Article

An Insight into the SiLC Exam

- by
Tags: Featured SiLC

If you have ever considered applying to be a Specialist in Land Condition (SiLC) and wondered what the process is like, this may help you. We asked some people who have recently become SiLC what their thoughts on the process.

Motivation for becoming a SiLC is often driven by personal desire, but support and encouragement from employers can really help. Aspirations to achieve the next obvious step in career development and reassure clients and regulators of competence when trying to negotiate agreement on a tricky site were big personal drivers. In my experience and from talking to others, where employers do not actively encourage professional accreditations from early years, SiLC uptake is lower within an organisation. There are clients and regulators who require demonstration of competence, such as SiLC, to work on their projects.

Looking back over their SiLC application process, candidates consider it has given them increased confidence in their own abilities and instilled some new behaviours that help them do a better job going forward. For instance, they have continued the rigour in researching source documents for actual legal definitions or specific wording in guidance rather than relying on memory or text within a previously written report. During exam research one candidate set up a series of weblinks to key documents which they now consult easily and regularly as part of their job. Another candidate really enjoyed going back to some of the source legislation that they might not have consulted for a while and reading minutes from some of the contaminated land forums which exist. On receiving the exam questions, candidates tend to be aware of the main topics and knew where to start and where further research was required to add detail to their answers. Some struggled with providing an executive style summary of data within a word count but recognise this is a key skill for presenting technical information to clients. It is always best to write the summary and then go back through it, perhaps several times, to ensure that all the salient points are covered and that the envisaged client would get an appropriate understanding of the site, based on the information provided, and also to check that words are not used up unnecessarily where a more concise use of words would leave some words to enable the adding of more information provided that it is included in the supplied report extracts etc.

Many said that the SiLC Induction Day was beneficial, making people feel “I’m ready for this” or “I can achieve this” and de-busting some of the myths about how difficult it is to become a SiLC. It highlighted the need to consider what being a specialist within your own field and experience means. You are not expected to be an expert but you are expected to employ rigorous questioning and checking of facts and research. The pass rate is higher for those who attend the Induction Day compared to those who don’t. Some consultancies have hosted Induction Days for a number of their staff at one time.

The interview was generally found to be “challenging but fair and friendly”. Those candidates who had reviewed their exam submissions prior to the interview and acknowledged where they did not know an answer but could explain what they would do to find out were typically more successful.

Candidates should not underestimate the time required to complete the exam and this can be the reason why some candidates fail. However, those who have been through the process and come out as a SiLC have found that it has given them increased confidence and often changes their ways of working for the better. It is also easy CPD for the year. All say that having done it that they feel it was a worthwhile and rewarding experience.

As a SiLC we can help raise standards within our industry by encouraging our employers to support and promote professional accreditation and raise awareness with potential clients and regulators of systems in place to demonstrate competence.

Further information about SiLC can be found on the SiLC website.

Article provided by Louise Beale, Technical Director at SLR.

Article

Q&A with Zita Mansi

- by
Tags: Featured


Full Name: Zita Mansi
Job Title: Senior Associate
Company: Beale & Co

Zita has specialised in environmental and construction professional indemnity law since May 2002.  Her construction practice includes the defence of claims against engineers, architects and other construction consultants and bringing claims for contribution and counterclaims for fees where necessary.

Her environmental practice includes: defence of claims against construction consultants arising out of contaminated land issues; defending claims in negligence, public or private nuisance for losses attributable to environmental factors (contamination, odours, noise, vibration, dust, flooding etc); responding to enforcement actions and investigations undertaken by various regulators following environmental incidents (including advising before and during interviews under caution, submissions to the regulator regarding level of harm caused, and establishing whether the regulator has followed its own internal policies and procedures); defending environmental prosecutions and related third party claims.

Zita is responsible for the day-to-day conduct of litigated and non-litigated disputes and frequently acts in multi-party disputes in the TCC, in mediations and other forms of ADR. She also acts in regulatory matters in a construction context, advising clients in response to HSE investigations and defending prosecutions.

What or who inspired you to become a lawyer in the construction industry?
During my training contract to become a solicitor I did a seat in the construction team of the firm I was with. I really enjoyed the complexity of construction projects and every case is so different and offers a new challenge. There are also many technical as well as legal issues to understand too. From early on I was involved in defending claims brought by developers against ground engineers. I developed a special interest in these types of claims and helping engineers to put in place simple measures to avoid them.

What does a typical day entail?
Every day is different of course but a typical day would involve reviewing documents, attending meetings and / or phone calls with clients. Dealing with ad hoc queries. We also manage the AGS Legal Helpline so I quite often will deal with calls from that.

Are there any cases which you’re particularly proud to have advised on?
I often defend prosecutions brought by the Environment Agency and on many occasions we have persuaded the Agency not to prosecute our client which is extremely satisfying.

What are the most challenging aspects of your role?
I will often have multiple deadlines running at the same time so managing these, my time and multi-tasking between them can be difficult. It can also be difficult to switch off when I’m not in the office from certain cases that are particularly challenging.

