News

AGS Magazine: May 2023

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The Association of Geotechnical and Geoenvironmental Specialists is pleased to announce the May 2023 issue of their publication; AGS Magazine. To view the magazine click here.

This free, publication focuses on geotechnics, engineering geology and geoenvironmental engineering as well as the work and achievements of the AGS.

There are a number of excellent articles in this issue including;

AGS Annual Conference 2023 Review – Page 10

AGS Ground Risk Conference: Are you Managing Risks or Taking Risks? – Page 12

Geotechnical & Geoenvironmental Industry Accident Statistics 2022 – Page 18

Cyber Insurance – Page 26

Standards Update: March 2023 – Page 28

Plus much, much more!

Advertising opportunities are available within future issues of the publication. To view rates and opportunities please view our media pack by clicking HERE.

If you have a news story, article, case study or event which you’d like to tell our editorial team about please email ags@ags.org.uk. Articles should act as opinion pieces and not directly advertise a company. Please note that the publication of editorial and advertising content is subject to the discretion of the editorial board.

Article Safety

Geotechnical & Geoenvironmental Industry Accident Statistics 2022

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Within the wider construction industry, the geotechnical & geoenvironmental industry has been criticised, sometimes for good reason, for a poor safety record. It is true that this industry has not had the level of investment that mainline construction enjoys and there is internal, and client led pressure to deliver cost effective practices that can sometimes slow safety improvement and at worst negatively impact it.

To quantify the safety performance of the geotechnical & geoenvironmental industry and provide a benchmark from which to measure improvement, the Association of Geotechnical and Geoenvironmental Specialists (AGS) requested all members to volunteer accident data for the past two years as part of the annual members survey. From the members, an above statistical threshold (twenty-one) of twenty-seven organisations provided data.

How do the two industries compare?

Applying Health and Safety Executive (HSE) frequency and incident rate formulas to allow benchmarking against the HSE published Construction Statistics in Great Britain 2022, a direct industry comparison can be made.

From the HSE data, a construction workforce headcount of 2,048,611 can be identified, and a 2022 construction industry Accident Incident Rate (AIR) of 239.28, (35 fatalities + 4,185 non-fatal accidents / workforce) x 100,000 = 239.28.

In comparison the geotechnical & geoenvironmental industry (from the data provided) has an AIR of 31.28 in 2022 and 81.63 in 2021. On face value, an AIR seven times lower than the construction industry could be celebrated, however the wider picture needs to be examined before the bunting comes out.

While some activities within the geotechnical & geoenvironmental industry are high risk, such as the person plant interface during drilling activities and underground utilities, the exposure to many additional high-risk construction hazards are limited, such as working from height, confined spaces, lifting activities, etc. Therefore, a like for like comparison with construction provides little value, as the risk profiles differ vastly. Yes, drilling is a hazardous operation, but it is only one element of the geotechnical & geoenvironmental industry, and yes, the construction industry does consist of many low risk tasks, but these are surrounded by other high risk activities.

What can the data tell us?

The real value within the data can be seen when we start to look at how different size organisations compare to each other and by setting a benchmark for subsequent years incident data to be measured against.

Before looking at the incident data by organisation size, it can be assumed that small organisations have less incident reporting processes than larger organisations, as it is not needed, organisational leaders have line of sight of the incidents and can document them. Likewise, it is less likely for a small organisation to formally record hazardous events, as they are seen first-hand, and these is a much smaller group to share information with, word of mouth is sufficient.

Likewise larger organisations have tried and tested systems, with dedicated safety professionals, supported by supervisors and managers to ensure that all incidents are reported, and hazardous events recorded, with learning shared across the workforce.

The organisations which can sometimes be weaker in incident reporting, incident management and incident learning are the medium size organisations. This is dependent on the time they have been operating in this space and particularly affects small organisations which have experienced rapid growth, with little time to implement improvements in their incident management and learning.

Within organisations with smaller headcounts a single RIDDOR reportable accident can have a significant impact on their AIR. As an example, organisations within the medium contractor group, with a combined head count of 594 has recorded one accident, resulted in an AIR in 2022 of 168.35. Compare this with a single accident recorded by large organisations in the same year produces an AIR of 67.29. To produce benchmarkable AIR targets an average is required across a longer sample period, as our group size is relatively small.

The above chart details the average AIR across two years for each organisation size, which is a better demonstration of the performance of the different size organisations, together with an overall industry average. This allows comparison against similar organisational performance and future safety improvement within the industry as a whole.

When examining the small and medium contractor accident data, 39% of organisations did not record any accident, near misses or hazard events over the two-year period, highlighting a poor reporting culture and indicating a potential higher AIR than 0.00 for small and an increased rate for the medium contractors than is shown.

The Accident Frequency Rate ((AFR) total injuries / hours worked x 1,000,000)) provides a better indication of overall safety performance, as the rate is inclusive of minor injuries as well as RIDDOR reportable, which can sometimes be under reported.

Like the AIR, with 39% of small and medium contractors recording no accident data, the AFR for small and medium sized contractors could be significantly higher than detailed. This is a clear area of improvement for the industry, both in improving accident reporting and record keeping by the small and medium sized organisations and targeting these small sized organisations to develop safer working practices which will reduce harm.

The AFR across all organisations remains relatively close within 2022, ranging from 6.23 to 41.58 and an overall geotechnical & geoenvironmental industry AFR of 21.56. This provides a useful benchmark for the industry and individual organisations to measure their performance against.

Going further, to look at industry accident and incident reporting culture, the data needs to be compared with a suitable reporting frequency model. The original “accident pyramid” published by Herbert Heinrich in 1931 found that in a grouping of 330 similar accidents, one will result in serious injury (fatality, disability, lost time, medical treatment), 29 will result in minor injury (first aid), and 300 will result in no injury. Comparing industry data to an accident frequency model like this provides awareness of industry culture, as the model has been tried and tested, it is relevant. But is there a better model to use?

