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Glanbia Doc No IE0310818-22-RP-0001 Issue A Project Purple 2 05 July 2012

ATTACHMENT 3

SUMMARY REPORT ON GEOPHYSICAL SURVEY

BY APEX GEOSERVICES LTD.

AGL12083_01

REPORT ON THE

GEOPHYSICAL SURVEY

AT

PROJECT PURPLE

FOR

IGSL

APEX Geoservices Limited Kilanerin Gorey Co. Wexford T: 0402 21842 F: 0402 21843 E: [email protected] W: www.apexgeoservices.com

17TH MAY 2012

AGL12083 Project Purple Geophysical Report May 2012

PRIVATE AND CONFIDENTIAL

THE FINDINGS OF THIS REPORT ARE THE RESULT OF A GEOPHYSICAL SURVEY USING NON-INVASIVE SURVEY TECHNIQUES CARRIED OUT AT THE GROUND SURFACE. INTERPRETATIONS CONTAINED IN THIS REPORT ARE DERIVED FROM A KNOWLEDGE OF THE GROUND CONDITIONS, THE GEOPHYSICAL RESPONSES OF GROUND MATERIALS AND THE EXPERIENCE OF THE AUTHOR. APEX GEOSERVICES LTD. HAS PREPARED THIS REPORT IN LINE WITH BEST CURRENT PRACTICE AND WITH ALL REASONABLE SKILL, CARE AND DILIGENCE IN CONSIDERATION OF THE LIMITS IMPOSED BY THE SURVEY TECHNIQUES USED AND THE RESOURCES DEVOTED TO IT BY AGREEMENT WITH THE CLIENT. THE INTERPRETATIVE BASIS OF THE CONCLUSIONS CONTAINED IN THIS REPORT SHOULD BE TAKEN INTO ACCOUNT IN ANY FUTURE USE OF THIS REPORT.

PROJECT NUMBER AGL12083

AUTHOR CHECKED REPORT STATUS DATE

EURGEOL SHANE O`ROURKE P.GEO., M.SC (GEOPHYSICS)

EURGEOL PETER O’CONNOR P.GEO., M.SC (GEOPHYSICS), DIP.

EIA MGT. V.01 17TH MAY 2011

Geophysical Investigation, Project Purple for IGSL

1 AGL12083 Project Purple Geophysical Report May 2012

CONTENTS

1. EXECUTIVE SUMMARY ................................................................................................................ 3 2. INTRODUCTION ............................................................................................................................ 4

2.1 Survey Objectives ....................................................................................................................... 4 2.2 Site Background ......................................................................................................................... 4

2.2.1 Topography ............................................................................................................................................... 4

2.2.2 Geology .................................................................................................................................................... 4

2.2.3 Soils & Vulnerability ................................................................................................................................. 6

2.2.4 Trial Pits ................................................................................................................................................... 6

2.3 Survey Rationale ........................................................................................................................ 7 3. RESULTS & INTERPRETATION ................................................................................................... 8

3.1 Seismic Refraction Profiling ....................................................................................................... 8 3.2 MASW Results........................................................................................................................... 8 3.3 Conductivity Mapping .............................................................................................................. 10 3.4 2D Electrical Resistivity Tomography (ERT) ........................................................................... 11 3.5 Discussion ............................................................................................................................... 11 3.5.1 Overburden ............................................................................................................................... 11

3.5.2 Bedrock .................................................................................................................................................. 12

3.5.3 Bedrock Depth ....................................................................................................................................... 12

3.5.4 Fault ....................................................................................................................................................... 13

4. RECOMMENDATIONS ............................................................................................................... 14 5. REFERENCES ............................................................................................................................ 15 6. APPENDIX A: DETAILED METHODOLOGY ............................................................................. 16

6.1 Seismic Refraction Profiling ..................................................................................................... 16

6.1.1 Principles ............................................................................................................................................... 16

6.1.2 Data Collection ...................................................................................................................................... 16

6.1.3 Data Processing ..................................................................................................................................... 16

6.1.4 Relocation .............................................................................................................................................. 16

6.2 MASW ...................................................................................................................................... 16

6.2.1 Principles ............................................................................................................................................... 16

6.2.2 Data Collection ...................................................................................................................................... 17

6.2.3 Data Processing ..................................................................................................................................... 17

6.2.4 Relocation .............................................................................................................................................. 18

6.3 Electrical Resistivity Tomography (ERT) ................................................................................. 18

