The document "Guidance for Pollution Prevention: Use and Design of Oil Separators in Surface Water Drainage Systems (GPP 3)" focuses on the correct application and installation of oil separators to prevent pollution from surface water drainage. Oil separators, often used in areas with potential oil contamination risks such as car parks or industrial sites, play a vital role in separating oil from water and preventing environmental damage.
This guide is relevant for businesses across Northern Ireland, Scotland, and Wales, with specific legal requirements and design standards aimed at minimising pollution risks. Below is an in-depth summary of the key topics covered in this document.
Importance of Oil Separators
Oil separators (also called oil interceptors) are essential for removing oils from surface water drainage, protecting watercourses, groundwater, and sewage treatment systems. These systems are particularly important where oils could leak into water sources from industrial activities, vehicle maintenance areas, or forecourts. The separators are designed to capture and store oil before water enters the environment or is treated.
Separators are crucial for businesses that deal with oils or hazardous substances, as any discharge of contaminated water could lead to legal consequences, including fines, penalties, and reputation damage.
Legal Requirements for Oil Separators
Compliance with environmental laws is essential for businesses that handle oil. The guide points out the varying regulations in Northern Ireland, Scotland, and Wales. It is critical to understand local environmental laws to avoid criminal offenses, which could include penalties like fines, clean-up costs, or even imprisonment in extreme cases. Businesses should consult with local environmental regulators early when considering installing oil separators, as formal approval may take up to four months.
Moreover, the guide emphasises the importance of understanding the risks of oil pollution and the pathway by which contaminants could reach water sources. Companies must also ensure they are properly educated on the local drainage network to avoid accidentally discharging into surface water.
Where Oil Separators Are Used
Oil separators are typically used in areas where there is a high risk of oil contamination. These areas may include:
- Car parks with more than 50 spaces or covering an area larger than 800m²
- Industrial sites where oil is stored or used
- Petrol station forecourts or other refueling sites
- Vehicle maintenance areas
The document also discusses the integration of Sustainable Drainage Systems (SuDS) in combination with oil separators. SuDS can reduce the environmental impact of a site by controlling pollution from surface water runoff. While SuDS may provide sufficient pollution control for low-risk sites, oil separators are recommended for higher-risk areas.
Types of Oil Separators
The guide details the types and classifications of oil separators according to European standards (BS EN 858-1:2002 and BS EN 858-2:2003). These standards define the performance and maintenance requirements for oil separators:
- Class 1 Separators: Designed to achieve a discharge concentration of less than 5 mg/l of oil, required for discharges to surface water drains.
- Class 2 Separators: Achieve a discharge concentration of less than 100 mg/l and are suitable for discharges into the foul sewer system.
Additionally, the document covers full retention separators and bypass separators:
- Full retention separators treat all the water entering the drainage system and are used where there is a significant risk of oil contamination.
- Bypass separators are designed to treat lower flow rates during moderate rainfall and are often used in low-risk areas such as car parks.
Installation, Labelling, and Maintenance
Correct installation is critical to the effectiveness of oil separators. The guide recommends that businesses seek advice from sewer providers and environmental regulators before installation to ensure that the selected separator meets all the necessary environmental standards.
Each oil separator must be labelled with specific details, including the manufacturer's reference, oil storage capacity, and the separator's nominal size. Proper labelling and a drainage plan that clearly indicates the location of all separators are required.
Once installed, separators must be regularly inspected and maintained. Routine checks include assessing oil and silt levels, servicing alarms, and ensuring that any coalescing devices are functioning correctly. Failure to maintain the separators can lead to pollution incidents, and separators should be emptied and serviced when oil levels reach 90% capacity. Regular maintenance is essential to ensure that separators continue to operate effectively, preventing costly pollution incidents.
Spill Response and Waste Management
Despite preventative measures, spills can still happen. The document outlines the need for businesses to have an incident response plan in place. This plan should include a list of key contacts, reporting procedures, and the location of spill equipment. Employees should be trained to respond to incidents quickly to mitigate environmental harm.
Managing the waste from oil separators is another key aspect of pollution prevention. Under the Duty of Care regulations, businesses are responsible for ensuring that waste, such as silt and oil collected from separators, is stored, transported, and disposed of legally. Businesses must work with registered waste carriers and ensure that hazardous waste is disposed of correctly.
In conclusion, the Guidance for Pollution Prevention offers vital information for businesses handling oil to protect the environment, comply with legal requirements, and avoid the financial and reputational damage associated with pollution incidents. By installing, maintaining, and properly using oil separators, businesses can significantly reduce their environmental impact and manage pollution risks effectively.