Bunds require testing at regular intervals to ensure continued protection of the tanks, drums and other vessels contained therein. In general, the EPA and local authorities require testing every three years.
Bund testing (sometimes referred to as Bund Integrity Testing) is usually carried out by means of a water retention test. This involves filling the bund to a predefined level and measuring the drop in level over a defined time period. Adjustments are made for rainfall and evaporation.
CIRIA 163 is a bund test protocol specifically intended for bunds and is a six hour test. As the test can be carried out in one working day this reduces the cost and environmental risks compared to BS8007 (see below). Environmental Efficiency performs most bund integrity tests using CIRIA 163 and this is accepted by the EPA.
The traditional bund test protocol is BS8007. However, this standard is intended for concrete water retaining structures such as reservoirs and not secondary containment of hazardous liquids. Testing to BS8007 is generally for a period of 7 to 10 days. This leads to the creation of an unintended environmental risk in that should the tanks in the bund fail, then as the bund is full of test water, the bund will overflow and thus create an environmental incident.
Where the bund cannot be filled with water to capacity, the EPA allows a visual inspection of the bund by a Chartered Engineer; Environmental Efficiency can undertake this. Where a visual inspection is required, Environmental Efficiency will often carry out a water retention test to a low level (typically 100 mm) to test the floor and the wall/floor joint and a visual inspection of the rest of the bund.
Where entry into bunds is required, consideration needs to be given as to whether the bund is a Confined Space. Where entry into a confined space is necessary, Environmental Efficiency will use staff with Confined Space Certificates.
All Environmental Efficiency staff used for bund testing will have Safe Passes and Manual Handling Certificates.