CONSULTING R05. Geotechnical offshore investigations and consulting, Roskilde Fjord connection SCOPE OF WORKS. Frederikssund Elverdam

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1 SCOPE OF WORKS CONSULTING R05 Geotechnical offshore investigations and consulting, Roskilde Fjord connection Frederikssund Elverdam SEPTEMBER 2014

2 MARINE GROUND INVESTIGATION TECHNICAL SPECIFICATIONS 1. GENERAL PROJECT INFORMATION AND PREREQUISITES 1.1 Introduction The Danish Road Directorate (Vejdirektoratet) is hereafter referred to as VD, while the Roskilde Fjord Link (Roskilde Fjordforbindelsen) is hereafter referred to as the Project. A major part of the project is the Roskilde Fjord High Bridge, a 1360m long bridge crossing the fjord. This document provides the scope of the geotechnical investigations required for evaluating the design and construction of the foundations for the High Bridge. Most of the investigations will be carried out offshore. This document should be read together with the Provisions applicable to contracts and tenders (BUT) and the following Contract Documents: A. Bill of Quantities (TBL) B. Method of Measurement (TAG) C. Scope of Works (YB, this document) D. Management and Cooperation (Styring og Samarbejde) E. Special Conditions for Advisory Services (SBR) F. Drawings Appendix (Tegningsbilag) G. Factual Reports of Previous Ground Investigations (Datarapporter) As the geological and geotechnical conditions along the bridge alignment are known only approximately, the objective of this campaign of geotechnical field and laboratory investigations is to establish the geological and geotechnical situation and to identify the geotechnical design parameters which are needed for evaluation of different foundation alternatives. The final geometric and structural configuration of the bridge (span, width etc.) have not been decided yet so it may be necessary to modify and/or complement the present scope of investigations with additional field and laboratory investigations post tender award. This specification is based on a short span pier layout and as such the investigations locations herein are a possible upper-bound option that is, the design option which requires the greatest number of foundation elements and thus investigation locations. Should the alternate High bridge option be selected by VD, the scope of works may reduce. The requirement for a reduction of the scope will be subject to confirmation by VD.

3 The following documentation has been supplied in the Drawings Appendix and in Contract Document G to provide Contractors with additional information: Bathymetric drawing Conceptual ground model drawing Factual reports of previous ground investigations These documents have been provided for information only and the Contractor should not rely on the information contained within. It is noted that the Project mostly falls in Natura 2000 areas. 1.2 Basis The purpose of this document is to describe the services the site investigation contractor should expect to provide and to specify certain requirements to be met by the site investigation contractor, hereafter referred to as the Contractor. This document addresses the geotechnical investigations needed for the design of the bridge pier foundations offshore and onshore as well as the associated abutments. The services described in the following sections are scheduled to be performed during the period The services to be provided comprise geotechnical investigations for the bridge foundations in the design of the Roskilde Fjord High Bridge. 1.3 The Objective of the Geotechnical Investigations This section presents a description of the scope of the offshore and onshore geotechnical field and laboratory investigations to be completed for the High Bridge section of the Roskilde Fjord Link project. The proposed investigations are necessary to acquire data on which to base the pier and abutment foundation design and choice of foundation type, dimensioning, selection of construction process and operational integrity of the High Bridge structure. The data required includes site-specific information on: Geological soil and rock formations, stratification and variability. Geotechnical soil classification and index properties. Soil strength, deformation and consolidation characteristics. Rock strength and deformation characteristics. 1.4 Scope of Geotechnical Investigation The scope of the geotechnical investigation program, discussed in Section 4 has been developed to assess the vertical and horizontal variability of the seabed soils and to establish the geological origin of soil and rock formations.

4 The full Scope of Works and the obligations of the Contractor are to be ascertained by reference to the Contract Documents as a whole. The following is an overview of the scope: Liaison with the relevant Authorities and Statutory Authorities as necessary to obtain permits and licences to allow the works to be completed. Survey fieldwork locations Field investigations: borings for core recovery, downhole geophysical investigations, soil and rock sampling and standard/cone penetration tests including pore water pressure dissipation test. Routine laboratory testing: soil classification testing and determination of index properties. Advanced laboratory testing: determination of strength, compression and consolidation properties. Data reporting of results of geotechnical technical testing. Provision of draft logs and factual reports Provision of AGS data. The water depth and environment of the fjord may require specialised equipment, and the tenderer must select the appropriate equipment and methods to achieve the specified investigation outlined herein. The investigation has been designed with the aim of providing factual information for the study and evaluation of different foundation alternatives. As the design of the bridge structure has not been finalised, the design solution with the greatest number of foundation elements was selected and the scope of the geotechnical site investigation designed accordingly. 1.5 Time Schedule for Investigations A Gantt chart with the programme of fieldworks, laboratory testing and reporting is enclosed in Appendix B. There are two Contract Milestones for the project which are: Start date scheduled for borehole drilling, in-situ testing etc (ID 4 on the attached programme) Delivery of final factual report (ID 11 on the attached programme) It is envisaged that the offshore geotechnical investigations shall be started by November 2014 and finished by January Particular attention should be paid to potential access / egress issues and water depths in the fjord.

