rt o ep - jaws.co.za mwrp/d382-atcoms... · 5.1 laboratory test results ... locations of the pits...

February 2014

ATCOM EAST DRAINS 1 TO 5

Geotechnical Investigation

REPO

RT

Report Number: 13615226 - 12640 - 2 Distribution: 1 x Electronic Copy to Client 1 x Copy to Golder Project File 1 x Copy to Golder Library

Submitted to: Attention: Tebogo Chauke Glencore Coal South Africa (Pty) Ltd iMpunzi Complex

GEOTECHNICAL INVESTIGATION - ATCOM EAST DRAINS

February 2014 Report No. 13615226 - 12640 - 2

Executive Summary

A geotechnical investigation was conducted in order to assess the ground conditions along the stormwater management infrastructure which is set out in Golder report “Preliminary Engineering Design of Stormwater Management Measures for the new Atcom East Pits 1 to 4” under separate cover.

The geotechnical investigation comprised the excavation of 18 test pits using a tractor loader backhoe (TLB) in January and February 2014, as well as preliminary laboratory testing of soil samples collected from the test pit excavations.

The results of the investigation indicated ground conditions typically comprised of a mixture of transported sand silt and clay material, overlying shale and sandstone rock in places. Bands within the transported material were found to be poorly to moderately ferruginised, forming cemented gravel nodules.

TLB refusal occurred in some test pits, and it can be expected that very hard rock sandstone may occur at shallow depth (about 0.5m to 1.5m) along parts of the alignment of drainage structures toward the northeast of Pit 1, east of Pit 3, north of Pit 4. This rock may be excavatable using a large dozer with single ripping tyne, or may in parts require drill and blast. Over the remainder of the alignments, the transported soils are expected to be readily excavatable.

Recommendations are made in the report on excavatability, site preparation, maximum side slopes, and rock fill construction.


February 2014 Report No. 13615226 - 12640 - 2 i

Table of Contents

1.0 INTRODUCTION ........................................................................................................................................................ 1

2.0 OBJECTIVES ............................................................................................................................................................. 2

3.0 REGIONAL GEOLOGY ............................................................................................................................................. 2

3.1 General Locality and Topography ................................................................................................................. 2

3.2 Fieldwork ...................................................................................................................................................... 2

3.2.1 Test Pits .................................................................................................................................................. 2

3.2.2 Laboratory Testing .................................................................................................................................. 3

4.0 RESULTS................................................................................................................................................................... 3

4.1 Ground Conditions ........................................................................................................................................ 3

4.1.1 Pit 1 ......................................................................................................................................................... 3

4.1.2 Pit 2 ......................................................................................................................................................... 3

4.1.3 Pit 3 ......................................................................................................................................................... 4

4.1.4 Pit 4 ......................................................................................................................................................... 4

4.2 Groundwater Level........................................................................................................................................ 4

4.3 Laboratory Testing ........................................................................................................................................ 5

5.0 DISCUSSION ............................................................................................................................................................. 5

5.1 Laboratory Test Results ................................................................................................................................ 5

5.2 Site Preparation ............................................................................................................................................ 5

5.2.1 Rock Fill Berms ....................................................................................................................................... 6

5.2.1.1 Specification ........................................................................................................................................ 6

5.2.1.2 Construction ......................................................................................................................................... 6

5.2.2 Excavatability .......................................................................................................................................... 6

5.2.3 Slope Angles ........................................................................................................................................... 7

5.3 Stability Considerations ................................................................................................................................ 7

6.0 DOCUMENT LIMITATIONS ....................................................................................................................................... 8

TABLES Table 1: Inferred Groundwater Level .......................................................................................................................................... 4

Table 2: Summary of Laboratory Test Results ........................................................................................................................... 5

Table 3: Maximum Recommended Slope Angles for Cut Excavations and Fill Embankments .................................................. 7


February 2014 Report No. 13615226 - 12640 - 2 ii

FIGURES Figure 1: Locality Map of Atcom East Open Pits 1 to 5 .............................................................................................................. 1

Figure 2: Location of Test Pits

APPENDICES APPENDIX A Test Pit Logs and Photographs

APPENDIX B Laboratory Test Certificates

APPENDIX C Document Limitations


February 2014 Report No. 13615226 - 12640 - 2 1

1.0 INTRODUCTION Glencore Coal South Africa (Glencore), a division of Glencore South Africa (Pty) Ltd, intends to submit a Water Use License application (WULA) for five planned Atcom East Open Pits 1 to 5 (Pits 1 to 5). The locations of the pits are indicated in Error! Reference source not found..

