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How Safety Leaders Should Respond to an Environmental Incident or Spill

Apr 23, 2024
Two workers holding documents during an operational meeting

Organizations are expecting safety leaders to contribute more to their environmental protection and sustainability programs. As these responsibilities expand, safety leaders should be prepared to investigate environmental incidents or spills more effectively. 

“We have to know what happened before we can know why it happened,” says Tim Diggs, executive advisor for TapRooT® Root Cause Analysis implementation and development with System Improvements Inc. “This is your opportunity to see where the gaps in the system are and to improve your processes.”

Diggs recently offered guidance to our Environmental Practice Specialty on how safety leaders should respond to an environmental incident or spill. He says these incidents occur whenever contact occurs between a hazard — typically a dangerous source of energy — and people, wildlife and/or the environment. Such incidents are often due to a barrier, containment or safeguard failure, but that’s just the beginning of the investigation.

Step 1: Start Your Investigation With the Goal of Prevention, Not Punishment

When environmental incidents occur, the public wants to know who is responsible and how they will be punished, but safety leaders need to know how to prevent the incident from ever happening again, Diggs says.

For example, Company A uses a flexible hose to supply cool water to a water treatment unit. The hose ruptures, causing hot, low-PH water to release into the water outside the facility, causing a fish die-off and creating the potential for a $100,000 EPA fine, Diggs says.

It was easy for investigators to find someone to blame. In this case, the operator monitoring the water treatment unit fell asleep during his 12-hour overnight shift.

This is where a blame-oriented investigation would stop, but many causes contributed to this incident. That’s why safety leaders must dig deeper to uncover them, Diggs says.

Step 2: Gather the Right Kind of Evidence

To conduct a proper investigation, begin by gathering these four types of evidence:

  • Interviews
  • Physical evidence from the scene
  • Paper/digital records
  • Video or audio recordings

While interviews with employees and witnesses are key, they can’t be your sole sources of information. Witnesses may miss details or make assumptions, and you may not get a complete understanding of the entire incident or identify discrepancies without other forms of evidence, Diggs says.

Step 2: Perfect the Art of Interviews 

Interviewing is a somewhat lost art, Diggs says, so be prepared and hone your skills. Start by identifying who you want to interview:

  • First speak with those directly involved as quickly as possible.
  • Then move to those who were in the area at the time of the incident.
  • Next talk to outside experts who can help you understand the processes or equipment involved in the incident.
  • Finally, interview those with influence on the incident such as managers or regulators.

Diggs says following these tips can make your interviews more productive:

  • Avoid taking a blame-oriented stance and attempt to build rapport with your interviewee. Ask “how” and “what” questions instead of “why” questions.
  • Ask the subject to explain what happened from start to finish in their own words.
  • Prompt the interviewee to provide as much detail as possible.
  • Don’t interrupt. Interruptions by the interviewer can be leading and distracting, causing the subject to forget or omit information.
  • Allow silence. When someone is relaying a story, they may stop to process information — it doesn’t mean they’re done talking.
  • Ask clarifying questions to stimulate their memory.

In Diggs’ example, evidence gathering and interviews revealed several issues that led to the spill. First, the hose had never been inspected or the subject of preventive maintenance. The operator was on his fifth week of rotational shift work, which has documented negative sleep and health effects. The operator was also wearing double hearing protection due to the noise created by a nearby diesel generator, so he couldn’t hear the audible alarm. In addition, the automatic shut-off that would have prevented the incident had been disabled because it was sounding false alarms.

Step 3: Conduct a Thorough Root-Cause Analysis

While the investigation will provide information about why the incident occurred, you still must go another level deeper to understand the true causes.

“If we stop here, we are stuck on a surface-level investigation,” Diggs says. “These aren’t your causes. These are the mistakes that were made. We must understand how the system fails to understand how to fix it.”

Use root-cause analysis to uncover system failures such as procedures, equipment, tools, supervisory techniques, human factors design, communication, policies/rules, resources and training issues.

While it’s tempting to look for one primary root cause, you will likely find many causes to further investigate, Diggs says. If more than one barrier, container or safeguard was in place to prevent the incident, you will find more than one root cause. In Diggs’ example, safeguards included the operator, alarm and automatic shut-off.

Step 4: Take Corrective Actions

The root-cause analysis will help identify corrective actions that will prevent the incident from happening again.

Three common corrective actions are discipline, training and procedures, but Diggs says good safety leaders must think beyond them.

He relies on the safeguard hierarchy, similar to the hierarchy of controls, to determine corrective actions for addressing environmental incidents or spills. The top items in this safeguard hierarchy are the most effective and the bottom are least effective:

  • Remove or reduce the hazard
  • Remove the target
  • Guard the target
  • Improve human performance through:

    • Sound human factors design
    • Rules, procedures and signs
    • Training and supervision

Safety leaders should evaluate corrective actions not only based on their position in the hierarchy, but also the risk involved. If the risk is lower, a lower-ranking solution may be more appropriate, Diggs says.

In his example, recommended solutions included:

  • Replacing the broken hose and implementing a preventive maintenance and inspection program for the new hose
  • Moving the diesel generator so double hearing protection isn’t required
  • Repairing the automatic shut-off and posting information on how to troubleshoot or service it if false alarms occur
  • Updating operator scheduling to avoid irregular shift work
  • Installing a control on the operator’s panel that requires periodic operation to ensure the operator is awake

“Those are all better fixes than just firing that operator because he was sleeping and putting another operator into that same situation,” Diggs says.


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Charlie Byrd
Are there any templates that guide a safety risk control specialist during initial response to water intrusions or air quality concerns? 


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