Looking at more recent studies there are two which go further. In 1969, Frank E. Bird conducted a follow-up study using a larger, more-randomized sample size (1,753,498 accidents). Bird found a ratio of one serious injury for every 10 minor injuries, 30 property-damage accidents, and 600 near-miss safety incidents. Due to the rigor of the study, this 1-10-30-600 ratio was accepted as an archetypal ratio in occupational health and safety.

The most recent major study of the safety ratio was undertaken by ConocoPhilips Marine in 2003. It placed the Safety Triangle within a modern occupational context and found that for every single fatality there are at least 30 lost workday cases, 300 minor injuries, 3,000 near misses (estimated), and 300,000 behaviours not consistent with proper safety procedures (estimated). Aligned to the advancements in safety delivery from 1969 up to 2003, this model is more suited to today’s standards.

From this comparison several statistical features can be observed.

Firstly, looking at the relationship between lost time injuries and fatalities it can be suggested that every 7.5 years a person working in the industry will lose their life to a workplace accident. Although not measurable over a single time period, over 37.5 years the average of 1 fatality every 7.5 years would be correct, providing there is no changes to the current working practices, and no course change between now and 2060.

The relationship between minor accident and lost time accident reporting rates statistically holds up to the ConocoPhilips Marine triangle. As these are harm accidents, it is common for these to be the most robustly reported, as following first aid administration, the first aider has a duty to report.

Looking down the triangle from minor injuries, there are clear industry weaknesses within near miss and hazard reporting. The current industry near miss reporting rate is showing an under-reporting value of 39%, highlighting a need for improvement.

Focusing on hazard reporting, 57% of the contractors stated that as an organisation they did not record hazard events and this shows, although not to a sufficient level to bring the hazard report rate in line with our accident triangle model. If the 57% reported hazardous events and at risk behaviours at the same rate as those in the industry that do, a total value of 11,924 reports would be made against a target rate of 80,000. Ignoring such an uplift, the industry hazardous event reporting rate is at a dismal 5.6% against the statistical target.

Both near miss and hazard reporting are proactive tool which can be used to prevent accidents from occurring. An improvement across both near miss and hazardous event reporting, learning and communication of the learning, would significantly reduce the amount of people harmed because of working within the geotechnical & geoenvironmental industry.

While we can not benchmark our industry accident data against the construction industry effectively, what we can do is learn from those that have walked the well-trodden path before us, in this case the drive within the construction industry to promote the importance of near miss and hazardous event learning to prevent harm.

If the organisations within our industry invest in putting in systems to capture, learn from and communicate our near miss and hazardous event learning, as an industry we can drive down the industry accident rates and improve prevention. Ultimately, we can delay, with the desire to prevent, the once in a seven and half year fatality to our workforces, colleagues, and friends.

Author Note: The sharing of accident data by AGS members has allowed the collective data to be examined to identify what, as an industry, we should be focusing on to reduce harm to our members. Please continue to share this information as it is requested each year, so we track the progress of our industry and focus our efforts within the areas which will have the most impact.

Article provided by Jon Rayner, AGS Safety Working Group Leader

Article

Loss Prevention Guidance: What You Don’t Realise You Need To Know (2022 Updates) webinar summary

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To promote the publication of the AGS Loss Prevention Guidance 2022, the AGS held a free to attend webinar on 22nd February entitled, Loss Prevention Guidance: What You Don’t Realise You Need To Know (2022 Updates). The webinar was chaired by Jo Strange (Technical Director at CGL) and included presentations from Dr Russell Jones (Commercial Director at WSP UK), Hugh Mallett (Technical Director at Buro Happold), Neil Parry (Director at Geotechnical Engineering) and Antonio Rotolo (Regional Counsel, AECOM Europe).

Russell Jones provided a talk highlighting indemnity issues, Hugh Mallett discussed reliance on third party reports and the possible liabilities associated when you use or rely upon information provided by a third party’s report. Neil Parry gave an overview of the current market conditions that affect PI premiums, and the issues which a consultant or contractor undertaking professional services should consider when procuring PI insurance. Finally, Antonio Rotolo discussed limit on liability clauses.

Thank you to Geotechnical Engineering for sponsoring the webinar.

If you missed the webinar, the replay and all speaker presentations are available for free view on the AGS website. Click HERE to view the replay.

Article

AGS Annual Conference 2023 – Overview

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The AGS Annual Conference returned to the Barbican Centre, London on 27th April 2023 with just shy of 200 delegates in attendance.

Chaired by AGS Chair, Sally Hudson and AGS Chair Elect Vivien Dent, the event featured six guest speakers covering a range of geotechnical and geoenvironmental topics, alongside the AGS Working Group Leaders who provided updates on activities and focuses from the past 12 months.

Keynote speaker, Nick Sartain (Head of Geotechnical Engineering, HS2), started the proceedings with an informative presentation outlining what is necessary for excellent communication of digital information. This was followed by Luke Deamer (Group Sustainabiltiy Manager, Keller) who provided the forum with information on the wider opportunities of sustainability to geotechnical companies. AGS Chair Elect, Vivien Dent (Technical Specialist: Green Growth and Delivery, Environment Agency) also took to the stage to give an update on Environment Agency issues, projects and guidance.

After a busy lunch of networking with industry colleagues and the 17 event sponsors, Joel Carson (CEO Executive Director, Geoprofessional Business Association), who had travelled from USA to attend the Annual Conference, presented on how the industry can learn from other people’s mistakes. This was followed by Chaido Doulala-Rigby (Chief Civil Engineer and Business Development, Tensar International) who gave a brief historic review from the origin of stabilised earth concept to today’s use of polymer geogrids in construction. Finally, guest speaker, Edd Lewis (Data Standards Lead, British Geological Survey) gave an interactive presentation on Subsurface Data Sharing and The Geospatial Commission’s Construction Playbook.

It was a great event and a brilliant opportunity for the industry to gather, network and exchange ideas.

The AGS would like to take this opportunity to thank of our speakers, sponsors and exhibitors including Soil Engineering, Geosense, Geotechnical Engineering, In Situ Site Investigation, Seequent, SOCOTEC, Groundsure, Dunelm Geotechnical & Environmental, Equipe, BAM Ritchies, Concept Consultants, AFITEXINOV UK, Envirolab, British Geological Survey, Fugro, Brimstone and 1st Line Defence.