What AGS Working Group are you a Member of and what are your current focuses?
I am a member of the Loss Prevention Working Group, which focusses on commercial risks faced by members and how to reduce them. One of our objectives is to get across the message that there are simple things members can do to reduce their exposure to claims. The group held a seminar in London recently on ‘Commercial Risks’ which I was lucky enough to speak at, covering collateral warranties, reliance and limiting liability. We are hoping to re-run the seminar in Manchester later in January 2020.

What do you most enjoy about being an AGS affiliate and why is it beneficial?
Being involved in the AGS gives members a great opportunity to share their knowledge and hear from other members and learn from them. I find this incredibly beneficial in my role as a lawyer and also on the Loss Prevention Working group. Understanding the reality of what the members work involves and the practical issues they face means that as a lawyer I can make my advice more relevant.

Why do you feel the AGS is important to the industry?
The AGS is an important focal point and repository for know-how tailored to this particular industry. It helps to maintain standards and their work can influence other industry bodies.

What changes would you like to see implemented in the geotechnical industry?
I would like to see an acceptance by employers and clients that it is reasonable for engineers and contractors to limit their liability. Unlimited liability benefits no-one and only puts the consultant / contractor at risk of insolvency.

Article Loss Prevention

AGS Commercial Risks and How to Manage Them Conference

- by
Tags: Featured

The AGS held it’s first Commercial Risks and How to Manage Them Conference on 3rd July 2019 at the Chartered Accountants Hall in Moorgate Place London, which was sponsored by BAM Ritchies, Bridgeway Consulting, Envirolab, Fugro, Geo Integrity, NHBC, Structural Soils, Socotec and Tensar. The event was a sell out and following a very nice lunch and opportunity to meet some of the sponsors, a tightly packed schedule with expert speakers talking on various pertinent topics was laid on for delegates.

Zita Mansi (Beale & Company) kicked off with detailing  what to look for in terms of appointment, such as limiting assignments and 3rd party rights, limiting liability with a financial cap, ideally in the aggregate (noting that this is different to the limit on PI insurance),  and excluding indirect/ consequential liabilities. Further advice followed on controlling additional contracts such as Collateral Warranties which multiply liabilities and reassignments, which transfer liabilities. Both should reflect the original contract and avoid extending the scope and duration of liabilities. Such additional risks should be priced appropriately.

Hugh Mallett (BuroHappold and AGS Loss Prevention Working Group Leader) spoke on the importance of defining the scope of works and objectives clearly and where something apparently wrong appears in the scope, this must be clarified and not ignored to avoid potential future disputes.  Even, and especially, when the client is well known with a good working relationship. He recommended use of authoritative definitions and report contents where possible, a clear agreed set of terms and conditions and checks / caveats on the quality of 3rd party data.  Beware ‘cheap and quick’ reports which impose the same liabilities as a full assessment.  AGS LPA 69 provides appropriate advice and guidance.

Stephen Hargreaves (Griffiths and Armour) provided a number of case studies based on insurance claims. He explained that geotechnical works are considered high risk because of the risks of ‘unknowns’ and the associated high value claims. The geotechnical engineer can unwittingly become part of a dispute even when they have discharged their duties under the contract.  Reiterating and expanding on Hugh’s message, the advice was to beware Client’s making assumptions on the scope and objectives.  Further there is onus on the engineer to reference limitations, qualifications and assumptions relating to advice given to avoid misuse and misinterpretation and an unintended extended duty of care. Generally claims often 0000000 occurred where there was an interface between various non contracted parties and lack of communication.  The advice was to maintain an ‘eyes wide open’ policy.

Russell Jones (Golder Associates) brought forward the ‘battle of the forms’, i.e. which form of contract applies when a client offers on form and the consultant/ contractor offers an alternative. The ‘alternative’ is still an offer or counteroffer, until acceptance is in place. In a nutshell, the contract that has ‘acceptance’ will be deemed the relevant document, which is usually the ‘last shot wins ‘approach, i.e. the last counteroffer on the table. However, this can be counteracted by action, such as the works starting which can be deemed as acceptance of the offered contract. The key is negotiation, clarity and …where possible, issue the last offer of terms!

Adam Gombocz (NHBC) moved away from direct contractual issues to talk about how the NHBC ‘Buildmark’ warranty provide insurance for building works, but will ONLY be granted when adequate and appropriate investigation, assessment and design has been completed to the satisfaction of the NHBC technical team. He described a number of shocking (and expensive!) case studies. Problems typically relate to lack of site investigation, soft soils, settlement, raised levels, groundwater and/or deep fill, with most issues arising on site where ground levels are raised and assessment/ design does not take account of this.  Guidance on NHBC requirements regarding Land Quality is included in Chapter 4.1 of the NHBC guidance.

Rachel Griffiths (Fugro) explained the ‘duty of care’ required in providing services or goods.  Goods fall under a ‘fit for purpose’ requirement of the Sale of Goods Act. Provision of services falls under a requirement for ‘reasonable skill and care’ under the Supply of Goods and Services Act. These are different and consultants giving advice or providing designs should make sure that the contract is specific as to the required duty of care to avoid defaults and misunderstandings. This should also be made clear in reports. Similarly, beware wording in contracts that ‘warrants….guarantees….. ensures….’ which implies a standard of services over and above reasonable skill and care and increases liabilities and may not be covered by PI insurance.