5 The available time period for the investigations shall be considered in the submission when planning the offshore campaign, selecting vessels, platforms and testing equipment, as well as the type and number of investigation units required to complete the campaign in time. A total of 20 investigation locations are planned. These allow for one field investigation per high bridge foundation element: 18no. piers, and 2no. abutments. 1.6 European Standards on Geotechnical Investigation and Testing Geotechnical investigations and testing shall be performed according to the following standards: EN :2004. Eurocode 7- Geotechnical design Part 1: General Rules. Including Danish NA:2013. EN :2007. Eurocode 7- Geotechnical design Part 2: Ground investigation and testing. Including Danish NA: EN ISO :2003 Geotechnical investigation and testing. Identification and classification of rock. Identification and description EN ISO :2006 Geotechnical investigation and testing - Sampling methods and groundwater measurements DGF Bulletin 1 A guide to engineering geological soil description DGF Bulletin 14 Felthåndbogen BS 7022:1989 Guide to Geophysical Logging of Boreholes for Hydrogeological Purposes A list of applicable CEN ISO/TS Geotechnical Investigation and Testing Standards is provided in Appendix A. 1.7 Guidance Documents In addition to relevant geotechnical standards, the guidance document prepared by Technical Committee 1 of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE) gives useful information on executing near-shore and/or offshore geotechnical projects Geotechnical & Geophysical Investigations for Offshore and Nearshore Developments, September Investigations Offshore VD will determine access to the site and location of all exploratory holes. The final borehole locations may change on site from those appearing in contract documents. Final locations will be advised by the Engineer. A notice period of five working days before entry is required.

6 The order of exploratory holes shall be decided by the VD Representative on site. Once an exploratory hole has commenced, it shall be completed continuously and without undue delay. The Engineer s approval is required before commencement and backfilling of each exploratory hole. Geotechnical investigations can be performed from purpose-built drill ships or geotechnical jack-up platforms. This document does not address the specific types and requirements of vessels or drilling platforms needed for the implementation of the proposed investigations. Tenderers should include details of their proposed vessels in their tender return. It is anticipated that the primary method for drilling boreholes in water will be with a Geobor S rig, for example on a jack-up drilling platform. Generally, the water depth in the fjord ranges between 1 and 8 m deep and the equipment chosen should reflect this. Particular care should be taken in areas of soft soils (for example, gyttja anticipated between approximately Ch to 7+100) where leg penetration could be very high and appropriate equipment should be chosen to account for this. Platforms should be capable of supporting both rotary and percussive drilling techniques, high-quality sampling and in-situ testing. When selecting a jack-up unit, consideration should include predicting leg penetration, to ensure that the rig has sufficiently leg length, and that the legs will not punch through during installation. This is of particular importance in areas where soft soils or thin, hard layers overlying softer soils are anticipated. Selection of the vessel or drilling platform is to be made by the contractor, with special consideration given to the above mentioned environments. Additionally, the water depth on the west side of the fjord is low (approximately 1m or less) for up to 200m away from the shoreline, and the contractor must ensure that the selected vessel is capable of carrying out the investigation in shallow waters. Ships conducting coring, or in-situ testing operations, must maintain station vertically above the core/test site. Where water depths are limited and the sea is moderately calm, spud legs may be suitable for keeping a barge in position. 1.9 Positioning System Modern GPS with high accuracies of ±0.01m in X, Y and Z directions (which can be achieved by including signals from existing reference stations, correcting local errors) is required. Such systems are named Differential Global Positioning System (DGPS). In order to limit the necessary number of radio frequencies and for improved reliability and accuracy, it is recommended to use a project specific Global Navigation Satellite System (GNSS) with four reference or relay stations around the project area. These stations would be transmitting signals to a control centre that is transmitting Real Time Kinematic (RTK) data to surveyors working in the project area.

7 The approximate coordinates of the investigations locations are provided in Drawing no. 2 of the Drawings Appendix (Tegningsbilag). The final investigation locations shall be determined by the Contractor within a 6m radius from the coordinates provided in Drawing no. 2 of the Drawings Appendix (Tegningsbilag) Real-time Data Provision The contractor must have the capability of providing the in situ testing data from CPTu in real-time for the Engineer to view online. Borehole field logs must be scanned and ed to the VD Representative and the Engineer at the end of each working day General conditions The Contractor is required to provide and maintain adequate traffic safety and management measures to safeguard the public and site works both during mobilisation and execution of the site investigation works. Measures shall be taken in accordance with any statutory requirements and recommendations contained in the other Contract Documents and any amendments thereto. Where the circumstances of any particular case are not covered by the recommendations, proposals for dealing with this situation should be issued by the Contractor for the approval of the VD Representative a minimum of one week before it is proposed to carry out the works. The Contractor shall provide all lighting, safety barriers, fencing, hand-rails, noticeboards, watchmen and other things necessary to ensure the protection and security of the works and the public, throughout the duration of the Contract. The Contractor is responsible for assessing and providing all necessary support craft, safety barriers, fencing, hand rails etc. to ensure the safety of its operatives and prevention of equipment falling into the sea. The pontoon / barge should be capable of safely operating in the depths of water that are shown in the bathymetric survey in Drawing no.2 of the Drawings Appendix (Tegningsbilag). The contractor should note that this bathymetric survey is only indicative of the seabed at the time survey and no guarantee for its accuracy is provided. A manned safety boat with rescue equipment shall be in attendance whenever personnel are present on the pontoon / barge. The Contractor shall provide the name and contact number of a member of staff who can be contacted (24 hours) by VD in the event of an emergency in connection with the works. The Contractor s Project Leader shall be able to take mobile phone calls from the VD Representative and the Engineer during working hours for the entire duration of the Services. Drilling shall be stopped at any depth at which the Engineer shall be satisfied that sufficient information has been obtained about the subsurface conditions.

