Hospital Ground Investigation Completed Across Three Phases

Geocore is proud to highlight the successful completion of a three-phase ground investigation project at a Yorkshire Hospital, delivered in partnership with our valued client, Curtins Consulting. Spanning over two years, the works required careful planning, technical expertise, and close coordination to operate safely and efficiently within a busy, live hospital environment.

Phase 1 – February 2024

Geocore was initially commissioned to undertake a complex geotechnical investigation across the hospital site. The project brought together multiple specialist teams, each contributing their expertise to deliver a comprehensive subsurface assessment.

The scope of works included rotary drilling, windowless sampling, and hand pitting, using a range of equipment including compact tracked rigs to suit the constrained nature of the site. A key challenge encountered throughout the programme was the presence of artesian groundwater in nearly every borehole. This pressurised groundwater created conditions that could destabilise boreholes and compromise sampling accuracy.

To overcome this, Geocore deployed the Comacchio 405 drilling rig using air mist drilling techniques. This method, combining compressed air and water mist, proved highly effective in managing groundwater inflow while maintaining borehole stability and sample integrity.

In addition to rotary works, the team completed 50 windowless sample boreholes, most of which were fitted with monitoring installations for gas and groundwater. A further 24 hand-dug pits were excavated, including 18 utilising TRL probes for precise near-surface data collection.

Phase 2 – May 2025

Following the success of Phase 1, Geocore was re-engaged by Curtins to carry out a second phase of investigation works to support the hospital’s ongoing development plans.

This phase involved two site teams operating simultaneously and included both rotary drilling and window sampling techniques. Four rotary cored boreholes were advanced to depths of up to 30 metres using the Comacchio 405 rig with air mist flushing. The boreholes were designed to assess anticipated rock strata, with Standard Penetration Tests conducted at regular intervals to ensure data accuracy. Three boreholes were completed to full depth and secured with flush covers for long-term monitoring.

Complementing the rotary works, 17 window sample boreholes were installed to 5 metres depth using compact rigs to access restricted areas. Eight dynamic probe boreholes were also completed, with SPTs undertaken at 1-metre intervals.

Working within the hospital’s operational environment presented logistical challenges, particularly within the car park areas. To support operations, Geocore subcontracted a Vac-Ex team to assist with breaking out borehole positions and facilitating manual excavation. Despite restricted access and the need to minimise disruption to hospital operations, the project was delivered on programme, with excellent client feedback highlighting the team’s professionalism and adaptability.

Phase 3 – May 2026

The final phase of works further expanded the scope and complexity of the investigation, requiring a seven-week programme on site.

Geocore undertook six rotary cored boreholes ranging from 25 to 40 metres below ground level, alongside three rotary open-hole boreholes to approximately 15 metres depth. Standard Penetration Tests were conducted from shallow depths through to refusal in competent rock, ensuring consistent and reliable geotechnical data.

All boreholes were drilled using air-mist flushing techniques, with groundwater monitoring wells installed to support long-term observation. In addition, vibrating wire piezometers were installed using specialist non-shrink grout, enabling precise groundwater pressure monitoring.

The works were carried out using a Comacchio 602 rig, with site logistics presenting ongoing challenges. Operating within a live hospital environment required careful coordination, particularly around access and parking. Early starts and late finishes were often necessary to safely mobilise and demobilise equipment while minimising disruption to patients, staff, and the public.

Client feedback was extremely positive, advising the team did a great job, especially given the extreme weather and how long the project was. Always good to receive positive feedback!

Project Success

Across all three phases, Geocore successfully delivered a comprehensive and high-quality ground investigation programme under challenging conditions. The project demonstrates our ability to manage complex geotechnical works in live environments, utilising innovative techniques and specialist equipment to overcome site constraints.

We are proud to have supported Curtins Consulting on this project and to contribute to the continued development of the Yorkshire Hospital.