Details

Geo-environmental Ground Investigation to determine underlying ground conditions on a disused historic landfill site which was redeveloped and landscaped in the 1980s to become a leisure park known as Festival Park.

The works comprised of a range of exploratory holes including rota-sonic drilling holes, trial pits and trenches, in-situ testing and monitoring, permeability testing, geotechnical and chemical laboratory testing and factual report.

Sonic drilling techniques were applied to the overburden/superficial deposits of the site with SPT testing undertaken every 3m and downhole magnetometer surveying carried out up to 30m depth to establish the presence of any UXO in the beach deposits below the Madeground. Once rockhead was established conventional drilling techniques were applied to core and extend the boreholes to establish the competency of the underlying Sherwood Sandstone.

All boreholes were fitted with 50mm diameter ground gas and ground water monitoring instrumentation and data loggers to facilitate long term monitoring of the site.

Suites of both geotechnical and chemical analysis and testing are currently underway in our in house geotechnical laboratory and our preferred environmental laboratory ALS

Rotary rig set up on site in front of a building

Challenges 

The site was classified as a BDA RED Contaminated site. Clean drilling techniques had to be applied to each borehole to prevent the downward migration of any contamination as the boreholes were progressed. Concept are using reducing diameter casing strings and tooling with environmental seals to ensure aquifer protection as well constant gas monitoring during drilling.

To add to the challenges of drilling through the Madeground and superficial deposits Concept were instructed to carry our in situ SPT’s every 3m in the Madeground and a magnetometer survey throughout the underlying Beach Deposits between 20 and 30m.

Outcome

Concept are currently still on this site, however, all of our operations are being carried out to the satisfaction of the Investigation Supervisor, Arup and the Delivery Manager Wilmot Dixon and the ultimate Client Liverpool City Council. Through open, honest and transparent communication we have developed excellent rapport and relationships with all concerned parties. The site works are on programme and budget.

Location
Liverpool

Value
£525,000

Designer/Consultant
Arup/Willmott Dixon Construction Ltd

Client
Liverpool City Council