Inspection of oil tanks and other storage tanks according to VLAREM II

Inspections at companies

The inspection of a professional storage tank (e.g. oil tank, gas tank, etc.) is carried out by a certified environmental expert. This person operates according to the principles described in VLAREM II and is recognised by the Department of the Environment. This "Flemish Regulation on Environmental Permits" (VLAREM) outlines all the conditions for inspecting storage tanks in detail. We briefly summarize them for you, but first, let’s highlight the importance of an inspected tank.

Why inspect an oil tank or other storage tanks?

There are several reasons why your storage tank should be inspected regularly. Failing to have it inspected on time can have severe consequences: not only for the environment but also for your wallet.

• Prevent environmental fines
  Inspections are mandatory according to VLAREM II, since August 1, 1995.
• Possibility for an environmental permit
  When applying for a new environmental permit, the inspection certificates of the storage tanks will be requested. Without these certificates, a new permit will not be issued.
• Insurance coverage in case of damage 
  An approved storage tank also ensures that your company remains compliant with insurance coverage for all installations (ie.g., in the case of fire or environmental damage).
• Good operational condition 
  An inspection of the storage tanks ensures that all components are checked for proper functioning.
• Positive image towards stakeholders
  Organisations that are compliant with all their legally required environmental inspections are more likely to attract large investors..

Artion possesses the knowledge and expertise of all the different regulations and inspections related to technical installations. They ensure that companies are compliant with their inspections and documents for various types of storage tanks. In this way, companies are fully relieved. This can range from heating oil tanks, gas tanks, nitrogen tanks, to even nitric acid tanks, hydrochloric acid tanks, and sulfuric acid tanks. Below, we explain the most common tank inspections at companies.

Have your company's storage tank inspected

General inspection versus limited inspection

The general inspection includes the limited inspection supplemented with, among other things, a density test for underground tanks and an internal inspection for aboveground tanks. The limited inspection includes, among other things, checking the condition of the overfill protection; reviewing all valid documents (environmental permit, certificate of conformity, commissioning certificate, inspection certificates); checking for the presence of water and sludge; inspecting valves, pipes, pumps, etc.; inspecting the leak detection system; checking cathodic protection if applicable; ...

Density test for underground fuel tanks

During the general 15-year inspection, the tank should be subjected to a density test. There are several methods for this. A commonly used method is the ultrasound density test. First, two sound-sensitive sensors are placed in the tank. One sensor is positioned at the liquid level and the other sensor is positioned above the liquid level. The entire tank and pipes are then subjected to slight negative pressure. If sound is detected, it indicates a leak in the tank or pipes.

Internal inspection for general inspection

During the general 20-year examination, an internal inspection is required for tanks with a capacity of 20,000 litres or more, when it is impossible to inspect all the walls of the tank (e.g., a flat bottom in a vertical tank). For this, the tank must be emptied and cleaned beforehand.

Difference between private and professional gas oil tank

Although in many cases the same product is stored, there is a difference in regulations regarding the inspection of these tanks. A private tank may also be inspected by a certified heating oil technician. The inspection frequency for underground tanks is 5 years, and for aboveground tanks, it is a one-time inspection.

Most common tank inspections for companies

A new storage tank should undergo a commissioning inspection after installation and before being put into service.
After that, periodic inspections must be carried out, as listed below.

Hazardous liquids

• Fuels
  • Diesel tank (with distribution hose)
  • Gas oil tank
  • Mazout tank or fuel oil tank
    
• Corrosive substances
  • Sulphuric acid tank (e.g. in air scrubbing)
  • Hydrochloric acid tank (e.g. in water treatment)
  • Nitric acid tank (e.g. in manure treatment)
  • ...
    
• Frequency inspection
  • Underground tank
    • Limited examination: 2 annually
    • General examination: 15 annually (including tightness test)
    • In water catchment areas
      • Limited inspection: annually
      • General investigation: 10 annually
  • Above-ground tank
    • Limited survey: 3 annually
    • General investigation: 20 annually

Hazardous gases

• Compressed gases
  • Compressed air holder at compressor
    
• Hazardous gases
  • Propane gas tank
  • Nitrogen tank
  • Oxygen tank
  • Argon tank
  • CO2 tank
  • ...
    
• Frequency inspection
  • Underground tank and above-ground tank
    • 5 annually
    • Additional annual inspection for measuring cathodic protection
  • Above-ground tank
    • 5 annually

Identification plate for tank inspections

After each inspection, the storage tank is provided with a identification plate.
This identification plate can have the following colours:

GREEN

• Approved
  • Valid for 3 years (above-ground tank)
  • Valid for 2 years (underground tank)

ORANGE

• Defects may give rise to emergency situations
  • Valid for 6 months

RED

• Rejected
  • The defects must be resolved, if possible, before the tank can be refilled.

What class does your heating oil tank belong to?

There are different classes for permits issued after an approved heating oil tank.
The VLAREM permit is granted by either the province or by the municipality,
depending on the size of the heating oil tank.

Class I

• Provincial
• from 500.000 kg
• large industrial companies or port companies
  

Class II

• Municipality
• 20.000-25.000 kg
• e.g. SMEs and petrol stations
  

Class III

• Only notification of 100 kg up to 20.000 kg