AGS Magazine - June / July 2020

June / July 2020

IS IT TIME FOR A CHANGE? The AGS Geotechnical Working Group respond to an article discussing the value of the Standard Penetration Test

WORKING AT HEIGHT AND TRIAL PITTING

INTRODUCING OUR LATEST WORKING GROUP

AGS AWARD WINNERS FOR 2020

Steve Everton of Jacobs looks at possible safety measures for Trial Pitting

The AGS Instrumentation & Monitoring Working Group is revealed

Annoucing the full list of winners of the AGS Awards for 2020

Chair’s Foreword It has been a busy time for many members since the May issue and many colleagues have reported the increased pressure on their time attending Team or Zoom or WebEx meetings. I have to be honest and admit that I am still getting used to the nuances of each system but it is clearly the way forward. Remote meetings and the increase in video conferencing and events is here to stay and makes so much more sense by reducing travel time and our carbon footprint.

building projects will also assure a steady workload for many members. The housing market also appears to be improving and is projected to steadily increase to pre-COVID levels early 2021.

The adaptation of our members and their staff to COVID restrictions has been a credit to our sector and reflects the resilience of our members. We have seen dramatic changes in behaviour, innovation from a number of our members and the importance of data is becoming With this in mind, the AGS has better recognised but still a decided not to hold any scheduled lot of AGS work to do here. For face to face meetings or events many, COVID compliance is for 2020 but I am excited to report uncomfortable on many levels that we will be starting Webinars but overall we are coping well and and on-line events from July 2020. meeting the challenge head on.

Look out for announcements will I reported previously that we be e-mailed and posted on social had lobbied UKAS to extend media within the next couple of weeks. We have also set up Teams or improve their assessment practice and I am pleased to report groups for all of our Working Parties and hope that this will lead that this succeeded in UKAS reporting that all assessments to a more efficient and effective including new accreditations way of collaborating even when would be completed remotely face to face meetings return. and principally by video. This Most organisations have now has enabled our laboratories to brought back their staff from maintain accreditations and also furlough but it is disappointing, in some cases to add to their but not surprising, that some portfolio. organisations have started We have also started to rekindle redundancy consultations key AGS initiatives such reflecting the uncertainty ahead as Procurement of Ground of us.

Investigation, Buried Services and On more positive notes, UK Geoscience graduate decline the geotechnical and and I will report on their progress geoenvironmental community in the next issue. I look forward seems busy with healthy order to virtually seeing more of our books and high tender levels. members in Both LTC and HS2 appear to be the next few steaming full ahead, at least for months. the ground investigation and design phases, which directly Julian Lovell affects and benefits our industry.

AGS Chair The announcement of the release of funding for infrastructure and

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ABOUT THE AGS The Association of Geotechnical and Geoenvironmental Specialists (AGS) is a non-profit making trade association established to improve the profile and quality of geotechnical and geoenvironmental engineering.

The membership comprises UK organisations and individuals having a common interest in the business of ground investigation, geotechnics, geoenvironmental engineering, engineering geology, geochemistry, hydrogeology, and other related disciplines.

EDITORIAL BOARD Julian Lovell, AGS Chair Caroline Kratz, Forum Court Associates (FCA) Katie Kennedy, FCA Calum Spires, Equipe Group Neil Parry, GEL David Entwisle, BGS Jim Poole, Coffey Chris Vincett, Hydrock Vivien Dent, RSK Adam Latimer, Ian Farmer Associates Dimitris Xirouchakis, Structural Soils EDITORIAL STORY If you have a news story or event which you’d like to tell our editorial team about, please contact the AGS on 020 8658 8212 or ags@ags.org.uk. Please note that articles should act as opinion pieces and not directly advertise a company. The AGS is under no obligation to feature articles or events received.

CONTACT US AGS Forum Court, Office 205 Devonshire House Business Centre, 29-31 Elmfield Road Bromley, Kent, BR1 1LT  ags@ags.org.uk  020 8658 8212  Association of Geotechnical & Geoenvironmental Specialists  @agsgeotech www.ags.org.uk

Inside this month’s issue

FEATURE PAGE 22

 COVER STORY PAGE 8 

Working at Height During Trial Pitting - How far is so far as reasonably practicable?

Members of the AGS Geotechnical Working Group respond to an article discussing the value of the Standard Penetration Test.

Steve Everton of Jacobs looks at the hot-topic of Trial Pitting and examines what measures can be put in place to ensure the safety of staff carrying them out.

INTRODUCTION TO THE AGS I&MWG PAGE 16  WG Chair Jonathan Gammon unveils the new AGS Instrumentation and Monitoring Working Group.

BS 10176:2020 TAKING SOIL SAMPLES FOR VOCS PAGE 30  Mike Smith introduces the latest Standard for taking soil samples for determination of Volatile Organic Compounds.

Q & A: JO STRANGE PAGE 32  The AGS Magazine conducts a Q & A with Jo Strange of Card Geotechnics Ltd.

MORE INSIDE

PAGE 4

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News in Short: AGS Video Competition Results

PAGE 34 

Standards Update June 2020

PAGE 36 

Working Group Update Contaminated Land

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News in Short AGS Video Competition – The Results Following on from our hugely successful photography competition, in winter 2019, the AGS launched a video competition to view the industry’s most creative clips.

A whole range of videos were submitted from members including recordings of rigs, ground improvement projects, geology models and concrete testing. The AGS Officers had the difficult task of reviewing each of the entries, and have shortlisted three outstanding clips: •

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1ST PLACE: In Situ Site Investigation, Rail Rig Time-Lapse Video A time-lapse video which shows the simplicity of using CPTs on a railway using an RRV from the on-tracking process. Tests were completed either side of a bridge abutment to provide information about the ground material in order to rebuild a bridge.

2ND PLACE: Harrison Group Environmental Limited, Geology Model Video A geology model representation of an investigated feature. The clip showed how data can be interpreted from geology “sticks” at each investigation location into triangulated surfaces. The resulting output helped to explain what occurred in the area and could be analysed further with tools

such as section profiling.

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3RD PLACE: Jones Bros and BWB Consulting, Sheet Piling and Ground Improvement Project A short video showcasing sheet piling and ground improvement works on a geotechnically challenging project along a dual carriageway link road in Wigan.

Congratulations to In Situ Site Investigation who have won a Fortnum and Masons Tanner Hamper worth £85. The hamper features an assortment of Fortnum’s classics, including sweet and savoury jars, a tea tin, biscuits and confectionery delights. Harrison Group Environmental Limited and Jones Bros & BWB Consulting, have each won a bottle of Champagne.

The AGS would like to thank all those who took the time to enter the video competition.

The overall standard of entries was extremely high, and the judging panel found the task challenging in shortlisting the top three entries.

The top three AGS publications for May 2020 1. Safe Ground Investigations in the Light of COVID-19 2. AGS Guide to Ground Investigation Reports 3. AGS Guide: The Selection of Geotechnical Soil Laboratory Testing To download the publications for free; click here.

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On-Demand Geotechnical Training Equipe Group are excited to announce the launch of their new on-demand geotechnical training platform – GEO Academy.

Combining elements of inperson classroom activities and assessments, as well as media-rich teaching materials, the new on-demand platform will provide specialist geotechnical training, short-courses and general CPD content for all levels of

expertise. The platform will be a centralised catalogue of expert geotechnical knowledge and training, with courses written and delivered by a range of specialists from across the UK. Courses will range from: expert insights into in-situ

testing, instrumentation and monitoring; to wire rope and LOLER awareness; commercial and contracts deep-dives; to optimum corebit selection for rotary drilling.

For further information, visit www.geoacademy.co.uk

FPS Podcast

The FPS has launched their second podcast; an interview between FPS Chair, Steve Hadley and Tony Suckling (Director at A Squared Studio), David Major, (Chair of the FPS Early Careers Group and Expanded Geotechnical) and Dave Trotter (Fatigue Science). The Podcast is sponsored by Soilmec.

David Major discusses the FPS Early Careers Group and looks at why it was formed, and how the group can grow to provide support from University level to those doing their chartership. Director of A Squared, Tony Suckling, talks about advanced geotechnical design techniques and the importance of ground investigation, the RIBA design stages and Eurocode development. Dave Trotter of Fatigue Science joined the discussion from Canada, and spoke at length about the work his company is doing with the FPS, specifically to educate people working in the industry, educate managers of fatigue and learn lessons from research about how fatigue impacts performance as well as safety.

The podcast can be listened to via iTunes, Acast, Spotify and directly here: https://tinyurl.com/ y8n2xnqe

Useful guidance regarding COVID-19 from Beale & Co AGS Affiliate member, Beale & Co have produced several materials including guidance notes and updates in relation to COVID-19 to assist with legal and commercial risks.

