Company capability. Site works Cable percussion drilling Rotary drilling Dynamic sampling Trial pitting In situ testing

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1 Onshore site investigations for new nuclear build companies (EDF Energy) and Wylfa, Anglesey (Horizon Nuclear Power) Ground investigation at Loch Lomond for A82 realignment for Transport Scotland Ground investigation for Blackfriars station redevelopment for Network Rail Geotechnical and environmental investigation at Barry for Taylor Wimpey, Persimmon Homes and Barratt Homes Ground investigation for new reservoir at Darenth Reservoir, Kent, for Thames Water Geotechnical ground investigation for replacement lifeboat station and slipway at base of sea cliff at the Lizard for Royal National Lifeboat Institution Company capability Structural Soils Limited is a British company established in 1964 as a site investigation contractor. Based in Bristol, with branch offices in Castleford near Leeds, Hemel Hempstead and Glasgow, the company operates throughout the United Kingdom and undertakes overseas contracts. With over 40 years experience, the company has an impressive list of clients including consulting engineers, architects, local and statutory authorities, government bodies, limited companies and private individuals. The company s experience provides a sound knowledge of all aspects of geotechnical engineering, and Structural Soils staff are always ready to give advice. As the company operates various boring and drilling rigs and associated equipment, an investigation can normally be designed to suit the client s requirement and obtain information in the most efficient manner. Samples are tested in the company s own well-equipped UKAS-accredited laboratories in Bristol, Castleford and Hemel Hempstead. The technical staff are highly qualified and include civil and structural engineers, geologists, engineering geologists, chemists and environmental scientists who prepare both factual and interpretative reports in accordance with the client s requirements. Structural Soils continuing growth is enhanced by its reputation, competitive rates and quick response. Becoming a member of RSK in 2007, the company can also offer other group services such as ecology and geophysics as part of overall site investigations. Furthermore, chemical testing is undertaken within the group. Our expertise includes the following key areas. Site works Cable percussion drilling Rotary drilling Dynamic sampling Trial pitting In situ testing Laboratory testing Geotechnical Chemical Reporting Factual Interpretive Geotechnical consultancy Expert witness SS0027a_3

2 Our clients Highways Agency Network Rail EDF Taylor Wimpey Thames Water Transport Scotland Recent projects Onshore site investigation at Hinkley Point for EDF Ground investigation for Blackfriars station redevelopment for Network Rail Environmental investigation at Gas Place car park in St Helier, Jersey, for Jersey Transport and Technical Services Site investigations With an increasing proportion of developments occurring on previously developed brownfield sites and ever more challenging greenfield sites chosen for development, there has never been a greater need to carry out adequate site investigations. A suitable site investigation can often lead to project cost savings in the long term, allowing contractors to foresee problems and make savings. Structural Soils Limited (an RSK company) employs a wide variety of site investigation techniques from desk studies to fieldwork to suit any size of project. The team of engineers can advise on suitable methods for individual projects ranging from small-scale investigations to larger ones for major civil engineering works. The investigations usually include both geotechnical and environmental work. The following site investigation techniques are employed for the majority of projects: trial pitting window sampling and dynamic probe testing cable percussive boreholes rotary drilled boreholes. Laboratory testing Site work is followed by both geotechnical and chemical testing. Geotechnical testing is undertaken in the company s UKAS-accredited laboratories in Bristol, Hemel Hempstead and Castleford, while chemical testing is undertaken by an accredited laboratory with which we have strong and long-standing relations. Presenting results Results of site investigations can be presented as either factual or interpretative bound reports with recommendations relating to both geotechnical and environmental considerations. Exploratory hole data is presented following the guidelines of Eurocode 7 Geotechnical Design and can also be presented electronically in standard AGS format. The company is accredited to an integrated management system encapsulating ISO 9001, ISO and OHSAS For additional information on any of these services and our associated experience, a series of dedicated product sheets is available. Please contact us to find out more. SS0028a_3