As the final speaker, on a non contractual topic, Jonathan Atkinson (Environment Agency) raised the subject of landfill tax being payable on illegally deposited waste, be that on an unlicensed landfill or unpermitted deposit on a construction site. Non complaint disposed materials attract the higher rates of landfill tax and HMRC who are now working with the EA have the option to add a further penalty of 100% landfill tax. This is in addition to any prosecution and associated fines.  It is also retrospective. Those at risk are anyone involved in wrongful deposition of waste, such as advisors, brokers, hauliers, landowners, waste producers, as the liability is ‘joint and several’. The legislation equally applies to construction wastes including incorrect use or abuse of waste exemptions or the CL:AIRE DOWCOP . Therefore, to protect against prosecution evidence is required to show that all reasonable steps have been taken to ensure that disposal at an unauthorised site doesn’t happen. This relates to making sure that material isn’t waste and if it is, that it is handled, disposed or re-used  in accordance with the relevant legislation and that records are available as proof, such a checks on material being disposed to the correct site or production of a verification report.

All attendees were given food for thought. For some it was maybe a ‘wake up’ call or reminder that simply ‘doing the job’ is not enough.

The AGS website has numerous documents and up to date commercial guidance, freely available to members and the Legal Helpline offers members 15 mins of free advice  from Beale and Co, if needed.

Presentations from the Conference with approval from speakers can be viewed on the AGS website.

Article provided by Jo Strange, Technical Director at CGL and Chair of the AGS Commercial Risks Conference.

Article Report Laboratories

AGS Laboratories Working Group Update

- by
Tags: Featured

Mark Beastall of Socotec, the recently elected new leader of the Laboratories Working Group, has provided an update on the top issues the Laboratories Working Group discussed at a recent meeting which took place in May 2019.

Validation of a suitable calibration procedure for the Filter Paper used in the BRE4/93 Soil Suction Test
Dimitris Xirouchakis has written a new procedure for the calibration of Filter Papers. This method has been sent to the members of the Laboratories Working Group to trial at their laboratories. The group are looking to discuss the outcomes of trialling this method at their next meeting.

The transition from BS1377 to BS EN17892 & BS EN 13286 (Earthworks testing)
Although a number of laboratories have now been granted accreditation to the BS EN methods, the industry outside of the laboratories seems very slow in the take up; i.e. not appearing in specification / testing instruction. The Laboratories Working Group are concerned about this and are trying to push out information to industry groups that BS1377 methods in their current form will soon be obsolete.

Increasing member participation
The core members of the Laboratories Working Group are all of the opinion that the participant numbers are far too low and attendance at the meetings rarely reaches double figures. It is essential for the future of this Working Group that numbers increase and that a broader (not just labs) attend these meetings to ensure the group are capturing the wider Geo-Environmental sector. The Laboratories Working Group are looking for new participants from AGS members who have a direct interest and influence on specifying / scheduling testing as well as AGS members with laboratories. The Laboratories Working Group are concerned that they are not getting a full picture of issues that AGS members are coming across and as such points of discussion and content of meetings can be limited.

If you do wish to join the AGS Laboratories Working Group, please contact the AGS Secretariat at ags@ags.org.uk.

Article Safety

Trial Pitting – Still Fit for Purpose?

- by
Tags: Featured

Trial pitting and trial trenching have long been a popular investigation tool within the geotechnical and geo-environmental industry. Trial pits and trial trenches are commonly specified in both geotechnical and geo-environmental investigations and are often a preferred investigative method to enable a rapid check of the condition of the ground. They permit examination of both horizontal and vertical faces exposed as the pit is advanced and also enable the collection of a wide variety of sample sizes and types. Trial pitting and trenching is commonly undertaken using a machine excavator, whether this be a backhoe excavator or a tracked 360 machine. For shallower excavations, or where trenches are required to provide more detailed interpretation of the stratigraphy or underground service identification and mapping, these are often undertaken by hand with or without machine assistance. Vac-Ex technology has also been used by the industry to excavate trial pits and trenches.

Trial pitting is seen as an economically advantageous investigation tool which enables a fair spread of exploratory points to be undertaken within a typical working day. In addition, trial pitting facilitates a wide variety of in-situ tests, for example Hand Shear Vanes, California Bearing Ratio (CBR) tests, Plate Load tests and Infiltration tests in accordance with Building Research Establishment (BRE) Digest 365 Publication (2016).

With a better awareness of health and safety risk within our industry over the past decade or so should we not, however, ask the question whether trial pitting is still fit for purpose and therefore should we strive for an alternative method?

Health & Safety law often uses the term, “so far as is reasonably practicable (SFARP)” forming the basis of any risk-based activity and as such must be used as a decision tool on the risk against the cost and availability of technology to control it.  The HSE, in investigation and prosecution, make a computation in which the quantum of risk is placed on one scale and compared with the sacrifice involved in the measures necessary for averting the risk (whether in money, time or trouble) on the other scale.  The legal test would be that measures which are disproportionate (or grossly disproportionate) would not be SFARP.