Golder Associates (Golder) was commissioned by Glencore to provide engineering input to underpin the WULA. This mainly relates to the conceptualisation and preliminary engineering design of the stormwater water management infrastructure for the sub-catchments affected by the above open pits. These measures have to be aligned to the National Water Act (Act 36 of 1998) (NWA), in particular with GN 704.

Golder has submitted a report entitled “Preliminary Engineering Design of Stormwater Management Measures for the new Atcom East Pits 1 to 5” dated February 2014. The current geotechnical investigation report is intended to serve as an Addendum to the above referenced report.

Figure 1: Locality Map of Atcom East Open Pits 1 to 5

This report presents the results of a preliminary geotechnical investigation for the stormwater management structures recommended in the Golder report entitled “Preliminary Engineering Design of Stormwater Management Measures for the new Atcom East Pits 1 to 5” dated February 2014.



2.0 OBJECTIVES A preliminary geotechnical investigation was conducted with the following objectives;

¡ Determine the geotechnical characteristics along the proposed stormwater alignments; and

¡ Advise/guide the engineering design on the geotechnical site characteristics in terms of the following:

§ Excavation characteristics;

§ Near surface groundwater conditions encountered during the test pitting;

§ Stability of excavation resulting from the construction of the proposed stormwater trenches; and;

§ Any apparent geological features identified during the fieldwork that may potentially affect the design and construction thereof;

3.0 REGIONAL GEOLOGY The 1:250 000 scale geological series 2628 East Rand map published by the Department of Mineral and Energy Affairs dated 1986 indicates that the site is generally located over Karoo Sequence, Ecca Group, Vryheid formation (map symbol Pv) which is described as comprising Sandstone, shale and coal beds. In occasional low lying drainage areas, Quaternary age alluvium materials are present (no map symbol).

3.1 General Locality and Topography The site is located about 20 km due south of Emalahleni (Witbank) and 120 km east of Johannesburg.

The site is topographically relatively flat. There is a gentle northwest/southeast trending ridge line occurring along approximately the centre of the proposed Atcom East Pits 1 and 3, with the surface sloping gradually down to the northeast and southwest either side of the ridge line at an approximate gradient of about 1 to 2 degrees.

The Olifants River occurs toward the north and east of parts of Pits 1, 2, 3 and 4, whilst the Steenskool River occurs toward the west and south of Pits 1, 2 and 3. Outcropping rock is present near portions of the northern/eastern boundaries of Pits 1, 3 and 4.

The area has previously or is currently being mined beyond the footprint of the proposed pits, with disturbed ground and waste stockpiles spread over these areas.

Farming crop lands currently cover much of surface of the proposed pits.

3.2 Fieldwork 3.2.1 Test Pits A total of 18 test pits were excavated over the site using a tractor loader backhoe (TLB) equipped with a 0.7m wide toothed bucket. The test pits were terminated at a depth varying from 0.32m and 3.3m. Premature termination of some test pits at depths of less than about 2.5 m occurred due to refusal of the TLB on rock. The test pit logs and photographs of the excavations are presented in Appendix A.

The quantity and position of test pits were limited by access difficulties caused by dense vegetation, crop fields and soft wet ground conditions.

The positions of the test pits were measured using hand-held GPS by the engineering geologist in the field, to a horizontal accuracy of about 5m. The location of the test pits is presented in Figure 1, together with the position of the proposed pits and the proposed drains and embankments.



3.2.2 Laboratory Testing A program of geotechnical laboratory testing was undertaken on soil samples recovered during the fieldwork phase. The testing comprised the determination of:

¡ Particle size distribution, including hydrometer;

¡ Atterberg limit determination and linear shrinkage;

¡ Emerson Crumb testing (dispersivity); and

¡ Dispersion determination using the Double Hydrometer method.

The laboratory test certificates for all geotechnical tests are presented in Appendix B. A summary of the laboratory test results is provided in Section 4.3.

4.0 RESULTS 4.1 Ground Conditions 4.1.1 Pit 1 Test Pits TP02 to TP05, TP07 to TP12 and TP18 to TP19 were excavated along the proposed Pit 1 perimeter drain.

