Spill Response: Beyond the 'Worst Case Scenario'
Regulations clearly state that facilities must plan for the worst. Take time to also plan for the "more common."
- By Karen D. Hamel
- Jul 01, 2005
FORTUNATELY, it's not every day that a 10,000-gallon holding tank fails or a forklift harpoons a drum of solvent sitting next to a floor drain. But no matter what spills, facilities need to be prepared.
Governing agencies such as the Occupational Safety and Health Administration, the Environmental Protection Agency, and the U.S. Department of Transportation have created various regulations that spell out which plans need to be established, who needs to be prepared and trained, when agencies need to be notified of a release, etc. Some even require coordinators to evaluate facilities and processes for ways to prevent spills from occurring so the likelihood of needing to respond to a spill is minimized.
When creating spill response plans, some facility coordinators focus their efforts on the "worst case scenario" spill, possibly because it is mentioned most often. One theory supporting this is that if the facility is prepared for the worst, it can handle anything else. Unfortunately, if the "worst case scenario" is something like the rupture of a large storage tank outdoors, and the bulk of the response plan involves using backhoes to create earthen dikes; more common spills and the supplies and responses for them can be overlooked. Also commonly overlooked are "nuisance spills," such as when a main waterline to the locker room showers bursts in the middle of the night, flooding half of the facility by morning.
It's easy enough to walk through a facility and find the biggest container or tank on site, but it's just as important to locate all of the others, as well. Even if all liquids stored on site have containment or secondary containment, all pipes have reinforced connections, and there are no floor drains, these precautions could fail in a natural or manmade disaster.
Some plans require coordinators to mark the location of tanks and containers on a facility diagram or blueprint. While doing this, don't forget pipelines and floor drains. Determine where the pipes and drains lead. Do they go to or from a holding tank? Do they feed a process? Do they lead to an on-site treatment facility, a sanitary sewer, or a storm sewer? Where are the shutoffs?
Knowing this information is a critical element of spill response because if something enters a drain that leaves the facility, the spill may need to be reported to various agencies and response equipment may be needed downstream or at the nearest public water treatment facility. If a pipe, fitting, or valve leaks, knowing the first place that the flow can be stopped can mean the difference between a 10-gallon spill and a 100-gallon (or larger) spill.
After response plans are finalized, keep a copy of the blueprint or facility diagram with the plans and remember to check it when facility designs change or on a regular basis if nothing has "seemed to" change, to make sure that it remains accurate.
Even if regulations do not require a facility diagram or blueprint to be filed with plans, it can help both on site and in a large-scale incident with off-site responders when they plan a drill or actual response. Relying on the memories of employees during a stressful situation can cause confusion and delays. A clear, well-marked diagram allows the incident commander to show the response team members exactly where the spill is, how it is to be approached, where to find shutoffs and floor drains, etc.
Facility Design Considerations
Unless the facility has an on-site wastewater treatment plant and that plant is capable of and permitted to handle and treat spills, hosing anything that spills to the nearest floor drain is probably not an option in a spill situation. Although many on-site treatment facilities are designed to handle routine contaminants, such as small amounts of oil or coolant overspray, a major spill of these same items that they "normally handle" can foul their operations or cause them to exceed their effluent permit limits.
This means that before responders can start cleaning up a spill, they first need to contain or control the spill to prevent it from leaving the facility or from entering drains and other sensitive areas, such as offices, critical processing areas, computer rooms, and electrical components.
In a spill situation, floor design is one element that can be either a help or a hindrance. Knowing how, if, or where the floors are sloped; the permeability of floors; and the location of floor drains can help determine where a spill is likely to go, which helps responders know what they need to do when there is a spill. For example, if the floors are sloped to floor drains, simply closing or covering the drain might be enough to keep the spill contained.
In facilities with pieced wood block floors, a spill often goes straight down through the cracks in the floor to the earth below. This can be great if the spill is plain water because it won?t pool up, possibly causing damage to electronic components or spreading into neighboring work areas. It would not be good, however, if the spill is hazardous and now has a good chance of reaching an underground water table.
Facilities with floor drains tend to have slightly sloped floors that channel fluids toward the recessed drains. This feature is great for kitchens and food processing areas, for example, because it makes routine cleaning easier, but it also makes spills tougher to catch and contain.
Some facilities have level, epoxy-sealed floors. A sealed floor means a spill won't permeate through the floor, but it can also mean that the total area covered by a spill is larger because the spill moves laterally--not to one recessed area or down through the floor.
When planning, knowing the vapor density--whether vapors rise or sink--of the liquids stored on site may also be important because it can sometimes be another complicating factor. For example, a large spill that has reached doorways will likely negate the possibility of opening those doors to ventilate the building, which in turn might cause response efforts to be delayed until vapors dissipate or an alternative method is used to bring them to a safe level for responders to enter the scene.
After considering the liquids in the facility and marking the facility diagram with the locations of fluids, pipes, floor drains, and any sloping floor or other features, plan coordinators can use this as a guide for determining how a spill in each location of the facility will flow and the best way to stop a spill in that area from spreading. The smaller the area a spill covers, the smaller the area that needs to be cleaned up, the less downtime neighboring areas or processes will experience, and the smaller the chance that the spill is released to the environment.
In one area, such as a warehouse with a flat, sealed cement floor and no floor drains, a 30- to 60-gallon spill kit stocked with absorbent mats and socks might be a logical answer, if a spill in this area is likely to be from a 55-gallon drum or similar container. Putting the same 30- to 60-gallon spill kit in a processing area where the most likely spill is a 750-gallon coolant tank would probably not provide responders with the proper tools to handle this situation. Dikes and drain blocking devices might be a better option because they will help control the larger spill so it can be recovered with a vacuum. Considering each area individually helps ensure the appropriate response can be planned.
Will It Work?
Unfortunately, even with the locations of everything marked, response plans in place, and tools and equipment dedicated to response, it's very easy to underestimate the effects that a spill can have on a facility. Barring the "worst case' complications of the largest container or tank spilling, smaller containers, tanks, and pipelines can sometimes cause bigger headaches. A five-gallon container of hazardous waste that springs a leak on the loading dock and enters a storm drain is likely to cause more nightmares and bad press than 3,000 gallons of water from a cooling tower that is released but contained on site. Response to these two scenarios also will be quite different.
Drills are one way to know whether the plans will work. They also are a great way to get local fire companies and other outside emergency management resources involved so that if "the worst" ever does happen, both on-site and off-site responders will know how to work together during what is sure to be a stressful situation.
Also, outside resources may be able to assist in creating a mock spill. Many fire companies need to flush their tanker trucks routinely. Instead of your spending the money to fill a tank with water to create a mock spill, the fire company may be able to flush their tank at your facility to provide water for the simulation instead.
When creating plans, estimate the time it will take to get everything back to normal after a spill. If, for example, the facility uses specialty or custom valves, fittings, or parts, list the names and phone numbers of suppliers in response plans as well as the lead time for parts to arrive. If the lead time is long and downtime at the facility needs to be minimized, consider stocking essential parts so operations can be resumed more quickly.
During response drills, keep track of the time it takes to respond. Consider how other complicating factors such as darkness, rain, snow, or injuries will affect this time. By being able to estimate the costs of the downtime a spill causes, expenses for response materials that minimize this time can be more easily justified.
Regulations clearly state that facilities must plan for the worst. Taking the time to also plan for the "more common" will help to ensure the facility is truly prepared to handle all of its spill situations.
This article appears in the July 2005 issue of Occupational Health & Safety.
This article originally appeared in the July 2005 issue of Occupational Health & Safety.