All trial pitting activities including site preparation, excavation, sampling, logging and backfilling must be planned and a suitable and sufficient site-specific risk assessment made, contributing then to a method statement. However, consider this: with the Work at Height Regulations (2005), any excavation which has the potential for a person to fall is classed as working from height and, therefore, requires measures to be put in place in accordance with a specified hierarchy (while considering “SFARP”) to comply. Whilst injury can be caused from a fall from any height, a trial pit which is excavated to depths often in excess of 3m can pose a significant risk of injury should an operative fall into the excavation.

Additionally, the Construction Design and Management (CDM) Regulations (2015) were amended and now identify ground investigation as an integral part of the construction activities. Trial pitting as an activity is covered under Regulation 22 (Part 2) which states that “Suitable and sufficient steps must be taken to prevent any person, work equipment, or any accumulation of material from falling into any excavation”.

Furthermore, Regulation 22 (Part 1) of the CDM Regulation states that “All practicable steps must be taken to prevent danger to any person, including, where necessary, the provision of supports or battering, to ensure that; no excavation or part of an excavation collapses; no material forming the walls or roof of, or adjacent to, any excavation is dislodged or falls; and no person is buried or trapped in an excavation by material which is dislodged or falls”.

Therefore, all excavations require an assessment to be made of the stability of the excavation prior to commencing the dig and during the dig. These risk assessments should consider factors such as influence of the excavation method, ground conditions, buried services, obstructions, groundwater level, water strikes, contamination etc. An initial risk assessment can be produced to reflect the general approach but inevitably the trial pitting supervisor/logger will need to carry out dynamic, sometimes called “point of work”, risk assessments and where these necessitate or identify significant changes to the risk or methodology it should be documented.

However, as trial pitting work is often undertaken by graduates or technicians, can employers be sure that these individuals possess the required knowledge, training and experience to meet sufficient competency requirements or have the ability to make these assessments and informed decisions?

When detailed logging (i.e. service identification, detailed fabric logging, scan lines or assessment of slip planes) is required, due consideration should be taken to the necessity of entering the trial pit/trench. Where the designer determines that entry is essential, the Contractor must ensure that the excavations are sufficiently shored or the excavation sides battered back or benched to reduce the height of exposed material and potential collapse. Due consideration should also be taken by the Client to allow sufficient time and resources (money) to develop this safe system of work, to carry out any additional training requirements and for the actual work. In addition, these type of trial pits should be located to provide sufficient working room for the plant which will be required for the installation and maintenance of the support system and spoil. As these types of works may be of a longer duration than typical trial pits, physical barriers such as fencing may be required which adds additional costs and time.

When trial pits are part of a more typical ground investigation and require standard logging, in-situ testing and sampling the designer and contractor should consider carefully whether any entry is required whatever the depth. The AGS promotes an approach which does not require entry and therefore, the risk of injury through collapse and subsequent burial is reduced. However, this does not eliminate totally the risk of working at height.

With trial pitting seen as a relatively quick and cost-effective method of ground investigation, the use of edge protection and trench support can be viewed as unrealistically costly and time consuming to install. Compliance with the hierarchy of controls within the Work at Height regulations might suggest to some employers that installation of edge protection or a suitable fall arrest system or other safe system of work, should be mandatory for all excavations. However, the main advantage of trial pitting is to provide a quick and easy way to view the stratigraphy and close up inspection of the pit is necessary to obtain the desired results. Judgements on the required controls under the Work at Height regulations are however to be determined “SFARP”.

The current AGS Guidance on safe excavation of trial pits suggests a number of control measures such as the supervisor/logger should approach and stand at the opposite narrow end of the open pit to the machine, , arisings should be placed a minimum of one metre from the pit edge, and other controls. However, the industry, and associated industries who undertake not dissimilar construction activities, can still not agree on the approach to controlling the risk of working at height when trial pitting or even whether it is a significant risk in the first place.

The principal arguments for the requirement to approach open pits is to observe the formation of the ground and groundwater in situ, accurately measure stratum boundaries, water strikes, final depth and to take photographs. The industry could for example re-evaluate the necessity for photographs and the way they are taken, and whether they are used as anything else but proof the pit was dug. The question could also be asked as to ‘how accurate is accurate’ with respect to depths and is there a safer way to obtain this information. Some excavators can now determine depth of dig whilst excavating and perhaps providing depth markers on the excavator arm may be another alternative.

Figure 1 – Typical example of a machine excavated trial pit where the pit is logged from samples only

Employers must also consider the risk of injury from contact with plant and machinery. It is essential that the supervisor maintains good communication (both verbally and using agreed hand signals) with the machine operator at all times. Supervisors should be aware of the danger areas (red and amber zones) around the excavation and always stand in the yellow zone to maintain a clear line of sight.