These materials can be accessed on Beale & Co’s website: https://beale-law.com/ coronavirus-covid-19-hub.php If you’re an AGS Member and are looking for legal advice, please contact Beale & Co on 020 7469 0400 and quote ‘AGS Helpline’ where the first 15 minutes of legal advice will be free of charge.

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News in Short AGS Awards 2020 Below are the list of recipients of this year’s AGS Awards. We would like to thank all Working Group participants for their hard work over the last year in raising standards across the industry and increasing the profile of the AGS on the whole.

WORKING GROUP Safety

Safety

Safety

Business Practice

Business Practice

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AWARD/ COMMENDATION EXPLANATION NOMINEES Madeleine has been a stalwart of the SWG for a number Award: Madeleine Bardsley of years and her experience and knowledge of working

on contamination sites has been invaluable in producing and reviewing a wide range of publications and guidance documents. Madeleine is a regular attendee at our quarterly meetings and is always keen to be fully involved in the lively and frank discussions.

Steve is a very active member of the SWG and has been a Award: committee member for several years. Steve has been recently Steve Everton involved in providing further input into the updated asbestos risk assessment working in collaboration with the CLWG. Lately, Steve has been instrumental in our current view of the safety of trial pitting from a working at height perspective and is currently working on analysing the questionnaire shared throughout our industry with future magazine articles. Steve also delivered a thought provoking presentation at the recent “Safety in Mind” conference on the subject of trial pitting.

Rosey is a relatively new member of the SWG committee, but Commendation: Roseanna Bloxham has quickly established herself as a key member of the team.

Rosey has contributed and worked on new and current safety guidance. Notably, Rosey delivered an excellent workshop using Lego at the recent “Safety in Mind” conference with a follow-up article in the recent e-magazine.

Although David is the newest member of the Business Practice Award: Working Group, joining in 2019, he has already proved to be David Hutchinson a very valuable member of the team. He has been prolific in providing analysis key to the endeavours of the group and has produced several documents in a very timely manner for review and publishing. We thank him very much for his continued willing and cheerful assistance to the AGS overall and to the Business Practice Working Group in particular.

It goes without saying that Neil, as Past Chair and a longAward: standing AGS contributor, has provided a great deal of value Neil Parry to the Association over the years and his dedication to the AGS cause has been consistent and diligent since 2007. Neil has previously led the Business Practice Working Group and remains an active member, contributing greatly to AGS governance and marketing and providing valuable insight at meetings.

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Business Practice

Commendation: Ken Marsh

Loss Prevention

Award: Jo Strange

Data Management

Award: Roger Chandler

For unfailing support and diligence in participation to Business Practice activities for many years in addition to his responsibilities as AGS Treasurer. Ken has provided invaluable advice and input to the strategy of the AGS through Business Practice contribution.

This is to reflect Jo’s long standing and active contribution to the LPWG over more than 10 years. Jo has been involved in the research and preparation of the Loss Prevention Guidance, Newsletter articles and some Loss Prevention Alerts. Jo has always been generous with her time and always helpful in reviewing and commenting upon many and various documents published by the LPWG. Her comments are always kind, useful and improve the advice. In particular, Jo was a great Chair of the Loss Prevention conference earlier this year and is repeating her contribution in Manchester this coming January. On the basis of all of this contribution, I would very much like to recognise Jo’s significant contribution to the LPWG with an AGS Award.

Roger Chandler joined the AGS Data Management Group in 1999.

The group has proposed him for this Award in recognition of his tireless work on behalf of the AGS at conferences and elsewhere in promoting use of the AGS ‘Electronic Transfer of Geotechnical and Geoenvironmental Data’ format (data transfer format).

Over the last 20 years he also has been very active in promoting the AGS Format throughout the world, including Australia, New Zealand and Hong Kong, but especially in the USA. In 2005, Roger was invited to join a group there which was tasked with creating a global geotechnical data exchange format. Their plan was to use AGS 3.1 as the basis for their XML format.

Executive Committee

Award: Vivien Dent

Whilst DIGGSml now has a good following in the United States, the UK was unable to make a workable version for its users and in 2010 our paths diverged and AGS 4.0 was created.

Roger has maintained his ties to the US project and gives us regular updates on its development. In his new role as Director Geotechnical Information Management at Bentley Systems, he is no longer able to attend all our meetings, but we still hope to see him occasionally.

Viv has led the Contaminated Land Working Group with vigour and enthusiasm and has always been an active member of the Executive Committee. Viv has been instrumental in helping the AGS to develop and deliver extremely high standard conferences and has persuaded high level speakers to be involved. She has also continually encouraged her working group to produce interesting and informative articles for the AGS Magazine helping to keep the members aware of the working group activities, issues and hot topics. She is a great ambassador for the AGS and clearly enjoys her work and long may this continue.

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Ground investigation – Is it time for change?

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delivering our client’s needs he article entitled “are Whilst design, now and in the future. traditional sampling techniques really analysis, and Whilst design, analysis, and that bad” published in April’s construction construction techniques AGS Magazine has provoked techniques have have evolved and benefited much discussion and debate evolved and benefited from market innovation and amongst AGS members new techniques, many of from market and within the industry. the ‘traditional’ investigation The Geotechnical Working innovation and new methods have not changed Group has been exploring techniques many of the in the past 100 years. For how the UK geotechnical investigation methods example, the process of industry can respond to used have not changed driving piles now benefits the demands of our clients in the past 100 years. from instrumentation and updates to Eurocodes and automatic logging of and other standards to deliver construction conditions and investigations that enable project design of the driving process. This enables the piling appropriate quality. This article is intended specialist to feed this data back to designers to put the views expressed in the April article and contractors to allow rapid verification into context and propose how the full range of pile capacity, design modification, and of investigation options can be better used to communication to the supply chain. In deliver projects that meet the challenges of

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is a choice to design either using the old methods or Eurocodes. This is a dangerous path to tread, because the old standards are no longer supported by BSi and effectively are now obsolete. The UK has always been fully committed to using Eurocodes or perhaps more correctly the new British Standards It is true to say that there is often a conflict and Codes of Practice which are fully between cost and perceived complimentary with Eurocode. benefit and for the uninitiated The decision to follow this It is interesting the decisions which route was made many years to read the views determine the methodology ago and was embraced by given on the use of used to investigate the our governing bodies and ground conditions and the the SPT test and the Institutes and indeed the determination of design UK, through AGS and other premise that these parameters is often, if not bodies, has and still does test are often adopted invariably, determined by play a significant role in their rather than rotary cost rather than technical content. coring. requirement or necessity.

It is interesting to read the This conflict has in the past been views given on the use of minimised by using large factors of safety. the SPT and the premise that these tests are Historically, geotechnical engineers have often adopted rather than rotary coring. This used this factor of safety and combined it with is a misconception which has no technical engineering judgement to allow for variations foundation, perhaps we forget that the SPT and uncertainties within the ground, however, was originally developed as a sampling tool it is now far too often just used as a margin for and not an in-situ test. It was configured as error or in many cases poor quality control. a split spoon with an open shoe and in this This latter approach provided the comfort of form is a thick walled sampler in current knowing that even if the results were not that terminology. The number of blows to drive the accurate, it really did not not matter, because sample was originally something which was failure was very unlikely. It is important to note added to provide a bit more information on that whilst there have been few foundation ease of penetration. More importantly under failures as a result of bearing capacity, the Eurocode 7 the SPT is classified as a secondary same is not true of structural distress due to investigation method which should be used differential settlement. This fact reflects more to complement soil strength measurements about our inability to accurately determine soil derived from laboratory testing of Class 1 soil stiffness rather than determine the undrained samples. Unfortunately, in many cases, the shear strength. The advent of Eurocode and SPT is still presented as the primary source of more precisely the use of limit state design and data to interpret in-situ soil strength. partial factors has removed the comfort which The SPT, as we know it today, was first for many years has disguised poor practice or described by Karl Terzaghi and Ralph Peck in inappropriate investigation methods. their book published in 1947. At that time, the It is true that many clients and design equipment had been in use for more than 30 teams have not fully embraced Eurocodes, years as a sampling tool, albeit rather crude. however, there is a misconception that there contrast, the humble SPT, which forms the basis of much of the foundation design delivered in the UK, has not benefited from any significant improvement in the way information is gathered about the in-situ state of the ground.