3 Port Talbot A geotechnical and environmental investigation was required for a residential development on the site of an old steelworks and chemical plant. As the site was readily accessible, the environmental investigation was based on the use of 180 trial pits, although several boreholes were also sunk mainly for geotechnical purposes. Recovered samples were sent to a chemical laboratory for analysis and geotechnical testing was undertaken in the company s Bristol laboratory. The client was the Welsh Assembly Government and the engineer was Opus International. Knowle, Solihull A site investigation was undertaken for the redevelopment of existing farm buildings into an eco-office complex. The investigation included 27 hand-dug pits to investigate existing foundations and 2 machine-dug pits for soakaway testing. The client was RBH Holdings Ltd and the engineer was Gifford Ltd. Trial pitting Structural Soils Limited (an RSK company) carries out trial pitting using a variety of methods from hand-dug pits to machine-excavated trenches. Trial pitting is generally carried out to a maximum depth of 4.5 m with standard excavation plant and, dependent on soil conditions, is generally suitable for most low-rise developments where traditional shallow foundations are envisaged. All trial pit investigations are supervised by experienced staff with a thorough understanding of geology and soil mechanics. Additional testing in trial pits can include soakaway testing, CBR testing and in situ strength testing. How can we help? If you are planning any development involving construction you are likely to require a site investigation. We are always pleased to offer advice at an early stage and will provide information on geology, recommended investigation techniques and suggested scopes of work, usually without charge. In return we would expect to be invited to quote or provide a price for the investigation. Owing to our competitive pricing structure, we win approximately 40 50% of contracts priced. We then undertake the works using the most relevant equipment available. Common methods used on site include trial pitting, dynamic sampling, cable percussion drilling and rotary drilling, but we also have access to geophysical methods and static cone penetration testing. Geotechnical laboratory testing is undertaken in our laboratories in Bristol, Castleford and Hemel Hempstead, and chemical testing is undertaken by an accredited laboratory with which we have strong and longstanding relations. Factual and interpretive reports are prepared by our team of experienced engineers, geologists and environmental scientists, and provide advice on foundation solutions, contamination levels and remediation options. SS0029a_3

4 Bridgwater, Somerset An environmental investigation was required on a 27-ha closed cellophane factory. Although the work included cable percussion and rotary drilling, the environmental investigation was based mainly on the use of dynamic sampling. A total of 136 dynamic samples were sunk to depths of 5 m. The method used enabled access to be gained to all parts of the works. Samples recovered were tested via a UKASaccredited laboratory and a factual report prepared for Scott Wilson (the engineer). The ultimate client was Innovia Films. Exeter A ground investigation was undertaken to provide information for the refurbishment of the Royal Albert Memorial Museum in Exeter. The work included 24 hand-held and track-mounted window sample holes, largely to profile the defensive earthworks of a Norman castle. Exeter City Council was the client and the engineer was Building Design Partnership. Dynamic sampling and dynamic probe testing Dynamic sampling (or window sampling) is carried out by either track-mounted percussive samplers or hand-held equipment. Samples are retrieved in seamless plastic tubes for logging by a suitably qualified engineer. Window sampling is suited to restricted access sites, limited depth contamination investigations, and where disturbance must be kept to a minimum. The track-mounted equipment is also capable of carrying out dynamic probe testing, which is a continuous soil test procedure to enable correlation with relative density and shear strength of strata. How can we help? If you are planning any development involving construction, you are likely to require a site investigation. Structural Soils Limited (an RSK company) is always pleased to offer advice at an early stage and will provide information on geology, recommended investigation techniques and suggested scopes of work, usually without charge. In return we would expect to be invited to quote or provide a price for the investigation. Owing to our competitive pricing structure, we win approximately 40 50% of contracts priced. We then undertake the works using the most relevant equipment available. Common methods used on site include trial pitting, dynamic sampling, cable percussion drilling and rotary drilling, but we also have access to geophysical methods and static cone penetration testing. Geotechnical laboratory testing is undertaken in our laboratories in Bristol, Castleford and Hemel Hempstead, and chemical testing is undertaken by an accredited laboratory with which we have strong and long-standing relations. Factual and interpretive reports are prepared by our team of experienced engineers, geologists and environmental scientists, and provide advice on foundation solutions, contamination levels and remediation options. SS0030a_3

