Archives: News

Latest news from the Harrison Group

Harrison Contributes to Renovation of King’s College, Cambridge


December 13, 2021

Harrison Contributes to Renovation of King’s College, Cambridge

King’s College Chapel is a Grade 1 listed collegiate chapel of the University of Cambridge, built in the 16th century and located in the heart of the historic city centre. Currently, repair work to the roof is programmed to be undertaken; and this is to be done whilst allowing the chapel to continue functioning as an active place of worship, as a home to King’s College Choir and to also accommodate the steady daily stream of visitors to the building.

Harrison Group was contracted to carry out a ground investigation to assess the load bearing characteristics of the ground that would support an extensive scaffold structure, to ensure that it would be safe and secure.

In addition to this, an investigation was also carried out to establish groundwater levels underlying the chapel itself, providing information relating to planned conservation activities.

Read more about how Harrison Group adapted their work to allow the chapel to continue functioning as an active place of worship, as a home to King’s College Choir and to also accommodate the steady daily stream of visitors to the building.

Restoration of Norwich Castle Keep


July 23, 2021

Restoration of Norwich Castle Keep

Harrison Group has been involved in an ambitious project to restore Norwich Castle Keep back to the original layout that existed in the 12th century.

To read more about the scope of work, challenges faced due to restricted access and the potential presence of archaeological artefacts Click Here.

Elecric-powered, low-headroom cable percussive rig

Harrison Contributes to Major Offshore Windfarm


July 21, 2021

Harrison Contributes to Major Offshore Windfarm

Taking on the challenge of mobilising to a remote Norfolk beach location to carry out investigation for major offshore windfarm, Harrison Group used a landing craft to transport all the plant and equipment to site by sea directly from the Port of Lowestoft.

To find out more Click Here

Drilling compound

Norfolk Constructing Excellence Awards 2021 for Harrison Group


April 26, 2021

Norfolk Constructing Excellence Awards 2021 for Harrison Group

After a year of absence due to coronavirus restrictions in 2020, the Norfolk Constructing Excellence Club (NCEC) Awards ceremony went ahead this year on 20th April as an online event.

Constructing Excellence of which the NCEC is a member club, through networking events, aims to bring together industry professionals from member organisations in a relaxed, forward-thinking environment, to share ideas and best practice with opportunities for continued professional development.

The NCEC has over 70 members, ranging from SMEs to national companies, and representing all parts of the construction supply chain including clients, consultants, designers, engineers, contractors and suppliers.

Members are encouraged to take part in the yearly awards event, where advancement and success across a range of categories are recognised, reflecting current best-working practices. Sustainability, Value, Collaboration and Health & Safety are just some of the categories under the spotlight.

Harrison Group is very pleased to have been awarded 1st place in the Innovation category, for its specific contribution to progressing the quality of 3D ground modelling of borehole information. This work has resulted in much-improved visualisation and understanding of subsurface geotechnical and geoenvironmental trends, leading to high quality and versatile 3D ground model production, which can reduce risk and lead to potential project cost-savings. In addition to this, Harrison Group was also awarded 3rd place overall.

Harrison Contributes to the Big Borehole Dig


March 16, 2021

Harrison Contributes to the Big Borehole Dig

With increasing usage of digital data in recent times, particularly for interpretation and analysis of ground investigations, there have been associated changes to the methods by which we work. Despite the advantages of this, difficulties can arise when data is not available in a standard format. This can be due to the use of differing software packages and the related compatibility issues that arise when transference of data is required.

Taking this into account, the British Geological Survey (BGS) has launched a major initiative, called the ‘Big Borehole Dig’, to convert around one million existing borehole records currently held on its database. The aim is to translate the information into the Association of Geotechnical and Geoenvironmental Specialists (AGS) digital data format, the accepted industry standard.

There will be benefits arising from this process. Once standardised, it will be possible to pull the information directly into current site investigation digital software, improve conceptual ground models and provide an additional resource for academic purposes. This will, amongst other things, give savings of time and costs in construction projects, by having access to an enhanced and transferable data set.

With over 40 years in the industry, Harrison Group is well placed to appreciate the value if this initiative. Head of the Data Management department, Conrad Stewart and his team, are actively involved in helping to process the BGS data. While contributing to the bigger picture, Harrison Group is already finding the results very useful for its own purposes, as it has been integrating the BGS borehole information with data from current site investigations.