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The sample is invariably highly disturbed and of limited value. The original equipment was modelled around similar equipment used in the USA and attributed to Colonel Charles R Gow in 1902. The original sampler, which was 1 inch in diameter, was driven at the bottom of the borehole using a 110lb hammer. Around 1927, part of the Raymond Piling Group, the Gow Company began using a split spoon sampler of 2 inch diameter. Around the same time, a similar system was being used by Sprague and Henwood. In both systems the weight was winched by hand and released at a fixed height. The split spoon sampling tool which comprised a thick walled tube with a cutting shoe on one end was driven into the bottom of a borehole with blows from the hammer. The use of powered winches was not reported until 1937. The equipment was not standardised and it is recorded that the drop weight ranged from 110lb to 140lb whilst the height the weight was dropped was related to that which men could comfortably lift, usually 30 inches. It was not until Terzaghi and Peck (1947), when describing the sampling system, suggested that the number of blows be recorded as those required to drive the sampler 1 foot following seating the sampler 6 inches beyond the base of the borehole. Terzaghi suggested that by recording the number of blows valuable information might be obtained at little cost and that the information may be of some use in soils where little other information could be obtained such as granular (coarse) soils. Up to this point there were no other tests which might indicate the potential competence of granular (coarse) soils. Terzaghi proposed to use a 60 degree cone rather than an open shoe and then count the number of blows taken to drive the cone a given distance. This has been standardised into the test form we use today. It should also be noted that the test has only recently been standardised around the world and in some countries the test still does not follow a unified method.

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The open shoe often blocked off on gravel and would then produce erratic results. For much of the next 70 years or more, the SPT was used to give something to assist engineers to determine the nature of granular (coarse) soils. Various authors have attempted to derive more useful parameters from these basic results. Many of these relationships are based on sound research but most are only relevant to the original site the work was carried out on and are not readily transposable to other sites.

It was in the 1980s that the now common use of taking an SPT in fine soils began to gain acceptance, again, several authors attempted to develop relationships which are at best tentative.

of the equipment. However, The SPT test is at best crude the variation in the obtained and often a blunt tool used The SPT test is at to provide information best crude and often energy ratio values reflects the inherent uncertainty of debatable value. In a blunt tool used to of the test and probably practice the cone is driven provide information of also points towards the dynamically over a distance debatable value. variation in the different which far exceeds any strains equipment used to measure the ground will be subjected energy ratio by different to by loadings from foundations. test houses. It also highlights how the test can The SPT is certainly not a replacement for be affected by numerous other factors which laboratory testing of good quality soil samples were described by Clayton, 1982 as ‘parasitic no matter how cheap. effects’. The suggested energy ratio calculation It is interesting to see the energy ratio can create some inconsistencies between (calibration) test results for the five hammers individual calibration tests and test houses as it used by Soils Consultants. It is true that the only requires the energy ratio to be reported as introduction of an annual inspection and test the mean value of at least five measurements has undoubtedly improved the maintenance

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to note that BS EN ISO 22476 - 3 was published (blows). Extensive testing and analysis by the in 2005. However, it was not until 2008 Equipe Group has proven that by recording at when Equipe introduced an least ten blows can provide independent testing service a more representative mean The uptake were we in the UK, able to value and can also eliminate of such testing even measure the energy the effect of spurious results. has improved in ratio.

Some test units simply take recent times but it is the average of the five blows The previous article, no matter how wide the range interesting to note published in the May edition of individual determinations that BS EN ISO 22476 of the AGS Magazine, has might be. It is clear the test - 3 was published in presented data showing a should be more rigorous, wide scatter of test results 2005. However, it was limiting the range not to from various methods not until 2008 when exceed values of say no (Graph 1). This graph more than 10% of the mean.

Equipe introduced an provides evidence that the Note that BS EN ISO 22476independent testing London Clay is far from 2 suggests that measured service were we in homogeneous, with values energy for dynamic probing of Cu and SPT varying the UK, able to even equipment should not considerably through measure the energy deviate more than 3% of the the formation. This is not theoretical energy. Hammers ratio. surprising when considering testing outside this range the work of King et al, 1981 should be considered as defective which identified some four divisions and 12 as any results obtained from this equipment subdivisions in the formation. Indeed, a visit to are unlikely to be reliable, consistent or the classic exposure at Whitecliff Bay, IOW will representative. The uptake of such testing has demonstrate how much variability is contained improved in recent times but it is interesting within the sequence.

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U100 sample taken in a stiff laminated clay showing acute sample disturbance (The lump at the base is wax.)

The data in Graph 1 reinforces the need to investigate each site as an individual location and to use the best possible methods to obtain reliable data to ensure that the parameters sourced are as representative as possible for the specific design requirement of any particular site. Indeed, the data presented demonstrates how difficult it is to try to over simplify the data and analyse amalgamated results. Designers all too frequently seek to draw straight lines which are used as design lines or even give an upper and lower bound.

This design approach often ignores the natural variability of the materials. This variability is further demonstrated by Standing, 2018 who used water content to determine the boundaries between the divisions identified by King. His work clearly identifies the variability of water content in the various divisions and geotechnical practitioners are very aware that water content will directly affect the measured undrained shear strength.

Whilst not wanting to disregard all of the current investigation methods used to obtain geotechnical parameters for design purposes, it is important to bear in mind that sampling methods which use driven

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thick walled sampling tubes will produce disturbance of both structure and water content distribution through the sample. This is clearly demonstrated by the fact that much of the London Clay is laminated but it is very rare that these laminae are seen in driven tube samples whilst they are seen to be present in high quality rotary cores. Tube samples usually exhibit a softer outer skin which is developed by pore water suctions being developed as the tube is driven, causing water to migrate from the centre of the core to the outer edge. This moisture migration will affect the undrained shear strength when tested in the triaxial apparatus.

The variability of the London Clay is also clearly exhibited by CPT tests carried out within the sequence. These demonstrate the variability over short distances and reinforce the argument that the formation does not conform to straight lines. Therefore, designs which result from straight line analyses are likely to be prone to simplifying the in-situ ground conditions which could lead to errors in interpretation..

For many years the geotechnical community

have chosen to ignore the obvious and often stated limitations of both the SPT test and driven samples. Of the SPT, Clayton et al stated that in granular (coarse) soils, the SPT results can only be correlated in a general way with physical properties whilst in cohesive (fine) soils the results can be regarded as generally unreliable. This was further reiterated in 1995

by Clayton and again in 2001 by Prof. Paul Mayne. Simons, 2001 cite sound research to support these opinions.

The evidence produced by many authors shows that both thick walled sample tubes and SPT testing provides very poor results and cannot be recommended for the reliable determination of design parameters. Eurocode clearly labels these samples as Class 3 or 2 and as such unsuitable for strength or deformation testing. The UK’s recommended design methods using codes which have been decades in their production and compiled by respected members of our engineering community require that good practice must be followed to ensure a safe and economic design.

The essence of Eurocode is one of a complete document which serves to ensure the design method is supported by good practice and not a document where specific parts can be lifted as one feels fit, whilst other parts are ignored.

Surely it is time that we embrace the technology at our disposal to ensure ground investigation is conducted properly and to the standards we would expect in almost any other walk of life. Relying on the results of a steel rod or tube knocked into the ground does not constitute best design practice in the 21st century.

We are not advocating that the SPT is going to be consigned to the museum, however, as a start point we must surely be able to take out some of the errors which are sadly still apparent, this might include electronic measurement of the depth of penetration along with the number and energy of blows

delivered to the rods.

There is still much to do if we are to move on from the SPT and driven sampling methods, however, we do need to put our faith in our ability to find solutions. It is time to invest in research to develop reliable methods to determine water content, density and stiffness.

It is only by doing this, that we will be able to provide workable economic designs and alternatives to outmoded and scientifically unsuitable methods.

There is little point in appeasing the client by keeping costs as low as possible and then providing the wrong answer which can tarnish professional reputations and test the strength of your PI insurance..

References King C. 1981. The stratigraphy of the London Basin and associated deposits. Tertiary Research Special Paper, 6 Bachuys Rotterdam.

Standing J. R. 2018. Identification and implications of the London Clay Formation divisions from an engineering perspective.

Proceedings of the geologists association 2018.

Clayton C.R.I. 1995. The Standard Penetration Test (SPT): Methods and Use. CIRIA Report 143.

London: CIRIA 143.

Simons N. E. and Menzies B. K. A short course in foundation engineering. (2nd edition) Thomas Telford Publishing London 2001.

Mayne P. W. (2001) Ground property characterisation by Insitu tests. Proc.15th ICSMGE Istanbul August 2001.

British Standards Institute (2015) Code of Practice for Site Investigation.