5 West Ham, London Ground investigation for a flood alleviation scheme including a deep sewer access shaft. The site work included 12 cable percussion boreholes to 20 m depth, several of which were extended to 40 m depth by rotary coring. Multiple casing strings were required owing to contaminated ground, and there was an unexploded ordnance risk on the site. The client was Thames Water and the project value was 200,000. Sizewell C Supplementary ground investigation to establish geotechnical and chemical properties of a body of peat. Work included forty 10-m cable percussion boreholes with piston sampling. The client was British Energy and the project value was 110,000. Cable percussive boreholes For large-scale projects and where difficult ground conditions are encountered at a site, cable percussive boreholes are a common method of site investigation. Using a Land Rovertowed rig or a specialist cut down rig suited to restricted access locations, most sites can be investigated. In situ testing techniques including standard penetration testing, permeability testing and borehole vane testing can all be carried out in the boreholes in order to allow our engineers to provide information for geotechnical design. Disturbed and undisturbed samples are retrieved from the boreholes for inspection by engineers and subsequent testing in our laboratories. Instrumentation such as gas and groundwater monitoring standpipes, piezometers, inclinometers and extensometers can be readily installed in cable percussion boreholes. Boreholes are logged by suitably qualified engineers and geologists. How can we help? If you are planning any development involving construction, you are likely to require a site investigation. Structural Soils Limited (an RSK company) is always pleased to offer advice at an early stage and will provide information on geology, recommended investigation techniques and suggested scopes of work, usually without charge. In return we would expect to be invited to quote or provide a price for the investigation. Owing to our competitive pricing structure, we win approximately 40 50% of contracts priced. We then undertake the works using the most relevant equipment available. Common methods used on site include trial pitting, dynamic sampling, cable percussion drilling and rotary drilling, but we also have access to geophysical methods and static cone penetration testing. Geotechnical laboratory testing is undertaken in our laboratories in Bristol, Castleford and Hemel Hempstead, and chemical testing is undertaken by an accredited laboratory with which we have strong and long-standing relations. Factual and interpretive reports are prepared by our team of experienced engineers, geologists and environmental scientists, and provide advice on foundation solutions, contamination levels and remediation options. SS0031a_3

6 Pulpit Rock, Loch Lomond, Scotland A tunnel has been proposed to relieve congestion on a section of the A82 adjacent to Loch Lomond. To investigate the tunnel route, coring in rock was required. Owing to difficult access, rotary drilling rigs were lifted by helicopter to locations above the proposed tunnel so that boreholes up to 40 m deep could be drilled. The client was Transport Scotland and the engineer was Scott Wilson. The project value was 600,000. Llyn Alaw Reservoir, Anglesey Eleven rotary boreholes were drilled through both the crest and the toe of a 1960s concrete dam that impounds a reservoir supplying water to Anglesey. The dam lies within a site of special scientific interest. The dam crest was 1.6 m wide and boreholes were inclined to miss the grout curtain. Packer tests were undertaken, and vibrating wire piezometers installed in the boreholes. The engineer was Atkins and the client was United Utilities. Rotary drilled boreholes Rotary drilling techniques are employed where boreholes are required into very dense gravel or bedrock. Both open hole and cored boreholes are drilled depending on the requirements of the investigation, using a variety of equipment and flush media. Instrumentation such as gas and groundwater monitoring standpipes, piezometers, inclinometers and extensometers can be readily installed in rotary boreholes. Intact cores are recovered in seamless plastic tubes for subsequent logging by a suitably qualified engineer and for laboratory testing. Most of our rotary coring work relies on the use of our own drilling rigs, some of which are suitable for limited access work. Insitu testing such as standard penetration tests, packer tests and pressuremeter tests can be carried out in rotary boreholes. How can we help? If you are planning any development involving construction, you are likely to require a site investigation. Structural Soils Limited (an RSK company) is always pleased to offer advice at an early stage and will provide information on geology, recommended investigation techniques and suggested scopes of work, usually without charge. In return we would expect to be invited to quote or provide a price for the investigation. Owing to our competitive pricing structure, we win approximately 40 50% of contracts priced. We then undertake the works using the most relevant equipment available. Common methods used on site include trial pitting, dynamic sampling, cable percussion drilling and rotary drilling, but we also have access to geophysical methods and static cone penetration testing. Geotechnical laboratory testing is undertaken in our laboratories in Bristol, Castleford and Hemel Hempstead, and chemical testing is undertaken by an accredited laboratory with which we have strong and long standing relations. Factual and interpretive reports are prepared by our team of experienced engineers, geologists and environmental scientists, and provide advice on foundation solutions, contamination levels and remediation options. SS0032a_3