6.3.1 Principles ............................................................................................................................................... 18

6.3.2 Data Collection ...................................................................................................................................... 18



6.3.3 Data Processing ..................................................................................................................................... 19

6.3.4 Relocation .............................................................................................................................................. 19

6.4 Ground Conductivity Mapping ................................................................................................. 19

6.4.1 Principles ............................................................................................................................................... 19

6.4.2 Data Collection ...................................................................................................................................... 19

6.4.3 Data Processing ..................................................................................................................................... 20

6.4.4 Relocation .............................................................................................................................................. 20

7. APPENDIX B: MASW RESULTS ................................................................................................ 21 8. APPENDIX C: DYNAMIC MODULI ............................................................................................. 25 9. APPENDIX D: SEISMIC REFRACTION PLATES ....................................................................... 29 10. APPENDIX E: DRAWINGS .......................................................................................................... 30



1. EXECUTIVE SUMMARY

APEX Geoservices Limited was requested by IGSL, on behalf of PM Group, to carry out a geophysical investigation as part of the ground investigation at the Project Purple site near Belview, Co. Kilkenny.

The objectives of the survey were to assess the depth to bedrock and the weathering and excavatability of the bedrock, and to identify the type of bedrock & overburden, as well as any possible karst development and soft zones.

The investigation consisted of Seismic Refraction Profiling, MASW Profiling (Multichannel Analysis of Surface Waves), Conductivity Mapping and 2D Electrical Resistivity Tomography (ERT).

The site comprised 20Ha of grassland with a wetlands area in the north‐east of the site, with the rock type comprising rhyolitic volcanics and grey slates. Karst features will not be an issue in this rock type.

The results indicate that overburden comprises mainly sandy gravelly clay, with silt/clay in the north‐east and some sand/gravel pockets. Overburden is generally firm‐very stiff / medium dense – very dense throughout.

MASW Profiling indicates firm‐very stiff material in the area of the main building footprint.

The proposed building footprint is located across the transition from shallow volcanic bedrock in the south to deeper meta‐siltstones and shales in the north.

Bedrock has been interpreted as thin (0.5‐1.0m) moderately siltstone/slate (which will be marginally rippable to requiring breaking/blasting) and slightly weathered‐fresh siltstone/slate (requiring breaking/blasting) in the area of the buildings and the north and east of the site. Rhyolite has been in interpreted in the south and west of the site.

Bedrock depth has been interpreted as 1.5‐2.5m in the south of the field with the planned main building, falling to 11m bgl in the north of this field. The remainder of the site includes a zone of shallow rock (0.5‐3.5m bgl) in the centre of the site, surrounded by deeper (3.5‐6.0m) rock, with rock >6.0m bgl throughout the north of the site.

The excavation of the building footprint will encountered changing overburden and bedrock condition from south to north. Permeabilities of the volcanic and metamorphosed rocks, where encountered, are likely to be higher than the shale/mudstones.

A possible NE‐SW fault with an offset to the SE has been interpreted through the centre of the site.



2. INTRODUCTION

APEX Geoservices Limited was requested by IGSL., on behalf of PM Group, to carry out a geophysical investigation as part of the ground investigation at the Project Purple site near Belview, Co. Kilkenny.

2.1 Survey Objectives

The objectives of the survey were to:

1. Assess the depth to bedrock and the weathering and excavatability of the bedrock

2. Identify the type of bedrock

3. Provide information on the type and thickness of the overburden

4. Estimate the overburden stiffness values

5. Identify any karst zones or fissure/fault zones in the bedrock.

2.2 Site Background

The site is located 700m north‐west of Belview Port, Co. Kilkenny, and comprises gently undulating grassland. A wet marshy area is present in the north‐east of the site. An industrial zone is planned to be built on site. The site is surrounded by roadway to the north, east and west and by grassland to the south. The river Suir estuary is located 500m south of the site.

2.2.1 Topography

The topography of the site slopes gently from approx. 30 mOD in the north of the site to approx. 15.5mOD in the south of the site.

2.2.2 Geology

The GSI Bedrock Geology map for the area indicates that the site is mainly underlain by rhyolitic volcanic and grey and brown slates of the Campile Formation, with felsic volcanics of the Campile Formation in the south‐west of the site. A fault runs through the site from SW‐NE. There are no karstic weathering features in these rock formations.



Fig.2.1. Geological map for the site.

Fig.2.2. Soils map for the site.



