Spills and Releases

COMMON TERMS USED WHEN THE COMMUNITY IS NOTIFIED OF A SPILL OR RELEASE

Industry Terminology

In Ontario, spills of any quantity need to be reported to the Ministry. Specific regulations and industry standards also have public reporting requirements.  For example, the industry standards for petroleum refineries and chemical plants require the measurement of benzene and 1,3 butadiene along the fence-line of facilities registered to the standard every two weeks where these measurements need to be reported publicly to their web-site within 60 days of the sample being taken.

Using notifications collected from the last year, we've broken down the commonly used and often inaccessible language the community is left with during and after a incident.  

Process Upset: Otherwise known as Operational disruption or failure disturbs the normal process and could lead to increased discharges to the environment (air, water or land). Process upsets can be caused by inefficiencies in the process design, organization and operating procedures , equipment defects or human factors (failures caused by the personnel servicing the process). This phrase does not give specific detail about which of the many processes at the refinery went wrong. It also does not identify the error or problem that occurred.  

A better description would identify what process went wrong, why, for how long, what chemicals were discharged to the environment, and what are the risks to the community? 

Hydrocarbons: The term hydrocarbons is used to describe a broad class of chemicals that is entirely composed of hydrogen and carbon atoms.  There are thousands of hydrocarbons, and they can take the form of gases, liquids, or solids. Methane, Ethane, Propane, Butane, Benzene, Toluene, Xylene, and Naphthalene are all examples of hydrocarbons, and there are many more. Each hydrocarbon has its own level and kind of toxicity. The word hydrocarbons tells us very little about the pollutant and its possible harms. 

Acid Gas Flaring: This term refers to the combustion, in a Flare, of acid gases which contain a highly concentrated waste stream of hydrogen sulphide gas (up to 90 percent pure).  Acid gas flaring occurs with the Sulphur Recovery Unit (SRU) fails and gases have to be diverted to the flare.  Use of a flare for combusting acid gas instead of processing it in the SRU produces very large uncontrolled releases of sulphur dioxide (SO2). Acid gas flaring is designed to prevent the direct release of the very toxic and odorous hydrogen sulphide during malfunctions at the SRU.  However, one day of acid gas flaring can easily release more SO2 than is released in a single year. 

Unplanned Startup/Shutdown: Shutdowns and startups at a facility can lead to increased risk for environmental releases and problems.  This description of an event is vague because it does not specify what exact process in the plant is being shut down/started up, why the shutdown/start up is occurring, and what precise chemical releases are involved. Unplanned events are typically associated with process upsets.  

Questions remain about the cause of the startup/shutdown, what precise processes were affected, what chemicals are being released, what are the risks, how long will the chemicals be released, and what are the risks to the community?

Planned Plant Startup/Shutdown: Shutdowns and startups at a facility can lead to increased risks from chemical releases. When an event is described as a “planned shutdown” or “planned start up” it implies that it is not an event related to a problem or process upset.  However, it can also be the result of an earlier process upset and equipment being put back on line.  This description of an event is vague because it does not specify what exact process in the plant is being started up or shut down, and why.  

Questions remain about the cause of the planned startup/shutdown, how long it was planned for, and what precise processes, chemicals, risks, and releases are involved. 

Unit: This term is not helpful as it does not name what specific process of the plant is involved.  Unit is a vague term that could refer to any part of the plant. A better description would name the precise unit and process, as well as chemicals and possible environmental releases involved. 

Elevated flaring: The term elevated flares does not provide specific information about the kind of gas being combusted, and the specific pollutants it generates. The term elevated flaring does not provide details about the duration or size of the flare. We do not know what the threshold for how intense a flare has to be before it is reported to the public. Notices about flaring also do not describe why the elevated flaring is occurring.  

Did the plant make a decision to increase a flare for safety purposes? Was there a problem, if so what was it?  Was a decision involved to save wear on the plant by flaring, and hence put cost-saving ahead of pollution risks to the community?  

In this context, the adjective ”elevated” implies more than normal. Flaring is a safety mechanism at petroleum refineries, steel mills and chemical plants and cannot be totally eliminated.  However, it should be minimized; particularly for acid gas flaring since this type of flaring emits toxic sulphur dioxide which can pose a significant health risk to surrounding communities (i.e., any acid gas flaring that results in maximum 10 minute average point of impingement concentration above 30 parts per billion; equivalent to about 75 micrograms per cubic metre at 20 oC).  

Disruption: This is a general term that does not describe the nature of the problem, the part of the plant affected, the chemicals involved, nor the environmental releases and risks to the community.  A better description would name the unit, the cause of the problem, the chemicals involved, and the kind of releases, and the risks to the community. It would also provide information about timing.

Upset: This is a general term that does not describe the nature of the problem, the part of the plant affected, the chemicals involved, nor the environmental releases and risks to the community.  A better description would name the unit, the cause of the problem, the chemicals, and the kind of releases, and the risks.  It would also provide information how long it will take to fix the problem and how often the problem has occurred previously.  

Release: This is a general term that can be used to describe emissions that happen regularly at a plant, accidents, spills, leaks, process upsets or acute pollution events. The term release tells us very little about the specific chemicals involved, risks to the community, the duration of the event, or the cause of the release occurring.  

We also do not know at what threshold a release is reported to the public. How severe does a release have to be for a notification to occur?

Leak: A leak at a chemical plant or refinery refers to the discharge of gases from faulty process components such as valves, pump or compressor seals, and welded or bolted connections. These leaks from faulty process components may also result in liquid droplet discharges.