Two examples of sites where oil and fuel could contaminate surface water:
There are two Classes of Separator:
Which type and class of Separator do I need?
CLASS 1 SEPARATORS
These are designed to achieve a discharge concentration of less than 5 mg/ litre of oil under standard test conditions and are required for discharges to surface water drains and the water environment. Many contain coalescing devices to trap oil droplets.
CLASS 2 SEPARATORS
These are designed to achieve a discharge concentration of less than 100 mg/litre of oil under standard test conditions and are suitable for dealing with discharges where a lower quality requirement applies. e.g. discharges to foul sewer.
Both classes can be produced as full retention or bypass separators.
Do I need Silt Capacity?
EA PPG3 clearly states; "On sites where high levels of silt are likely to enter the separator, the build up of silt must not be allowed to compromise the operation of either the separator or the by-pass device."
We therefore offer Separators with or without silt capacity and our large Silt Trap (see below) that can be installed upstream to meet EA requirements.
A Class 1 Full Retention Separator is required if you plan to discharge to surface water (i.e. river, watercourse, soakaway) and is the model we advise is installed for washpads situated away from the foul sewer.
A Class 2 Full Retention Separator is allowed for foul sewer discharges (but you must seek permission).
Use of detergents
It should be noted that the use of detergents (which emulsify the oil/water mix) should not be used in Separators that discharge to surface water.
Treats the full flow that can be delivered by the drainage system, normally equivalent to rainfall intensity of 65 mm/hour.
Bypass separator
Fully treats all flows generated by rainfall rates of up to 6.5 mm/hour (99% of all rainfall events). Flows above this rate are allowed to bypass the separator.
Forecourt separator
A full retention separator specified to retain on site the maximum spillage likely to occur at a petrol filling station. A separator with an oil storage capacity of 7600 litres is usually required.
Closure Devices
Full retention separators must be provided with an automatic closure device which operates in the event of a sudden surge of a large quantity of oil entering the system or too high an accumulation. This device should work in conjunction with the oil alarm.
Oil alarm
Separators must be provided with a visual and audible oil alarm (similar to the one shown here), remotely located if necessary. This operates when the oil level reaches 90% of the oil storage volume and indicates that the separator needs immediate emptying for it to continue to work effectively.
Click here to view our range of accessories
Accessories usually required to complete an installation are featured in this section.
What about Installation?
We offer a comprehensive range of all classes and types of Separators and accessories, competitively priced, to suit most needs with professional installation if required.
Our qualified engineers also carry out separator servicing and maintenance as required by EA PPG3 and with full certification (often an insurance requirement).
