CSB and Chemtool Fire – 6-21-21

Today the Chemical Safety Board announced that they were deploying two of its senior leadership members to Rockton, IL, the site of the June 14^th Chemtool Fire. A week ago the CSB decided not to send an active investigation team while the fire was still burning; their June 15^th statement said: “At this point assessments appear to indicate that the incident is a fire event and not a chemical process safety event.” The announced deployment will involve engagement “with Federal, State and local emergency responders, the Environmental Protection Agency (EPA) and others to determine the conditions and circumstances that led to the incident and to identify the cause or causes so similar incidents might be prevented.

The Incident

According to news reports (see here and here) early on Monday morning, June 14^th, a fire broke out at the Chemtool plant. On the first day, the decision was made to let the fire burn itself out, rather than pour water on the fire that could lead to toxic runoff into the nearby river. This decision was reversed the next day when an industrial fire fighting company was brought in to fight the fire with heavy foam. Early foam use reportedly included the use of a fluorinated foam that might contain the controversial Perfluorooctanoic acid (PFOA).

As of June 18^th, nearby residents that had been ordered to evacuate the immediate area around the plant were allowed to return home. While hotspot firefighting continues this marked the start of the cleanup process.

This is a fairly well documented incident. The local WREX web site contains a Chemtool fire coverage page that provides links to a largen number of news reports their team made over the five days of the incident. Similarly, the US EPA has a Chemtool Fire page that provides a daily summary of EPA actions with respect to the fire and environmental testing results.

Commentary

A look at the Google Satellite View of the facility shows a large industrial building with no obvious outside storage tanks. A twin rail line enters the facility for loading and unloading chemical railcars, so that extension of the building probably contains whatever tank farm the facility uses. There are no obvious diking or retention ponds outside of the building. This is why the firefighting crew on Tuesday had to resort to trenching between the facility and the river to contain any firefighting runoff.

Much is being made of a report on the sprinkler system installed at the facility. Sprinklers at a chemical facility are not nearly as effective at fire suppression as they are in residential or non-chemical industrial facilities. This is particularly true in facilities, like the Chemtool facility, that handle large quantities of liquid petrochemicals, as these are typically hydrophobic, so they do not mix well with water and are usually lighter than water. Applying water to burning petrochemicals has a tendency to move the flaming liquids about, spreading the fire. This is why the industrial fire fighting company brought in foam dispersal equipment, the foam stays on top of the flaming liquid and isolates the material from its oxygen supply.

I continue to be amazed by the lack of ponding around chemical facilities to catch firefighting runoff. In 26 years in the chemical process industry, I have been at two facilities that had off-site consequences from incidents involving firefighting water releases. One was when a deluge system released in a non-fire incident and the other was from a relatively short six-hour firefighting exercise. In both cases water left the facility grounds before anyone thought about diking or trenching.

In the first case large amounts of water with traces of relatively non-toxic chemicals resulted in a large fish-kill in a local creek with large fines. The second involved recovery of the runoff from miles of creek bed with hazardous material disposal costs larger the value of the destroyed facility. In both cases a dry pond with a closable weir would have prevented those costs from being accrued.