Ground Investigation – Sinkholes, Solution Features & Gulls

With the recent bad weather issues, Kent and Sussex have had more than their fair share of geotechnical complications in the form of sinkholes, solution features, gulls and other voids appearing in the ground and swallowing up surface structures.

Southern Testing were asked to assist one of our clients with a particularly awkward gull which had swallowed up a section of the main road through a picturesque Kentish town: the hole had been successfully backfilled as far as could be seen but the extent of the subterranean void was unknown and access at the surface was limited.

Our lightweight Geo 205 rig was the tool for the job! With its small surface footprint (less than 15m2, inclusive of ancillary equipment) we could get it over the required area and chase the geological profile down to the required depth of 30m, casing off the upper 6m of overburden and achieving full core recovery to depth, in 1.5m runs.

This enabled our client to obtain information from a section of the site which might have been inaccessible to a more conventional, heavy framed rig, whilst maintaining the required core diameter to assist the engineers with their logging.