2.2.3 Soils & Vulnerability

The Teagasc soils map for the area shows that the site comprises Devonian sandstone till, with the wetlands area comprising alluvium. The vulnerability for the area (Figure 2.3) ranges from low in the north‐east to high in the south‐west.

2.2.4 Trial Pits

No. 36 trial pits have been opened by the client on site and the results have been made available to assist with the geophysical interpretation.

The results generally indicate overburden comprising firm‐very stiff sandy/silty gravelly clay with occasional lenses of coarse gravel or sandy silt/clay.

No. 18 trial pits were conducted in the field where the main building is planned (Figure 12083_01), and these have been opened to 4.0m bgl without reaching bedrock with the exception of four trial pits in the south of the field which recorded probable weathered rock (metamorphosed mudstone/siltstone) at 2.5‐3.1m bgl.



TP24 (metamorphosed mudstone/siltstone at 1.5m bgl) to the south of the planned main building) and TP22 (metamorphosed mudstone/siltstone at 2.5m bgl) at the main gate to the east, also recorded bedrock.

Five of the remaining trial pits recorded probable weathered rock (rhyolite volcanic rock) in the west of the site at 1.7‐2.3m bgl.

2.3 Survey Rationale

Seismic Refraction Profiling measures the velocity of refracted seismic waves through the overburden and rock material and allows an assessment of the thickness and quality of the materials present to be made. Stiffer and stronger materials usually have higher seismic velocities while soft, loose or fractured materials have lower velocities. Readings are taken using geophones connected via multi‐core cable to a seismograph. This method will allow us to profile the depth to the top of the bedrock, along profiles across the site.

Electrical Resistivity Tomography (ERT) soundings will image the resistivity of the materials in the subsurface along a profile to produce a pseudo‐section showing the variation in resistivity to 30m bgl. Each pseudo‐section will be interpreted to determine the material type along the profile at increasing depth, based on the typical resistivities returned for Irish ground materials.

Conductivity Mapping measures the same geophysical property as ERT, and in this case materials with a low resistivity will have a high conductivity. Conductivity mapping is carried out using an EM31 Conductivity Meter, which is carried across the ground in set pattern, to provide conductivity values for the materials from 0 – 6.0m bgl.

The MASW method is used to estimate shear‐wave (S‐wave) velocities in the ground material to indicate possible soft zones. Overburden material with an S‐wave velocity of <175 m/s is generally classified as soft. The depth of investigation for this method will depend on the source type and geophone spacing. In this survey an effective depth of investigation of 1.3‐18.9m bgl was achieved.



3. RESULTS & INTERPRETATION

3.1 Seismic Refraction Profiling

Four seismic refraction spreads (Profiles S1‐S4) were recorded throughout the site. Each of the profiles was 46m in length and has a depth of investigation of approx. 16m.

The seismic data has outlined four velocity layers and has been generally interpreted on the following basis:

Layer Seismic

Velocity (m/s) Average Seismic Velocity (m/s)

Thickness (m) Interpretation Stiffness/Rock Quality Excavatibility

1 229‐641 347 0.6‐1.6 Overburden Soft‐Firm / Loose‐Medium Dense

Diggable

2 735‐1159 954 0.1‐3.6 Overburden Firm‐Stiff / Medium

Dense‐Dense Diggable

3 1333‐2135 1656 0.9‐13.4

Overburden Stiff‐very Stiff /

Dense‐Very Dense Diggable

Highly‐Moderately Weathered Bedrock

Fair Marginally Rippable – Break/Blast

4 2782‐3454 3066 Slightly Weathered –

Fresh Bedrock Good Breaking/Blasting

3.2 MASW Results

MASW processing has been carried out for Profiles S1‐S4.

The processed shear wave velocities (Fig.3.1) range from 207 – 798 m/s (average of 490 m/s) for material interpreted as overburden, with a corresponding Gmax (Fig.3.2) of 91 – 1272 MPa (average of 565 MPa). These velocities generally indicate overburden which is firm‐very stiff / medium dense–very dense (Figure 3.3), and do not indicate the presence of soft zones.

For the field which is planned to comprise the main building, the velocity profiles indicate that the overburden material to the south of the field (Profiles S1 & S4) is generally stiffer than the material to the north (Profiles S2 & S3).