Figure 2 – An example of a safe working zone for mechanical excavation using a 3CX or 360 machine

It is not uncommon that the supervisor (often a graduate and in some cases with limited years of experience) will take on responsibilities for both the H&S and the technical goals of the trial pit investigation. In effect, they take on a role of supervisor, logger and banksman. In the construction industry, banksmen are operatives specifically trained to direct vehicle movement on or around site. How common is it that graduates or even experienced engineers are specifically trained in the role of a Banksman (or vehicle marshal), but are expected to fulfil such a role when directing plant and machinery around site. Therefore, the employer should provide training to allow the individual to carry out this role. This could be delivered through a formal Banksman course or might be better delivered as task specific in-house training which should include all aspects of safe trial pitting to help create competent people who can dynamically risk assess excavations.

But is trial pitting really or inherently a high-risk activity? Excavations are typically left open for only a very limited length of time and are backfilled as soon as the pit is completed in comparison to most construction industry excavations. In addition, there are no clear statistics from the HSE on injuries or fatalities from falls associated with trial pitting. These do occur in the wider construction industry, generally as a consequence of a collapse of the excavation which has been open for some length of time. As an industry we are all aware of the fatality to a Geologist in September 2008, however, statistics of injuries, accidents or near misses are not widely known and are often only communicated internally with site staff and not shared to the wider ground investigation community.

As an industry we must strive to continually improve the safety culture within ground investigation and trial pitting offers us all a chance to either look at current and future innovations to reduce the risk or find safer alternatives. There is a concern that if the industry does not obtain consensus that others may develop approaches which the industry may not find palatable both practically and commercially.

The current AGS document looks to provide practical guidance on trial pitting considering the current H&S guidance available, however, the Designer always has the choice to replace trial pits with boreholes or dynamic sampling holes which would, in many cases, provide similar design data.

The question remains, is trial pitting fit for purpose and the AGS would welcome views from the industry and will be sending out a short questionnaire to determine current industry practice and thoughts.

Article contributed by AGS Safety Working Group

Principal Authors – Adam Latimer, Ian Farmer Associates; Steve Everton, Jacobs and Julian Lovell, Equipe Group

 

 

News

AGS Magazine: June/July 2019

- by
Tags: Featured

The Association of Geotechnical and Geoenvironmental Specialists are pleased to announce the June/July 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 month’s issue including;

Safety in Mind – A conference from the AGS Health & Safety Working Group – Page 8
Trial Pitting – Still Fit for Purpose? – Page 10
Asbestos Risk – The need for practical industry guidance for ground investigation – Page 16
AGS Review and Position Statement: Cover Systems for Land Regeneration – Page 20
Q&A with Geraint Williams of ALS – Page 22
Working Group Focus: Contaminated Land – Page 25
Standards Update: June 2019 – Page 26

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 Contaminated Land

AGS Review and Position Statement – Cover Systems for Land Regeneration

- by
Tags: Featured

Thickness Design of Cover Systems for Contaminated Land: BRE/AGS/NHBC: 2004

Starting in 2017, the AGS Contaminated Land Working Group (AGS CLWG) undertook a review of the 2004 BRE/AGS cover systems document to determine:

a) if it was still fit for purpose given current regulatory practice and guidance,
b) what awareness of it there was within the industry and with regulators,
c) how much it was being used and accepted by regulators as evidence,
d) what was current general practice,
e) if the document and software required updating,
f) if it might be applicable or adaptable for sites with trace levels of asbestos.

As part of this review, several questionnaires were forwarded to regulators and private industry practitioners and awareness was raised at several industry events as well as within the various AGS working groups. In conclusion the results of this review can be summarised as follows:

The document is still considered technically fit for purpose, though the fact that it specifically excludes considerations of the emplacement of break layers and water table movements somewhat limits its applicability under current practice at present. That it has not been updated or reviewed since it was published in 2004, and whilst still available is quite expensive, also probably somewhat limits its use by regulators or practitioners.

The document has suffered from a general change in practice since it was first published and perhaps more importantly a change in the way waste is currently defined and perceived in practice during developments. This is (in part) due to regulatory waste changes and interpretations as well as changes in CDM. This is seen as being two-fold in practice, firstly in that the placement of materials from off-site as cover can now potentially be considered a de-facto waste action. Secondly, the technical mixing of potentially contaminated materials in situ with uncontaminated material is contraindicated by current guidance, being seen as potentially “diluting” the contaminants in the underlying materials. This paradox, since the underlying material is probably not technically a waste per se, has certainly in part limited the uptake of this methodology by both practitioners and regulators.

In addition, the responses clearly indicated that many practitioners and regulators were unaware of this document and its potential uses, possibly due to institutional loss of knowledge and experience over time since publication, as well as changes in general contaminated land and waste practice. In addition, it would appear that not many practitioners were presenting such evidence or systems on behalf of clients or developers, probably for essentially the same reasons.

It was noted in the responses that many regulators now default to generic requirements for cover systems. The usual default being 600mm or “Two Spades depth” and usually overlying a break layer. This later element was seen by most regulators and some practitioners as being more effective, acceptable and risk averse in that a break layer provides added security, i.e. by providing an obvious pathway linkage break. Such actions also avoid having to consider potential mixing issues and therefore complies more justifiably with current contaminated land exposure models, remediation practice and guidance by “removing” a pathway rather than just mitigating it.