Article contributed by Peter Reading, P R Geotechnical Consulting Stephen Lawrence West, Ramboll

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ShapeArrays installed in the Kennington Loop in the vicinity of the step-plate junction as part of the extensive I&M undertaken for the Northern Line Extension to London’s Underground

Introduction to AGS’s Instrumentation and Monitoring Working Group (I&MWG) In March last year an international Instrumentation and Monitoring (I&M) Conference in London concluded with a Ground Engineering Round Table debate intended to identify matters within the I&M sector that needed attention.

It became apparent that there were key areas of concern about the need for education, training, and qualifications.

Taking an active part in the Round Table debate was Jonathan Gammon, Non-Executive Director and Advisor at I&M specialists Geotechnical Observations Limited and a PastChairman of AGS.

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Jonathan believed that AGS was well-placed to take forward the matters discussed and subsequently submitted to AGS a proposal for the formation of an Instrumentation and Monitoring Working Group (I&MWG). AGS’s Executive approved the proposal towards the end of 2019 and invited Jonathan to be its Leader.

The role of I&M “It’s easy for those of us directly involved in I&M to understand the importance of I&M” Jonathan recognises “but I hope the following diagram - my “GeoWheel©” - illustrates just how important it is:

The GeoWheel© is a means of: •

showing how ground engineering can be divided into distinct activities and how these activities interact,

•

introducing Clients to the scope and range of services available to them,

•

showing the nature, ownership, and progression of reports that are generated during a project’s lifecycle, and

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identifying key areas of “know-how” required of staff seeking professional qualifications such as Incorporated Engineer (IEng), Chartered Engineer (CEng), and Chartered Geologist (CGeol)

The four activities beyond the rim of the GeoWheel© (e.g. Project Management), hold steady the dynamics of the GeoWheel©.

The “R&D” activity that features at the hub

of the GeoWheel© is short-hand for a range of activities such as Advanced Numerical Modelling, Physical Modelling, Innovation, and the like … as well as Research & Development.

I&M lies at the hub of the GeoWheel© - indeed, forms its axle - and is therefore critical to both the rotation and the stability of the diverse activities around the GeoWheel© and those neighbouring activities at the hub itself.

I&M relates not only to geotechnical and ground engineering, plus engineering geology, but also to tunnelling, environmental engineering (including contaminated land and environmental monitoring), and structural engineering.”

It is important to note that the GeoWheel© does not identify the necessity to consider I&M on a Whole-Life basis, taking in longterm as well as baseline requirements.

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Photo Credit: Derek Egan, Remedy Geotechnics

research and development, the design of and specification of I&M, the procurement of I&M, the installation of instruments, and the interpretation and presentation of I&M and related software.

These may extend well beyond construction or implementation and include asset management, decommissioning, and demolition.

The Aims of the I&MWG The importance of I&M, the need for it to be placed on the education curriculum, the need for formal programmes of training, and for there to be recognised qualifications for all those involved in I&M are the key drivers of the Aims of the I&MWG: •

•

•

To promote geotechnical, structural, and environmental instrumentation and monitoring (I&M) to the geotechnical, geoenvironmental, and wider ground engineering community.

To raise awareness to clients, asset owners, their professional advisors, and related parties, of the need for baseline (i.e. preimplementation/construction), project implementation, and post-implementation I&M for all types of projects and asset management.

To be a focal point for the education and training of those engaged, or seeking to be engaged, in I&M including, but not limited to: the design and manufacture of instruments and related software and

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•

To identify and define an appropriate data format to effect the transfer of I&M data for interpretation, analysis, and presentation.

These Aims are contained in the “Terms of Reference and Modus Operandi” document as a necessary feature of the proposal to form this new Working Group.

The document then sets down how these Aims are to be achieved through the Group’s Activities, by: •

a) promoting the activities of the I&MWG to the AGS Membership and to the wider industry.

•

b) maintaining a watching brief on I&M activities of the wider national and international engineering and related communities, and reporting these to the membership.

•

c) organising and running I&MWG initiatives and events on behalf of AGS.

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d) being involved closely in the drafting and reviewing of national and international

standards, codes of practice and other definitive guidance.

•

e) being represented on national and international Technical Committees, and the like, in addition to d), above.

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f) being pro-active at all levels of education and technical and professional training.

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g) establishing and promoting recognised qualifications for all those engaged in I&M work.

•

h) striving to become a leading national authority on I&M matters affecting the AGS Membership and the wider industry.

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Alice Shrubshall, BuroHappold Engineering

“In time, and as we work our way through our planned activities, the size of the Group will grow, probably to a maximum of 20 members”.

Promotion of the I&MWG beyond current AGS Members

Existing Members of AGS were contacted to identify individuals who could be the Founding Members of the I&MWG.

Promotion of the I&MWG within AGS and the Founding Members of the I&MWG Existing Members of AGS were contacted to identify individuals who could be the Founding Members of the I&MWG. “My ambition was initially to establish what I saw as a “critical mass” of at least ten members forming the I&MWG”, reports Jonathan.

The Founding Members of the I&MWG are: •

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Jonathan Gammon, Geotechnical Observations - [I&MWG Leader]

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Neil Atkinson, Arcadis

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Paul Bailie, Arup

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Katharine Barker, Campbell Reith

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Tom Birch, Geotechnics

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Philip Child, Bentley Systems

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Chris Crosby, Bridgeway Consulting

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Emma Leivers, Geotechnical Engineering

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Mario Markos Miletic, Fugro

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Rachel Monteith, BuroHappold Engineering

•

Andrew Ridley, Geotechnical Observations

Some companies and organisations who are actively involved with I&M, including public and private sector Client organisations and institutions such as the Royal Institution of Chartered Surveyors (RICS), are not Members of AGS.

The I&MWG has also been brought to the attention of a wider audience as a result of articles published by Ground Engineering on its website www.geplus.co.uk “This is a welcome opportunity to thank Michaila Hancock at GE, in particular, for her articles about I&M and the I&MWG.” Jonathan adds.

First Meeting of the I&MWG and Current Status of Aims and Activities As a result of COVID-19 restrictions, the first meeting of the I&MWG took place online on Friday 24 April 2020.

With reference to the Aims and related activities: a. a) Action relating to promotion of the Group has already been described in this article. Although the cancellation of the AGS Members Conference in April prevented an introduction to the I&MWG taking place at that time, this article is intended to make up for that lost opportunity. b. b) Concerning wider national and international communities, contacts have already been established with various

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organisations and individuals. These “Field Measurement in Geomechanics” include leading I&M practitioner John and is a member of the ISO’s Technical Dunnicliff, author of the world-famous Committee ISO/TC182/WG2 “Monitoring in book “Geotechnical Instrumentation Geotechnical Engineering”. Andrew is also for Monitoring Field Performance”, Chairman of the Organising Committee for who asks the I&MWG to acknowledge the 12th FMGM Symposium to be held in “the importance of human factors in early September 2022 at Imperial College, geotechnical and structural monitoring London. programs”. A proposal to form a parallel f. g. and h. The I&MWG has already been I&MWG at AGS in Hong Kong was represented at training events [f)] including surprisingly unsuccessful although a British Drilling Association Seminar and AGS(HK) have identified a point of it plans to extend its engagement with contact with their existing Working education and technical and professional Groups. A favourable response has been training and the establishment of received from the British Tunnelling recognised qualifications as soon as Society to contribute to revisions to possible. their “Tunnelling Specification” and The I&MWG will be contributing “Monitoring Underground to an AGS initiative Matters such as Construction” documents. relating to Procurement as data format and c. A one-day AGS seminar influenced by the Institution (“Critical Links in Ground management will be of Civil Engineer’s “Project Engineering”), was tackled in conjunction 13” and encompassing planned by AGS at the with AGS’s Data related issues such as time the I&MWG was Specifications and NEC4 Management Working formed. Scheduled (and its application, for Group and there are initially for 15 July, a example, to Ground postponed date for this other examples of Investigation). event in November is

“

currently being sought, at which time it is likely to take the form of a webinar (c/o Caroline Kratz at AGS).

where an ability to engage directly with another AGS Working Group will be to the I&MWG’s advantage.

d. Regarding standards and the like, AGS’s revision of the “Yellow Book” - the UK Specification for Ground Investigation – will now include input from the I&MWG. BSI’s BS5930:2015+A1:2020 “Code of Practice for Ground Investigations” has just been published and includes a section on I&M. e. Relating to Technical Committees, I&MWG member Andrew Ridley is Chairman of the ISSMGE’s Technical Committee TC220

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Matters such as data format and management will be tackled in conjunction with AGS’s Data Management Working Group and there are other examples of where an ability to engage directly with another AGS Working Group will be to the I&MWG’s advantage.

And now there is a new matter needing the I&MWG’s attention: The impact of COVID-19 on I&M in the future.