Outcropping sandstone rock was present over portions of the north-eastern portion of Pit 1, as intersected in TP03, TP08 and TP09, as well as from surface observations. The ground conditions over this area can be summarised as follows:

¡ Silty sand, fine to medium grained, loose to medium dense, topsoil, from the surface to a depth of between 0.15m and 0.9m; overlying

¡ Sandstone, medium hard to very hard (generally very hard).

Over the remainder of the perimeter of Pit 1 where investigated, the ground conditions comprise:

¡ Silty sand (occasionally ferruginised), loose to dense, topsoil, from a depth of 0.0m to 2.7m (generally 0.0m to 1.2m); overlying

¡ Varying proportions of sand, silt and clay, generally medium dense to dense and stiff to very stiff, with occasional ferruginised gravel nodules, transported, from a depth of 0.0m to 2.9m+; with interbedded:

¡ Sandy gravel/sandy clayey gravel, generally medium dense to dense, ferruginised gravel nodules, transported; from a depth of 0.6m to 1.7m; overlying

¡ Shale (TP05), very soft to soft rock strength, or Silty clay comprising residual shale (TP11 and TP19), stiff to very stiff, from a depth of 1.4m to 2.9m+.

4.1.2 Pit 2 The ground conditions at Pit 2 were investigated by means of test pits TP12, TP13, TP15 and TP18, and can be summarised as follows:

¡ Fill comprised of sandy gravel and clayey sand, dense was intersected in TP15 from a depth of 0.0m to 1.3m; overlying

¡ Silty sand/Clayey silty sand/Gravelly silty sand, with occasional ferruginised nodules, generally loose to dense, transported, from a depth of 0.0m to 3.0m+; overlying

¡ Sand with silt, transported, from a depth of 2.5m to 2.9m+ in TP15; and

¡ Sandy gravel, transported, from a depth of 3.0m to 3.1m+ in TP12; and



¡ Gravel possibly comprising residual sandstone 2.6m to 2.7m+ in TP13.

4.1.3 Pit 3 The ground conditions at Pit 3 were investigated by means of test pits TP13, TP25, TP27 and TP28, and can be summarised as follows:

¡ Silty sand/ Gravelly silty sand, with occasional ferruginised nodules, very loose to dense, transported, from a depth of 0.0m to 2.6m+; overlying

¡ Sand/Gravel, with silt, fine to medium grained, transported, from a depth of 0m to 0.9m+; and

¡ Clayey sand/Clayey sandy gravel, occasionally ferruginised nodules, transported, from a depth of 0.5m to 2.4m; and

¡ Sandy Clay, very stiff to hard, transported, from 1.5m to 2.6m+; overlying

¡ Sandstone/ Gravel comprising residual sandstone from a depth of 1.0m to 2.7m+. The sandstone intersected in TP28 was medium to hard rock strength and the TLB encountered excavation refusal.

4.1.4 Pit 4 The ground conditions at Pit 3 were investigated by means of test pits TP10 to TP12 and TP22, and can be summarised as follows:

¡ Sand /Silty sand, medium dense, topsoil, from a depth of 0.0m to 3.0m+; overlying

¡ Gravelly sand/Sandy gravel, medium grained, ferruginised gravel nodules, dense to very dense, transported, from a depth of 0.6m to 3.1m+, with interbedded

¡ Clayey sandy gravel, medium grained ferruginised gravel nodules, very dense, transported, from a depth of 2.9m to 3.3m+ in TP22; and

¡ Sandy Clay, stiff to very stiff, from 0.3m to 2.3m in TP10 soft to firm, becoming firm then stiff to very stiff from 2.0m, transported; overlying

¡ Silty clay, very stiff, residual shale, from 2.2m to 2.5m+ in TP11; overlying

¡ Shale, very soft to soft rock strength, from 1.4m to 2.6m+ in TP10 and TP11.

4.2 Groundwater Level The groundwater level, inferred based on the depth below which moist to wet ground conditions were intersected, is presented in Table 1 below, together with the depth at which groundwater seepage into the test pit was observed. The groundwater is likely to be perched water resulting from the recent rains in the area.