Unfortunately, this trend may not be truly more sustainable or cost effective as the associated costs and materials used in providing break layers are not always going to be as sustainable as not doing so or accepting lesser depths of cover. Practitioners may therefore logically be taking this lead from the regulators and therefore not considering using the document and methodology on behalf of their clients, even if they are aware of it. This is because the associated costs of justification and arguing the case in a scientific and robust manner may be more than simply accepting emplacement of a break layer and provision of the full cover depth required by the regulator.

On the basis of the above findings, it is considered that current policy and lack of awareness make this a rarely used methodology in current practice. The document and software could be updated relatively easily to make them more user friendly as the general underlying science is still considered current and relevant. However, the general lack of enthusiasm noted for its use in light of the issues highlighted above (especially the general regulatory trend towards the use of generic depths and break layers) probably do not justify the associated costs of doing so at this time.

In conclusion, the basic science is still considered very sound, and the document would benefit from a wider awareness in the community and amongst regulators were it not for the tendency towards the more risk averse inclusion of break layers and standard depths. This has perhaps been a quite reasonable response to changes in regulatory frameworks since the document and software were first produced in 2004 and also probably reflect a general loss of institutional knowledge regarding the methodology over time.

There remains a potential for the methodology to be resurrected and updated for application in solid contaminants such as trace asbestos in soils, though sadly the supporting science is not currently available to justify such works in other than a speculative way.

On this basis the position of the AGS is that updating of this document is probably not sustainable or cost effective at present, but may be so in the future if:
1. Regulatory attitudes change,
2. Practitioners feel it still has utility in certain circumstances,
3. It has greater awareness within the community,
4. It can be adapted to meet additional and scientifically justifiable uses.

Article contributed by AGS Contaminated Land Working Group

Article

Q&A with Geraint Williams

- by
Tags: Featured

Full Name: Geraint Williams
Job Title: Associate
Company: ALS

Geraint has over 20 years’ professional experience and is technical lead for his company. He is a member of the AGS contaminated land and laboratories working group. He serves on the Executive Committee of the Society of Brownfield Risk Assessment (SoBRA) and participates in specialist groups including SoBRA’s vapour intrusion subgroup as well as chairing SoBRA’s Technical Panel. Geraint also serves on EH/4, the British Standards committee on soil quality and is chair of a drafting panel for a new standard on sampling soil for determination of volatile organic compounds.

What or who inspired you to join the geotechnical industry?
My father inspired me to be involved in our industry. I remember travelling to nearby Wirral where he pointed out interesting geological features including the ‘Red Rocks’ at Hoylake.

What does a typical day entail?
I spend lots of time supporting my teams, through technical review, dealing with clients’ challenges and troubleshooting when issues inevitably arise. Training and mentoring colleagues is important and also the most rewarding aspect of my job.

Are there any projects which you’re particularly proud to have been a part of?
I spent the formative years of my career carrying out intrusive investigation work for McAlpine on a major gas pipeline project in the North West which was an excellent grounding for anyone starting out in our industry. I’ve been fortunate enough to be involved in the largest land contamination projects in the UK.

I’ve been involved in projects in the Occupied Palestinian Territories, Afghanistan, Kuwait, Ivory Coast, and Nigeria. I was in Iraq recently training those who are managing the investigation and remediation of sites that experienced widespread destruction from sabotage and looting by Islamic State. The impacts of war in eastern Mosul are so extensive that much of the old city has essentially been destroyed. It is a privilege to be part of reconstruction efforts in conflict affected areas of the world.

What are the most challenging aspects of your role?
Being away from my family – I spent a month in West Africa when my daughter was first born. She is now eight so probably won’t notice if I spent six months away from home!

What AGS Working Group(s) are you a Member of and what are your current focuses?
I’m a member of the Contaminated Land Working Group – we have recently produced practitioner guidance on waste classification for soils, description of anthropogenic materials and environmental sampling.

What do you enjoy most about being an AGS Member?
I genuinely look forward to every meeting as it provides an opportunity to discuss matters that directly affect our industry. It’s a forum for knowledge sharing and promoting best practice. I most enjoy the technical aspects of our meetings and the collaborative way we work together to overcome common issues and challenges.

What do you find beneficial about being an AGS Member?
The AGS is the only organisation representing both the interests of the geotechnical and geoenvironmental sectors. It’s beneficial how different working groups come together to tackle issues – asbestos is a good example of Contaminated Land, Labs and Safety Working groups co-ordinating their efforts to each have input into what will become pragmatic guidance.

Why do you feel the AGS is important to the industry?
AGS provides its members with a real voice within industry – we are active on the National Brownfield Forum, we are represented on the Phase 2 Category 4 Screening Level Project and are involved in updating the Guiding Principles; our membership includes the Environment Agency and the National House Building Council. We probably don’t appreciate how respected and influential the AGS actually is. I suspect this will only increase as focus is shifting more towards industry-led guidance.

