Spill from Sight Gauge
The sight gauge of the kerosene domestic heating oil tank had dislodged, causing an estimated 1200 litres of oil to be lost to ground. At the time of the spill the oil tank was located at the rear of the detached garage, a distance of 10 metres from the dwelling. Soon after the spill odours of oil were noted in the dwelling
Intrusive investigations at the site identified an extensive area of soils impacted with oil at the rear of the garage, close to the side wall of the garage, and between the garage and dwelling. There were odours of oil and staining of internal walls in the garage and in the dwelling. Following excavation of external soils, further intrusive investigation in the dwelling and garage were undertaken revealing that soils under the garage, kitchen, dining room, and hallway were heavily impacted with oil and the oil had soaked into the floors.
Risks and Remediation
To restore the amenity of the garden and to reduce the risk of further oil migration to the garage and dwelling, the oil impacted external soils were excavated. The works revealed that oil had followed the foundations of the garage and had further migrated around drain channels. It was also found that a storm drain had provided the main route for oil to migrate under the dwelling. The floors of the garage and affected rooms in the dwelling were broken out and underlying fill materials and soil was excavated to 1m below ground level.
Footings and foundations of the external and internal walls were scrubbed with surfactant. Severely oil impacted bricks and blocks were replaced.
Excavated soils, removed building materials, and captured oily water were sent for disposal to a licensed facility.
Due to the extensive nature of the works the homeowners moved out until reinstatement was complete.
Excavations in the garden, dwelling, and garage were back filled with clean imported soil or back fill material as appropriate. A specialist building contractor undertook reinstatement of turf, paving slabs, the garage drive, floors of the dwelling and garage, and decorative work.
Validation was by field monitoring and submission of soil and air samples for analysis at a UKAS accredited laboratory.Back