If you missed the AGS Annual Conference 2023, you can download the majority of the speaker presentations HERE.

Article Loss Prevention

Cyber Insurance

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The sophistication, frequency and severity of cyber losses are growing. As the economy has increased its dependency upon technology, exposure to Cyber losses has surged. As hybrid working has become the new normal, and with an over reliance on an ever integrated global supply chain, the attack surface for criminal activity has expanded. These foundational changes to the way we work has further increased organisational exposure to growing systemic risks. Threat actors are using these expanded threat surfaces, and new tactics, to expand their scope to cause harm.

Ransomware events also continue to grow significantly and remain a worry for both clients and insurers alike. A recent insurer report found that ransomware events have increased dramatically in recent months, up 323% from Q1 2019.

This raises the question of how businesses are dealing with their cyber risk. Historically, businesses have chosen to manage their exposures by investing in their IT systems to defend against cyber-attacks, as well as focusing on the education and training of staff against cyber threats. Alongside this, businesses may have relied on the expectation that their existing insurance policies provided some element of cover for their cyber exposures, however regulatory changes over recent years have meant that insureds have needed to reconsider this approach.

Regulatory changes

In 2019, the Prudential Regulatory Authority (PRA) advised all UK insurers that they must have “action plans to reduce the unintended exposure that can be caused by non-affirmative cyber cover”. Lloyd’s also advised that all policies must be clear on whether coverage is provided for losses caused by a cyber event. The intention was to eliminate silent cyber exposure and with it the doubt and uncertainty that existed around coverage. As a result of this, Insurers must now explicitly exclude cyber exposure where appropriate, or affirmatively cover it.

What we have seen over the last few years is insurance policies being re-drafted to accurately describe what cyber cover (if any) they will provide. For example, where historically some protection may have been afforded under widely worded Professional Indemnity insurance policies, cyber exposure is now routinely excluded by insurers.

Due to the regulatory changes and as a result of the increasing reliance on technology to conduct business today, we have seen an uptake in the demand for standalone cyber policies. There are various products available in the market that will provide appropriately tailored and value for money cover for those firms that wish to understand, address and where appropriate transfer their specific exposures via an insurance solution.

Cyber Policies

Cyber insurance is designed to protect businesses against financial loss resulting from a range of cyber events, including extortion, data breaches, and system interruption. Cyber insurance is of growing importance because as businesses increasingly use technology to operate, the digital assets they hold are becoming more valuable and therefore more vulnerable.

Cyber policies are generally split into three categories: first-party losses; cover for incident response costs; and third-party losses. First-party and incident response cover provides an indemnity to the insured and includes cover for the cost of investigating a cyber attack, appointing forensic IT services to identify and remedy breaches, recovering lost data and restoring computer systems. Third-party cover includes cover for damages and settlements that result from the insured being blamed for causing another firm’s cyber losses and the cost of legally defending the insured against claims of a data breach.

If this area has not yet been considered, we would recommend any business assesses its cyber risk and if appropriate makes enquiries into stand-alone cyber cover. As the world becomes increasingly more reliant on the use of information technology to conduct business, it is more important now than ever to ensure that a firm’s assets, and those of its customers, are adequately protected. For further details see: Cyber Insurance – Griffiths and Armour.

Griffiths & Armour is a leading independent and privately owned UK insurance broker and risk management adviser. If you have any queries regarding cyber insurance or any questions in relation to this article, then please do not hesitate to get in touch.

Article provided by:
Sarah McNeill
Client Services Director
Griffiths & Armour Professional Risks
0151 600 2071

Griffiths & Armour is authorised and regulated by the Financial Conduct Authority.

News

AGS Magazine: March 2023

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The Association of Geotechnical and Geoenvironmental Specialists is pleased to announce the March 2023 issue of their publication; AGS Magazine. To view the magazine click here.

This free, publication focuses on geotechnics, engineering geology and geoenvironmental engineering as well as the work and achievements of the AGS.

There are a number of excellent articles in this issue including;

AGS Annual Conference 2023 – Page 8
A refresher on clean cover systems – Page 12
Net Zero – The Use of Timber Piles – Page 16
Coal Tar: Analysis and Detection – Page 20
COP27 and a ‘Way Forward’ – Page 24
Inside: Jacobs – with Solenn Le Pense, Senior Geo-digital Engineer at Jacobs – Page 26
Plus much, much more!

Advertising opportunities are available within future issues of the publication. To view rates and opportunities please view our media pack by clicking HERE.

If you have a news story, article, case study or event which you’d like to tell our editorial team about please email ags@ags.org.uk. Articles should act as opinion pieces and not directly advertise a company. Please note that the publication of editorial and advertising content is subject to the discretion of the editorial board.

Article

Inside Jacobs

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Name: Solenn Le Pense

Job title: Senior Geo-digital Engineer

Company name: Jacobs

What does the company do and what areas does it specialise in?

Jacobs is a technology-enabled global solutions provider serving several markets. We provide a full spectrum of professional services including consulting, technical, scientific and project delivery for the government and private sector. Our tunnel and ground engineering team manages ground risks and geohazards on some of the most challenging projects globally.

Where is Jacobs located?

We operate from over 40 countries and 400 offices globally. We have a network of 30+ offices throughout the UK and 22 offices across continental Europe.

How many people does the company employ?

We have more than 55,000 people globally, about a fifth of whom are working from UK and Europe. Our tunnel and ground engineering team includes around 800 employees globally.

How long have you worked at Jacobs?

I have worked at Jacobs for over two years, since March 2020

What is your career background, and what enticed you to work for Jacobs?

