Case Study: Proposed New Lidl Supermarket, Middlesbrough
Client: Lidl GB Ltd
Services: Window sample boreholes, trial pits, chemical testing, ground gas monitoring, geotechnical and geoenvironmental investigation
Location: Linthorpe, Middlesbrough
Project summary & client purpose:
Earth Environmental & Geotechnical was commissioned by Lidl GB Ltd to undertake an additional geoenvironmental site investigation at Green Lane, Linthorpe, Middlesbrough, to support the proposed development of a new Lidl supermarket and associated infrastructure.
The purpose of the investigation was to further assess ground conditions following demolition works, with a focus on soil contamination, ground gas and geotechnical suitability for the proposed commercial development. The findings were required to support planning, foundation design and future construction activities while ensuring compliance with current environmental and regulatory guidance.
Our services:
We delivered a targeted programme of geoenvironmental investigation works across the site, including window sample boreholes, trial pits, ground gas monitoring and environmental laboratory testing.
The investigation included four window sample boreholes to depths of 4.45m below ground level, installation of groundwater and gas monitoring standpipes, and multiple trial pits within the proposed building footprint and loading bay areas. Soil samples were collected and analysed for a wide range of contaminants including metals, hydrocarbons (TPH), polycyclic aromatic hydrocarbons (PAHs), sulphates and asbestos.
Ground conditions were logged in accordance with current British Standards and all findings were compiled into a comprehensive interpretative report, providing practical recommendations relating to contamination risk, ground gas protection and foundation design.
The challenges:
The site had previously undergone demolition works, introducing uncertainty regarding the extent and variability of made ground and the condition of any remaining buried structures or foundations.
Variable made ground deposits were encountered across the site, with depths ranging up to 1.90m below ground level in some areas. Groundwater was also encountered within multiple boreholes, requiring careful assessment of potential risks to future development and construction activities.
The challenge was to obtain reliable and representative environmental and geotechnical data across the site to confirm its suitability for commercial redevelopment, while identifying any localised risks associated with contamination, ground gas or former site use.
Results:
The investigation confirmed that the site is suitable for the proposed commercial development, with no contaminant concentrations identified above the relevant screening criteria for a commercial end use.
No asbestos fibres or fragments were detected within the soil samples tested, and the overall contamination risk to future site users was assessed as very low. Ground gas monitoring classified the site as Characteristic Situation 1 (CS1), indicating a very low gas risk and confirming that no specific gas protection measures are required for the proposed development.
Geotechnical assessment confirmed that foundations can be constructed within competent natural clay strata beneath the made ground deposits, providing the client with clear and practical guidance for the next stages of design and construction.
Overall, the findings enabled Lidl GB Ltd to progress the redevelopment proposals with confidence while reducing uncertainty surrounding ground-related environmental and geotechnical risks.