8 VD reserves the right to discontinue the work at any time, if in the opinion of the Engineer or the VD Representative, the depth is likely to be excessive or if the sub-surface conditions are such that further drilling would not be beneficial to the project. The Contractor shall obtain approval to proceed from the VD Representative or Engineer prior to moving the drilling/investigation equipment to another investigation location VD Representative s Facilities The VD Representative s Facilities are described in the Contract Document Styring og Samarbejde Transport Transport is described in the Contract Document Styring og Samarbejde Marine Safety Requirements Marine Safety Requirements are described in the Contract Document Styring og Samarbejde Contractors Professional Attendance The Contractors Professional Attendance requirements are described in the Contract Document Styring og Samarbejde. 2. DESCRIPTION OF PROJECT Roskilde Fjord Link at Frederikssund is a dual carriageway highway which includes a high bridge over Roskilde Fjord (henceforth the Fjord ), as described in the Project s Environmental Impact Assessment (EIA) Report under solution S1. The offshore investigation specified herein investigates the crossing of the fjord by the proposed High Bridge. The High Bridge has a length of approximately 1,360m between the abutments and a clear navigation height of 22m above the water.

9 Figure 1 - Aerial view of one of the design solutions considered for the EIA highway scheme in the area of the Fjord [Rambøll EIA 2009, 2010 and 2013] 2.1 Bridge In Figure 2, a representative section of the 1,360 m long bridge is shown, indicating an assumed distance between piers of 73.5 m: this corresponds to Option 2. There are two options currently under consideration: Options 1 and 2 which have pier spans of 82m and 73.5m respectively. Figure 2 - Elevation view of Option 2 for High Bridge, with spans of 73.5m The geotechnical site investigation has been scoped based on the above design option with the greatest number of foundation elements required and the scope of the geotechnical site investigation designed accordingly. 2.2 Bridge Foundations It is generally expected that the bridge piers will be founded on either floating or end bearing pile groups of a number of piles potentially ranging between 12 and 45. The piling technology has not been selected yet. The final design has not yet been established; however the two options being considered have, respectively, 16no. piers with 82m spans or 18no. piers with 73.5m spans.

10 The foundations are estimated to have an area ranging between 60 and 100m2 each, and the foundations and piers are subject to ship impact loads of 5MN applied at 1.5m DVR Abutment foundations The abutment designs have not been finalised, however both the eastern and the western abutment of the bridge are anticipated to be on shallow foundations, based on the preliminary investigations and calculations carried out. Further investigations in the area are necessary and therefore these have been incorporated into this Geotechnical Investigation. 3. PREVIOUS INVESTIGATIONS Several geotechnical and geophysical investigations have been carried out in the area of the fjord for this project. These are enclosed as Contract Document G (Datarapporter) and are summarised in the following sections. These documents have been provided for information only and the Contractor should not rely on the information contained within. 3.1 Geotechnical investigations The known scope of activities undertaken by COWI comprised among others: borehole drilling, in-situ tests (field vane tests (FVT), SPTs and CPTs), geophysical logging, soil sampling (both disturbed and undisturbed), groundwater sampling for chemical analysis, standpipe installation for groundwater monitoring purposes, limited scope of laboratory classification tests, and pumping tests. Previous investigations include the following: a) COWI: Set of the documents dated 2009 (see Contract Document G). These were supplemented with a number of older archive borehole logs sourced from previous investigations within the project area. 3.2 Geophysical Surveys The purpose of geophysical survey undertaken to date has been to document the nature and elevation of the seabed and any objects thereon. In addition, geophysical information can help establishing general geological conditions by identifying various soil and rock layers. Furthermore, these surveys contributed to archaeological and environmental information. The implementation of geophysical measurements and the results are described in the report Roskilde Fjord Connection. Geophysical Seabed and Deep Seismic Survey 2014, Roskilde Fjordforbindelsen. Rambøll, Rev 1, (see Contract Document G). The seismic investigations were limited to water depth of at least 1 m and comprised: Bathymetric measurements using multibeam echo sounder (MBES)