0

2

4

6

8

10

12

14

16

18

20

0 200 400 600 800 1000 1200 1400 1600

Dep

th (m

)

Fig.3.1 Shear wave Velocity, Vs (m/s)

S1

S2

S3

S4

0

2

4

6

8

10

12

14

16

18

20

0 1000 2000 3000 4000

Dep

th (m

)

Fig. 3.2 Calculated Gmax Values (MPa)

S1

S2

S3

S4



Fig.3.3. Shear‐wave velocity and corresponding soil cohesion.

3.3 Conductivity Mapping

The conductivity results are indicative of the bulk conductivity of the ground materials from 0‐6.0m bgl and have been generally interpreted as follows:

Conductivity (mS/m)

Interpretation

1.0 – 4.5 0.5‐3.5m of sandy gravelly CLAY followed by bedrock

4.5 – 6.0 3.5‐6.0m of sandy gravelly CLAY followed by bedrock

6.0 – 10.0 >6.0m of sandy gravelly CLAY

10.0 – 12.0 >6.0m of SILT/CLAY

12.0 ‐ 16.0 Influenced By Metal

These results are discussed in Section 3.5.1 below.



3.4 2D Electrical Resistivity Tomography (ERT)

2‐D ERT Profiles R1‐R7 have been acquired across the site (Drawing 12083_01). The profiles have been interpreted on the following basis (Drawing 12083_01):

Resistivity (Ohm.m) Interpretation

80 ‐ 250 Sandy gravelly CLAY

250 ‐ 806 clayey SAND/GRAVEL

160 ‐ 320 SLATE

250 ‐ 320 Weathered SILTSTONE

320 ‐ 1280 SILTSTONE

250 ‐ 320 Weathered RHYOLITE

320 ‐ 1280 RHYOLITE

Note that Profiles R8 and R9 are influenced by services and have not been interpreted.

3.5 Discussion

3.5.1 Overburden

Material with resistivities of 80‐250 and 250‐806 Ohm‐m has been interpreted as sandy gravelly clay and clayey sand/gravel respectively.

Sandy gravelly clay is by far the most abundant soil type throughout and this is confirmed by the trial pits. Occasional lenses of clayey sand/gravel have also been interpreted.

The conductivity results confirm that sandy gravelly clay is abundant throughout. A zone of silt/clay (>6.0m thick) has been interpreted from the conductivity results in the north‐east of the site in the wetlands area, which coincides with the zone of alluvium on the Soils map above.

Layer 1 for the seismic refraction results indicates soft‐firm / loose‐medium dense overburden from 0.6‐1.6m bgl (in the area of the planned main building where seismic refraction profiling has taken place).

Layer 2 indicates firm‐stiff / medium dense‐dense overburden to a depth of 0.9‐4.6m bgl.

Layer 3 indicates stiff‐very stiff / dense–very dense overburden followed by moderately bedrock.



3.5.2 Bedrock

Bedrock with a resistivity of 160–320 and 320‐1280 Ohm‐m in the north and east of the site has been interpreted as slate and siltstone respectively. Near‐surface material in the north and west of the site has been interpreted as weathered siltstone.

Bedrock with a resistivity of 250–320 and 320‐1280 Ohm‐m in the west of the site has been interpreted as weathered rhyolite and rhyolite respectively.

This subdivision of the bedrock types is based on the resistivity results, the trial pit results and the geological map for the site.

Moderately weathered siltstone/slate has been interpreted for Profiles R2 and R3 in the area of the planned main building. This material has been interpreted for the southern part of this field with a thickness of approx. 0.5‐1.0m. The seismic refraction results indicate that this material will be marginally rippable to requiring breaking blasting.

Slightly weathered to fresh siltstone has been interpreted as underlying this material and this will require breaking / blasting upon excavation.

Slightly weathered to fresh slate has been interpreted at slightly greater depths in the north of this field (Profiles R1‐R3), and this material will also require breaking / blasting upon excavation.

Weathered rhyolite has been interpreted for Profiles R5‐R7 in the south and west of the site, with a thickness of approx. 0.5‐3.5m. The results for Profiles R6 and R7 indicate that zones of variable weathering of the rhyolite will be present in the south and west of the site. This may result in the development of corestones (fresh unweathered bedrock alongside zones of completely weathered bedrock). One of these areas is targeted for further investigation below.

Slightly weathered to fresh rhyolite has been interpreted as underlying this material.

3.5.3 Bedrock Depth

Overall bedrock depth in the area of the planned main building is interpreted to increase to the north (Drawing 12083_04), with bedrock depth at 1.5‐2.5m in the south of the field and up to 11m in the north of the field.