What changes would you like to see implemented in the geotechnical industry?
Like most of us, I’d like to see government implement a truly brownfield first policy. Our sector is worth £1 billion a year and employs almost 10,000 people. The housing crisis is one of the UK’s greatest challenges and brownfield development is key to solving it. No surprise that AGS is at the forefront of highlighting these challenges and making positive steps to address them. If you haven’t seen it, read the article ‘Unlocking complex brownfield sites’ in a previous edition of this magazine.

Article Report Contaminated Land

AGS Contaminated Land Working Group Update

- by
Tags: Featured

Vivien Dent of RSK, the leader of the Contaminated Land Working Group, has provided an update on the top issues the Contaminated Land Working Group discussed in their recent meeting which took place in May 2019.

Updating the AGS Asbestos in Ground Investigation Guidance
This document was issued as interim guidance in February 2013. Since this time, there have been several publications and guidance documents published. The guidance is therefore possibly out of date and is being revised. The aim of the guidance is for people to know how to work safely when they encounter asbestos. The AGS Asbestos in Ground Investigation Guidance is currently in final draft and is being peer reviewed by the AGS Contaminated Land WG, along with the AGS Safety WG and AGS Laboratories WG.

AGS Guidelines to Good Practice in Geoenvironmental Ground Investigation
An opinion piece by Chris Swainston of Soils Limited on AGS Guidelines to Ground Practice in Geoenvironmental Ground Investigation was featured in the May 2019 issue of the AGS Magazine and can be viewed on the AGS website. The Contaminated Land WG are considering the possibility of creating a ‘road map’ of documents. The AGS aim to promote good practice – as Chris mentioned in his article – if you stacked the relevant documents on top of each other, the guidance alone would probably reach to your waist. As there is so much information out there – how do you know what is relevant? It is important that AGS members know which guidance to follow and where to find the guidance.

ERES Code Review
A working group has been established to review ERES Codes. The ERES Codes are being reviewed as it is important to have consistent data. For example, so there are not two or more codes for the same determinant.

Next CLWG Meeting
In their next meeting, which is taking place in July, the Contaminated Land Working Group will be looking at the Environment Agency’s online guidance; Land Contamination: Risk Management (LCRM) which is an update to the Model Procedures for the Management of Land Contamination (CLR11), with the aim of providing feedback to the Environment Agency on behalf of the AGS.
Feedback on issues

The Contaminated Land Working Group would like AGS members to feedback to the group about any issues they are struggling with and if there are any issues which they would like to group to investigate. If you do have any issues for the Contaminated Land Working Group to discuss, please email ags@ags.org.uk.

Article

Sampling Soils for Determination of VOCs

- by
Tags: Featured

The Draft for Public Comment (DPC) of BS 10176: Taking soil samples for determination of volatile organic compounds (VOCs) — Specification is expected to be available for comment from 1 July.

This new standard is intended to raise the reliability of sampling soils for determination VOCs in the UK by introducing methods in common use in other countries including Australia and the United States for over twenty years. Its introduction will have profound impact on how companies carry out sampling for VOCs and require close cooperation between those carrying out field work and analytical laboratories. 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.

BS10176 will be a standard specification which means that it 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.

Laboratories are required to provide pre-prepared sample containers prepared to the specification provided in the standard and 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.

It is expected that in future any VOC results not obtained in accordance with BS 10176 could be rejected by assessors and regulators.

It is essential, because of the potentially significant impact on how site investigations are carried out, that potential users including laboratories properly scrutinise the draft standard and raise any issues they consider important using the BSI commenting system which is expected to be live from 1 July to 31 August (use link – https://standardsdevelopment.bsigroup.com/). Copies of the draft standard are available to AGS members from AGS.

The Drafting Panel for the new standard is chaired by Geraint Williams of ALS (geraint.williams@alsglobal.com), a member of the AGS CLWG and AGS laboratories group. Mike Smith, a member of the CLWG, is also on the drafting panel.

Article provided by Mike Smith of M A Smith Environmental Consultancy.

Article

Using Survey Information for New Drains and Sewers

- by
Tags: Featured

As pressure increases to use brownfield sites for new housing, the specialist skills involved in assessing the risks that contaminants pose to the quality of the water entering the surface water drainage and foul water sewerage system from the surrounding soil, is vitally important to house developers and water companies. The BPF Pipes Group has prepared a new guide “Designing drains and sewers for brownfield sites” providing drainage engineers with clear advice on choosing a pipe which will be fit for the long term, starting with the information available to them from the investigation of potentially contaminated land and drawing on the materials expertise from pipe manufacturers.

Effect of contaminants on ingress

An initial flow diagram in the guide sets out a step-by-step process for the drainage engineer to identify if a quantitative risk assessment has been carried out, whether the contaminants could pose a risk if left in the ground and whether the source or the pathway might be removed due to the proposed remediation plans.

The geotechnical specialist undertaking the quantitative risk assessment and options appraisal can support the drainage engineer by drawing out the essential information from the site history and soil sampling:
• confirming where there is (and is not) a possible source of contamination – this is particularly pertinent on large sites with a mixed history of use;
• clearly setting out what chemicals are present from the many included in the test report and in which zones (areas) of the site; and
• explaining the mitigation strategies proposed so that any impact on the source of contamination or the pathway can be recognised.