11 Establishment of seabed using Side Scan Sonar and localisation of abnormal objects at sea bottom (for instance cables). Sub Bottom Profiler to map the top of glacial sediment and internal post-glacial layers Magnetometer to detect anomalies Seismic investigations with GEP Sparker. For details about the investigation methods, reference is made to Rambøll Factual Report enclosed in Contract Document G (Datarapporter). The results of the investigation were summarized as follows Bathymetry The area covered by the main lines was limited to areas with a seabed depth of -1m DVR90 or deeper. Sea bed varies between -1 and -10 m DVR90 within the investigated area, however based on other investigations it is anticipated to have a greatest depth of approximately -7.5m DVR90. The deepest area corresponds to the N-S running fault through the centre of the Fjord. All depth references are given as m DVR Side Scan Sonar The following soil types were identified: Seaweed, Gyttja with shells, Excavation (uncertain sediment type) and Dunes (uncertain sediment type). Two seabed scars were identified and one unknown object. The Dunes identified could be build ups of sand deposits however the sonar indicated the sediment is similar to Gyttja with shells, thus the uncertainty in sediment type. Similarly, the Excavation is delineated by an increase in water depth and thus reveals deeper sediments not possible to classify by side scan sonar Magnetometer The magnetometer detected anomalies on the seabed however did not provide information as to their origins other than to determine their likelihood of being geological Seismic Profiling In general, the subsurface in the study area is characterized by glacial deposits at depths from -5 to -20m DVR90 which are covered by postglacial marine deposits. The limestone surface was interpreted and showed some good correlation with the boreholes carried out within the fjord, however it determined the depth to limestone in the centre of the fault as approximately 10m lower than identified in boreholes.

12 3.3 Geological Model Based on past geological, geotechnical and geophysical investigations, the following geological model has been established. It should be noted that the below given description of soil layers is based on limited information obtained from locations in the vicinity of the proposed bridge structure and must therefore be interpreted with care. It is expected that the site investigation contractor is familiar with Danish geology and has past experience in working in the expected soil types. The preliminary Ground Conceptual Model is enclosed as Drawing no. 2 of the Drawings Appendix (Tegningsbilag), and combines information from previous investigations including the geophysical survey. A summary of the geological strata is provided below. The information below is based on data currently available and is expected to be updated based on the results of this investigation. The information below and the preliminary Ground Conceptual Model have been provided for information only and the Contractor should not rely on the information contained within and below Limestone (prequaternary) The limestone surface along the proposed alignment of the Project is influenced by the Fjord fault where it causes a depression in the limestone surface. Within the fjord itself, the limestone surface reduces from approximately level -9.2m DVR90 to level -43.0m DVR90. Experience on other projects suggests that the Danish limestone is mainly composed of a carbonate mud with a variable content of flint either as nodules or layers. Its mechanical properties are largely determined, on a site specific basis, by the degree of induration and the degree and character of fracturing. The degree of induration is an expression of the degree of calcite cementation and silicification Glacial Deposits (quaternary) Moraine sediments were deposited in the form of clay, silt, fine to coarse sand and gravels. The thickness of these deposits range from 10 up to 25m on both sides of the Fjord, with greater variability observed within the Fjord itself. The recognised thickness of glacial deposits in the Fjord reaches about 1m in the central part (the lowest thickness) while in the eastern side of the Fjord, probably near the Roskilde Fjord fault, it reaches nearly 25m Late-glacial deposits When historically the Fjord was a large melt river, considerable amounts of late-glacial sediments in form of sands, gravels and locally clays and silts, were deposited. Therefore late glacial deposits were encountered in the Fjord area, the thickness of which varies from approximately 1m up to 12m.

13 3.3.4 Post-glacial Deposits Post-glacial deposits in the form of freshwater gyttja (mud), peat and shellbanks are present across the fjord. Within the post-glacial shellbanks, muds and peats, sands and clays were also deposited. The thickness of these post-glacial deposits varies between 1 and 10m. The lowest level of post-glacial deposits (where they exist) is approximately -15m DVR Geotechnical Parameters The previous investigations, along with historical data and literature on the soil types in the area, have been used to establish preliminary geotechnical parameters for the materials present. In most cases, direct calculation or assessment of the parameters was not possible, and have been estimated based on published correlations for the particular or similar soil types. These geotechnical parameters have been provided for information only and the Contractor should not rely on the information provided below.

14 August 2014 Scope of Works Niels Jorgen Larsen Table 1 - Preliminary Geotechnical Parameters Water content Plasticity index Bulk unit weight Hydraulic conductivity Effective Cohesion Undrained shear strength Young s modulus in drained conditions Young s modulus in undrained conditions Friction angle Preconsolidation pressure Material w PI γ k ϕ c c u E E u σ p [%] [%] [kn/m3] [m/s] [ ] [kpa] [kpa] [MPa] [MPa] [kpa] Topsoil *** - 25*** *** - Made Ground Peat * * 10-3 to 10-2 * * - Gyttja * 10-6 to 10-5 * 25-30* Shell Material Post-glacial sand * Late-glacial Sand to 10-1 *

15 Water content Plasticity index Bulk unit weight Hydraulic conductivity Effective Cohesion Undrained shear strength Young s modulus in drained conditions Young s modulus in undrained conditions Friction angle Preconsolidation pressure Material w PI γ k ϕ c c u E E u σ p [%] [%] [kn/m3] [m/s] [ ] [kpa] [kpa] [MPa] [MPa] [kpa] Late-glacial Clay to 10-4 * 33 (4<PI<7%)** 22 (20<PI<43)** 0 (4<PI<7%)** 7.2 (20<PI<43)** Glacial Cohesive Till (21.5)**** 10-7 to 10-5 * 33 (4<PI<7%)** 22 (20<PI<43)** 0 (4<PI<7%)** 9.0 (20<PI<43)** Glacial Cohesionless Till (20.5)**** Limestone (+) (*) value given in the COWI Technical Note supporting Phase 2; (**) value based on Sorensen & Okkels (2013); (***) provisionally assumed on the basis of experience; (****) suggested value; (+) highly dependent on the degree of fracture etc.

