tarry petroleum asphalt covering sections of sandbars. Rocks, bushes, and even chunks of yellow sulfur – a component of crude oil – now dot the river’s shoreline. In the middle of the river, a twisted mass of steel protrudes from the water, a reminder of the ruptured railroad tank car that caused the catastrophe.
Montana Rail Link, working in conjunction with federal and state authorities, recently scaled back cleanup efforts. They cited declining river levels that have exposed more pollution and impeded the safe operation of cleanup crews’ power boats. This cessation comes despite the fact that nearly half of the spilled 48,000 gallons of molten petroleum asphalt remains unrecovered. Data provided to The Associated Press reveals that around 450 sites contain asphalt in quantities deemed too insignificant or challenging for efficient removal.
The contamination stretches over a significant 125-mile (200-kilometer) span along the river, an area cherished by anglers, recreation enthusiasts, and farmers who rely on its waters for irrigation. Fortunately, Yellowstone National Park, located upstream, was spared from the disaster’s effects.
An on-the-ground assessment this week downstream of the repaired bridge underscored the scale of the remaining pollution. Islands in the river were marred by patches of asphalt clinging to vegetation and rocks, as well as thick tar mats oozing across sandbars, transformed into a viscous liquid by summer temperatures.
Wendy Weaver, Executive Director of Montana Freshwater Partners, a water protection nonprofit, stressed the necessity for a more comprehensive cleanup effort. Reports from over 40 sites that cleanup teams had already passed through have indicated the presence of tar balls and asphalt, suggesting the need for a second phase of cleanup.
Moreover, concerns have arisen regarding elevated levels of polycyclic aromatic hydrocarbons (PAHs), a toxic oil component, detected in mountain whitefish downstream from the spill site. An advisory has been issued against consuming fish caught within a 41-mile (66-kilometer) stretch of the Yellowstone. Although the link between the contamination and the derailment hasn’t been definitively established, the spilled asphalt did contain PAHs.
The impact of the spill on various fish species is still being investigated. Downstream drinking water and irrigation intakes were temporarily shut down after the accident but have since resumed operations without reported issues.
Asphalt, while less volatile than gasoline or diesel, releases toxic chemicals into the environment and poses a prolonged threat. Unlike its applications in road construction or roofing, asphalt in water doesn’t readily solidify, which can pose challenges. If ingested, it remains indigestible within most living organisms, potentially causing long-term harm.
Initially, federal and state officials warned against an overly aggressive cleanup approach, emphasizing the difficulty of recovering most of the spill without exacerbating environmental damage. In their efforts, cleanup teams gathered asphalt at 377 sites, along with more than 20 tons of debris that had adhered to the asphalt as it began to harden.
Montana Rail Link’s spokesperson, Andy Garland, assured that the company remained committed to addressing the spill’s consequences. They’ve decided, in collaboration with state and federal authorities, to adopt a different strategy and maintain a local task force to respond to asphalt reports.
To merit removal, the criteria include asphalt coverage greater than 20 inches (50 centimeters) wide in pebbles or rocks, or over 6 inches (15 centimeters) in sand.
Initial projections anticipated continued cleanup activities via both boats and land, extending into the fall. However, with receding water levels hindering progress, officials soon decided to scale back cleanup efforts. The threshold for this decision was three or fewer sites with extensive contamination within a 10-mile (16-kilometer) river stretch. This benchmark was met around 136 miles (219 kilometers) downstream from the bridge collapse.
Six tank cars filled with asphalt and three with molten sulfur entered the river during the derailment. The exact amount of released sulfur, also a petroleum product, and the quantity recovered have not been disclosed.
While sulfur can emit hazardous vapors at high temperatures, it becomes inert once cooled and solidified. This sets it apart from the lingering threat posed by asphalt.
This recent derailment marked the third significant petroleum spill into the Yellowstone River, following ruptures in crude oil pipelines beneath the river in 2011 and 2015. Only a fraction of the spilled oil from those incidents was recovered.
The cause of the bridge collapse is still under investigation, occurring during heavy rainfall and swollen river conditions due to melting mountain snow.
Montana Governor Greg Gianforte’s priority is safeguarding public health and the river’s well-being. A follow-up search for remaining asphalt is planned for next year, as shifting sandbars may expose further contamination. Concerns exist that the spring snowmelt could either wash the remaining asphalt downstream or bury it, raising worries about long-term consequences.