The scale of the Big Borehole Dig is vast. The more contributors there are to this project, the sooner it will be completed to the benefit of all. For more details and how to get involved, go to the BGS website:

If you would like to follow the progress made by Conrad and his team, he gives updates via his LinkedIn account:

Also, if you would like to know more about how our advanced data management systems improve the quality of geotechnical and geoenvironmental analysis, please click on this link:-

Current digitised borehole records of an area of Norwich – Harrison logo shows Harrison Group head-office location

Borehole sections after modelling

BGS historical borehole log – received in PDF format

COVID-19 Compliant Investigation at ExCeL Exhibition Centre


January 29, 2021

COVID-19 Compliant Investigation at ExCeL Exhibition Centre

Harrison Group were contracted by Campbell Reith Hill LLP to undertake a site investigation in the eastern car park of the ExCeL Exhibition Centre, London, in order to provide information on ground conditions to inform foundation design, contamination assessments, and any remedial measurements required for the construction of a two-storey, 40,000m2 extension.


At the time of the investigation, COVID-19 restrictions were in place and the ExCeL Centre was host to a Nightingale Hospital. As a result of this the site was set up by Harrison Group and ran to facilitate social-distancing, with measures such as additional welfare facilities put in place.


Read full case study here.

Site plan showing intrusive investigation positions

Typical machine-excavated trial pit

COVID-19 compliant welfare facilities for site staff

UKAS Accreditation by Remote Surveillance


December 30, 2020

UKAS Accreditation by Remote Surveillance

Under strict COVID-19 restrictions, Harrison Group has recently undertaken the annual UKAS Accreditation Remote Surveillance Audit for its independent soil testing laboratory. This was carried out with the aid of Teams, OneDrive and WeTransfer and is a first for the company.


Over a period of a month, 15 videos of between five to ten minutes duration were prepared of the procedures.


The feedback received was excellent. Zero non-conformances for testing were recorded and there were no recommendations made for improvement.


Whilst a major effort was needed to produce the video material, it is now also a useful resource for the company, to be used for future training and accreditation purposes.


Well done to Henry Chapman, Matthew Wilson and the laboratory technicians for their hard work in gaining this latest accreditation for the laboratory, which is another example of how Harrison Group is adapting in the current climate to maintain its high standards.



Perfect Delivery Achieved by Harrison Group


December 21, 2020

Perfect Delivery Achieved by Harrison Group

Harrison Group has been awarded ‘Perfect Delivery’ by Morgan Sindall for the work carried out  at the West Suffolk Operational Hub. Delivered through the Suffolk County Council framework, this is a project that has centralised, improved and transformed waste management across the region. The project was delivered on time, in budget, 100% Safe and scored 9/10 for customer satisfaction.


90% of Morgan Sindall Group’s project spend was with local SME’s of which Harrison Group was a part.


The work was carried out in a number of phases by Harrison, between 2017 – 2019 and involved geotechnical site investigation, in-situ testing and consulting. The project was managed from our Cambridge office with Jamie Austin at the helm for the duration of the works.

Light Weight Deflectometer Capability for Harrison Group


December 15, 2020

Light Weight Deflectometer Capability for Harrison Group

The Light Weight Deflectometer (LWD) apparatus is used to provide in-situ measurement of the foundation surface modulus (E) of the subgrade for use in pavement design. It is also useful in compaction control for bound and unbound base layers and sub-bases.


The foundation surface modulus is a measurement of the stiffness of the layer upon which the test is undertaken in terms of transient deflection caused by the application of a dynamic stress through a circular plate. The test method is set out in BS 1924-2:2018, 9.2 “Hydraulically bound and stabilised materials for civil engineering purposes, Part 2, Sample preparation and testing of materials during and after treatment” but is also referenced in ASTM Standard E2583-07: 2011 “Standard test method for measuring deflections with a light weight deflectometer (LWD).”