16 August 2014 Scope of Works Niels Jorgen Larsen Summary of Geological Model The geological formations along the high bridge route can be summarized as follows: Gyttja is generally found across the fjord seabed surface at thicknesses from near zero up to 10m. Shell banks are found on the western side of the fjord with thicknesses up to 5m. Post- and late-glacial deposits of sand, silt and clay are found in depths up to approximately 10m. Below, under gyttja and sand, there are glacial layers, mostly in the form of glacial till (moraine), but also in the form of melt water sand, silt and clay. The glacial layers are highly variable in composition. At -15m to -45m DVR90, limestone is encountered. The upper layer of the limestone is likely to be weathered. A graphical representation of the preliminary Ground Conceptual Model is provided in Drawing no.2 of the Drawings Appendix (Tegningsbilag). 4. PROGRAMME OF GEOTECHNICAL INVESTIGATION This section describes geotechnical field and laboratory tests to be carried out. Geotechnical investigations shall use a combination of the following techniques: Coring and sampling. Down the hole geophysics in the limestone. In-situ testing for accurate stratification and determination of engineering parameters: CPTu in all investigation locations, seismic flat dilatometer testing, Field Vane Test (FVT) and SPT where appropriate Routine laboratory testing where index properties and engineering parameters shall be determined. Advanced laboratory testing for determination of strength and deformation properties. An indicative graphical programme of testing in each borehole is provided in Appendix C and the final schedule of testing will be decided on site in agreement with the Engineer and VD Representative. 4.1 VD Representative VD reserves the right to send an Engineer or Representative to attend the data collection in the field / on board and to observe the progress and continually in cooperation with the Contractor to optimize data quality or to take the decision to put the investigations on hold due to weather, waves or other circumstances beyond the Contractor s control. VD reserves the right to discard tests that are sub-standard and have them redone at no cost.

17 4.2 Particular borehole requirements As the method of drilling will be proposed by the Contractor, a number of particular requirements have been highlighted here, relevant to different types of encountered soil/rock formations. The relevant information below will be valid based on the final method chosen. Boreholes over water shall be advanced to penetrate the limestone bedrock by 10m or the depth anticipated in Table 2 has been reached. Boreholes on land shall be advanced to penetrate the limestone bedrock by 5m. The minimum nominal casing diameter shall be 200 mm. At ground level before boring commences, the initial casing diameter shall be sufficiently large to ensure that the borehole can be completed to its scheduled depth. Rotary core drilling shall produce cores of circular cross section not less than 102mm diameter throughout the core length. The type and state of drill bit, feed rates and management of the drill shall be such that 100% core recovery in any single run can be obtained where the condition of the rock permits. Core recovery less than 90% in any drill run will not normally be acceptable unless the Engineer is satisfied that a greater recovery than 90% is impractical under the prevailing conditions. The Engineer is to be informed when core recovery is less than 90%. When any recovery is less than 90% from a drill run then the next drill run shall be reduced to 50% of the previous length, unless otherwise agreed by the Engineer, and so on down to a minimum length of 0.5 m. This procedure will be followed during drilling. Open hole ODEX or rotary percussive drilling may be carried out where core drilling proves ineffective or is instructed by the Engineer. Where required by the Contract, or where requested by the Engineer, SPT's shall be carried out. All coring rigs shall be capable of performing SPTs. Depth shall be indicated on the core box by durable markers of a type approved by the Engineer at one metre intervals and at all significant changes of strata and at the end of each drill run. Where there is failure to achieve recovery, the core boxes shall be labelled to indicate what depth and quantity the core loss occurred. The location, exploratory hole number and the depth of coring relating to the contents of each box shall be clearly indicated in indelible ink on labels, inside the box, on the top and on each end of the box. All markers and labels shall be such as to facilitate subsequent photography. Boreholes on land shall be backfilled with cement/bentonite grout. All cores shall be transported to the Contractors premises and stored in a protected, secure, dry storage space for a minimum period of 12 months after completion of the final factual report. The cores shall be stored in such a fashion that all cores shall be easily accessible for viewing. After this period the Contractor shall carefully deliver all cores to VD s premises at a location directed by the VD Representative.