I started my career in academic research, with a PhD in geotechnical engineering that I obtained in France. My PhD included a fair amount of code and software development, for application to the mathematical and numerical modelling of soils. Pushed by curiosity, broad interests and a willingness to travel, I moved away from geotechnical engineering for a while, and moved to the UK to join Heriot-Watt University (Edinburgh) as a Research Associate. I was part of a research project in computational biomechanics, looking at how bone porous microstructure influences its mechanical behaviour (bone looks very much like a highly porous rock!), using finite element analysis software. I then decided to try out work outside of academia and joined a small start-up whose aim was to develop a novel airborne wind energy system that generates electricity by autonomously flying a tethered aircraft. I worked there for almost three years, and was responsible for developing modelling and analysis tools, including a flight simulator. The project was very stimulating and the team very motivated, and I did learn a lot about programming and software development (as well as aerodynamics, which was a bit outside my core area of expertise to start with!). When looking for my next job, I was then looking for a bit more stability, as well as a larger company where I could be surrounded by a lot of experienced colleagues (having found that was a limitation in a-20 people company). So, when I saw Jacobs advertising for a geo-digital engineer position, I thought it was the perfect opportunity to reconnect with my original geotechnical background, while further developing my recently developed skills and interest in programming and software development. The good reputation of Jacobs, well-known within the industry, as well as its large and experienced tunnel and ground engineering team, gave me the confidence that it would allow me to keep learning and grow as an engineer, while working on important and exciting projects.

What is your current role within Jacobs and what does a typical day entail?

I am currently a senior geo-digital engineer, part of the tunnel and ground engineering team, and am based in Glasgow. The role is very varied, and I really enjoy the diversity of tasks and projects I get to work on. Part of the role can include some traditional geotechnical engineering tasks, such as geotechnical data management and analysis, or design of geotechnical structures. Some of my core responsibilities are a bit less traditional and revolve around developing and programming design automation tools for geoscience and engineering applications. That does include a lot of programming (mainly in Python, but also C#) and software development processes. We are a team of programmers with engineering knowledge, and we can work together, or more individually depending on the size of the project. As a cross-market discipline we get to work on projects in multiple areas, such as transportation, water or energy, which makes the job varied and interesting.

What are the company’s core values?

As a company, we have four key values: we do things right, we challenge the accepted, we aim higher, and we live inclusion. We try to reflect this in our everyday work, both with clients and with each other.  Our values allow us to act as one company and unify us worldwide when interacting with our clients, employees, communities and shareholders.

Are there any projects or achievements which Jacobs are particularly proud to have been a part of?

We are very proud of the sustainable solutions we co-create with clients and other organizations. We look at ways to make a positive environmental, societal and economic difference for our people, businesses, governments and communities around the world. Some of our major programmes include the London 2012 Olympics and Paralympic Games, Thames Tideway and TEAM2100, where we have provided sustainable infrastructure and help leave a legacy for future generations, clean our water and environment, or protect our coastlines and communities. There are of course many other projects where we live our purpose of providing a smarter, more connected and more sustainable world.

How important is sustainability within the company?

Sustainability is at the core of our business, and for us it means developing long-term business resilience and success, and positively contributing toward the global economy, society and the environment. It is not simply about avoiding harm, but about maximizing impact and stakeholder value, and striving to deliver a positive, fair and inclusive future for all in partnership with our clients. Our approach to sustainability is embodied by our PlanBeyondSM programme, which is our approach to integrating sustainability throughout our operations and client solutions in alignment with the United Nations Sustainable Development Goals.

How does Jacobs support graduates and early career professionals who are entering the industry?

We invest in our graduates and early career professionals. Our Graduate Development Programme (GDP) takes our graduates through a 2-year programme of mentoring, skill building and networking to help build their careers; and professional accreditation schemes supporting staff through their chartership journeys. More widely, we implement apprenticeships to help early professionals obtain an academic qualification while working with us; drive STEAM (science, technology, engineering, arts and mathematics) engagement and leadership throughout the business, including our own Butterfly Effect programme, which is driving sustainability in decision-making for young pupils.

How has COVID-19 impacted Jacobs today? Are there any policies which were made during the pandemic that have been kept to improve employee wellbeing and productivity?

Covid-19 has been a game changer for us as an industry. For one, we’ll never go back to see the same level of travel as before as people have adjusted to hybrid working and adopted technology to collaborate and deliver work. Employee wellbeing is of course at the heart of our business decisions, including raising awareness of mental health challenges, especially in a world where perhaps we don’t see our colleagues as often and regularly as we used to. An example of the work Jacobs has done in this space is the roll out of our One Million Lives web app. The free mental health check-in tool was created to help enhance users’ understanding of their current state of mind and provide proactive strategies for personal mental health development.

Why do you feel the AGS is important to the industry?

The AGS Data Format has been around for over 30 years, has become the industry standard and, in our experience, increasingly used for every project regardless of size or complexity. Comparison with other civil engineering disciplines allows us to see the benefit that this standard format provides, as our colleagues often lack an equivalent, vendor agnostic format. AGS data helps us to work with a data-orientated approach from the beginning of our projects and fits well with the BIM environment that has become more recently familiar. The AGS fulfil an important role in continuing to manage and evolve this format to suit the everchanging needs of our industry.

What are Jacobs’ future ambitions?

As a purpose-led company, Jacobs is passionate about leaving a positive legacy for generations to come. We are channelling our technology-enabled expertise and capabilities toward benefiting people and the planet, working closely with our clients to build a more sustainable, equitable future in the context of global environmental, social, and economic challenges. Launched this year, our 2022-2024 Boldly Moving Forward strategy responds to this and is built around three key accelerators, which we see at the heart of tomorrow’ solutions: climate response, consulting and advisory, and data solutions.

Article Contaminated Land

A refresher on clean cover systems

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Image credit to Andrew Tranter, Principal Environmental Consultant at RSK

Clean cover systems are one of the most commonly applied remediation techniques deployed by developers within the UK.  They are used to reduce the risk of exposure to soils potentially harmful to health and or to reduce contaminant mobilisation by presenting a low permeability barrier to infiltration.  Consequently, they can provide both a viable and sustainable solution for mitigating risks. Yet over-familiarity is increasingly leading to poor implementation.  A refreshment and reminder on the existing guidance, the advantages, and disadvantages, as well as design considerations of cover systems, are consequently presented below.