7 Waterfront, Barry Barratt Homes, Persimmon Homes and Taylor Wimpey required a 310,000 investigation to check for contamination and enable foundation design for a proposed residential and commercial redevelopment of an 88-acre site. Former uses of the site included ship repairs, engineering works, coal jetties and tramways, and the potential for associated contaminants required the use of full chemical protection suits. Seven weeks of site works involved 230 trial pits, 48 cable percussion holes and 30 rotary holes. Groundwater monitoring and sampling, surface water sampling and gas monitoring then took place, followed by factual reporting of the works. Rivermead Leisure Centre An extension was proposed for an existing leisure centre that lay upon a former landfill site. Following a desk study, two investigations were undertaken utilising cable percussion boreholes and trial pits. Gas/groundwater monitoring wells were then installed and monitored. A human health risk assessment and gas risk assessment led to remediation proposals and subsequent validation. A groundwater risk assessment (RTM/P20) was undertaken, followed by further long-term sampling, testing and reporting for water quality. Contaminated site studies Environmental phase 1 studies Structural Soils Limited (an RSK company) has extensive experience of undertaking phase 1 (environmental and historical) desk studies. These utilise high-quality site-centred Ordnance Survey historical mapping from the late nineteenth century to the present day, and comprehensive environmental database searches. This study determines if the site and surrounding area have been subject to potentially contaminative use and gives information on other aspects such as landfills, radon, watercourses, aquifers and public water supply abstractions. Environmental phase 2 site investigation Environmental site investigation often utilises the low-disturbance technique of dynamic sampling, as well as excavator-dug trial pits and cable percussion boreholes. Standpipes are often installed for the monitoring and sampling of groundwater and soil gases by our site technicians. We have investigated sites with varied historical uses including petrol stations, factories, abattoirs, landfills, timber treatment works, scrap yards and foundries. The proposed developments are again varied, with the most sensitive end use generally being residential. Consultancy and phase 3 work We have extensive consultancy experience in the redevelopment of brownfield land and the assessment of risk to human health and groundwater. We can assist with the design, supervision and validation of the remediation process. We also liase with local authorities, the Environment Agency and the National House-Building Council during investigation and remediation. Qualitative and quantitative risk assessments can be undertaken to ensure that remediation projects address all the issues that may give cause for concern. Structural Soils also assisted the client with regulator liaison and helped obtain waste exemption certification. SS0033a_2

8 Upper Osprey Site, Portland Laboratory testing for Hydrock to provide parameters for slope stability analysis following failure of a slope on the island of Portland. The testing included effective stress triaxial, soils shearbox and rock shearbox testing. The value of the project was 17,000. Shrinkability projects The laboratories regularly undertake plasticity index testing to establish the shrinkability of clay soils. This is undertaken regularly for numerous clients designing residential developments. Soils, rock and material testing Structural Soils Limited (an RSK company) operates three geotechnical laboratories. The company s main laboratory occupies the ground floor of the Old School in Bristol, which has been converted to provide well-equipped facilities for soil, rock and material testing. Laboratories are also situated within our offices at Castleford and Hemel Hempstead. Soils are tested in accordance with the latest standards and the full range of tests specified in BS 1377, Methods of test for soils for civil engineering purposes, are available. All three laboratories are UKAS accredited. The Bristol laboratory includes a modern effective stress facility and undertakes triaxial testing up to 100-mm diameter, shear box testing up to 300 x 300 mm, and ring shear testing. Work is undertaken not only for the company, but also on a subcontract basis for other site investigation contractors. Tests on concrete and other construction materials are also undertaken either on site or in the laboratory with a sample collection service being available. In situ testing services provided by the company include soakaway, plate bearing and California bearing ratio testing. Monitoring services including gas, groundwater, piezometer and inclinometer monitoring are performed on a regular basis. SS0034a_2