Suitability of materials for drains and sewers

A second flow diagram in the guide assists the engineer to identify the impact that residual contaminants may have on plastic pipe materials.

Where organic compounds are shown to be present in the soil, the guidance provides limits for PAH, BTEX and TPH which represent a safe level with respect to long-term performance of polypropylene, polyethylene and PVC-U pipes. The engineer is again reminded that any remediation activities which might remove the source of the contamination or the pathway to the drainage or sewerage system would render these limits superfluous.

Working together

The BPF Pipes Group guide provides practical assistance on designing drains and sewers for brownfield sites.

However, to be truly useful to the drainage engineer, it requires that a risk assessment has been completed, an options appraisal has been carried out to identify solutions, and that the geotechnical specialist provides information in a form which can readily be used in the decision-making process.

Working together, clear and targeted information can be offered, ensuring the longevity of the surface water drainage and foul sewerage networks on brownfield sites.

The guide is available on its website at www.bpfpipesgroup.com/support-downloads/guidance-notes.

Article contributed by the British Plastics Federation Pipes Group

Article Contaminated Land

AGS Guidelines to Good Practice in Geoenvironmental Ground Investigation – Update

- by
Tags: Featured

It has long been the aim of the Contaminated Land Working Group to produce a definitive guide to ground investigation good practice similar to that produced for Geotechnical Ground Investigation in 2016. As with many things in life, I feel that this has rather been eclipsed by events. The definition of good practice has certainly changed over time and the available standards and guidance available from BSI, ISO, CEN, AGS, CIRIA, CL:AIRE and many others continues to develop around us. Indeed, there is a veritable treasure trove of training and advice available on almost any aspect of site investigation, sampling and monitoring you care to consider and keeping up with them all, and especially acting on them, can be a job in itself. This is even more true if you subscribe to or work under ISO9001 et al. With the publication of the ISO BS 18400 series on Soil Quality, hopefully some of this existing variation will be resolved, rationalised and summarised to some extent.

Having been in this business for over 25 years now, training students, young practitioners and fellow professionals in the art and science of site investigation, sampling and monitoring as well as being current chair of BSI EH/4 (responsible for BS10175), I am perhaps more aware than most of the sheer range of material out there. Indeed, I have noted on previous occasions that if stacked on top of each other, the guidance alone would probably reach to your waist. So, do we really need any more guidance on this topic? Well perhaps the main reason for doing so would be to at least provide a road map and summary of where to find all the other information you might need to know (or at least should know about) when undertaking or commissioning a ground investigation.

Firstly though, we should step back and consider what ground investigation actually is and why we undertake them in the first place. In simple terms investigation is the process used to determine and quantify remaining unknowns from the Conceptual Site Model (CSM). As such, actual ground investigation can come in many forms, types, phases and be given many (often confusing) names depending on how, where, when and what is planned. For a Desk Study or preliminary investigation for example this is usually as a site visit and observation and then remotely from the office following a review of the available data.

If, following an initial assessment of the CSM, a risk has the potential to be present, potentially significant unknowns remain and/or further quantification of perceived issues is required, we then move on to designing the intrusive or main investigation phase. This should be based on and reflect consideration of a range of factors depending on both what we know and what we don’t and should ultimately dictate where we look, sample, install and monitor real world locations and materials. This can be followed by any number of additional supplementary investigations to confirm specific aspects, the most common of which is probably undertaken to determine the extents, composition and nature of identified deleterious materials to thereby assist in the production of a site-specific materials management plans and/or remediation strategy.

So, given the above, what is Geoenvironmental Ground Investigation? This is somewhat of an open question really and as with many things depends ultimately on context and perception. For Geoenvironmental practitioners, I think the clue is in the name and should be about following a scientifically justifiable, recordable and systematic approach to digging holes in the ground and finding out what’s there. What happens afterwards is a whole topic and world of its own beyond the scope of consideration in this discussion, but should be considered and questioned when designing any investigation. What you plan to do with the data you will gather should in part, through consideration of the CSM, resources, available analysis, analytical tools available, etc. dictate what data you actually get from the investigation. Failure to appreciate this aspect from the start of the process can sometimes lead to quite significant problems and costs further down the line.

So, where do we go from here? Well a good stop-gap and the method I would generally suggest at the moment as a starting point to anyone who asks, is to look to the various standards that guidance themselves reference, especially given that all good practice should ultimately be standards driven or at least backed by standard references. BS10175 is a good summary of most of what you need to know when investigating potentially contaminated land and has extensive references to other relevant standards including in the most recent update/revision, the BS ISO 18400 series. So how would I write an AGS guidance note for good practice in Geoenvironmental ground investigation? Well I can certainly think of worse than a white page with a large arrow pointing to the latest version of BS10175 and the BS ISO 18400 series. But, as I chair of the committee that looks after all of this for BSI, I suppose I would say that wouldn’t I….

Opinion piece provided by Chris Swainston, Principal Environmental Engineer at Soils Limited