The conductivity results (and Profiles R4‐R7) may be used to indicate the depth to rock across the remainder of the site. These results (Drawing 12083_03) indicate that a zone of shallow rock is present in the centre of the site, with rock depth interpreted as 0.5‐3.5m bgl. This is surrounded to the north and south by an area with an interpreted rock depth of 3.5‐6.0m bgl. The northern one‐third of the site is then interpreted to comprise bedrock which is >6.0m bgl (and up to 11m bgl, see above). A small area of deeper bedrock is also interpreted for the far south of the site.



Due to the very similar resistivities between slate and sandy gravelly clay confirmatory drilling is required to confirm the bedrock depth in the north of the field where the main building is located.

The excavation of the building footprint will encountered changing overburden and bedrock condition from south to north. Permeabilities of the volcanic and metamorphosed rocks, where encountered, are likely to be higher than the shale/mudstones.

3.5.4 Fault

As noted on Fig 2.1 SW‐NE fault are present on the GSI map running through the site and enclosing a wedge of volcanic bedrock. The geophysics and trial pit data indicate that the volcanic rock is more extensive in the south and centre of the site and a possible SW‐NE fault has been interpreted running along the north‐western side of the volcanics. An offset of this possible fault to the SE is also shown on Maps 12083_03 and 12083_04.



4. RECOMMENDATIONS

The following boreholes (Drawing 12083_03) are proposed to confirm the geophysical results. The report should be revised after the completion of the direct investigation.

Borehole Easting Northing Target / Depth

PBH1 264760.0 113202.4 Rock depth / type. To 25m

PBH2 264702.0 113130.4 Rock depth / type. To 10m

PBH3 264772.6 112981.8 Possible fault. To 15m

PBH4 264971.2 112933.9 Possible completely weath. rock. To 15m

PBH5 264559.6 112821.3 Possible completely weath. rock. To 15m

PBH6 264760.0 113250 Rock depth / type. To 20m

Where bedrock excavation is proposed a detailed assessment of excavatability should be carried out combining the results of the geophysical survey, rotary core drilling, strength testing, and trial excavation pits using a high powered excavator.



5. REFERENCES

Bell F.G., 1993;

‘Engineering Geology’, Blackwell Scientific Press.

Campus Geophysical Instruments, 2000;

‘RES2DINV ver. 3.4 Users Manual’, Birmingham, England.

Hagedoorn, J.G., 1959;

‘The plus ‐ minus method of interpreting seismic refraction sections’, Geophysical Prospecting, 7, 158 ‐ 182.

Palmer, D., 1980;

‘The Generalized Reciprocal Method of seismic refraction interpretation’, SEG.

Redpath, B.B., 1973;

‘Seismic refraction exploration for engineering site investigations’, NTIS, U.S. Dept. of Commerce

Soske, J.L., 1959;

‘The blind zone problem in engineering geophysics’, Geophysics, 24, pp 359‐365.

KGS, 2000, Surfseis Users Manual, Kansas Geological Survey.

Park, C.B., Miller, R.D., and Xia, J., 1998;

Ground roll as a tool to image near‐surface anomaly:SEG Expanded Extracts, 68th Annual Meeting, New Orleans, Louisiana, 874‐877.

Park, C.B., Miller, R.D., and Xia, J., 1999;

Multi‐channel analysis of surface waves (MASW): Geophysics, May‐June issue.



6. APPENDIX A: DETAILED METHODOLOGY

6.1 Seismic Refraction Profiling

6.1.1 Principles

The seismic refraction profiling method measures the velocity of refracted seismic waves through the overburden and rock material and allows an assessment of the thickness and quality of the materials present to be made. Stiffer and stronger materials usually have higher seismic velocities while soft, loose or fractured materials have lower velocities. Readings are taken using geophones connected via multi‐core cable to a seismograph.

6.1.2 Data Collection

Four seismic spreads were recorded on the 2nd May 2012 using a Geode high‐resolution 24 channel digital seismograph with geophone spacings of 2m. The source of the seismic waves was a sledgehammer.

6.1.3 Data Processing

The recorded data was interpreted using the ray‐tracing and intercept time methods, to acquire depths to layer boundaries and the P‐wave velocities of these layers, using the FIRSTPIX and GREMIX programs.

GREMIX interprets seismic refraction data as a laterally varying layered earth structure. It incorporates the slope‐intercept method, parts of the Plus‐Minus Method of Hagedoorn (1959), Time‐Delay Method, and features the Generalized Reciprocal Method (GRM) of Palmer (1980). Up to four layers can be mapped, one deduced from direct arrivals and three deduced from refractions. Phantoming of all possible travel time pairs can be carried out by adjusting reciprocal times of off shots.