The standard test equipment comprises a 300mm diameter plate which is dynamically loaded through a buffer system to produce a load pulse of 15 ms to 30 ms duration using a 10kg weight falling from a variable height (generally less than 1m) to impart a target stress in the order of 100kN/m2 (100+/-5 kN/m2). The actual stress imparted is measured by a load cell within the equipment and the resulting deflection is measured by a geophone in the centre of the plate to a precision of +/-2µm.


Read more

Site set-up

LWD apparatus

Information. BSI – Latest Updates: 29.06.2020


June 29, 2020

Information. BSI – Latest Updates: 29.06.2020

BS 5930 Code of Practice for Ground Investigations has been amended. BS 5930:2015 +A1:2020 has just been published. The amendment contains the following main changes from BS 5930:2015.


  1. Update to ground investigation and geotechnical design in accordance with the latest BS EN ISO test standards meaning that different methods of work should not have to be adopted when operating in different countries.
  2. Update to description of soils and rocks in accordance with BS EN ISO 14688 (Book 3D7):
        • Geotechnical investigation and testing – identification and class of soil Pt 1. Identification and description and
        • Geotechnical investigation and testing – identification and class of soil Pt 2. Principles for a classification
  3. and 14689 standards (Book 3D7):
        • Geotechnical investigation and testing – identification and class of rock (ISO 14689-2017)
  4. Update to accommodate changes in BS EN ISO 17892 standards and related BS 1377 parts; more specifically:-.
        • Geotechnical investigation and testing- laboratory testing of soil Pt.1 Determination of water content
        • BS EN ISO 17892-2.2014 Geotechnical investigation and testing- Laboratory testing of soil Pt.2 Determination of bulk density
        • Geotechnical investigation and testing. Laboratory testing of soil. Determination of particle density
        • Geotechnical investigation and testing. Laboratory testing of soil. Determination of particle size distribution
        • Geotechnical investigation and testing. Laboratory testing of soil Incremental loading oedometer test
        • Geotechnical investigation and testing. Laboratory testing of soil. Pt 6 Fall cone test
        • Geotechnical investigation and testing. Lab testing of soil. Pt 7 Unconfined compression test
        • Geotechnical investigation & Lab Test of soil Part 8. Unconsolidated undrained triaxial test


Relating this information to BS 5930:2015 +A1:2020, the changes can be referenced as follows:


      • Chapter Topic Pages
        5.3 New communication- Asbestos 12
        10 3 dimensional ground model reference 18
        14.2 Topographical mapping, imagery and 3D 24/25
        33.4.5 Anthropogenic ground (table 18) 112/113
        33.5 Name, age and type of geological unit 116
        36.2 Description of rock materials (table 25) 121
        36.2.6 Rock name (commentary) 125 Weathering classification Figure 9 128/129
        44 Field Density, SRDs and Electrical test 148/149
        57.2 Screening of Laboratory Samples containing hazardous samples. Safe to test information 191
        61 Laboratory tests- General  (tables list) 194
        Table 37 Common Laboratory Tests for Soils (table) references 195-207
        Sect 10, 62 Reports, Interpretation, Notes and references 212
        63.2.3 Photography, imagery, format (samples etc.) 219
        Annex G 1. Integrated field investigations (note) 261

In addition to this:

BS EN ISO 21365:2020 Soil Quality. Conceptual site models for potentially contaminated sites has been published and is available from the BSI bookshop.

1 Scope
This document provides guidance on developing and using conceptual site models (CSMs) through the various phases of investigation, remediation (if required), and any subsequent construction or engineering works.
It describes what CSMs are, what they are used for and what their constituents are. It stresses the need for an iterative and dynamic approach to CSM development.
This document is intended to be used by all those involved in developing CSMs and by those who rely on using them such as regulators, landowners, developers, and the public (and other relevant parties). Ideally, this includes representatives from all phases of the investigative and remedial processes, for example, preliminary assessment, detailed investigation, baseline human health and environmental risk assessments, and feasibility study, and, any subsequent construction or engineering work.

NOTE 1 This document is applicable whenever the presence of “potentially harmful” or “hazardous” substances are present irrespective of whether they are naturally occurring or present due to human activity (i.e. are “contaminants”).

NOTE 2 Although most of the principles described for developing CSMs in this document can apply to other domains, such as groundwater resources management, the present document is specifically written for the management of potentially contaminated sites or known contaminated sites.