18 Access for the inspection of the cores by the VD Representative or Engineer shall be provided by the Contractor for the duration of the Contract. All core boxes used to store core shall become property of VD. In addition to the requirements of the Specification, the Contractor shall photograph cores where required in fresh condition prior to logging, preferably on the day of recovery, but always within a maximum of 72 hours of recovery. All cores shall be photographed with a colour and grey scale (e.g. Kodak), appropriate liner scale and depth notations. Each core box shall be represented on a 175mm x 125mm sized photograph. Where boulders, rock and other hard strata are encountered, percussion boring using a chisel shall take place in an attempt to penetrate the obstruction and break it up sufficiently for fragments to be recovered and identified. A detailed record shall be kept of the time spent chiselling and the rate of penetration through the obstructing object. The maximum time spent chiselling at any one obstruction shall be two hours unless expressly permitted by the Engineer or VD Representative. Where artesian water is encountered the Contractor shall immediately inform the Engineer and shall attempt to contain the artesian head by extending the casing above the existing ground surface by a maximum of 1 m. Where an artesian head greater than 1 m above ground surface is encountered the Contractor shall cap the boring and fit a pressure gauge and by-pass to measure the pressure head of the artesian water. 4.3 Identification of Testing Methods The following abbreviations will be used in this document and the Bill of Quantities (Tilbudsliste) to identify field investigation methods: BH CPT CPTu sdmt RQD SPT VST FVT Borehole. Cone Penetration Test. Cone Penetration Test with pore water pressure measurement (Piezo-cone Penetration Test). Seismic Flat Dilatometer test. Rock Quality Designation. Standard Penetration Test. Lab Vane Shear Test. Field Vane Test The following abbreviations will be used in the document to identify laboratory investigation methods: CID CIU UU CAU/CK0U CAD/CK0D DSS ILOed Isotropically consolidated, drained triaxial compression / extension. Isotropically consolidated, undrained triaxial compression / extension. Unconsolidated, undrained triaxial compression. Anisotropic/K0 consolidated undrained triaxial compression. Anisotropic/K0 consolidated drained triaxial compression. Direct simple shear test. Incrementally Loaded Oedometer test

19 Planning, execution and documentation of field and laboratory tests shall comply with Eurocode 7 Part 2, incorporating DK NA: It is important that all equipment used during the course of the investigations is in excellent operating condition. All electronic and mechanical devices shall be calibrated prior to their use and relevant certificates provided to the VD Representative. 4.4 Geological Profiles The geological profiles which can be expected have been described in Section 3.3. It is important that appropriate investigation methods (or a combination of different methods) are used to obtain the required information. 4.5 Test Locations and Testing Depth The final layout of the bridge structure and thus of the foundation locations is not decided yet. Therefore, it is proposed that offshore investigations be carried out for the bridge structure according to Drawing no. 2 of the Drawings Appendix (Tegningsbilag) and the arrangement depicted in Figure 3. Based on the previously performed investigations discussed in previous sections, the following information has been interpreted for the borehole of this GI, cf. Table 2. The identification of investigation points (ID No.) is based on the bridge span width as shown in Figure 2. Table 2 - Estimated seabed level, water depth, depth to top of limestone and soil layer thickness. Borehole ID Estimated Seabed level [mdvr90] Estimated Water depth [m] Estimated Level of top of Limestone [mdvr90] Estimated Soil Layer Thickness [m] BHA1 land boring BH1 land boring BH BH BH BH BH BH BH BH BH BH BH BH BH BH BH BH17 land boring Required penetration of limestone [m]

20 Borehole ID Estimated Seabed level [mdvr90] Estimated Water depth [m] Estimated Level of top of Limestone [mdvr90] Estimated Soil Layer Thickness [m] BH18 land boring BHA2 land boring Required penetration of limestone [m] It should be noted that this information is given for guidance only and actual values may deviate from those given in Table 2. At each investigation location, the sampling and testing shall be carried out according to the following tentative scheme: Identification of test location. Determination of position and elevation. Start and termination time of each test. Measurement of water depth (to seabed). Standard penetration tests (SPT). Static penetration tests (CPTu) with two pore water pressure dissipation tests per CPTu location. Seismic flat dilatomer tests (sdmt) at selected locations. Boring and/or coring. Sampling of soil and/or rock. As stated above, all tests shall be performed according to most recent versions of EN standards, see Appendix A, CEN ISO/TS Standards - Geotechnical Investigation and Testing. In Figure 3, the tentative arrangement of tests in each test location is shown. Figure 3 - Arrangement of investigation locations.

