1. What Is A Chemical Incident?

The rise to prominence of the chemical industry over the past century and current use of innumerable chemicals in everyday life have increased the risk of exposure to or contamination by a host of substances that can threaten human, animal and/ or environmental health. Exposures may result from industrial or transportation accidents, from unintended contamination of products or from deliberate chemical releases. The recent use of chemical agents in warfare and in assassinations highlights how preparedness activities must accommodate both intentional and accidental chemical incidents. Whether a chemical incident is accidental or intentional, planning is necessary to mitigate all public and environmental health emergencies.

A chemical incident includes a wide scope of events and refers to the release, or potential release, of a chemical substance

1. that harms people, animals and/or the environment, regardless of accidental or deliberate cause, and/or
2. for which response needs have the potential to overwhelm state and local resources (both governmental and private sector), and/or
3. for which the Environmental Protection Agency (EPA) and/or the United States Coast Guard (USCG), co-Chairs of the National Response Team (NRT) for Oil and Chemical Spills under the National Oil and Hazardous Substances Pollution Contingency Plan (NCP),¹ deems that support is or will be required.

Note that response activities may be authorized in response to threatened discharges of hazardous substances that have not yet occurred, and that many chemical incidents are small in scope and scale do not require NCP-directed response activities. Further, if the substance released does not qualify as a hazardous waste, the incident may require federal response support under authorities other than the NCP; the NCP also does not cover releases into drinking water supplies due to normal deterioration of the water system.

In a chemical incident, harm to people, animals and/or the environment can result from chemical “exposures” and/or chemical “contamination.” Chemical exposure occurs when a chemical substance is absorbed into the body, while for humans (and animals), contamination means having a substance on one's clothing or body. For humans and animals, chemical substances are potentially hazardous by ingestion, inhalation and/or dermal contact. Thus, dangerous chemical exposure or contamination can come from food, water, air, or contaminated surfaces, and the spread of chemicals in the environment (such as through air and/or water movement) increases the risk of human and animal contamination and exposure.

The actions that must be taken by first responders to initiate incident response depend upon whether a chemical release has caused environmental, human, and/or animal exposures, contamination, or both.

Possible chemical incidents range considerably in their scale and their potential harm to public health and the environment. Some types of events happen frequently (mishaps during the transportation of chemicals) whereas others have happened rarely (deliberate chemical attacks). Preparedness activities should consider all of these factors when formulating plans and making decisions because the complexity of responses required will also vary with scale and the nature of the substance released. For example, a large-scale terrorist attack with a persistent chemical might result in a number of injuries from exposure and require decontamination operations, while a small-scale accidental chemical release of a chemical vapor may involve exposures but not contamination and therefore may require a far less complex response. In addition, the release of pollutants or contaminants that may reasonably be anticipated to cause harmful health effects upon exposure will require more capability and deliberate planning during the response.

There are several escalating layers of systems for the federal response to chemical incidents, allowing for appropriately-scaled responses to incidents that range from the less serious to those that may have catastrophic impacts. In the case of smaller incidents, the state, local, tribal and territorial (SLTT) governments, and/or the Responsible Party (RP) are often able to effectively address the response on their own. As incidents become larger and the responses more complex, the NCP may be activated, requiring a Federal On-Scene Coordinator (FOSC) from the EPA or USCG. In response to the most serious incidents, for example those cases involving a Presidential Disaster Declaration under the Stafford Act, the Federal Emergency Management Agency (FEMA) provides enhanced resource coordination under the National Response Framework² in support of FOSC authorities. (See the Federal Preparedness, Response, and Recovery section of this document for more information.) Historically, very few high-consequence chemical incidents have involved a Stafford Act declaration – such as the 1962 Louisiana and Mississippi chlorine barge accident and the evacuation of the New York Love Canal Chemical site in 1978. More recently, a 2014 West Virginia chemical spill (described below) and the 2016 Flint, Michigan water contamination events have been declared emergencies under the Stafford Act.

Even emergencies that do not rise to the level requiring a Stafford Act declaration may tax local abilities to respond and recover. This document will provide key insights necessary to inform a successful response. To set the stage for these discussions of key response and recovery activities, several chemical incidents are discussed briefly here. Events illustrative of three categories are presented: industrial accidents, including events occurring in the chemical supply and agricultural industries; transportation accidents, including events related to the movement of large quantities of chemicals; and deliberate events, in which chemicals were employed with the intent to cause harm.

1. National Oil and Hazardous Substances Pollution Contingency Plan, 40 CFR. § 300. (2011).

2. Federal Emergency Management Agency. (2019, October). National Response Framework. 4th edition.