Contact for the I&MWG To contact or register interest in the I&MWG, please email Katie Kennedy at ags@ags.org.uk

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Working at Height During Trial Pitting How far is so far as reasonably practicable?

T

his paper was the subject of a presentation at the AGS Safety in Mind conference in November 2019, and started by asking “why this subject, and why now?�. During a prior AGS Safety Working Group meeting, we had debated whether the Health & Safety Executive approve or agree with the AGS guidance notes? In particular we debated whether common UK trial pitting methodologies complied with the Work at Height regulations 2005; and specifically, we

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were interested whether the common practice of standing or kneeling close to the edge of an unprotected trial pit, 2, 3,4m+ deep might be deemed in hindsight to not comply with the law. The purpose of the presentation was to raise awareness of the issue to younger practitioners, remind senior practitioners and managers of their duties, to promote debate about the sufficiency of current industry practice, and whether current practice meets the legal benchmark of good practice.

or could do more to manage the risk from working at height adjacent to unprotected trial pit edges. The time to have this debate clearly is not when a HSE inspector is questioning you following a serious accident, but preferably by industry collectively and in advance of such an incident ever occurring.

I have been involved in trial pitting since the 1980s, and have learned much about the ground from being up close, which a trial pit allows. My experience of trial pits is that it can be dirty, tiring, and potentially hazardous work. However, they are often fun, provide good information and experience, and sometimes are even a fabulous day out. They are economical, quick to organise, undertake and report.

Conventional machine dug trial pits expose the logging engineer to an unprotected edge of potentially 3 to 4 m depth in order to undertake at least part of their task. This Introduces a risk of becoming unbalanced or tripping at the edge whilst observing, taking measurements, sampling or photography. In my 30 years’ experience I am not aware of a logging engineer falling into a trial pit. A questionnaire survey sent out to AGS members in summer 2019 also concluded that there is no knowledge within the membership of falling into trial pits, although we subsequently became aware of anecdotal experience of 1 non-injury fall into a pit filled with groundwater! Whilst we know Although used generally that trial pit faces can collapse safely for many decades, and whilst it is theoretically The Work at trial pitting does present possible for such a collapse Height Regulations a number of hazards. The to involve the logging 2005 clearly apply Work at Height Regulations engineer, experience over 2005 clearly apply to this to this work, and a substantial period of work, and place legal duties time shows us that logging place legal duties on on employers. Very few engineers don’t fall into employers. practitioners have ever trial pits, and, therefore, experienced an incident involving the proven probability is a fall into a pit. Nevertheless, we have the extremely low to negligible. opportunity to consider whether we should However, probability is not the only

“

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component of risk, severity of “so far as is reasonably The consequence of consequence also has to be practicable” - how does an of falling two, three considered. The consequence employer know how far they of falling two, three or four need to go? The HSE guide or 4 m into a trial pit is metres into a trial pit could “Working at height: a brief likely to be severe, it is be severe, and involve guide” states that “low risk likely to involve broken broken bones, a broken relatively straightforward bones, a broken neck or neck or worse. Using typical tasks will require less effort.” worse. industry risk assessments, They go on to say that “there a combination of low or very will also be situations where low probability along with medium common sense tells you no to high, to very high consequence generates particular precautions are necessary “. Whilst a medium to high, to very high risk. The risk this does not provide any specific guidance is significant, such that measures need to be in relation to trial pits, it does acknowledge considered to mitigate it. low risk situations (albeit not necessarily low probability situations). By extension, higher “SFARP” and the Work at Height risk situations require greater controls.

“

Regulations

Regulation 6 of the Work at Height Regulations 2005 is titled “avoidance of risks from work at height”. It describes a hierarchy which employers are required to work through and give consideration to when planning work at height, requiring at each level a consideration as to whether the available controls reduce the risk “so far as reasonably practicable” before discounting a control and using a lesser control.

But what is the required level of the duty

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Case law in respect of SFARP leads us to Edwards v National Coal Board 1949, which established the principle that the quantum of risk is placed on one side and the sacrifice whether in money, time or trouble involved on the other. If it can be shown that there is gross disproportion between them, the duty has been discharged.

So where is trial pitting practice in the 21stcentury in relation to SFARP - does it pass “the gross disproportion” test? HSE suggest

in their report “Reducing Risk Protecting People” (“R2P2”) 2001 that they regard a risk as not significant if past experience shows the risk to be extremely low (note “risk” not probability). HSE also state that they would consider sources of good practice, standards or guidance agreed by bodies representing industry. They would consider an assessment of the extent to which the practices have achieved general acceptance, and they will decide whether adoption of any authoritative good practice precautions is an adequate response to the hazards. HSE then say that “in most cases adopting good practice ensures

that risks are effectively controlled”.

However, HSE go on to say that a universal practice in industry may not necessarily be good practice or reduce the risk sufficiently; they make it clear that duty holders should not assume that it is. They state that there will be times when existing practice is found to result in inadequate control of risks. So, we come to the question which opened this presentation: is current industry guidance, including AGS guidance on trial pitting and working at height, representative of good practice such that the HSE would consider it as an adequate control of the risks?

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Headline responses to the AGS Trial Pitting Survey 2019

TOPIC Guidance used when planning trial pitting

INDUSTRY RESPONSES Most respondents stated they use the current AGS trial pitting guidance, and a number stated they have in-house / company guidance of some kind.

Several respondents suggested that they refer to BS5930 although there is only limited safety guidance there. A number of respondents refer to HSE “working at height a brief guide� and HSE CIS614 Excavations, although neither of these provide much useful guidance in relation to trial pits.

No respondents identified the existing AGS guidance on Working at Height as informing their working arrangements.

Competence to Almost all respondents had some form of assessment of competency and a period of supervised handholding typically 3 to 6 months. work near an unprotected Some have in-house trial pitting & work at height awareness elements of trial pit edge training Many use CITB SMSTS or similar.

Most use CSCS, however usually not on its own.

Many respondents prevent access anywhere near the trial pit by other workers

How duty holders address The vast majority do not make use of protection such as barriers or fall the hierarchy prevention/protection using harnesses, mostly on the grounds of perceived or of controls in experienced impracticability.

Regulation 6.

Some practitioners have tried to use mobile barriers, staging boards, fall protection harnesses Some practitioners try not to use trial pits.

Some practitioners leave the JCB bucket in the hole to reduce height of fall.

Demonstration No respondent stated that they undertook such a specific assessment of SFARP at Some respondents believe that SFARP was embedded in their company each level of work procedures and training of staff, the use of risk assessments, method the hierarchy, statements and CDM design risk assessments, and through following AGS and for example HSE guidance documents. by considering risk against cost and benefit.

Some respondents suggested that they do not provide fall protection for Reasons walking down a flight of stairs, where there is clearly a fall hazard of a highly why control frequent nature, and potentially just as severe as a fall into a trial pit perhaps. measures are considered to Respondents said that the staff are aware of the risk of falls into trial pits, and be SFARP they have the ability to stop work if they consider it unsafe.

Some respondents referred to the HSE guidance which flags up that there are some low risk solutions suggesting precautions may be unnecessary.

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The AGS Trial Pitting Survey 2019

widespread belief throughout industry that other potential methods such as barriers In order to get a better understanding of and harnesses, even remote tools, were modern common practice, the AGS Safety impracticable on the basis of cost, Working Group circulated the introduction of other more It would appear a questionnaire to the prevalent hazards and risks, membership in summer that a specific and the maintenance and 2019. The main outcomes consideration of SFARP inspection requirements and were summarised at the training. Many respondents / gross disproportion 2019 conference, and key is not an adopted basis believe that such measures headlines repeated hereafter. are not necessary nor of decision-making These headlines are provided appropriate, given the very in the table to the left. within the industry. short duration of a trial pit.

“

Some respondents believe that SFARP was embedded in their company work procedures and training of staff, the use of risk assessments, method statements and CDM design risk assessments, and through following AGS and HSE guidance documents.

Finally, respondents were asked what additional controls they would consider adopting if it could be achieved practicably. Responses included “… a safe excavation cover…” ; “… a barrier that was lightweight, affordable and practicable, which could be used to protect up to the edge or even over The questionnaire the excavation …” ; “… responses extendable trial pit covers presented a widespread …”; “… purpose designed belief throughout lightweight edge protection barrier system …”; “… an industry that other open lattice to prevent a fall potential methods to no more than ground level such as barriers and …”; “ … a standard type of harnesses, even barrier system, aluminium, remote tools, were easily folded up and deployed”. impracticable on the

It would appear that a specific consideration of SFARP / gross disproportion is not an adopted basis of decisionmaking within the industry.

