I started my career as an assistant geologist with Soil Mechanics in 1978, which later traded as ESG and in 2017 was acquired by Socotec. Over those ensuing 40 years, I've seen significant changes in how the ground investigation (GI) industry is organised in the UK.
Stephen Tomlinson (left) receiving his Lifetime Achievement Award from Martyn Brocklesby, the chair of the British Drilling Association
In the 1970s and early 1980s, GI was managed by a few London-based consultants with five or six major regional GI contractors carrying out most investigations. Many of the GI contractors were owned by large civil engineering contractors working with in-house rigs and operatives and little, if any, borehole construction was subcontracted out. As an assistant geologist, you could be on site anywhere in the UK or overseas.
From the mid-‘80s many more consultants became involved with geotechnical work and the sector became regionalised with GI teams spread around the major cities of the UK. At the same time subcontractors, both cable tool and rotary began to take over from in-house crews leading to the proliferation of SMEs who act as the GI management contractors we see in the industry today. This expansion has provided nationwide job opportunities for young geologists and engineers who want to work in ground investigation. Regionalisation, however, limits their experience to the ground conditions and techniques appropriate to their local area. It is to the detriment of the industry that young staff and operatives miss out on a broader national and worldwide education and experience than when I was in the formative years of my career.
RIG DEVELOPMENT
There has been little if any advancement in cable tool boring rig design over the last 40 years with the recent exception of the complete redesign of the cable tool rig to comply with health and safety legislation. The new cable tool rig has still to prove its capability in the field and with the number of ‘old-style' rigs still in operation, it will be a few years before this new design makes any impact.
Rotary rigs are the opposite to cable tool; seeing significant changes to design in the last 40 years. In the late 1970s, the majority of GI rotary rigs were direct mechanical drive, spindle type, very few were the top-drive, hydraulic rigs we are familiar with today. The switch to top-drive units with the trend for them to be more compact was driven by industry requirements for a rig capable of hole construction using a wide-range of drilling techniques and an increased focus on health and safety. It was unheard of in the 1970s and 1980s to see a GI rotary rig fitted with break out clamps and holding clamps, interlocked safety cages, remote control for both drilling and tracking, dynamic sampling hammers, wireline winches, on-board flush pumps, etc, all of which are fitted as standard on most rotary rigs today. Those changes have been driven by health and safety legislation. Hopefully, these improvements will continue benefiting operatives and making companies adopt plant upgrade strategies instead of the stop/start capital investment programmes I have witnessed throughout my career. Lead drillers should have modern, efficient and safe plant to work with.
At the start of my career, rotary drilling was usually restricted to rock but over the last 40 years it has expanded to include core drilling to obtain Class 1 samples in soils with Geobore S dynamic sampling of overburden and drill and case systems to advance boreholes through obstructions and ground not ideal for cable tool boring or core drilling. I first worked with the predecessor to Geobore S on GI for the proposed Baghdad Metro in 1982/3. Soil Mechanics then introduced this system into the UK in 1984 and it has since become the standard method of core drilling in many different materials to provide high-quality 100mm diameter samples for laboratory testing.
In 1987 I was involved with the GI for the Dalton-in-Furness bypass where Geobore S was first used in glacial till to provide Class 1 samples replacing cable tool boring, which was unable to advance through large boulders.
In the last 10 years, sonic drilling has made a significant entry into the UK market and has proved very successful in overburden materials such as glacial till in which cable tool boring and core drilling struggle to advance the hole and retrieve samples. It is also been used extensively in ground contamination studies in the UK to provide specimens for laboratory tests, which have not been affected by the drilling process.
Who had heard of geo-environmental investigations in the late ‘70s? They started to appear in the late '80s when heavily contaminated industrial areas left derelict after the restructuring of the UK economy became available for development.
I was involved in the first large ground investigation with a substantial geo-environmental element carried out for the Black Country Spine Road in the West Midlands. No ground investigation these days is complete without a geo-environmental element and the requirements of this sector led to the development of techniques such as window sampling, dynamic sampling and the introduction of sonic drilling to the UK. Aligned with increased awareness of ground and groundwater contamination has been the significant increase in awareness of the environmental impact drilling works have not just on the nearby ecological system but also on the local human population. This can only be a development for the better.
Other developments and improvements over the last 40 years include the introduction of small self-elevating jack-up platforms suitable for use in the civil engineering sector, which have made the construction of boreholes in tidally affected waters easier and safer, and the development of sophisticated high-pressure dilatometers and self-boring pressure meters as well as the introduction of the measurement of drilling parameters during borehole construction.
HEALTH AND SAFETY
The most significant change in the UK drilling industry over the last 10 to 15 years has been the introduction of much-improved health, safety and welfare driven by changes in legislation aimed at improving the general health and safety of construction workers. Forty years ago, you would have worn a pair of safety boots and possibly a safety helmet. Today drill crews are kitted out in good quality work wear and PPE, good welfare facilities are provided, and there is health monitoring through programmes like Constructing Better Health.
These changes can only be seen in a positive light and are a massive improvement over where we were 40 years ago; long may these improvements continue. Safety improvements, such as the production of task-specific RAMS, morning briefings, task-specific toolbox talks, open and honest reporting of incidents and near misses and a willingness to raise concerns, have to be a significant improvement on where the industry was even 20 years ago.
Major clients such as HS2 are constantly driving health and safety changes and improvements and this will only continue as they attempt to reduce the potential for a serious incident.
On-site health and safety is better today but there is still room for improvement
As an industry, we need to improve how we manage health and safety on-site. On several very large contracts, I have been responsible for a full-time, on-site health and safety manager has been factored in at tender stage and involved pre-mobilisation and during the site works. In the future, I would like to see clients on major infrastructure projects requiring a full-time, qualified health and safety manager to be on site during the GI.
