Ground Investigation of Potential Hydrocarbon Pollution

Investigation of Potential Hydrocarbon Pollution and Presence of Buried Structures

Ground Projects were appointed to supervise an intrusive site investigation to support the sale and residential development of a former petrol station.

Historical photography showed evidence of a former petrol station with previously unknown infrastructure that was not present on publicly available historical maps. Given this lack of information regarding the condition, and indeed presence, of petrol storage tanks, the potential for existing and future hydrocarbon contamination was considered a high risk and needed addressing prior to development.

GPCL reviewed existing SI data, such as a factual Ground Investigation report and geophysical survey. We identified two possible buried structures and designed a suitable site investigation utilising Windowless Sampling and hand dug pits to investigate these areas in a way that would minimise the risk of disturbing any contaminants present and creating new pathways for hydrocarbon migration.

An added constraint was the requirement to minimise ground disturbance next to a busy road. GPCL commissioned and supervised the investigation by an experienced and qualified GI contractor.

The ground investigation resulted in the identification of a previously unknown petrol tank buried beneath an area of hardstanding. The GPCL engineer on site logged the geology encountered, took environmental samples of material around the exposed tank to determine the extent of any hydrocarbon contamination and surveyed the location of the tank and other buried structures encountered.

These findings were communicated to the client in the form of a letter report for inclusion in a sales pack.