The vast majority of Australian workplaces store and handle liquid substances - some of which have the potential to harm the environment and human health in the event of an uncontained spill.
This series of articles provides a complete guide to managing and responding to liquid spills in Australian workplaces
- Part One outlines the principles for preventing a liquid spill in the first place;
- Part Two outlines the principles of responding appropriately to a spill; and
- Part Three outlines the principles of managing waste associated with a spill.
Who Should Use This Guide to Spill Management?
This guide applies to any workplace that stores or handles liquid substances onsite. These can include corrosive, toxic or flammable liquids or even gases stored as a liquid under pressure, such as liquified petroleum gas (LPG)
Some of the workplace scenarios where the use of liquid substances are prevalent include:
- Fuel service stations storing petrol, diesel, oil and autogas
- Mechanics and other automotive businesses storing motor oils and fuel
- Council depots storing fuel, oil, paints and pesticides
- Farming businesses using and storing fuel and agricultural chemicals
- Manufacturers storing and handling industrial chemicals
- Food and beverage manufacturers producing milk products, fruit juices, etc.
- Offices storing heavy-duty cleaning products
- Fast food establishments using and storing cooking oils
- Research laboratories storing and handling hazardous chemicals
Personnel involved in workplace health and safety or site management will find this first article of the series useful for building an understanding of how to manage their site and liquid stores, prevent spills, implement monitoring procedures, and train personnel in liquid storage, and handling and spill management.
A spill kit is a vital component of a liquid spill response plan
What is Spill Prevention?
Preventing spills requires a combination of good site management, liquid storage management, active spill prevention, monitoring and maintenance, and staff training
What is Good Site Management?
The key components of good site management are:
- Risk management
- Site planning
- Site inspections, reporting and record keeping
- Site maintenance
What is Risk Management?
Assessing and managing the risks associated with storing and handling liquid substances - such as environmental pollution - can be effectively achieved using a risk assessment approach.
Risk itself is a combination of an event’s severity - its consequences - and its probability of occurring - the likelihood of it happening.
A professional risk assessment enables you to identify and quantify the risk of a damaging event occurring at your workplace. It also helps you direct your resources towards implementing preventative controls to mitigate those risks.
Assessing and controlling risk is a continuous four-step process, which returns to the first step once a control measure is implemented.
4-Step Risk Control Process
What is Good Site Planning?
Good site planning is the foundation for effective site management.
The entire workplace site should be considered when working out how to reduce the risks of harm to the environment associated with the storage and handling of liquid substances.
One effective strategy is to restrict certain activities or uses to specific areas or zones within the site. This reduces both the risk of environmental pollution as well as the costs associated with preventing such pollution.
An effective site plan should involve the following considerations:
- Include provision for storage locations that comply with workplace health and safety legislation, relevant Australian Standards, as well as the relevant state and territory WHS authorities - for example, storing liquids undercover.
- Undertake a review of the processes that take place on your site and, where possible, look for ways to reduce the volume of toxic and hazardous liquids.
- Invest in purpose-built, high-quality bunding installations to create secondary containment systems that comply with Australian regulations and prevents uncontained spills and leaks from occuring.
- Install appropriate site containment infrastructure and site isolation systems to ensure that hazardous liquids that are spilled or leaked cannot contaminate the environment, including the air, land and water (including groundwater).
- For water that does enter the environment from any uncovered outdoor work spaces, install systems - such as first flush systems, triple interceptor points, and oil/water separators - that guarantee the water is clean once it leaves the site.
- Ensure normal, uncontaminated stormwater is diverted away from the site’s liquid storage and other areas where contaminants can accumulate.
Drive-over floor bunding is an example of an effective secondary containment solution for spills and leaks
How to Manage Liquid Storage
The storage of liquid substances involves two fundamental measures of containment:
- Primary containment - which is mainly about where NOT to store liquids that could contaminate the environment if spilled or leaked, considering both the location and structure of the container used to store the liquid
- Secondary containment - which includes bunding and encasement solutions designed to contain liquid spills and leaks if the primary liquid storage container or transfer process fails
What are Primary Containment Measures?
Where you choose to store liquid substances on your site can have an enormous impact on the likelihood of an uncontained spill occurring.
- Situating liquids where the risk of environmental pollution is heightened (to either land or water) - such as in or on structures that sit above waterways, including boat sheds, pontoons and jetties
- Bare ground or earth and other unsealed surfaces
- Site areas without any provision for secondary containment
- Site areas close to stormwater inlets, drains, and creeks and rivers
- Site locations where the risk of polluting the water or contaminating the soil is low
- Areas inside buildings or structures that function as secondary containment areas - or bunded areas - to prevent spills escaping the site
- Undercover, rainproof, professionally sealed surfaces or floors with appropriate secondary containment or bunding equipment
- Bunded shelving solutions purpose-built for the type of liquid substances they hold - such as bunded polyethylene shelving for safely storing corrosive liquid chemicals
Top 10 Primary Containment Measures
Adhere to the following 10 primary containment measures to ensure safety and prevent environmental pollution caused by spills and leaks.
- Clearly label liquid containers and liquid stores with the proper, compliant signage and placarding.
- Segregate incompatible substances in dedicated, ventilated stores to avoid causing dangerous reactions.