Table 1: Inferred Groundwater Level

Test Pit ID

Depth of at least moist to wet soil (m)

Depth of Groundwater Seepage (m)

TP04 1.8 2.4 TP10 0.0 (surface) 1.4 TP15 2.5 - TP18 0.0 (surface) 0.2 TP19 0.9 1.5

Groundwater was generally encountered in test pits located toward the south of the Pit 1, where topographic low areas produced poor drainage and wet surface conditions were observed after recent rains.



4.3 Laboratory Testing A summary of the geotechnical laboratory testing is provided in Table 2 below: Table 2: Summary of Laboratory Test Results

Test

Pit

ID

Dep

th (m

)

Uni

fied

Cla

ssifi

catio

n

Liqu

id L

imit

Line

ar S

hrin

kage

Plas

ticity

Inde

x*

Particle Size Distribution (% Comprising)

Emer

son

Cru

mb

Dis

pers

ion

(%)

Gra

vel

Sand

Silt

Cla

y

TP07 0.7-0.8 SC 20 4 9 3 60 19 18 Class 2, subclass 3 0.0

TP10 0.1-0.2 SM NO 1 NO 0 75 22 3 Class 8 -

TP11 2.5-2.6 CL 42 9 22 0 48 18 34 Class 2, subclass 3 -

TP15 1.7-1.9 SC 23 4 11 2 57 24 17 Class 2, subclass 3 -

TP19 0.2-0.3 CL 23 5 12 3 50 35 13 - -

TP19 1.9-2.0 CL 33 6 14 2 32 34 32 - -

TP27 1.3-1.4 SM&SC 18 2 6 7 62 16 14 - - NO: not-obtainable; *on fines material

5.0 DISCUSSION 5.1 Laboratory Test Results The laboratory test results indicate a generally high fines component (comprising silt and clay). The fines component is generally of low plasticity, due to the high silt content. The material displays a generally high linear shrinkage value, but low potential expansiveness.

Dispersivity impacts on the potential erodability of the exposed material in the proposed drains. The dispersion testing results indicate that the material is generally non-dispersive to slightly dispersive in nature.

Layers with ferruginised gravel nodules were frequently observed in test pits. Laboratory testing of this material indicates the gravel nodules are typically not of sufficient strength/ cementation to resist crushing during sample handling, transportation and laboratory sample preparation. The ferruginised nodules appear to typically crush to a sand or silt, with a resultant low percentage of gravel in the final results.

5.2 Site Preparation The footprint below the drains, basins and embankments should be prepared as follows:

¡ Strip topsoil, organic and unsuitable materials to a depth of about 200mm. All topsoil should be stockpiled for use in rehabilitation works.

¡ Where large water flows are expected, construct diversion drainage up slope of the work area to divert surface water flows away from the construction site.

¡ Excavate to design subgrade level.

¡ Carry out proof compaction of the exposed subgrade surface using a vibratory roller of at least 10 tonne static mass in order to achieve a MOD AASHTO dry density ratio of not less than 92% to a depth of about 0.7m. No such compaction is required where rock is exposed.



¡ Remove any weak areas that develop in response to compaction and replace with approved gravel or rock fill. Local zones of low permeability (and more-cohesive) material such as through existing natural drainage channels may occur at design subgrade level. These should be over-excavated to a minimum of 0.5m depth and up to a maximum depth of 1m, and replaced with approved and compacted fill material.

5.2.1 Rock Fill Berms 5.2.1.1 Specification The material used for rock berm construction is likely to comprise sandstone rock derived from the mining activities. The use of shale (or carbonaceous shale) material, or flat/platy particles or highly weathered sedimentary rocks is generally not advised due slaking of the shale and the presence of plastic fines. It is recommended that the materials proposed for use should be evaluated by a geotechnical engineer.

The Rock Fill should be:

i) Clean, cohesionless and free of all organic and deleterious material.

ii) Contains less than 10% by weight of soil fractions finer than 0.075mm (i.e. fines).

iii) Particles shall have a maximum particle size of 300mm.

iv) Particles shall be at least hard rock strength, be durable and not break down excessively under handling, compaction or after weathering.

5.2.1.2 Construction The following construction procedure should be used for construction of Rock Fill berms:

¡ Place and compact approved Rock Fill in loose layers of no greater than 300mm thickness.

¡ Shall be sluiced in with water, and each layer compacted with at least 8 passes of a 10 tonne (minimum static mass) smooth drum vibratory roller. Where a smaller compactor is preferred due to access or berm width considerations, the compaction plant and method specification should be chosen so at to provide an equivalent level of compaction.

