Residents of Charleston, West Virginia, where drinking water was contaminated with the unregulated industrial chemical MCHM following a storage tank rupture upstream of the city's intake, faced elevated health risks compared to neighboring communities that were not affected, according to a state investigation released in the years after the spill. The findings renewed longstanding questions about source-water protection and the federal government's approach to industrial chemicals that enter the drinking water supply before they are studied or regulated.
On January 9, 2014, a storage tank owned by Freedom Industries leaked approximately 10,000 gallons of crude MCHM -- a coal-processing agent -- into the Elk River just 1.5 miles upstream of West Virginia American Water's Kanawha Valley treatment facility, the primary water source for some 300,000 people in nine counties. Within hours, the company issued a "Do Not Use" order covering drinking, cooking, and bathing. For days, residents lined up at water distribution points while officials worked to determine what level of the chemical was safe -- a question that turned out to have no clear answer, because MCHM had never been subjected to the toxicological testing required for regulated contaminants.
The chemical "was everywhere," as workers near the site described it, carrying a faint licorice odor that residents reported smelling from their tap water even after the advisory was lifted. At the time, neither state regulators nor the federal Environmental Protection Agency had enforceable standards for MCHM in drinking water. Called a "frother" because it reduces the surface tension of the wash water used in coal processing, the compound had been used in facilities throughout Appalachia for decades, stored in tanks that were largely exempt from routine inspection by state or federal authorities.
MCHM, which is classified by the EPA's Toxic Substances Control Act inventory as an existing chemical, had been in commercial use since the 1970s. At the time of the Elk River spill, the compound had not been evaluated for chronic health effects in humans, and the only toxicological data available were limited animal studies commissioned by the manufacturer. Federal health officials from the Agency for Toxic Substances and Disease Registry eventually set a provisional screening level of 1 part per million, but acknowledged the figure was based on sparse data and did not account for sensitive populations, including pregnant women or people with compromised immune systems.
New data that emerged in the months after the spill suggested that even the provisional threshold used to lift the Do Not Use order may not have reflected the evidence that very low concentrations of the chemical can cause irritation and other effects, according to toxicologists reviewing the available literature at the time. Researchers at the National Institute for Environmental Health Sciences noted that MCHM, like many industrial chemicals that have not gone through the standard SDWA review process, had simply never been nominated for the kind of systematic two-year study that would allow regulators to calculate what would constitute a health-protective level. "That's not the way things work," one federal toxicologist remarked. "You don't get a safety threshold for free -- someone has to do the study."
The Elk River spill exposed a structural gap in how the Safe Drinking Water Act handles unregulated chemicals. Under the law, the EPA is required to publish a Contaminant Candidate List and periodically evaluate whether substances used in industrial processes near water intakes should be regulated. But the agency places the greatest priority on chemicals that are toxic, persist in the environment, and accumulate in people's bodies. MCHM, an organic compound that breaks down relatively quickly, was not considered a strong candidate for regulatory priority -- even as thousands of gallons of it sat in aging tanks just upstream of a major drinking water intake.
More than a decade later, the water system serving ZIP code 25301 in Charleston carries 1 health-based violation in the five-year EPA record, along with 52 total violations, according to ZipCheckup's home safety profile for 25301, which aggregates EPA SDWIS data alongside lead, radon, and flood risk figures for each ZIP code nationally. The water system, Wvawc-Kanawha Valley District, serves approximately 209,283 people from surface water sources -- the same Elk River watershed that brought the 2014 crisis into national view. The current lead reading of 0.001 mg/L is well below the EPA action level, and the overall home safety score has improved to 94 out of 100. But the compliance risk forecast in EPA enforcement records shows a 95 percent probability of a new violation within two years, based on a historical rate of 6.22 violation events per year.
The 2014 spill drew national attention to a regulatory category that has received far less scrutiny than the contaminants typically covered by SDWA -- industrial chemicals stored near surface-water intakes that are not listed on any monitoring schedule. In the aftermath, Congress passed the Protecting Our Infrastructure of Pipelines and Enhancing Safety Act, and West Virginia updated its aboveground storage tank law. But the broader question of how many other communities draw their water from rivers and reservoirs located near unmonitored chemical storage facilities has never been fully answered. For Charleston, the Elk River incident remains the most direct expression of what source-water vulnerability looks like when it becomes, briefly and terrifyingly, impossible to ignore.