- Use fit-for-purpose compliant storage containers with secure lids for all liquid substances, especially flammable liquids (avoid using food or beverage containers)
- Only purchase or order the minimal quantity of chemicals required for your site operations, and choose safer substitute products where possible.
- Adhere to safe decanting and pouring techniques to reduce the incidence of spills and splashing liquids (for example, use portable bunds or drip trays when decanting in an area without existing secondary containment measures in place).
- Properly dispose of liquid substances no longer used at your site (get advice from appropriate waste management authorities or service providers).
- Provide and maintain all necessary PPE, including gloves, face shields, safety glasses and respirators.
- Regularly monitor and maintain all primary containment systems and infrastructure at your site.
- Maintain an up-to-date inventory (register or manifest, as required) of all liquid substances kept on site
- Provide relevant updated Material Safety Data Sheets (MSDS) and Safety Data Sheets (SDS) kept in easily-accessible, secure document holders
What are Secondary Containment Measures?
Secondary containment measures are designed to prevent liquids escaping into the environment in the event of a leak or spill.
- Bunds or bunding - which are impermeable, raised barriers acting as the perimeter of a secondary containment area (such as walls, gutters or curbs, speed humps, and flexible barriers made from suitably constructed materials)
- Encasement - which involves storage with inbuilt or integral secondary containment (such as purpose-built bunded shelving or placing drums inside sealed plastic containers during transport)
- Grading - which involves grading sealed surfaces to create a contained area, using components of a building or external structure.
NOTE: If the area contains any drains leading to the stormwater system, it is not classed as secondary containment.
Secondary Containment installations can be permanent or temporary, fixed or mobile, inside or outdoors, and used for both minor (small container) and bulk tank storage.
What are the Design Considerations for Secondary Containment?
There are minimum requirements applicable to designing secondary containment areas, with more stringent requirements for the storage and handling of liquid substances classified as Dangerous Goods (as outlined in the ADG Code), such as Class 3: Flammable Liquids.
Standards Australia develop and maintain a series of standards relevant to the safe storage and handling of liquid substances, including hazardous chemicals and other dangerous substances. You should ensure that your secondary containment areas and equipment comply with all standards relevant to the liquids kept at your site, along with your state or territory’s WHS laws and regulations.
How to Determine Volume of Secondary Containment
The effective volume of your secondary containment installation is determined by a series of key factors, including the total volume of liquids being stored on site, and whether the area is used for tank vehicle loading.
Essentially, the bigger the volume of the secondary containment area relative to the volume of the primary storage containers, the lower the risk of uncontained leaks or spills occurring.
Consideration must also be given the proximity of primary liquid storage containers, such as drums, to the perimeter of the secondary containment area. For example, unless adequately restrained using fencing or racks, drums and tanks should be no closer to the perimeter (such as floor bunding) than half their height (the half height rule).
Drums should be stored in adherence to the half height rule
If a secondary containment area is not undercover and exposed to rainfall, additional volume is required (specific requirements taking into account climate and rainfall can be obtained from the Bureau of Meteorology)
How to Select Materials for Secondary Containment
Bunds and buildings used as secondary containment spaces must be waterproof - including the walls, flooring and roofing - using either impermeable construction materials or coatings.
Doorways and other openings must have suitable barriers installed, such as drive-over floor bunding, flexible bunding barriers or raised metal strip bunding, along with an effective procedure for promptly collecting and cleaning up leaks and spills.
If the secondary containment space is located outdoors, roofing that prevents rainwater from entering the area should be installed if possible. If roofing is not practical due to the size of the storage tanks or safety reasons, provision must be made for regular testing, storage and disposal of contaminated water that accumulates inside the secondary containment area.
Drive-over floor bunding can be installed at doorways and other openings
How to Monitor and Maintain Secondary Containment Systems
Secondary containment systems must be regularly inspected and properly maintained to ensure they perform effectively whenever required due to a leak or spill.
Consider the following factors when developing an inspection and maintenance schedule:
- Are your secondary containment areas being used properly for the purpose they were designed for? Are personnel leaving or using liquid containers outside the area or storing other unnecessary materials in the area and reducing its effective volume?
- Do not neglect to inspect and maintain the primary containers - check labels, signage, lids, etc. If primary containers are compromised, secondary containment becomes primary and there is no contingency for containing spills and leaks.
- Regularly inspect all secondary containment structures and equipment - check bund walls and floors, check seals, and look for damage or cracks in casings, and consider any changes to the area such new installations such as piping or signage that could compromise the integrity of secondary containment systems.
- Check switches, sensors, alarms and pumpsare in good working order.
- Check for the accumulation of rainwater or other uncontained liquids inside the secondary containment areas.
- Clean bund regularly
- Consider disposal of the liquid substance if it is no longer required and poses un unnecessary ongoing risk.
Part Two of How to Manage and Respond to Spills: A Complete Guide will guide you through the process of responding to leaks and spills of liquid substances in the workplace.
Dangerous goods storage specialists STOREMASTA have also developed an eBook covering the essentials of storing flammable liquids. You can download this free eBook, Essential Considerations When Storing Flammable Liquids Indoors, right now, and help ensure that you meet your compliance obligations.