Note however that it is not a legal duty to demonstrate SFARP, it’s just a legal requirement to be SFARP. Many respondents referred to the very low probability of an incident. Comments included “ … falls from height incidents basis of cost... in company history were Tolerability of Risk zero …”; that “… there is not a We’ve noted the potential great deal of empirical evidence and the risk of a fall, looked at the law and to say there is a recognised pattern or trend guidance, and at a subset of industry views on of significant danger of falls...”; and a number trial pitting. Does it help us determine whether of respondents stated that in circa 20 to 30+ current practice is good practice, and whether years, they have never encountered nor heard we need to be doing more? of any injury from falling into a trial pit. Finally, many respondents reiterated that trial pitting Perhaps instead we can ask ourselves: “Can is an essential method of investigating the we tolerate the consequence of a fall?” HSE ground. state (“R2P2”) that “tolerability does not mean acceptability. It refers to the willingness The questionnaire responses presented a

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Hierarchy Element

Normal Controls

Possible Alternative Controls

Comment

Eliminate

•

•

Ban Trial Pitting

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Introduces loss of business

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Consider Alternative investigation

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Cost and delay in GI

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Work from within MEWP

•

Usually unstable ground

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Cost

•

Introduces risk

Barriers which allow close viewing but fall precention “Viewing Bridge” / Platform

•

Examples are heavy, require load testing or similar, maintenance, tranportation

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Reduce mobility; introduce trip hazard; anchor point not certain

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Netting / Lattice Trial Pit Cover

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Not been used in this scenario

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Fall protection harness / lanyards and fixed point

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Difficult to guarantee a Robust fixed point

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Air bags

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Air bag has to come out and go back

•

Escape harness worn

Keep non-logging workers away from Pit

Work from Work Place

Prevent Fall Collective Protection

Very few controls from current practice are within the higher levels of the hierarchy, especially the “Prevent Fall”

•

Individual Protection Minimise Distance and Consequence of Fall

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Step / Bench the far end of Pit

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Place JCB bucket in hole

Minimise the Consequence

Other Measures

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Work from furthest nattow end (less risk of pit collapse)

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Keep spoil (and trip hazards) away from the edges of pit

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Use “selfie” stick to take photos

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Competence, Experience and Training of logging staff

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Emergency rescue plans

to live with a risk to secure benefits, in the confidence that it is being properly controlled.

This means that we do not regard it is negligible or something we might ignore rather as something we need to keep under review and reduced to further if and as when we can”. And that is the point of this initiative from AGS: to keep our measures under review.

Were one to examine the adopted common controls against the levels of the Regulation 6 hierarchy, we see the majority of our current controls sit very close to the bottom of the hierarchy, and particularly in the “others” category. There is a noticeable gap the within the “prevention of falls” and also the “Minimising the distance and consequence of falls” levels, conventionally those areas where other industries focus their controls.

Over the past decade at least, various practitioners have experimented with the use of harnesses to some fixed point, and staging

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boards with fixed scaffold barriers to view trial pits from, and encountered impracticability’s, not least the consequent and guaranteed introduction of a number of other risks which are more likely to cause an injury.

However, using the benefits of modern innovations that are now available to the market, there are products which are beginning to be used in the construction industry to minimise fall distances in particular, and whose prime benefit is that they are lightweight and portable. AGS would be very interested to gain feedback of the use of such equipment for trial pitting.

In conclusion, trial pits are immensely valuable to good ground engineering. Much of that only comes from seeing first hand into the pit from close up; that involves approaching the edge and crouching down; it allows the taking of well composed photographs of features that you only see because you can look inside. The

time of exposure to risk, and the probability of falling into a trial pit when logging is low to very low and possibly unheard-of. However, the consequence of a fall could be a serious injury or even fatality; certainly life changing. If we wish to continue to use trial pits: 1. ethically we should only specify them when we are really going to make proper use of them 2. we should continue to look to use modern technology to improve our protection from falls from height.

3. we should think more about emergency arrangements (including a rescue plan), in advance of when we need them.

AGS are establishing a trial pitting subgroup of the Safety Working Group and would be interested to hear your experiences, viewpoints or potential involvement.

References 1. https://www.ags.org.uk/content/ uploads/2019/11/Working-at-Height-duringtrial-pitting.-How-far-is-So-far-as-isreasonably-practicable-Steve-Everton-Jacobs.

pdf 2. The Work at Height Regulations 2005 http:// www.legislation.gov.uk/uksi/2005/735/ contents/made 3. HSE 2014 Working at Height :a Brief Guide.

INDG401 Rev 2 https://www.hse.gov.uk/ pubns/indg401.pdf 4. https://www.hse.gov.uk/construction/ safetytopics/excavations.htm 5. https://www.hse.gov.uk/pubns/cis64.pdf 6. https://www.ags.org.uk/item/ags-guidancefor-the-safe-excavation-of-trial-pits/ 7. https://www.ags.org.uk/item/guidance-onwork-at-height/ 8. Reducing Risk, Protecting People (R2P2) HSE Books https://www.hse.gov.uk/risk/theory/ r2p2.pdf 9. Edwards v National Coal Board [1949] 1 KB 704; CA [1949] 1 All ER 743

Photo Acknowledgements Oxford Safety Components Ltd; Structural Soils Ltd; Jacobs; BAMRitchies; Article contributed by Steve Everton,CEng MICE, Construction Health & Safety Registered (Advanced) Jacobs

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Photo Credit: Lustre Consulting

BS 10176:2020 TAKING SOIL SAMPLES FOR DETERMINATION OF VOLATILE ORGANIC COMPOUNDS (VOCs) – SPECIFICATION

T

his new standard is intended to raise the reliability of sampling soils for determination of VOCs in the UK, by introducing methods that have been common use in countries such as Australia and the United States for over twenty years.

It has been known for decades that the methods commonly used in the UK do not provide reliable results and can lead to loss of VOCs during sampling, and consequentially underestimation of potential risks to humans and other receptors.

The primary purpose of the draft standard is to provide risk assessors and managers with data that is as representative as possible of conditions in the field, in relation to volatile elements that might otherwise be lost in the sampling and analytical processes. In this context, it is the limits of detection of concentrations in the field that are of primary importance, rather than the limits of detection in the laboratory, although of course the latter can also be a major influence on the former.

The introduction of the new standard will have a significant impact on how companies carry out sampling for VOCs and require close cooperation between those carrying out field work and analytical laboratories.

BS 10175:2011 + A2:2017 states in Clause 8.3.2 that when collecting samples for determination of volatile compounds the sampling technique employed should minimise the loss of volatiles. It is noted that a methodology for the collection of soil samples to minimize loss of volatiles is given in BS ISO 18512: 2007 (this refers to methanol immersion). The new standard should make it

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easier to comply with this recommendation.

BS 10176 will be a standard specification which means that its requirements must be closely followed to claim compliance. It thus differs from other standards such as BS 10175 and the BS ISO 18400 series which provide guidance and permit, and indeed rely on, the user using their judgement when applying them.

The new standard specifies sampling procedures for application in the field.

Analytical procedures are outside of the scope of the standard and the standard makes clear that it is the responsibility of laboratories to adopt analytical procedures that will provide accurate analytical results for samples as presented to them.

Laboratories are required by BS 10176 to provide pre-prepared sample containers complying with the specification provided in the standard. These are to be used in the field in strict accordance with the procedures described in the standard. Samples must be transported to the analytical laboratory in strict accordance with the prescribed method.

As mentioned in the Introduction to the standard, the use of methanol immersion to preserve samples containing VOCs is already required or recommended in a number of British Standards. The procedures specified in the standard amplify those in BS EN ISO 15009, BS EN ISO 16558-1, BS ISO 18512 and BS EN ISO 22155 for the application of the methanol immersion method. The specification also introduces procedures for application of the sodium hydrogen sulfate (sodium bisulfate) solution immersion method.

Preparation of the New Standard Approval for the production of the standard was given by BSI committee EH/4 in October 2017. The decision was “advertised” in an -mail dated 31 October 2017 widely distributed to the contaminated land community by Mike Smith, the Vice-Chair of EH/4. Inter alia, the e-mail invited applications to join the Drafting Panel.

The Drafting Panel began its work in May 2018 under the leadership of Geraint Williams. The Draft for Public comment (DPC) was circulated in July 2019.

The draft standard was prepared drawing on existing published guidance and standards, and the personal experience of the members of the Drafting Panel and others. It was recognised and anticipated that there were points of detail that laboratories, consultants and others might query. However, none of the comments submitted via the regular BSI process, suggested that there was anything fundamentally wrong with the standard and all such comments were readily dealt with following the usual BSI comment review process.