6.1.4 Relocation

All data were referenced using a Pro‐XS Differential GPS system with c.20mm accuracy.

6.2 MASW

6.2.1 Principles

The Multi‐channel Analysis of Surface Waves (MASW) (Park et al., 1998, 1999) utilizes Surface waves (Rayleigh waves) to determine the elastic properties of the shallow subsurface (<15m). Surface waves carry up to two/thirds of the seismic energy but are usually considered as noise in conventional body wave reflection and refraction seismic surveys.

The penetration depth of surface waves changes with wavelength, i.e. longer wavelengths penetrate deeper. When the elastic properties of near surface materials vary with depth, surface waves then become dispersive, i.e. propagation velocity changes with frequency. The propagation (or phase) velocity is determined by the average elastic



property of the medium within the penetration depth. Therefore the dispersive nature of surface waves may be used to investigate changes in elastic properties of the shallow subsurface.

The MASW method employs the multi‐channel recording and processing techniques (Sheriff and Geldart, 1982) that have similarities to those used in a seismic reflection survey and which allow better waveform analysis and noise elimination. To produce a shear wave velocity (Vs) profile and a stiffness profile of the subsurface using Surface waves the following basic procedure is followed:

(i) A point source (eg. a sledgehammer) is used to generate vertical ground motions,

(ii) The ground motions are measured using low frequency geophones, which are disposed along a straight line directed toward the source,

(iii) the ground motions are recorded using either a conventional seismograph, oscilloscope or spectrum analyzer,

(iv) a dispersion curve is produced from a spectral analysis of the data showing the variation of Surface wave velocity with wavelength,

(v) the dispersion curve in inverted using a modeling and least squares minimization process to produce a subsurface profile of the variation of Surface wave and shear wave velocity with depth,

(vi) a stiffness‐depth profile (shear modulus, G) can be derived from elastic theory.


The recording equipment consisted of a Geode 24 channel digital seismograph, 24 no. 10HZ vertical geophones, hammer energy source with mounted trigger and a 24 take‐out cable, with a 2m geophone spacing. Fieldwork was carried out on the 2nd May 2012. Weather conditions were generally fair to good. Overall data quality was good.

1D MASW Data was acquired during the acquisition of the above seismic refraction spreads S1‐S4, with an additional shot at 1m off each end of each spread.


MASW processing was carried out using the SURFSEIS processing package developed by Kansas Geological Survey (KGS, 2000). SURFSEIS is designed to generate a shear wave (Vs) velocity profile. SURFSEIS data processing involves three steps: (i) Preparation of the acquired multichannel record. This involves converting the data file into the processing format. (ii) Production of a dispersion curve from a spectral analysis of the data showing the variation of Raleigh wave phase velocity with wavelength. Confidence in the dispersion curve can be



estimated through a measure of signal to noise ratio (S/N) which is obtained from a coherency analysis. Noise includes both body waves and higher mode surface waves. To obtain an accurate dispersion curve the spectral content and phase velocity characteristics are examined through an overtone analysis of the data.

(iii) Inversion of the dispersion curve is then carried out to produce a subsurface profile of the variation of shear wave velocity with depth.

The shear wave velocities were then converted into shear modulus values using the formulae: (1)

G = Vs2 *ρ/1000000

Where G = Shear Modulus (MPa)

Vs = Shear Wave Velocity (m/s) ρ = Density (kg/m3)

The Vp velocities were combined with the shear wave velocity data to calculate Poissons ratio, dynamic Bulk modulus and Youngs Modulus for each of the layers outlined by the P‐wave data analysis using the formulae in Davies & Schulteiss, 1980 as follows:

(2) u=(Vp/Vs)²‐2 / 2((Vp/Vs)²‐2) (3) E = 2Vs

2 ρ(1 +u)/1000 where E = Youngs Modulus (GPa) Vs = Shear Wave Velocity (m/s) ρ = Density (kg/m3) u = Poisson’s ratio and (4) B = E/3(1‐2 u) where B = Bulk Modulus (MPa) E = Youngs Modulus (MPa) u = Poisson’s ratio

6.2.4 Relocation

All data were referenced using a Pro‐XR Differential GPS system with c.20mm accuracy.

