First Establish What Is There
Gather old plans, delivery records and any previous inspection or decommissioning documents. Note visible fill and vent points without opening chambers or disturbing buried pipework. A tank’s apparent size above ground may reveal little about its buried footprint, and an old drawing may not show later alterations.
If the tank is discovered during building work, pause activity around it and arrange a competent assessment. Tell the contractor if there is oil odour, stained soil or water collecting nearby. Unknown contents should be treated as an uncertainty to resolve, rather than assuming an old heating tank contains nothing significant.
Removal Or Leaving The Tank In Place?
Removal allows the tank to leave the site and may make the excavation available for inspection. It also brings excavation, lifting and reinstatement requirements. Nearby foundations, buried services and limited machine access can make this more involved than an above-ground oil tank removal.
In-place decommissioning can be considered where removal is impractical, subject to site assessment and the relevant environmental or planning requirements. It does not mean covering an untreated tank and forgetting it. Environment Agency guidance sets out the need for a safe decommissioning approach and records when tanks remain underground.
Contents And Cleaning Come First
The tank and connected lines need an agreed isolation plan. Remaining fuel, contaminated water and sludge must be identified and removed through suitable handling arrangements. A gauge showing empty is not confirmation that low points are dry, especially where the tank has been unused and water has entered over time.
Cleaning and atmospheric assessment inform the next operation. Any proposal to fill a tank should explain preparation, filling material, how the work will be checked and the future use of the ground. The method should be selected for the actual tank and setting, rather than sold as an automatic solution for every buried vessel.
Excavation And Ground Conditions
Provide the tank location in relation to buildings, boundaries and access roads. Excavation planning needs information about underground services and how machinery can reach the area. Nearby structures, water ingress, the stability of excavated sides and the location of stored spoil can all influence the safe working arrangement.
A garden route may admit hoses but not an excavator or lifting vehicle. A commercial forecourt may have better vehicle access but more buried connections and operational restrictions. Agree what will be opened, how it will be protected during the work and what standard of backfill or surface reinstatement is included.
Do Not Lose The Contamination Question
Oil may have escaped before the tank was discovered or before a visible leak became apparent. Tank removal, cleaning or filling does not by itself answer whether soil or groundwater has been affected. If there is evidence or suspicion, a separate environmental investigation may be needed alongside the tank works.
Tell your insurer about a suspected insured loss and retain relevant correspondence. For development land, coordinate with the project’s environmental adviser and planning conditions. Avoid commissioning final reinstatement too early if it would prevent access needed for investigation, sampling or additional work on affected ground.
Prepare A Useful Enquiry And Record
Send the postcode, plans, photographs of accessible surface fittings, known fuel history and the reason for the work. Include whether the tank is active, the likely remaining volume, any nearby water or drains and the route for machinery. Do not enter a chamber or tank to improve the information supplied.
Cost is driven by investigation, fuel recovery, cleaning, excavation, access, lifting, waste and reinstatement. Ask for the tank location, treatment method and remaining features to be recorded at completion. Where a tank stays in place, keep that information with the property documents so future owners and contractors know what is beneath the surface.
Common Questions
Can An Underground Tank Simply Be Filled?
Underground tank filling requires assessment and preparation before a suitable method is agreed. Remaining fuel, water, sludge and connections must be addressed, and the condition of the surrounding ground considered separately. Filling an untreated tank can leave unresolved hazards and poor records, so ask for a written decommissioning scope and completion evidence.
Will Removing The Tank Resolve A Property Sale Query?
Underground tank removal can answer part of a property sale query, but the buyer may also need location records, waste documents and evidence about ground condition. Ask your solicitor what information is required before booking. A disposal record for the tank cannot establish on its own whether historic contamination exists beneath or around it.
Tell Us About Your Tank
A postcode, photographs of the installation and an outline of the access are a useful starting point. Mention any suspected leak at the start of your enquiry.
Send A Tank Enquiry