21 4.6 In-situ Testing It is important that all test data are evaluated and interpreted on site in order to verify that the anticipated data have been obtained. All data shall be stored electronically and made available in AGS format. Details for each test are provided below PiezoCone Penetration Testing (CPTu) In general, and unless not practicable, it is recommended to start investigations in each test location with the Seabed CPTu test. The tests are likely to penetrate through the soft and medium stiff soil layers. The minimum depth of cone penetration shall be to the weathered limestone. If refusal is reached at shallower depths than required, in the glacial till for example, the contractor shall carry out the borehole for that location. The contractor will then carry out a downhole CPTu, the termination depth of which will be informed by the depth to bedrock determined from the borehole. The downhole CPTu tests will be started every 1.5m. The contractor shall check and record the base of the cone following each of these pushes and record any residual material attached to it as an indication of the termination material, the cone shall be cleaned after each test. The rated capacity of the Seabed and downhole CPT equipment shall be 20 tonnes unless otherwise agreed. Two pore water pressure dissipation tests shall be carried out per CPTu location to establish the ground water conditions and pore water pressure distribution in different soil formations. Considering the moderate water depth it is considered that conventional penetration testing equipment can be used at most test locations. However, specialized CPT equipment has been developed for off shore investigations at greater water depth. Reference is made to the ISSMGE TC 1 Guidance document mentioned in section Standard Penetration Tests (SPT) Standard Penetration Tests will be carried out every 0.5m at the locations of the land boreholes. These will be carried out to a depth of 20m, or may be terminated at a shallower depth upon instruction from the Engineer. They will only be carried out in cohesionless material Field Vane Tests (FVT) Field Vane Tests will be carried out every 1m in cohesive material encountered during the investigations. Reference is made to DGF Bulletin 14 Felthåndbogen for the procedure to be followed for the execution of this test.

22 4.6.4 Seismic Flat Dilatometer (sdmt) Flat dilatometer testing with shear wave velocity measurements will be carried out at selected locations on land and/or over water. An indicative location of these tests is shown in the graphical borehole programme provided in Appendix C. Reference is made to ISSMGE TC 16 Guidance document on The Flat Dilatometer Test (DMT) in Soil Investigations (2001) and to ASTM D Standard Test Methods for Downhole Seismic Testing for the procedures to be followed for the execution and reporting of these tests. An underwater seismic hammer shall be deployed for the generation of the energy source at investigation locations over water. 4.7 Downhole geophysical logging Downhole geophysical logging in the limestone is required in all boreholes in accordance with international best practise and BS A minimum of the following data shall be collected: Dummy probe to confirm depth and stability of boring Natural gamma Density / porosity Focussed resistivity Calliper Temperature / conductivity Flow logs 4.8 Soil and Rock Sampling General Soil and rock samples shall be obtained from each geological formation in order to provide representative information of soil and rock layers. Depending on soil type, undisturbed (cohesive soils) and disturbed soil samples shall be obtained. The preparation for, frequency, and method of taking samples, together with their size, preservation and handling shall be in accordance with the recommendations of DGF Bulletin 14 Felthåndbogen and the requirements of EN ISO The Contractor shall supply to the Engineer, on a daily basis, a list of the samples taken from each exploratory hole. The information shall be presented in a table format with the sample details (BH, depth, type etc.) given in a vertical column on the left hand side of the table and a list of possible laboratory tests given in a horizontal row at the top of the table. The laboratory tests to be undertaken on all collected samples will have to be agreed upon with the Engineer.

23 Disturbed and high quality samples are required to be taken from the boreholes for the purposes of geotechnical testing. In boreholes alternating samples and bulk samples at 1 m intervals will be recovered in the sea bed sediments and fine grained till deposits starting with a bulk sample at the top of the deposit. Small disturbed samples to be taken at each change in soil type or consistency and with each bulk sample in cohesive soil. Grab samplers are one of the most common methods of retrieving soil samples from the seabed surface. Grab samplers can be used to recover samples of most seabed soils, although care is needed in selecting the right size unit for the task. The information they provide, although coarse, can be applied in a number of applications such as: Bulk sampling for seabed material identification Environmental sampling Pre-dredge investigations Soil identification for morphological mapping and verification of geophysical surveys. Grab samples will be taken at each of the offshore investigation locations, within 10m of the bridge centre line. The contractor may select the drilling method and equipment to obtain the specified samples, provided the methodology is outlined in the tender submission. Where artesian conditions are encountered, the Contractor shall inform the Engineer and consult and agree with him the measures to be taken. Samples of seawater shall be taken at locations specified by the Engineer Sampling Equipment For the drilling of boreholes, it is recommended that all drilling be carried out with a Geobor S rig. Experience in the region would indicate that core samples can be retrieved from the medium to stiff soil deposits as well as the limestone rock. However, where core samples are not retrievable (such as in the very soft top layers of material, or in the gyttja), conventional shell and auger drilling with piston samples is recommended. The sampling equipment shall be to the approval of the VD Representative and the Engineer. The Contractor shall state in his Tender the make and type of sampler he proposes to use. The Contractor shall also state in his Tender the range of soil strengths in which the system proposed can be used. The object is to obtain samples that are as nearly undisturbed as possible. The sample tubes shall be of a minimum length of 600mm and shall have a minimum internal diameter of 100mm (UT100 or equivalent). Tubes shall be made of steel or aluminium. Plastic lining tubes shall not be used in substitution for steel or aluminium sampling tubes. Tubes should possess a sharp cutting edge and provide suitable inside clearance.

