Cummins Logistics Warehouse Extension

Delivering ground stabilisation and earthworks engineering for a major commercial warehouse development

MGL Earthworks has recently delivered a major ground stabilisation and bulk earthworks package in Darlington, preparing a site for a new 280,000 sq ft logistics warehouse on behalf of Cummins. Working as a subcontractor to GMI Construction, the team transformed challenging ground conditions and created a high-quality development platform to support the expansion of the manufacturer’s established Darlington campus.

The project combined large-scale earthworks operations with the stabilisation of desiccated clay soils, allowing significant volumes of material to be reused on site and reducing the need for imported aggregates. With GMI Construction working to a demanding programme, it was crucial that the earthworks team delivered a compliant, high-quality platform within the 12-week construction timeframe.

Scope of the project

The project involved the delivery of a comprehensive earthworks package and also involved the excavation and off-site disposal of large volumes of unsuitable material. Attenuation crates were required to be supplied. To improve the earthworks balance and the disposal of excess material, the site platform was required to be raised by 335mm.

Managing environmental constraints and providing ground engineering solutions

MGL Earthworks faced two unique challenges during delivery: nesting birds occupying 33% of the site area and the presence of desiccated clays beneath established trees.

To progress the works, the team worked in daily consultation with an ecologist who identified which areas could be cleared and which needed to remain protected. This required the programme to be re-sequenced, with works continually adapted to maintain progress and achieve the 12-week delivery programme.

Established tree roots had drawn significant moisture from the underlying clay, creating desiccated ground conditions that required over-excavation beneath the affected areas.

Rather than excavating and disposing of the clay off-site before replacing it with imported aggregate, the team reconditioned the material on site by lime modification, reintroducing moisture and reusing it as engineered fill. This approach reduced waste, minimised imported materials and delivered significant programme and cost savings.

The effectiveness of this approach was a key factor in securing the project, with the client recognising the value of MGL Earthworks’ strategy for overcoming the challenges associated with desiccated clays.

Delivering works on time despite logistical challenges

Across the programme, the earthworks team excavated 12,000 m³  of topsoil, of which 7,600 m³  was disposed off-site. The team also imported and placed 15,000 tonnes of type 1 aggregate material throughout the programme. Delivering this operation required careful logistical planning to coordinate the export and import of materials whilst maintaining progress and keeping the project on schedule.

Through the utilisation of site-won materials, the team adjusted the construction build-up to incorporate a sub-base replacement stabilisation (SBR) layer. By treating site-won materials with a cement binder, MGL Earthworks was able to create a suitable engineered layer whilst reducing the need for imported aggregates.

By optimising the earthworks balance and reducing imported material requirements, the project generated fewer HGV movements, helping to lower noise impacts, reduce site traffic and minimise disruption to the surrounding area throughout the programme.

Another success came from working closely with the client’s designers to optimise the attenuation crate system design, reducing both project costs and the volume of imported aggregate required for bedding and surround materials.

The team also provided sample materials to enable the client and designer to select the most appropriate aggregate specification, balancing performance, durability and cost requirements.

From the outset, MGL Earthworks engaged with key stakeholders to develop the most efficient delivery strategy, supported by detailed topographical surveys and 3D modelling. Weekly coordination meetings with the client and project team helped mitigate potential delays, maintain programme certainty and ensure efficient handover to follow-on trades.

Delivering a compliant solution

MGL Earthworks developed and delivered a compliant solution while managing ground-related risks associated with desiccated clays, earthworks balance and material quantities. Managing these risks was crucial to maintaining programme.

Successful project delivery

The project represented one of MGL Earthworks’ largest logistics-focused earthworks programmes to date, demonstrating the team’s ability to successfully manage complex material movements whilst delivering a high-quality finished platform within a constrained programme.

Across the programme, MGL Earthworks:

• Topsoil stripped 12,105m³ of material

• Disposed of 15,310 tonnes of topsoil

• Undertook 43,792m³ of cut-and-fill operations

Modified 21,980m3 of dessicated material

• Stabilised 15,762m³ of site-won materials, significantly reducing imported material requirements

• Imported and placed 15,536 tonnes of Type 1 stone to create a stable construction platform

• Supplied and installed 3,830m³ of attenuation crates

• Supplied 3,308 tonnes of 20mm pipe bedding from MGL Group’s own soil wash plant

• Supplied and installed 154 linear metres of precast concrete retaining wall

This programme also reinforced the value of MGL Group’s circular economy approach, with 3,308 tonnes of 20mm pipe bedding supplied from our own soil wash plant. By reusing recycled materials within the Group, the project reduced reliance on virgin aggregates, minimised waste and reduced transportation requirements.

Additional social value was created through the use of local labour, regional plant hire companies and North East supply chain partners, helping to support employment and economic activity within the local economy.

MGL Earthworks successfully delivered the works on time, on budget and to the required quality standards, providing a platform that enabled the client to progress the next phase of development with confidence.