9 What is Eurocode 7? Eurocodes are a European suite of codes for structural design. They replace the current British Standards as the primary specifications for designing structures in the UK, a process that was mostly completed on 1st April Eurocode 7 Geotechnical Design introduces a number of changes in the way in which ground investigations are designed, undertaken and reported, and how the findings are interpreted. Why does this affect me? Following the withdrawal of support for older national design codes, clients and employers are increasingly requesting Eurocode-compliant services and may be required to do so by contract law in the future. Structural Soils and Eurocode 7 What does Eurocode 7 mean for ground investigation? Key changes brought about by Eurocode 7 are the provision of new guidance on the number of exploratory holes and the amount of laboratory and testing in situ that should be undertaken amendments to official soil and rock descriptions (previously given in BS 5930: 1999), for example, new strength terms have been introduced to describe cohesive soils a new stipulation that common in situ test equipment such as the standard penetration test (SPT) hammer should be calibrated for efficiency two new types of report are specified: the ground investigation report (GIR), which presents and evaluates geotechnical information, and the geotechnical design report (GDR), which provides foundation design recommendations that include a statement of assumptions, statements of codes applied and methods of calculation used, design calculations and drawings, and recommendations for on-site verification during construction. Why choose Structural Soils as your ground investigation contractor? Structural Soils (an RSK company) recognises the importance of Eurocode 7; we undertake compliant investigations and provide GIR reports if required. While GIR and GDA reporting is expected to become the norm rather than the exception in the future, we continue to offer our existing factual and interpretive reports to customers who do not currently require a GIR or GDR, or who wish to develop their own GIR and GDR reports from the information we supply. Structural Soils has completed extensive staff training to remain Eurocode compliant. All our company s soil and rock descriptions have been compliant with Eurocode 7 since July All of our company s SPT hammers and dynamic probing equipment is calibrated regularly, and we have invested in new equipment such as the UT100 thin-walled, open-drive sampler. Where can I learn more? Contact Adam Lumber or Jim Southern via the details below or visit For further information visit us at or contact Adam Lumber: [email protected] or Jim Southern: [email protected] (Tel: +44 (0) ) SS0104_5

10 In situ testing Structural Soils provides a broad range of in situ tests. Our trained and experienced technicians are typically available for next-day on-site deployment UK-wide, and can provide information and advice based on their in-depth industry experience. Our policy of rapid response and a very quick turnaround on processing results will support you in meeting your deadlines. Testing includes: California bearing ratio testing (CBR) A penetration test for evaluation of the mechanical strength of road sub-grades, which is usually carried out on site using a vehicle-mounted CBR machine. A load is applied to a standard plunger that penetrates a soil sample in order to determine the resistance to deformation under load. Regular penetration readings are taken as the load is increased. The results give the CBR value for the soil and allow the road pavement to be designed to suit the geology. Plate bearing testing (PBT) A method to test the bearing capacity of the ground to determine settlement under load on soils, fill and sub-base, and to calculate the modulus of sub-grade reaction (k value). The test is carried out by subjecting steel plates of varying sizes to gradually increasing loads, and will indicate if the ground is suitable for the proposed development. The readings can also be used to calculate various other values, including equivalent CBR on materials too large for standard CBR tests. Sand replacement density testing (SRD) A method for the determination of the dry density of undisturbed or compacted soils and granular materials by sand replacement. The test is carried out by excavating a cylindrical hole in the ground before replacing the excavated material with sand of a known density through a calibrated cone. Nuclear density gauge testing (NDG) A test to establish the moisture content, wet density and dry density of soils and granular construction materials. Measurement of soil density is most commonly used to assess whether material used as backfill, lining or capping (eg. road and landfill construction) has been adequately compacted. The site operation is non-destructive and, as results are available immediately, the test causes minimal downtime for the contractor. This method makes use of low-level radiation, so site personnel are fully trained and strictly adhere to health, safety and environmental procedures. Soakaway/infiltration testing A test to establish infiltration rates across varying geology. Drainage is a critical issue, whether you are building property or maintaining a golf course. Soakaways have been the traditional way to dispose of storm water from buildings and paved areas remote from a public sewer or watercourse. They are being increasingly used within urban, fully sewered areas to limit the impact on discharge of new upstream building works and to avoid costs of sewer upgrading outside a development. Infiltration testing (permeability) is an important part of assessing the drainage capabilities of any given ground material. Soakaway testing involves excavating a trial pit of sufficient size to represent a section of the design soakaway. The pit is then filled with water several times in quick succession whilst the rate of seepage is monitored. For further information visit us at or contact Sam Handcock: [email protected] ( ) SS0205_1

