By Emily Arthun, CEO, American Coal Council
For years, coal trains moving through West Coast cities have been portrayed as a serious public health threat rather than a routine part of the nation’s supply chain. Uncovered coal cars, in particular, have been blamed for worsening air quality in urban neighborhoods already facing significant environmental challenges. These claims have been repeated so often that many have come to accept them as settled fact — despite the lack of long‑term, real‑world data to support them.
That has now changed.
A detailed air‑monitoring report prepared during the redevelopment of the Oakland Army Base provides one of the most thorough examinations of this issue to date. Its conclusion is clear: coal trains passing through West Oakland did not increase levels of fine airborne particles, commonly known as PM2.5. This finding is based not on models or assumptions, but on years of direct measurement under everyday operating conditions.
The report states plainly that rail cars carrying uncovered coal around the Oakland Army Base “did not result in a measurable increase in regional PM2.5 levels” and “did not significantly contribute to regional air quality impacts in the West Oakland community.” These are strong conclusions, made cautiously and supported by nearly eight years of continuous monitoring.
The air‑monitoring program ran from late 2013 through early 2021. Three permanent monitors, owned by the City of Oakland, were installed to reflect typical conditions in West Oakland. One monitor was placed generally upwind of rail activity, while two were located downwind in residential neighborhoods, including near an elementary school.
These sites measured air quality every hour, across seasons, weather patterns, and varying operating conditions. The monitors were regularly calibrated, and the data were collected and reviewed by the Bay Area Air Quality Management District.
To determine whether coal trains had any measurable effect, rail traffic records were used to identify days when uncovered coal cars passed through the area. In total, the study examined 115 days with coal train traffic, including days when trains carried more than 100 uncovered coal cars.
Air‑quality readings from those days were compared directly with readings from days when no coal trains passed through West Oakland.
The results were consistent across all three monitoring locations. Air‑quality measurements on days with coal trains closely matched measurements from days without coal trains. There was no correlation between the presence—or number—of coal cars and elevated PM2.5 levels.
Even on days with heavier coal traffic, particle concentrations remained below the federal 24‑hour health standard in nearly every case.
Only two days during the entire monitoring period exceeded that daily standard. In both instances, particle levels measured at the upwind monitor were similar to those recorded downwind, indicating a regional pollution event rather than a rail‑related source.
he report also notes that elevated particle levels occurred on the day before coal trains moved through the area, further undermining claims that coal cars caused the increase.
In simple terms, West Oakland’s air‑quality challenges were present before coal trains arrived — and persisted regardless of whether they passed through.
The study also examined soot concentrations, commonly used as an indicator of diesel pollution. These measurements followed a clear seasonal pattern, rising in colder months and falling in warmer ones.
This trend is consistent with regional pollution sources rather than activity associated with rail operations. Once again, coal trains did not register as a meaningful factor.
Taken together, the data lead to a straightforward conclusion: coal trains were not changing air quality in West Oakland.
This matters because coal trains have become a powerful symbol in environmental debates—not because they are a major pollution source, but because they are visible and politically easy to target. Visibility, however, is not the same as impact. The Oakland report reinforces a broader reality that often goes unspoken: cities themselves are the largest generators of air pollution.
Urban areas concentrate traffic, freight movement, ports, warehouses, construction activity, and energy demand in tight spaces. Traffic congestion alone produces enormous amounts of pollution each day. Add diesel trucks serving ports and distribution centers, ships at dock, construction equipment, aircraft overhead, and the energy required to power dense neighborhoods, and the scale becomes clear. Together, these sources far outweigh the impact of a train passing through once or twice a day.
West Oakland still faces serious environmental challenges, and the report does not deny that reality. What it does deny—clearly and convincingly—is the claim that uncovered coal trains are a meaningful cause of those challenges. That distinction matters for public policy.
Improving air quality requires focusing on the sources that actually drive pollution. Targeting coal trains when years of monitoring show they are not contributing to the problem diverts attention from actions that could make a real difference. It risks turning environmental policy into a symbolic exercise rather than a practical one.
Coal continues to play an important role in the economy, particularly in steelmaking and global energy supply. Moving coal safely and efficiently supports jobs, trade, and reliability—and the Oakland data demonstrate that this transportation can occur without degrading local air quality.
Public trust depends on honest, data‑driven decision‑making. After years of measurement and review, the evidence is firmly on the record: coal trains were not the source of West Oakland’s particle pollution. Facts, not fear, should guide the conversation.
By Emily Arthun, CEO, American Coal Council