The inclusion of methanol immersion in these existing standards is an indication that it is internationally recognised as a desirable methodology for certain purposes and as noted in the standard, there are also descriptions of the procedure in standards and guidance in the USA and other countries. In addition, a number of major UK consultancies already make use of such methods on a regular basis and there is reference to it being used in the UK at least twenty years ago. It is not a novel procedure and it was consequently considered reasonable to assume that at least some UK laboratories are already familiar with the process.

The use of immersion in sodium hydrogen sulfate solution is not so well known in the UK but it is a standard procedure in the USA and other countries.

The procedures described in the existing BS

ISO standards are not very precise and so it was deemed desirable to produce a more detailed specification that would help to ensure consistency of application and would be amenable to auditing (by UKAS etc. or clients as part of QA/QC) if required. Although the specification is of necessity prescriptive, it does recognise the need for flexibility to permit application in a variety of situations. Detailed procedures can always be deviated from provided what has actually been undertaken and the reasons for the deviation are properly justified and recorded.

Feedback to BSI on experiences of application of the new standard will be important to its successful application and help to ensure that it can be updated as necessary in due course.

Feedback and queries should be sent to the Jessy Mathew, the Manager of BSI committee EH/4 (jessy.mathew@bsigroup.com)

References: BS 10175:2011 + A2:2017 Investigation of potentially contaminated sites – Code of practice BS EN ISO 15009 Gas chromatographic determination of the content of volatile aromatic hydrocarbons, naphthalene and volatile halogenated hydrocarbons – Purge-and-trap method with thermal desorption; BS EN SO 16558-1 Risk–based petroleum hydrocarbons Determination of aliphatic and aromatic fractions of volatile petroleum hydrocarbons using gas chromatography (static headspace method); BS ISO 18512 Soil quality – Guidance on long and short term storage of soil samples; BS EN ISO 22155 Gas chromatographic determination of volatile aromatic and halogenated hydrocarbons and selected ethers – Static headspace method

Article contributed by Mike Smith M Smith Environmental Consultancy

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Q & A with...

Jo Strange MEng CEng CEnv FICE FWES MIEnvSc SiLC Job Title: Technical Director Company: Card Geotechnics Ltd Brief Biography: I am a chartered civil engineer and environmentalist with over thirty years of experience. I’ve worked for multi-disciplinary consultancies before joining specialist geotechnical and geoenvironmental consultancy, CGL. I am responsible for delivery of mostly brownfield projects involving due diligence, audits, planning, management, design, specification, implementation and interpretation of site investigations, risk assessments and remediation. I occasionally take on Expert Witness projects also. I manage SHEQ across the company and supervise technical staff towards Chartership with the ICE and IES. I am a STEM ambassador and involved with the ICE as a Reviewer, on Standards Panel and author of their guidance on Contaminated Land.

Away from work, my passion is my horses, especially side saddle riding and Cleveland Bays.

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What or who inspired you to join the geotechnical industry?

What does a typical day

It happened a bit by accident. entail?

My MEng was in civil and There isn’t really a typical day, environmental engineering as every day is from Liverpool different, with University, There isn’t the numerous when really a typical projects on environmental day, as every day is the go at any engineering different, with the one time and was still in my various numerous projects its infancy. I joined Mouchel on the go at any one management as a graduate time and my various roles. and was duly management roles. The day always dispatched starts with to ‘the Grotto’ checking where the geotechnical team emails for what might have were based. At the time happened that requires an David Jones was developing urgent response. contaminated land capabilities and I got involved through Next, there will be project him on projects like Thurrock reports to write, check or MSA. After a couple of years review; technical queries to rotation around the various respond to, proposals to write, departments, designing discussions with Clients, shopping centres, (The contractors, CGL project Wellington Centre in Aldershot managers and engineers; and The Peacocks in Woking internal / external or site all have a bit of me in them!), meetings, planning of training post tensioned bridges, grain and compliance audits and conveyors, David invited me actions... and not forgetting back to work on contaminated finding time to catch up with land projects and as they say.... the great bunch of people who the rest is history. work at CGL!

“

Are there any projects which you’re particularly proud to have been a part of?

All of them really, as I hope I give all my projects 100% to get the best answer, but if I have to pick, it would be the Blue Print industrial Estate in Portsmouth. This was an early project with BG Properties Gasworks. More recently, the ground investigation at the old New Scotland Yard which had some serious logistical challenges and currently the remediation of Royal Wharf with Ballymore which has transformed for the better that stretch of waterfront.

What are the most challenging aspects of your role?

Juggling time and energy to support staff and projects on the technical side whilst developing new works and delivering quality results and advice. Keeping a life/work balance is important.

What AGS Working Group(s) are you a Member of and what are your current focuses?

Loss Prevention Working Group; there are lots of things

on the go, from looking at the impacts of contract clauses, poor wording in reports, disputes and events and trying to use a crystal ball to see what commercial issues may be arising in the future.

What do you enjoy most about being an AGS Member?

Being part of a group and network of intelligent interesting professional people who are passionate enough about what they do to want to share their experience. It is also a great forum to exchange ideas and thoughts.

What do you find beneficial about being an AGS Member?

Following on from the previous answer, the library of information and guidance is amazing and it is easy to forget how comprehensive and accessible it is. Although, I haven’t used them very much, knowing that the ‘helplines’ are there and the knowledge/ experience of the people behind them, is re-assuring.

the AGS provides a central ‘hub’ and place of reference, where ideas, latest thinking and best practice can be collated and disseminated and provides a single point of contact enabling the ground engineering industry to present a coherent and consistent face to the construction and land management sectors.

What changes would you like to see implemented in the geotechnical industry?

Recognition of the value and importance of what ground engineering, (be it geotechnical or geoenvironmental), brings to construction projects. We so often see that the lowest price is the deciding factor, when high quality data and advice is what is needed to get the right and most economic answer first time.

John Burland was so right when he said you would pay for a ground investigation whether you have one or not, but the flexibility and benefits of having quality up front information, with some Why do you feel the AGS is exceptions, doesn’t seem to important to the industry? be a message that gets much further than the ground The industry has such a variety engineering specialists. of skills and technologies that June / July 2020

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Standards Update

June 2020

RECENTLY PUBLIS STANDARD

SUBJECT / TEST

BS 5930:2015 + A1:2020

Code of practice for ground investigations

BS 10176:2020

Taking soil samples for determination of volatile organic compounds (VOCs) - Specification

BS ISO 11277:2020

Soil quality – Determination of particle size distribution in mineral soil material – Method by sieving and sedimentation

BS EN ISO 18674 -3:2017 + A1:2020

Geotechnical investigation and testing – Geotechnical monitoring by field instruments – Pa Measurement of displacements across a line: Inclinometers

BS ISO 22190:2020

Soil quality – Use of extracts for the assessment of bioavailability of trace elements in soils

SELECTED INTERNATIONAL & EUROPEAN STANDAR STANDARD

SUBJECT / TEST

BS ISO DIS 11063

Soil quality - Direct extraction of soil DNA

ISO DIS 12404

Soil & Waste - Selection & application of analytical screening methods for on-site use

BS ISO 16751

Soil quality - Environmental availability of non-polar organic compounds – Determination

potentially bioavailable fraction and the non-bioavailable fraction using a strong adsorbent complexing agent ISO WD 18400-301

Soil quality – Sampling – Part 301: Sampling and measuring of volatiles in soil quality field investigations

BS EN ISO 21365

Soil quality - Conceptual site models for potentially contaminated sites

EN ISO NP 24212

Soil quality - Remediation techniques applied at contaminated sites

SELECTED INTERNATIONAL & EUROPEAN “GE STANDARD

SUBJECT / TEST

EN 1997-1

Eurocode 7 - Geotechnical design – General Rules

EN 1997-2

Eurocode 7 - Geotechnical design – Ground properties

EN 1997-3

Eurocode 7 - Geotechnical design – Geotechnical structures

BS EN ISO 18674-4

Geotechnical investigation and testing – Geotechnical monitoring by field instrumentation – 4: Measurement of pore water pressure: Piezometers

ISO CD 24283-1

Geotechnical investigation and testing – Qualification criteria and assessment – Part 1: Qua technician

ISO CD 24283-2

Geotechnical investigation and testing – Qualification criteria and assessment – Part 2:

ISO CD 24283-3

Geotechnical investigation and testing – Qualification criteria and assessment – Part 3: Qua

Responsible expert enterprise BS EN ISO 22475-1

Geotechnical investigation and testing – Sampling of soil, rock and groundwater – Part 1 – Technical principles