6.3 Electrical Resistivity Tomography (ERT)

6.3.1 Principles

This surveying technique makes use of the Wenner resistivity array. The 2D‐resistivity profiling method records a large number of resistivity readings in order to map lateral and vertical changes in material types. The 2D‐resistivity profiling method involves the use of 1‐64 electrodes connected to a resistivity meter, using computer software to control the process of data collection and storage.


Profiles R1‐R9 were recorded using a Tigre resistivity meter, imaging software, two 32 takeout multicore cable and up to 64 stainless steel electrodes. Saline solution was used



at the electrode\ground interface in order to gain a good electrical contact required for the technique to work effectively. The recorded data were processed and viewed immediately after the survey. The initial results for Profiles R8‐R9 indicated that these profiles were influences by an underground service.


The field readings were stored in computer files and inverted using the RES2DINV package (Campus Geophysical Instruments, 1997) with up to 5 iterations of the measured data carried out for each profile to obtain a 2D‐Depth model of the resistivities.

The inverted 2D‐Resistivity models and corresponding interpreted geology are displayed on the accompanying drawings. Distance is indicated along the horizontal axis of the profiles. Profiles have been contoured using the same contour intervals and colour codes.

6.3.4 Relocation

All data were referenced using a Pro‐XR Differential GPS system with c.20mm accuracy.

6.4 Ground Conductivity Mapping

6.4.1 Principles

This is an electromagnetic technique used to investigate lateral variations in overburden material and to assist with the indication of the depth to bedrock.

This method operates on the principle of inducing currents in conductive substrata and measuring the resultant secondary electro‐magnetic field. The strength of this secondary EM field is calibrated to give apparent ground conductivity in milliSiemens/metre (mS/m). Readings over material such as organic waste and peat give high conductivity values while readings over dry materials with a low clay mineral content such as gravels, limestone or quartzite give low readings.

The EM31 survey technique determines the apparent conductivity of the ground material from 0‐6m bgl depending on the dipole mode used. Depending on the dipole mode used, the measured conductivity is a function of the different overburden layers and/or rock from 0 to 6m below ground level.


The EM31 equipment used was a GF CMD‐4 conductivity meter equipped with data logger. This instrument features a real time graphic display of the previous 20 measurement points to monitor data quality and results. Conductivity and in‐phase values were recorded one each side of the roadway which surrounds the TMF. Local conditions and variations were recorded.




The conductivity and inphase field readings were downloaded, contoured and plotted using the SURFER 8 program (Golden Software, 2008). Data which was affected by metallic objects was removed. Assignation of material types and possible anomaly sources was carried out, with cross‐reference to other data. The contoured conductivity data are displayed on Drawing 12083_02‐04.

6.4.4 Relocation

All data were referenced using a Garmin handheld system with sub 3m accuracy. All positions are given in Irish National Grid coordinates.



7. APPENDIX B: MASW RESULTS



8. APPENDIX C: DYNAMIC MODULI

S1 Calculation of static and dynamic moduli

Depth Vs Vp density Poissons Shear* Youngs

* Bulk* Youngs** ratio Mod. Mod. Mod. Mod.

(m bgl) m/sec m/sec kg/m^3 MPa GPa GPa MPa Dynamic Dynamic Dynamic Static Gmax Emax

1.473 216 923.1617 2000 0.471 93.32 0.275 1.580 4.74 2.228 216 923.1617 2000 0.471 93.32 0.275 1.580 4.74 2.228 489 923.1617 2000 0.305 477.50 1.247 1.068 57.55 3.171 489 1823.075 2000 0.461 477.50 1.396 6.011 69.33 3.171 619 1823.075 2000 0.435 765.64 2.197 5.626 146.61

4.35 619 1823.075 2000 0.435 765.64 2.197 5.626 146.61 4.35 603 1823.075 2000 0.439 726.06 2.089 5.679 134.90

5.824 603 1823.075 2000 0.439 726.06 2.089 5.679 134.90 5.824 823 3267.585 2700 0.466 1826.73 5.357 26.393 637.86 7.666 823 3267.585 2700 0.466 1826.73 5.357 26.393 637.86 7.666 1032 3267.585 2700 0.445 2872.78 8.300 24.998 1313.93 9.969 1032 3267.585 2700 0.445 2872.78 8.300 24.998 1313.93 9.969 1601 3267.585 2700 0.342 6922.74 18.580 19.598 4965.95

12.461 1601 3267.585 2700 0.342 6922.74 18.580 19.598 4965.95

* from Davies & Schulteiss, 1980. ** converted to static equivalent using empirical correlation from Heerden, 1987.

