INLAND OIL SPILL CASE STUDY
COMPLEX STRUCTURAL REMEDIATION AFTER A KEROSENE SPILL Introduction Dealing with inland spill incidents is often not as straightforward as you might think, with input required from numerous parties to ensure the safe completion of remediation works in compliance with a wide range of legislation. This case study highlights how complex inland spill incidents can be, and how when dealing with these types of incidents, you need to ensure you seek expert advice. Oracle Environmental Experts Ltd were appointed to remediate a devastating heating oil (kerosene) spill that occurred in a 16th Century Grade II Listed property set in the West Sussex countryside. Internal kerosene impact was identified in the kitchen and hallway at the property requiring extensive excavation works. Additionally, the kerosene had migrated vertically and impacted two stone walls of the cellar located below the kitchen and dining room. A combination of detailed intrusive investigations, deep excavations and highly complex structural replacement were undertaken over the course of 4 months to restore residential amenity to the property.
odour. Based on delivery and consumption records, it was estimated that over 1000 litres of kerosene had been lost as a result of the spill incident.
Initial Visit and Emergency Mitigation Oracle Environmental Experts initially attended the property to assess the extent of kerosene impact and to install an air mover to reduce the elevated volatile organic compound (VOC) concentrations within the dwelling. The VOCs recorded in the ambient air of the property reached a maximum concentration of 51 parts per million (ppm) in the cellar prior to installation of an air mover. Lime plaster on the stained wall was removed to reveal a concrete block construction. It was evident from the VOCs released from the wall that it was saturated with kerosene, and the wall was subsequently covered and sealed with membrane to contain the vapours. Following OEE’s initial visit, it was clear that further intrusive investigation was required to delineate the extent of kerosene impact to the soils below the property and to the structures within the property.
Incident Summary At the start of the summer in 2019, the homeowner noticed strong oil odours in her property, particularly within the kitchen. After contacting her local OFTEC registered engineer, an oil leak was discovered from a failure on the oil feed line where it entered the Aga in the kitchen. The homeowner then noticed that a large ‘damp’ stain had appeared on a wall in the hallway which emitted a strong oil
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Investigation 5 no. trial pits were progressed through the floor of the kitchen to establish the extent of kerosene impact and the nature of soils below. The first trial pit (TP-1) was progressed at the spill origin in the kitchen adjacent to the Aga. A corehole was initially progressed through a 0.1 m thick concrete floor slab and was screened