11 service sheet Overwater Structural Soils provides nearshore coastal, estuarine and inshore site investigations for infrastructure developments such as harbours, marinas, jetties and pipeline landfalls. We are well equipped with overwater plant and equipment to undertake surveys using floating craft and/or static jack-up platforms, depending on the requirements, location, environment and timescale of the proposed investigation. The capabilities and experience of our overwater team combined with the availability of the wide choice of plant and equipment enable us to meet the technical and logistical demands of the nearshore and inland water industries. SS0156_1

12 APPLICATIONS n Studies for offshore and inshore structures n Calibration of geophysical data n Offshore laboratory testing n Geohazard evaluation n Geological investigations INVESTIGATION TECHNIQUES The investigation techniques we have available range from vibrocoring, grab sampling and seabed cone penetration testing for shallow seabed investigations to cable percussion, traditional, wireline rotary and downhole cone penetration testing for projects requiring greater depths of investigation. Our plant enables us to operate in depths of to 25 m while achieving drilling depths in excess of 100 m below the seabed. All our overwater plant can be operated in conjunction with a GPS for identifying and recording investigative positions during surveys, irrespective of their distance from shore. PLANT Zee Jack Inspector jack-up system and Steady 400 safety boat A purpose-built jack-up system, the Zee Jack Inspector provides a stable, elevated environment that supports conventional static drilling and in situ testing in water depths to 25 m. The m jack-up platform is fully road demountable for ease of transport and rapid deployment. The jack-up system comes complete with a Steady 400 safety boat and can be fitted with a deck-sited welfare unit. The jack-up system can also be supplied skippered without drilling equipment for use as a working platform with a 15-t load capacity. Zee Shrimp inshore boat Our 120-hp Zee Shrimp safety boat has been designed to be highly transportable. It can be fully equipped as a nearshore/inshore workboat and is an ideal small tug for manoeuvring the Zee Jack Inspector jack-up platform in sheltered waters. ADDITIONAL SERVICES Structural Soils can also help with every aspect of land-based site investigation and contaminated land studies, as we have experienced PTS-, CSCS- and NVQ-certified drilling crews and qualified engineers who can log samples and interpret test data. We have a range of equipment suitable for drilling soil, dense gravel and bedrock. Our towed, track-mounted and specialist cut-down rigs can investigate most sites, including restricted access locations. The disturbance of contaminated land can be kept to a minimum and monitoring instrumentation can be installed. Steady 400 Explorer 1 Made from rotational-moulded polyethylene, the Steady 400 has a 1000-kg capacity, will plane at 10 knt while producing very little wake and is extremely manoeuvrable. Its fiveperson capacity makes this versatile boat ideal for a range of applications, particularly in sensitive environments. Our Explorer 1 lightweight aluminium dory is fitted with a 15-cm upstanding moon pool, which makes it ideal for shallow-water sediment sampling. CONTACT Michael Addinall Structural Soils Overwater Team Tel +44 (0) Mob +44 (0) [email protected]