BS ISO DIS 22476-9

Ground investigation and testing – Field testing –Part 9: Field vane test (FVT and FVT-F)

PAS 128 (revision)

Underground utility detection, verification and location - Specification

34

Magazine

SHED STANDARDS SUPERSEDED/WILL SUPERSEDE

STATUS

PUBLICATION DATE

BS 5930:2015

Published

June 2020

n

New standard

Published

June 2020

y

BS ISO 11277:2009

Published

April 2020

BS EN ISO 18674-3:2017

Published

May 2020

New standard

Published

April 2020

art 3

RDS ON SOIL & SITE ASSESSMENT - In preparation SUPERSEDED/WILL SUPERSEDE

STATUS

PUBLICATION DATE

BS EN ISO 11063:2013

Proceeding to FDIS

2020

BS EN ISO 12404: 2015

Awaiting decision

Comment period ended 4 May 2020

of the New standard

Proceeding to publication

2020

New standard

Project initiated

2022

New Standard

ISO 21365 published October 2019, EN voting ended 30

2020

t or

April 2020 New standard

Project initiated

2022

EOTECHNICAL” STANDARDS – In preparation SUPERSEDED/WILL SUPERSEDE

STATUS

PUBLICATION DATE

Will partially replace BS EN 1997-

Comment period for prEN ended 8 January 2020

2023

Will replace BS EN 1997-2: 2007

Comment period for prEN ended 8 January 2020

2023

Will partially replace BS EN 1997-

Comment period for prEN ended 8 January 2020

2023

– Part New Standard

FDIS being prepared

2020

alified

Comment period ended 21 January 2020.

2021

1: 2004 + A1: 2013

1: 2004

New standard ISO TS 22475-2:2006 (BS ISO 22475-2: 2011)

alified ISO TS 22475-3:2007 (BS ISO

Not approved to proceed as DIS. UK voted against approval.

2021

Future yet to be decided.

2021

BS EN ISO 22475-1:2006

FDIS launched 25 Feb, Comment period ended 7 April.

2020

New Standard

FDIS being prepared

2020

PAS 128: 2015

Public comment period ended 16 March

2020

22475-3: 2011)

June / July 2020

35

AGS Working Group Focus

Contaminated Land Overview across all areas to educate and guide individuals who are new to the field.

Vivien Dent, AGS Contaminated Land Working Group Leader, has provided an update from the Groups most recent meeting, which was held virtually on 28th April.

Here is an overview on the top topics which are currently in discussion:

AGS GUIDE TO ASBESTOS We’re currently in the final stages of reviewing the AGS Guide to Asbestos, and are close to completion. The guide will be published on the AGS website in due course.

GRADUATE KEY READING LIST The Contaminated Land Working Group have decided to create a key reading document.

This will be primarily aimed at graduates or those new to the industry, and will feature a reading list of key documents

36

Magazine

We’re keen to engage with graduates and early career professionals, so this working group task is specific for this new generation of geoenvironmentalists.

UKAS INSPECTION BODIES SURVEYING CONTAMINATED LAND FOR THE PRESENCE OF ASBESTOS UKAS plans to establish a pilot programme for the development of ISO/IEC 17020:2012 accreditation for the inspection of land for the presence of asbestos.

The AGS CLWG have concerns that the scheme has not considered broader land contamination issues and that people who are unqualified will attempt to do the role of a contaminated land engineer.

Whilst an asbestos surveyor might be qualified to look into asbestos, it’s unlikely that they’ll understand all documentation and the processes for all contaminants.

Naturally we don’t want there to be a situation where projects are required to have both an asbestos surveyor and a contaminated land surveyor.

This would be an additional project expense and create additional work and expense for the client.

WORKING OUTSIDE OF THE AGS The AGS Contaminated Land Working Group have many members who are involved in a range of different projects and working groups; SAGTA C4SL project, the National Brownfield Forum, SiLC, SoBRA and more.

This enables us to share new information within the Group but also relay the position of the AGS CLWG outside of the organisation.

We are always keen to welcome new members into the Contaminated Land Working Group and so for those interested in the governance of the AGS and wish to know how you can contribute to the CLWG, please contact the AGS Secretariat at ags@ags.org.uk.

How to become a Member of the AGS AGS Members all share a commitment to quality in the geotechnical and geoenvironmental industry. This has become widely recognised by clients, governmental bodies and other associations that touch issues to do with the ground.

We welcome both companies and individuals who want to be recognised for their quality of practice to join our growing membership of over 130 Members. We shape our industry, continually improve practice and collaborate on issues that affect us all; from clients, all the way through to the people who use the land and the buildings we help develop.

To become a Member of the AGS, please visit http://www.ags.org.uk/about/become-a-member and submit your application online. Please note that all membership applications are reviewed by the Membership Committee 6 weeks in advance of each quarterly Executive meeting.

The deadline for the next round of completed applications is Tuesday 18th August 2020.

AGS Chemical and Legal Helplines All Members of the Association of Geotechnical and Geoenvironmental Specialists are entitled to free chemical and contractual advice through the use of Loss Prevention Committee Members, Marquis & Lord and Beale & Co. For advice on chemical safety and best practice, Marquis & Lord will provide 30 minutes of free advice to all AGS Members.

Additionally, if you’re an AGS Member and are looking for legal advice, please contact Beale & Co and ask quote ‘AGS Helpline’ where the first 15 minutes of legal advice will be free of charge.

CHEMICAL SAFETY HELPLINE Marquis & Lord Tel: +44 (0) 121 288 2386 www.marquisandlord.com

LEGAL HELPLINE (Please quote Beale & Co ‘AGS Helpline’) Tel: +44 (0) 20 7469 0400 www.beale-law.com

Member Reporting Service for Industry Issues If you have any queries regarding AGS Data Format, there is a discussion forum on the AGS Data Format website, where queries can be posted and answered by the Data Format team.

If a Member has any issues with regard to Safety, Contaminated Land, Geotechnical, Instrumentation & Monitoring or Laboratories which you think the industry should be aware of please email ags@ags.org.uk, we will then forward your email to the relevant AGS Working Group.

Disclaimer These articles are the opinions of the authors and are not intended to be a complete or comprehensive statement of the law, nor do they constitute legal or specialist advice. They are intended only to highlight current issues from date of publication that may be of interest. Neither the writer, nor the AGS, assumes any responsibility for any loss that may arise from accessing, or reliance on the material and all liability is disclaimed accordingly. Professional advice should be taken before applying the content of the articles to particular circumstances.

June / July 2020

37

Advertising and Rates An online advertising campaign within the AGS Magazine will help to build and increase industry awareness of your company’s profile, initiatives and offerings.

The AGS can help build a package to suit your needs and budget; whether it’s a series of adverts across multiple issues, a combination of event sponsorship and advertising, or a single advertorial.

How to Advertise in the AGS Magazine The AGS Magazine is a free email publication which looks at a range of topical issues, insights and concerns, whilst publishing new guidance notes, working group activities and information on upcoming industry seminars.

With 10 issues each year, our subscribers include industry professionals such as practitioners, chartered specialists, senior decision makers and managing directors To receive a media pack or to discuss advertising rates, please contact Caroline Kratz on 0208 658 8212 or email ags@ags.org.uk

Adversiting Requirements

Advert Sizes and Rates

All adverts should be sent in a PDF, PNG, JPEG, TIFF, PSD (Photoshop) or EPS (Illustrator) format.

 FULL PAGE W: 210mm H: 297mm RATE: £400  HALF PAGE W: 210mm H: 145mm RATE: £250  QUARTER PAGE

company name address contact number email

W: 105mm H: 145mm RATE: £160

logo

 DIRECTORY Company name, address, contact number, email and one logo.

RATE: £50

38

All advertising artwork must be supplied in 114 dpi resolution.

Magazine

Artwork must be delivered to the AGS using the agreed artwork specification size listed left.

Artwork should be emailed to ags@ags.org. uk no later than 10 days prior to publication.

Directory

ADVERTISE HERE FOR JUST £50

ADVERTISE HERE FOR JUST £50

AGS Dates for Your Diary Upcoming AGS Events AGS Annual Conference

D E L Thursday 2nd April 2020 L Econtact ags@ags.org.uk C For more information, N CA National Motorcycle Museum, Birmingham

AGS Data Management Conference 2020

D E N O Wednesday 23rd September 2020 P T For more information, POS contact ags@ags.org.uk National Motorcycle Museum, Birmingham

AGS Laboratories, Instrumentation & Monitoring Conference 2020

D E N Hamilton House, Euston, O London P T2020 S Wednesday 15th July O P

For more information, contact ags@ags.org.uk June / July 2020

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