24 The interior of each sample tube shall be smooth, clean and resistant to corrosion. The cutting edge and the ring seals of the sampler (if any) shall be inspected for wear or evidence of any damage and rejected if worn or damaged. The interior face of the tube shall be parallel and the tube's area ratio (as referenced in EN ISO :2006) shall lie in the range 10 to 15%. The tube should be lightly coated inside and out with either petroleum jelly or vegetable oil before use. The Contractor shall state which he intends to use prior to commencement of site works. A check shall be made that the various moving parts of the sampler function freely before the sampler is lowered into the borehole Supervision When in use the piston sampler or thin-wall sampler shall be under the direct supervision of an experienced technical assistant from the Contractor's staff who is fully experienced in its use. The rig operator may take this role if suitably experienced in the sampling technique involved Pushing the Sampler For both piston sampling and thin-wall sampling, accurate measurement of the depth from which each sample is recovered, the length of sampling stroke and the length of sample recovered shall be made and recorded. If an obstruction is met the sampler shall be withdrawn and another sample taken when the obstruction has been removed. Immediately on completion of the sample stroke the sampler shall be withdrawn from the ground and the sample tube shall be separated from the sampler. Precautions shall be taken to ensure that there is no movement of the sample inside the sample tube or other mechanical disturbance. Any distortion or damage of the sampling tube greater than 1mm shall be noted. On the instruction of the Engineer, a hand vane test shall be carried out in the top and bottom of each sample prior to sealing. The Contractor shall push the sampler down to the intended sampling levels if this is practical. The sampler shall be advanced a minimum of 0.30m below the bottom of the boring before sampling commences. The sampler shall be pressed down smoothly and continuously whilst the piston is firmly secured so that it remains stationary. The tubes shall be advanced into the clay by hydraulic means in a continual push over a period of between 10 minutes and 30 minutes. The time taken shall be recorded. The sample tube shall be left in the ground for a further 5 minutes and then withdrawn vertically without shear-

25 ing the sample base by rod rotation. A means for measuring the exact penetration of the tube and the maximum thrust achieved shall be provided Sampling of Soft Soils For recovery and high sample quality appropriate equipment/methods shall be used in soft soils. Unless recovery of a quality Class 1 soils sample in accordance with EC7-2 is possible with a Geobor S rig, conventional shell and auger drill methods with piston sampling or thin walled sampling shall be employed. Samples from piston corers allow for recovery of better quality samples in accordance with EC7-2. Piston samples are to have a 100 mm internal diameter. Sample tubes shall be brand new (unused), made of steel or aluminium, plastic lining tubes shall not be used in substitution for steel or aluminium sampling tubes. The piston sampler shall have a cutting edge of 5º and soil samples shall be at least 300mm long. Piston samples are to be double sealed with wax, adhesive tape and caps after a visual description and vane tests have been undertaken. Piston samples are to be stored and transported in an upright position. Transport containers shall be constructed in such a way that each sample is isolated and padded to minimise disturbance from vibration. Where piston samplers cannot be used, thin walled push-samplers of minimum diameter 70mm should be used Medium to Stiff Soils (Glacial moraine) In medium to stiff clays, coring is required. Recovery is required to be at least 90%. If core loss is greater than 10% in any run, the subsequent runs lengths must be halved. If, after halving the subsequent run s length core loss is still greater than 10% the sampling method may be changed, pending the Engineer s approval. It may be preferable that sampling is completed with piston samplers. When piston samplers cannot be used, thin walled push-samplers (minimum diameter 70mm) should be used following the criteria outlined in section When this is not possible, as in dense sand, hammer samplers may be used. Installation by hammering in a shallow water environment may use rods. Wire-line down-hole hammers can be used in greater water depths. Sample hammer blow-counts from such samplers generally do not correlate with SPT data largely due to energy losses. In some cases, such as in boulder clays or soils containing stones and boulders, rock-coring techniques may be necessary Rock Coring In the transition zone from soil to rock, it can be expected that rock fragments are encountered. Also, the top layer of the limestone is likely to be fractured. It is important that rock samples are obtained to a depth of 10 m into the intact limestone layer. It is vital to this project that the weathered/fractured zone of the limestone is sampled and delineated.

26 If core loss is greater than 10% in any run, subsequent runs must be half the length. Underwater rotary rock corers can be used to recover undisturbed core samples of harder soils and rock, usually in shallow water. In order to recover a high quality and undisturbed core sample, the core tube has to be static. Rotary rock corers are designed as double or triple tube devices where the innermost tube acts as a core liner, the middle tube, if present, acts as a holder and the rotating outer tube carries the hollow drill bit. As the bit cuts down through the soils and rock, the core created passes into the liner in a relatively undisturbed state Handling of Soil and Rock Samples The sample handling and laboratory works shall include: Precautions shall be taken to ensure that there shall be no change in the moisture content of the sample after it is obtained. A small amount of melted low melting point wax shall be poured over each end of the sample and a wax sealing disc laid in the wax within 30 minutes of the sample being removed from the ground. When the wax has stiffened more wax shall be added to complete the seal. Any space between the wax and the ends of the sample tubes shall be packed and secure end caps fitted. The sample shall be clearly labelled with the project name, borehole number, sample number and sample depth. The top of the sample shall also be clearly labelled. The Contractor's technical assistant responsible for the supervision of the sampling shall complete a record sheet, such as that included in Table C1. This shall be submitted with the driller's daily record sheet. Table C1: Record Sheet