Linked to improved health and safety is a significant improvement in the training and annual auditing of drill crews over the past 15 years. The British Drilling Association (BDA) first introduced the Driller Accreditation Scheme in 1990, prior to this drillers had no proof of competency or formal training. The Scheme required a driller to be assessed as competent to perform his role, but formal training and annual audits were some way off. In 2000 the NVQ for Drillers was established and in 2005 the BDA introduced the annual audit.
Over the last five to 10 years formal training for drillers has really taken off with many undertaking courses to operate ancillary plant such as forklifts, personal survival courses for offshore work, 4WD vehicle driving, load slinging, banksmen, working at height, asbestos non-licensed worker, etc. All Socotec in-house lead drillers have undertaken the SSSTS course to improve their understanding of health and safety.
Though training costs money and disrupts work patterns, in my opinion, the current position is a massive improvement on where we were even 20 years ago. Drillers appreciate the training they are given and take the lessons learnt into the workplace. It is a pity some clients and consultants do not police the "yellow book" requirement for BDA audited lead drillers. My hope for the future is that clients and consultants will see the benefits of BDA audited and well-trained drillers and the level of audit uptake will increase. My concern is this will only happen following a serious incident.
DATA MANAGEMENT
Advances in electronic data management have changed how field records are collated, data shared and analysed and how the GI reports are presented. Until the mid-1980s all data was recorded using manuscript record sheets and the borehole logs and laboratory test results for GI reports were prepared using typewriters, draughtsmen prepared site plans, all in situ and lab test results were hand-calculated by the technician or engineer/geologist with final reports being issued as paper copies. The availability of early desktop computers in the mid to late 1980s saw the introduction of the computerised borehole log and monitoring of some lab tests with data acquisition units. The trend for electronic data and monitoring has continued and was boosted when the Association of Geotechnical Specialists (AGS) introduced version 1 of the AGS Data transfer System in 1992.
In 2018, the industry still uses some manuscript record sheets but the continuing trend is for the provision of digital data with daily drilling journals, field logs etc prepared on tablet computers. Monitoring with data loggers in the field and the lab is becoming commonplace. Lab and field tests results are calculated by computer, site plans are produced via CAD and reports are no longer printed on paper but transmitted electronically and data provided in AGS 4 format for import into a database. Though these systems undoubtedly improve data handling and the speed of data transfer, they have diminished the technical quality of the end-product as we removed interaction with the lab technician, geologist and engineer who had the experience to identify when something is not quite right. The computer tells us the answer, so it has to be right, now seems to be the norm. This is also seen in the specifications and bill of quantities that we see every day, which often contain errors and omissions with documents prepared taking no account of the anticipated ground conditions and the type of investigation required.
However, computers provide rapid access to existing information, for example via the BGS website and the rich seam of information you can mine from search engines. It would have been wonderful to have had access to all that information 30 to 40 years ago. When I started in the drilling industry, there was very little published information on borehole construction in the civil engineering sector and you learnt about borehole construction at the rig side talking to lead drillers and observing.
Borehole construction is dominated by males with few, if any, females possibly due to the physical and mobile requirement of the occupation. In the UK 99 per cent of the personnel employed on construction sites are male. More women may be attracted into the industry with increased automation of drilling rigs, which will no doubt occur as technology develops and health and safety regulations are changed to maintain relevance with new technology.
Female engineers and geologists make up less than 10 per cent of the GI workforce and this must improve. Some barriers are being broken down with females holding senior roles in the UK GI contracting and consulting sectors.
GRADUATE RECRUITMENT
The industry needs to recruit and retain top-quality graduates of both genders if it wants to develop and thrive. Like all areas of engineering, the GI sector is struggling to recruit and retain young people. There are many reasons; it could be remuneration, working conditions, unsuitable and unsociable working hours, the mobile nature of the work in the early career stages, the pressurised environment and the increasing health and safety responsibility and consequences. The development of personnel and possible lack of career progression could also be a factor along with the increased use of agency/self-employed staff where earning potential is higher but restricts knowledge and range of expertise.
The GI contracting industry in 2018 does not allow people to develop a wide range of expertise, for example, in borehole design and construction, lab testing, reporting etc, and this is partly due to the dominance of agency and self-employed staff. This disconnect between the various facets of GI, in my opinion, has resulted in a lowering of the quality of the end-product.
The industry needs to give staff time to develop expertise in lots of different areas and reward staff for technical competency and not just commercial acumen. Young engineers and geologists also need to understand that their development and promotion to senior positions may take longer than they believe it should and allow themselves time to gain critical field experience. The same can be said for drillers where the current trend is to get them to lead driller status in two years, again experience and learning from others in the field cannot be replaced.
The drilling industry is not suited to all and young drillers and graduates either love or hate it. Those that love it tend to stick around for a long time and those that hate it move into another sector. Clearly having spent 40 years in the UK GI sector, I must love it. There have been a few jobs that have not gone to plan but even those taught me something. It is not often that I go home at the end of the day without having learnt something new about the drilling industry or myself. It is the variety, challenges comradeship and site banter that has kept me doing it for 40 years. If you want to work in an industry that allows you to travel, meet new people all the time, work with talented people, that constantly challenges you, that occasionally frustrates you and gives you a job with endless variations and lots of fun then I would certainly recommend the drilling industry. If you want a nine-to-five job, home every night, a nice warm office, minimal stress and little variation, do not join the drilling industry, but I guess you already know that because you are reading this article and, therefore, have already been infected by the drilling bug.
Stephen Tomlinson recently retired after a 40-year career in the ground investigation industry. Prior to his retirement, he was principal geologist within the Infrastructure & Energy Division of Socotec