A cover system is composed of a single or multiple layers of ‘clean’ materials which are placed above soils that are considered to be potentially harmful to a particular receptor, typically site users on a development site.  Their main purpose is usually to remove or reduce the pathway in the source-pathway-receptor conceptual model. However, one or more layers can, as already noted, have other uses, for instance,  concerning landfills, a cover or capping layer may also be used to limit surface water infiltration.

Technical guidance on the use of cover systems as a remedial technique was first included within CIRIA special publication 104, ‘Remediation Treatment for Contaminated Land Volume IV’ published in 1995, and CIRIA special publication SP124, ‘Barrier lines and cover systems for containment and control of contaminated land’ published in 1996.  However, the use of this technique for the restoration of landfills or mineral extraction sites predated any specific contaminated land guidance.  Both of these CIRIA guidance documents outlined some of the factors that should be considered when designing an engineered cover system, for example, the selection of appropriate materials to guard against the upward movement of contaminants through anthropogenic activities, burrowing animals, and capillary action.  However, there was no actual guidance given on the appropriate thickness of the cover layer to be required. This was left to the discretion of the designer , increasing the risk of an inconsistent approach between sites and geographies arising.

The British Research Establishment (BRE) subsequently published guidance document BRE465 in 2004. This sought to provide some consistency in the approach to designing cover systems.  The document divided cover systems into two distinct types; an engineered covered layer designed to completely break the pathway between the contaminated soils and receptor (as discussed in the CIRIA guidance), and a simple cover layer that reduces the exposure to a receptor.  The detail of this BRE guidance was, however, only to focus its content on simple cover system design.

A key question considered within this BRE guidance was to be the level of intermixing between soil layers that could be considered to arise within a domestic setting. The research was to state that disturbance from anthropogenic activities (digging) and intermixing due to natural processes, such as burrowing animals, earthworm activity, and plant roots, was unlikely to exceed 600mm.

Based on these findings, this guidance contained a method for calculating the thickness of the cover, which used 600mm to be the default mixing zone.   For a given contaminant of concern (COC), the BRE equation determined how much cover would be required to reduce the concentrations to a pre-determined target concentration/assessment criterion.  As a conservative approach, the equation considered that all mixing would occur uniformly across the whole of the mixing zone, but in reality, disturbance (impacted soils being brought to the surface) was likely to be localised.   Finally, the maximum depth of the cover was set at 600mm, but this could be altered if there was reasonable justification.

An Excel spreadsheet was provided with the BRE guidance and a simple check graph enabled the user to determine whether a simple cover system was appropriate.  If the concentration of the COC was too high, then this would be highlighted by the graph.  Advice against the deployment of a simple cover system was also made under conditions where:

  • Non-threshold contaminants (i.e. those that may pose a risk at any concentration, such as asbestos) were present,
  • other contaminant pathways were present, such as the inhalation of vapours/gas, direct contact with rising groundwater, etc.,
  • if there was a risk to groundwater and the need to reduce leachability,
  • where sloping ground was present i.e. where a consistent thickness of cover could not be maintained, and
  • where in areas deeper excavations were required for ponds, tree planting, fencing, etc.

BRE465 remains to be a commonly applied reference.  The NHBC published a technical extra (issue 8) in 2012 on the ‘verification of clean cover system-testing of subsoil and topsoil’.  This document has clearly stated that the topsoil should meet British Standard 3882:2007 and has provided details of how many plots on a residential development should be validated.  The current NHBC technical standards (2022) Chapter 10.2 (Drives, Paths and Landscapes) further positions that:

  • Works should be carried out following a formal remediation statement,
  • Topsoil and subsoil should be of a quality that does not pose a hazard to users,
  • Old foundations, concrete bases and similar obstructions should be removed from 450mm of finished ground level,
  • Appropriate action should be undertaken to restore the physical conditions and drainage characteristics of topsoil and subsoil that has been compacted during construction,
  • A minimum thickness of 100mm topsoil is required.

A key message is that even if the NHBC is not involved with a development, it is now considered as ‘ordinary care’, as their guidance is followed when designing and validating a cover system as a matter of normal practice.

Of further note then with familiarity, it has almost become standard to apply a 600mm clean cover system. Sometimes, but not always, this is underlain by a marker layer in private gardens.   The presence or absence of a marker layer should always be clearly and explicitly described in the remedial strategy. Such reasoning is too often absent or simply inferred.  Next in regards to 600mm this may indeed be adequate to reduce the risk to an acceptable level, however, there is again often little or no justification to the design.   Indeed this depth is based on the mixing zone from the BRE guidance, but the purpose of the guidance was not to set a definitive depth for a cover system.  Assessment criteria derived using the Environment Agency’s contaminated land exposure assessment (CLEA) model takes into account exposure to site users within the top 1 metre of soil. Also, if a landscaped area is planted with trees then the roots will extend beyond a metre depth.  The depth of the cover system should always be based on its specific setting.    In summary, the thickness of a cover layer should again always be clearly and implicitly described in the remedial strategy. Such reasoning is once again too often absent.

Overall,  the advantages of specifying a clean cover system are that it can negate the requirement for the removal of a contamination source; is generally straightforward for a groundworker to implement, and is widely accepted by a Local Authority.  The disadvantages are that to often to little consideration is given to the appropriate design of cover systems. Furthermore; where ground levels cannot be raised, the soils is excavated and removed to accommodate the cover system. The removed soil can either be disposed of off site or reused in accordance with a Materials Management Plan (MMP). Other risk assessment or remedial measures may be able to reduce the quantity of soil requiring replacement and /or disposal. Indeed, the need on occasion of some cover systems can be avoided if a detailed risk assessment is carried out.

In conclusion, the use of a cover system can be a very reasonable and cost-effective remedial solution to use, as long as they are documented, designed then implemented with thought and critical thinking.  However, the technique is so widely used that with over-familiarity it is perhaps sometimes abused.  It may be that as consultants contractors and developers we should take the opportunity to reflect and remind ourselves that we must ensure that a consistent and critical approach is applied. Lastly, let’s never forget to validate!

The National Contaminated Land Officers Group (NCLOG) cover systems subgroup are currently working on a new guidance document, so please keep a look out.