Soil density taken as 2000kg/m3 Rock density taken as 2700kg/m3







1.319 230 983.0992 2000 0.471 105.81 0.311 1.792 5.83 2.235 230 983.0992 2000 0.471 105.81 0.311 1.792 5.83 2.235 297 983.0992 2000 0.450 175.95 0.510 1.698 13.18

3.38 297 1653.055 2000 0.483 175.95 0.522 5.231 13.68 3.38 492 1653.055 2000 0.451 484.06 1.405 4.820 70.11

4.811 492 1653.055 2000 0.451 484.06 1.405 4.820 70.11 4.811 414 1653.055 2000 0.467 343.07 1.006 5.008 40.41

6.6 414 1653.055 2000 0.467 343.07 1.006 5.008 40.41 6.6 496 1653.055 2000 0.451 491.54 1.426 4.810 71.84

8.836 496 1653.055 2000 0.451 491.54 1.426 4.810 71.84 8.836 745 2873.233 2700 0.464 1498.36 4.387 20.292 458.83

11.631 745 2873.233 2700 0.464 1498.36 4.387 20.292 458.83 11.631 860 2873.233 2700 0.451 1995.81 5.791 19.629 725.47 15.125 860 2873.233 2700 0.451 1995.81 5.791 19.629 725.47 15.125 1267 2873.233 2700 0.379 4334.35 11.957 16.511 2399.51 18.906 1267 2873.233 2700 0.379 4334.35 11.957 16.511 2399.51









1.892 207 366.2775 2000 0.265 85.71 0.217 0.154 3.21 1.892 335 1017.212 2000 0.439 224.15 0.645 1.771 19.41 3.206 335 1017.212 2000 0.439 224.15 0.645 1.771 19.41 3.206 482 1017.212 2000 0.356 463.91 1.258 1.451 58.39 4.848 482 1017.212 2000 0.356 463.91 1.258 1.451 58.39 4.848 331 1017.212 2000 0.441 218.97 0.631 1.777 18.71

6.9 331 1017.212 2000 0.441 218.97 0.631 1.777 18.71 6.9 532 1017.212 2000 0.311 566.78 1.487 1.314 76.94

9.466 532 1017.212 2000 0.311 566.78 1.487 1.314 76.94 9.466 771 3100.353 2700 0.467 1605.27 4.710 23.813 515.87

12.673 771 3100.353 2700 0.467 1605.27 4.710 23.813 515.87 12.673 790 3100.353 2700 0.465 1686.78 4.943 23.704 558.67 16.682 790 3100.353 2700 0.465 1686.78 4.943 23.704 558.67 16.682 866 3100.353 2700 0.458 2024.09 5.901 23.254 748.33









1.269 213 340.1254 2000 0.176 91.05 0.214 0.110 3.14 1.919 213 892.03 2000 0.470 91.05 0.268 1.470 4.54 1.919 409 892.03 2000 0.367 334.66 0.915 1.145 34.54 2.731 409 892.03 2000 0.367 334.66 0.915 1.145 34.54 2.731 678 892.03 2000 3.746 678 892.03 2000 3.746 797.631 892.03 2000 5.015 797.631 892.03 2000 5.015 875.509 3847.05 2700 0.473 2069.59 6.096 37.200 789.50 6.601 875.509 3847.05 2700 0.473 2069.59 6.096 37.200 789.50 6.601 969.485 3847.05 2700 0.466 2537.73 7.441 36.576 1097.14 8.583 969.485 3847.05 2700 0.466 2537.73 7.441 36.576 1097.14 8.583 1540.984 3847.05 2700 0.404 6411.51 18.009 31.411 4716.56

10.729 1540.984 3847.05 2700 0.404 6411.51 18.009 31.411 4716.56





9. APPENDIX D: SEISMIC REFRACTION PLATES



10. APPENDIX E: DRAWINGS

The information derived from the geophysical investigation is presented in the following drawings: 12083_01 Geophysical Location Map 1:2500 @ A3 12083_02 Conductivity Results 1:2500 @ A3 12083_03 Main Conductivity Interpretation 1:2500 @ A3 12083_04 Buildings Conductivity Interpretation 1:1000 @ A3 12083_05 Interpreted Resistivity Sections 1:1000 @ A1

by apex geoservices ltd - environmental protection … · glanbia doc no ie0310818-22-rp-0001 issue...

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