from
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Pipework
You must ensure that any sight gauge is properly supported and fitted with a valve that closes automatically when it is not in use.
You must position any fill pipe, draw-off pipe or vent pipe to minimise the risk of damage. If any fill pipe, draw-off pipe or vent pipe is above ground, you must ensure that it is properly supported.
In England the vent pipe must be positioned to direct any spilt oil vertically downwards into the secondary containment system (SCS).
If any fill or draw-off pipe is underground, you must ensure that it:
* has no mechanical joints, except where you can access them for inspection
* is protected from physical damage
* has adequate facilities for detecting leaks.
Preventing leaks
If any underground fill or draw-off pipe is fitted with a leak detection device, you must maintain and test the device regularly to ensure that it works properly. In Scotland you must test detection devices at least every five years.
If any underground fill or draw-off pipe is not fitted with a leak detection device, you must test the pipe for leaks before it is first used. You must carry out further tests for leaks at least once every ten years, or in the case of pipes with mechanical joints, at least once every five years.
You must protect any metal fill pipes, draw-off pipes or overflow pipes, from corrosion. In Scotland, you must not use pipes that are permeable to hydrocarbon vapours.
If you can’t see the tank and any vent pipe from where the filling process is controlled, you must fit an automatic overfill prevention device. This could include an alarm or a fail safe device.
looks like double containment plastic then
i can put you in touch with old boss in Witney if you want????
) installing a big backup generator, underground.