Table 1. Cover systems at a glance

What is a cover system?
Cover systems fall into two categories: firstly, a simple cover layer is typically composed of  one or two layers (topsoil/subsoil) of ‘clean’ material that reduces the exposure to potentially harmful substance(s) in the strata it is placed over.

Secondly, an engineered cover system comprises one or multiple layers which prevent contact within the underlying soils.  Each layer may be designed for a specific purpose such as reducing infiltration, capillary break, no-dig later, etc.
Design considerations (examples)
1)     Purpose of the cover system (simple or engineered)
2)     Topography of the site
3)     Landscaping details
4)     Suitability of the cover soils
5)     Drainage/groundwater
6)     Depth of cover
7)     Sustainability (removal of soils for off-site disposal)

Article provided by Andrew Tranter, Principal Environmental Consultant at RSK

Article

AGS Photography Competition 2023 – photos for AGS stands and extended deadline

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The AGS is holding a new photography competition for 2023!

We’re on the lookout for your most creative images which are reflective of the geotechnical and geoenvironmental industry.

The winning photos may be used to update the AGS stands, which are used at events and conferences, and across our marketing materials.

If you’re a budding photographer or have a great engineering image which you’d like to enter, then we’d like to see it!

Entry into the competition is free and the winner of the competition will win a food hamper basket from luxury retailer, Fortnum and Mason, worth over £75. Three runners up will each win a bottle of Champagne.

There are no restrictions on the photography equipment used, so feel free to use a phone, computer, tablet or a traditional hand-held camera to capture your image as long as the below criteria are met.

All entries will be reviewed by select members of the AGS, who will decide on a shortlist and a potential winner. Full details will be announced in the November issue.

IMAGE REQUIREMENTS

The AGS are looking for high resolution JPEG images (300 DPI / over 1MB image file size) of a geotechnical and geoenvironmental nature. Images can include project imagery, laboratory testing, collaborative working and more. Photographs featuring any on-site operatives should showcase health and safety procedures in place, if appropriate. Images should be no smaller than 4200 x 3400 pixels.

HOW TO ENTER
• Please email your image with;

  • A short description of what it showcases and where it was taken (up to 50 words)
  • Image credit information (if applicable)
  • Your full name
  • Company name
  • Postal address

to ags@ags.org.uk with the subject ‘AGS Magazine: Photography Competition 2023’ in the email.

  • There is no limit to the number of images you enter.
  • The deadline for entries has been extended to 25th August 2023.
  • Entry into the competition is free.

TERMS AND CONDITIONS
• Applicants must be aged 18 or over.
• All images must be high resolution and 300 DPI (dots per inch) / over 1MB image file size.
• Applicants must be based in the UK.
• The photographer must have full copyright of all entered images and appropriate permissions from all involved parties, for all images submitted.
• All images entered may be reproduced by the AGS and used in future AGS event and marketing literature without prior notice. This may include usage across the AGS’ social media channels, inclusion in the AGS Magazine, event programmes and on the AGS website. Please note that all images used will be credited.

 

 

Article Sustainability

COP27 and a ‘Way Forward’

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Between 6-20 November 2022, the COP27 (‘27th Conference of Parties’) conference was held in Sharm El Sheikh, Egypt. This built on discussions and decisions made at the COP26 conference in Glasgow in 2021.

You may ask why is this relevant to the AGS?  Simply put, the effects of global warming and climate change affect everyone and every business sector. The UK Government set a clear mandate for the UK to achieve zero carbon emissions by 2050, and for this to be achieved,  all businesses need to be aware of Government policy and start the process of baselining and carbon control/ reduction. The direction of Government policy is likely to be highly influenced by the outcomes and agreements made at the COP conferences.

A summary of the headlines from COP27 is listed below. Relevant items to the geo-industry are the ‘Early Warning System’, ‘Clean technology’ and ‘Adaptation’.

  • Loss and damage fund– Governments agreed to establish new funding arrangements, as well as a dedicated fund, to assist developing countries in responding to loss and damage.
  • Brazil is back– Brazil’s president (the elect) Luiz Inácio Lula da Silva announced that “Brazil is back”. He said: “There is no climate security for the world without a protected Amazon. We will spare no efforts to have zero deforestation and the degradation of our biomes by 2030.”
  • Emission commitments– The US also announced plans to cut methane emissions, leading to an 87% reduction by 2030, compared to 2005 levels. Mexico has upped its commitment to cut carbon emissions from 22% to 35% by 2030.
  • Indonesia Just Energy Transition Partnership–The partnership will mobilise $20bn over the next three to five years to accelerate a just energy transition.
  • Early Warning System– An action plan for the Early Warning for All initiative was launched at COP27, which will be able to give early warnings against increasingly extreme and dangerous weather to everyone on the planet within five years.
  • Clean technology– Governments representing over half of global GDP set out a 12-month action plan to help make clean technologies cheaper and more accessible everywhere, as part of the ‘Breakthrough Agenda’.
  • More focus on adaptation – New pledges, totalling more than $230m, were made to an Adaptation Fund at COP27. The Global Shield Financing Facility was launched to provide funding to countries suffering climate disasters.
  • Forest and Climate Leaders’ Partnership launched– This will hold annual meetings with government representatives on progress to halt forest loss and land degradation by 2030

In a round up by Sarah Mukherjee, CEO of IEMA, who attended the COP27, she commented on COP27;

  • “Without the skills, without the training, and without education, there will be no green economy. These skills are not just for the office workers and the latte-drinking classes, but they are for technicians, for engineers, for people who are doing first and secondary jobs within the economy and are absolutely vital if we are to get where we need to go.”
  • $100 B per year required from developed countries for meaningful mitigation actions
  • The 1.5oC limit on rising global temperatures is still achievable …just

Therefore, it appears that provided the population is educated, trained and enabled to support a ‘green economy’, which will also require adaptation and use of clean technology, the target limit on global warming is still ‘just about’ possible, but the happenings during the decade to 2030 will be crucial. Everyone and every business can be part of achieving current targets.

