In today's industrial landscape, environmental protection has become a paramount concern. Secondary containment systems play a vital role in preventing hazardous chemical spills and leaks that could potentially pollute soil, water, and the surrounding ecosystem. This article provides a comprehensive overview of secondary containment systems, including their purpose, components, regulatory requirements, and best practices. Whether you are a facility owner, operator, or simply interested in environmental sustainability, understanding the importance and implementation of secondary containment systems is essential for safeguarding our planet.

1. Definition and Purpose
Secondary containment refers to the preventive measures taken to confine and control hazardous substances in the event of a storage tank failure, piping breach, or accidental spill. The primary objective of a secondary containment system is to contain and isolate any leaked or spilled substances, preventing their migration into the environment. These systems act as a crucial barrier between potential pollutants and the surrounding ecosystem, minimizing the risk of contamination and protecting human health, wildlife, and natural resources.

2. Components of a Secondary Containment System
A well-designed secondary containment system typically consists of several key components. These include:

a) Containment Structure: The containment structure is the primary physical barrier that surrounds the storage tanks or vessels. It can be constructed of concrete, steel, fiberglass, or other impermeable materials. The structure should be designed to withstand the anticipated load, including the weight of the stored substances and environmental factors such as seismic activity.

b) Secondary Containment Liner: The liner is typically a chemically resistant material that is installed within the containment structure to prevent any potential leaks or spills from reaching the environment. Common liner materials include high-density polyethylene (HDPE), reinforced polyethylene, or polyvinyl chloride (PVC) geomembranes.

c) Leak Detection and Monitoring Systems: To ensure the integrity of the secondary containment system, leak detection and monitoring systems are essential. These systems can include sensors, alarms, and automated monitoring devices that detect leaks, spills, or any changes in fluid levels within the containment area.

3. Regulatory Requirements and Compliance
Governmental agencies, such as the Environmental Protection Agency (EPA) in the United States, have established regulations and guidelines for the installation and maintenance of secondary containment systems. These regulations vary depending on the industry, the type of hazardous materials being stored, and the size of the facility. It is crucial for facility owners and operators to familiarize themselves with their specific compliance requirements to avoid potential penalties and environmental harm.

4. Best Practices for Design and Installation
Implementing a high-quality secondary containment system requires careful planning and adherence to best practices. Some key considerations include:

a) Site Assessment: Conduct a thorough site assessment to identify potential risks, including soil conditions, drainage patterns, and proximity to water sources. This assessment will help determine the appropriate size and type of containment system required.

b) Proper Design: Work with experienced engineers and consultants to design a secondary containment system that meets regulatory requirements and industry best practices. Consider factors like load capacity, expansion joints, and proper drainage.

c) Regular Inspection and Maintenance: Establish a routine maintenance and inspection program to ensure the integrity of the containment system. Inspections should include checking for cracks, leaks, or deterioration, as well as verifying the effectiveness of leak detection and monitoring systems.

5. Types of Secondary Containment Systems
Secondary containment systems can vary depending on the specific application and industry. Some commonly used systems include:

a) Berms or Dikes: These earthen or concrete barriers are commonly used for bulk storage tanks, creating a surrounding wall that contains any potential spills or leaks.

b) Double-Walled Tanks: These tanks consist of an inner storage tank surrounded by an outer containment shell. In case of a leak or failure of the inner tank, the outer shell acts as a secondary barrier, preventing any leakage from reaching the environment.

c) Spill Trays and Pans: Typically used for smaller containers, spill trays and pans provide a containment area directly beneath the storage or handling equipment, capturing any spills or leaks.


Secondary containment systems are vital safeguards against potential environmental disasters caused by hazardous chemical spills and leaks. By understanding the purpose, components, and best practices associated with these systems, facilities can effectively mitigate risks and protect the environment. Compliance with regulatory requirements and regular maintenance and inspection are crucial for ensuring the integrity of these systems. By prioritizing the implementation and maintenance of secondary containment systems, we can collectively contribute to a more sustainable and eco-friendly future.