The AGS is looking at creating a sustainability working group which will act across all the existing working groups to coordinate ideas, tools,  innovations and guidance to support the AGS members and the geo-industry in navigating the route to carbon net zero and support minimising climate change.

Article provided by Jo Strange, Technical Director, CGL

Article Laboratories

Coal Tar: Analysis and Detection

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The analysis of and detection of coal tar has seen a significant increase in the last few years. This is linked, primarily, with an increased focus on thorough waste classification and some long running nationwide initiatives such as the Streetworks Project. It encompasses all the regional water companies and activities in line with the Regulatory Position Statement RPS211 relating to the excavated waste from utilities installation and repair, the withdrawal of which was delayed until April 2023 due to the scale of works underway and still requiring of completion.

One of the challenges facing laboratories is the lack of standardization in the specification of requirements from the clients and also the analysis itself. As an area not fully understood in terms of hazardous classification, it became beholden on the labs to put forward a range of approaches that would encapsulate the variety of client specifications while also providing what was hoped would be sufficient levels of detail to allow for the onward use of data for a range of purposes.

A recent review through the AGS Laboratories Working Group revealed a range of techniques, some common themes and a potentially confusing landscape for the industry to navigate in order to secure a fit for purpose and cost effective solution.

The two primary sources of information which influence the testing requirements, other than the labs individual clients are the EA WM3 (1st Edition v1.2) Technical Guidance and the ADEPT Guide to Managing Reclaimed Asphalt (Version 2019 revision 1).

From section 3.2 of WM3, we have the following based on the knowledge that coal tar is present:

  • Coal tar levels over 0.1% result in a hazardous classification to HP7,
  • The total must be inclusive of all compounds, polycyclic aromatic hydrocarbons (PAH) concentration alone is not sufficient,
  • If the concentration of Benzo(a)pyrene (B(a)P) is less than 0.005% of the coal tar then HP7 does not apply.

Looking specifically to Asphalt waste already classified  under 17 03 01* or 17 03 02 (bituminous mixtures that do/don’t contain coal tar respectively) then we also have to consider:

  • If B(a)P is greater or equal to 50mg/kg in the Black top alone then the amount of coal tar should be considered to be sufficient (0.1%or more) to be considered hazardous and coded 17 03 01*.

The ADEPT guidance provides more specific focus on the managing of reclaimed asphalt and provides information in to the classification of waste. It reiterates and references WM3 and the 0.1% threshold for coal tar and also the use of the 50mg/kg level for measuring B(a)P should the total coal tar concentration not be available for measurement.

What the ADEPT guidance then gives, is a clear and defined protocol for sampling, sample preparation, sample volumes and data review with also indication of analytical requirements and basic principles.

The document gives details and refences to specific British Standards for the sampling and preparation of road plannings and road cores (BS 932 and BS 12697), and then recommends the following testing;

  • PAH analysis in the laboratory by gas chromatography mass spectrometry (GCMS) for the USEPA16 suite of PAHs, though only B(a)P may be necessary. It is worth noting here that labs will test for the full suite in a single process so requesting B(a)P only will usually give no cost or speed benefit. Should further characterisation for landfill disposal be required then the USEPA17 suite inclusive of coronene should be used,
  • Screening methods such as PAK marker sprays or Acrylic White sprays can be used but validated by the use of frequent ‘full’ analysis,
  • Specifies the use of Monohydric Phenol (Phenol Index) testing, with a potential requirement to speciate the individual compounds (Phenol, Cresols and Xylenols) should the levels be sufficiently high.

In terms of data review the 3 potential outcomes are

1.Classed as Inert for the purposes of the Quality Protocol for Aggregates from Inert Waste if:

a. The guidance of sample numbers has been observed,
b. All the B(Aa)P results are below 25mg/kg,
c. There are ≥3 results.

2. Classed as Hazardous and treated accordingly is:

a. All the B(a)P results are above 50mg/kg

Note: If there are limited results and close to the threshold then further investigation is      required

3. Full statistical analysis required to make assessment if:

a. Some or all results are above 25mg/kg and below 50mg/kg

The incorporation of the Waste Acceptance Criteria (WAC) testing for characterization and landfill disposal is a good example of where labs adapt to meet the broader requirements of the customer. From the recent AGS LWG study, we can see a number of consistent elements:

    • Quantification of PAH compounds including B(a)P,
    • ‘Total’ extractable material/coal tar, usually by Dichloromethane (DCM) extraction and quantification either gravimetrically or by GCMS
    • ‘Forensic’ identification of coal tar

There is little to no consistency as to the how, but the principles all involve the selective identification of 1 or more marker compounds (Benzothiophene was common but arrange of other phenols, heterocyclics and aromatics were used) by GCMS

And then also often included in the suite we can see:

  • A range of more traditional TPH tests, from a straightforward C10 – C40 extractable Hydrocarbons to a more thorough TPHCWG range from C5-C44 including Aliphatic and Aromatic breakdown,
  • A Chromatographic interpretation of the hydrocarbon source
    • Usually taken from the TPH analysis, done either as a general identification against a library of standard chromatograms to identify exactly what fuel source is present, presumably should it not be Coal Tar. A specific determination of whether the hydrocarbon source can be identified as either diesel or weathered diesel. While neither of these are specifically relevant to Coal Tar, as part of the Classification process within WM3 when considering hydrocarbon contamination then should coal tar not be the issue, varying caveats can be applied to the hazardous threshold should the contamination be of a specific type and the laboratory identification of diesel as a source is one the most prevalently used.
  • Phenolics
    • Either as a simple Monohydric Phenol (compounds containing one hydroxyl group) of a speciated output using HPLC or GCMS to identify specifically the Phenol, Cresol and Xylenol content amongst a range of other phenolic compounds.

The running of additional testing may seem extraneous based on the specific context of your project at that stage, but consideration of any subsequent stages may give rise to a more comprehensive suite. The relative costs of laboratory testing compared to the associated site costs in holding/transporting/disposing of waste materials are low, so a comprehensive approach may present a more cost effective solution.

It is also worth revisiting the question you are trying to answer, as the specific identification of coal tar may be of secondary importance to the quantified PAH, specifically the B(a)P results, in terms of onward management.

As with any project involving lab work, the overarching recommendation would always be to consult with your lab at the outset and throughout to discuss options and define a project specific set of requirements rather than looking for a default or ‘standard’ solution, especially in an area like waste and waste classification where standard solutions are a thing we can still only imagine.

References:

  • Guidance on the classification and assessment of waste (1st Edition v1.2.GB) Technical Guidance WM3 (October 2021)
  • ADEPT Guide to Managing Reclaimed Asphalt Version 2019 Revision 1 (August 2019)

Article provided by Will Fardon (Technical Director, Chemtech Environmental Limited) on behalf of the AGS Laboratories Working Group

Article Geotechnical Sustainability

Net Zero – The Use of Timber Piles

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Introduction

As the construction industry works towards a ‘Net Carbon Zero’ future, we are asked to take a hard look at current practices to find areas where the carbon cost associated with our built environment can be reduced. The cement industry is widely recognised as being one of the main producers of carbon dioxide emissions, accounting for around 7% of global emissions. Low carbon and carbon neutral concrete products are already entering the market, but the use of timber as an alternative to concrete piles provides an opportunity to use a sustainable foundation material. This brief article considers the benefits, limitations and suitability of using timber piles in the UK.

In 2009 a technical paper by Reynolds and Bates was published in Ground Engineering magazine, titled “The Potential for Timber Piling in the UK”. It explored the current global locations and circumstances in which timber piles are used and discussed the potential for UK locations with comparable ground conditions where their use could be considered. The article states that timber piles are currently widely used in the Netherlands, the United States, New Zealand, Canada and Australia, and concludes that timber piles are “an entirely viable, low cost and sustainable alternative to steel and concrete, with the potential to be used for many projects”. A notable example of timber pile use given in the article is the Cargo Terminal at John F. Kennedy Airport in the USA. BRE Digest 479 (Timber Piles and Foundations) cites a number of historic examples where timber piles have been used, including Old London Bridge in the UK, the Royal Palace in Amsterdam and the Pont Notredame bridge in Paris.

Timber Pile Characteristics

A timber pile is essentially the trunk of a tree, stripped of branches and bark. They are currently used in the UK in maritime construction, such as groynes, piers, jetties and for sea defences, where timber is favoured due to its ease of handling in overwater environments, its ability to absorb impacts and low cost.

Since timber is a renewable material it has a significantly lower carbon cost associated with its production and use than its concrete and steel counterparts. The monetary costs to produce and transport timber piles are lower than those of concrete and steel (as described in Reynolds and Bates, 2009). The placement of timber in the ground is a form of carbon sequestration, which plays an important part in ensuring the overall Net Zero compliance of a project.

One of the main drawbacks to using timber is that it is biodegradable. Decay occurs fastest when the timber is exposed to the air, which allows fungal decay and rot to occur. As such, a typical life span for timber placed in an unsaturated environment is c. 25 years.

Timber placed below groundwater level, in a saturated, anoxic environment, will decay at a much slower rate and can have a design life of up to 100 years depending on the timber species used. The piles can be chemically treated to provide additional resistance to biodegradation, however, the chemicals used may have the potential to introduce contamination into the ground.

To minimise degradation, the top of the pile that extends above the water table (i.e. not in saturated ground) is typically formed of concrete. This can be a pre-cast concrete section connected to the timber or can comprise a concrete pile cap spanning several timber piles. Pre-boring the pile locations and setting the timber pile in concrete or grout can also be used to slow degradation, however this will increase the amount of concrete used and the arisings that require disposal.

Although timber, as a pile, will have a lower compressive strength compared to concrete or steel piles, it is often the case that the bearing capacity of the pile is governed by the properties of the surrounding soil rather than the strength of the pile itself. On this basis the use of timber piles may be equally suitable to that of concrete in certain settings.

Pile length is another design consideration that may impact the suitability of using timber piles. As timber piles are typically difficult to splice, the maximum pile length is restricted by the height to which the tree can grow, which is also dependant on the species. Conversely, timber piles can easily be cut down to size as needed and the off cuts are biodegradable.

Pile Construction and Suitable Locations

Installation of timber piles is predominantly carried out using driven techniques. The success of this technique will depend on the ground conditions, since the presence of dense layers, hard bands or variable strata could result in the refusal of the piles at unplanned depths. Driving through harder bands may be achieved with the inclusion of a driving shoe at the toe of the pile, therefore a good understanding of the ground conditions present is key to ensuring the successful installation of timber piles.

Ground conditions most amenable to the installation of driven timber piles comprise soft deposits such as soft clay or peat, over a denser material such as gravel or rock, with a high water table. Reynolds and Bates identify such ground conditions to exist in numerous estuarine and river valley locations around the UK, including the Severn estuary, the Fens in east Anglia and the marshes of Dartmouth.

The seasonal variation of groundwater levels at a site needs to be well understood if the development is to consider using timber piles, as the degradation, and consequently the design life, of a timber pile is primarily governed by whether the ground is saturated or not. This places a greater importance on groundwater monitoring and modelling to understand the existing groundwater regime as well as the impact that climate change will have on groundwater levels through the design life of a project. Understanding the groundwater regime of a site is already a key part of geotechnical design, and a requirement of Eurocodes. As such, any additional data gathering at ground investigation stage of a project may not extend significantly beyond the typical geotechnical needs of a project.

Conclusion

Ground conditions exist in the UK that may be amenable to the use of timber piles. As with any geotechnical design, the collection of relevant information at ground investigation stage is crucial, but wouldn’t necessarily require any particular measures beyond what would be expected in order to satisfy current standards. The use of timber for on-shore piling is not an impossible or unreasonable solution to reducing the carbon cost of construction and may, in due course, be driven by necessity to address the climate crisis.

References
1. https://www.geplus.co.uk/technical-paper/technical-paper-the-potential-for-timber-piling-in-the-uk-01-01-2009/

Article provided by Katharine Barker, Associate, Campbell Reith