5.2.2 Excavatability A Stilling Basin and Waste Rock Berm is proposed around Pit 3, as well as the northern boundary of Pit 4. Sandstone can be anticipated at shallow depths near to large portions of the Olifants River, located near the eastern boundary of Pit 3 and the northern boundary of Pit 4. This is likely to impact of the drainage abilities and any excavations in the area.

Generally, the soil occurred to the base of the test pit, which was terminated at a depth of upto 3.3m. These materials are expected to be excavatable using standard earth moving equipment such as an excavator or dozer.

Highly weathered sandstone and shale was intersected TP03, TP10, TP11, TP13 and TP19 from a depth of 0.9m to 2.9m+. We expect that this material will be excavatable using standard earth moving equipment such as an excavator or dozer. In places, ripping tynes may be needed for effective excavation.

The TLB reached refusal on hard to very hard rock sandstone during excavation of the test pits at a depth of 0.17 m to 1.8m in TP03, TP08, TP09 and TP28. It is possible that the rock is partially cemented in the upper crust of the rock layer, and less cemented at deeper depths. This would lead to an over-estimation of the rock strength as the TLB may have refused in this harder rock upper crust layer. Due to premature refusal, and in the absence of better information, the more conservative assessment is made that the rock is of similar strength as the strength encountered at refusal depth.

Based on the preceding comment, it can be expected that hard to very hard rock sandstone may occur at shallow depths (about 0.5m to 1.5m) along parts of the alignment of drainage structures toward the northeast



of Pit 1, east of Pit 3, north of Pit 4. This material may be excavatable with difficulty using a large dozer with single ripping tyne. It is anticipated that in wide open excavations, the very hard rock sandstone will be more-readily excavated once the open face has been created, and the rock mass attacked from its weakest exposures. In parts however, drill and blast may be required.

5.2.3 Slope Angles Recommended average slopes for cut excavations or for fill embankments are provided in Table 3 below, which assumes that groundwater is located below the base of the excavation/embankment.

Large rainfall events are known to have occurred in the area which may affect stability of excavations or site trafficability, and cause notable softening of the finer surface soils.

Table 3: Maximum Recommended Side Slope Angles for Cut Excavations and Fill Embankments Subgrade Material

Type Maximum Side

Slope Angle

Grassed or Unlined Excavations/Embankments

Sand, clay or silt 1V:3H Ferruginised Gravel 1V:2.5H Rock 1V:1H

Waste Rock Lined Sand, clay or silt 1V:2H Ferruginised Gravel 1V:1.5H Rock 1V:1.5H

Concrete Lined Sand, clay or silt 1V:2.0H Ferruginised Gravel 1V:1.5H H: Horizontal; V: Vertical.

5.3 Stability Considerations Consideration should be made of the impact of the drain on the stability of the adjacent pit, and visa versa. Stability will be affected by the geometry, ground conditions, hydraulics and distance between the drains and pits. This was not included within the scope of the current study.



6.0 DOCUMENT LIMITATIONS Your attention is drawn to Appendix C: “Document Limitations”. The statements presented in this document are intended to advise you of what your realistic expectations of this report should be, and to present you with recommendations on how to minimise the risks associated with the groundworks for this project. The document is not intended to reduce the level of responsibility accepted by Golder Associates, but rather to ensure that all parties who may rely on this report are aware of the responsibilities each assumes in so doing.

GOLDER ASSOCIATES AFRICA (PTY) LTD.

Simon Owens-Collins Senior Engineering Geologist, Associate

SOC/BT/soc

Reg. No. 2002/007104/07 Directors: SAP Brown, L Greyling, RGM Heath Golder, Golder Associates and the GA globe design are trademarks of Golder Associates Corporation.

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APPENDIX A Test Pit Logs and Photographs

Moist, reddish brown, medium dense to dense, silty sand fine to medium grained.

TRANSPORTED.

Moist, orange brown, medium dense to dense, silty gravelly sand fine to mediumgrained, with medium grained ferruginised nodules.

TRANSPORTED.

Target depth reached.End of log

0.00

2.20

2.70

PROJECT NO: 13615226

TEST PIT PROFILE

FILE REF:

CONTRACTOR: DATE EXCAVATED:

13615226_AKOM EAST.GPJPIT LxB:

MACHINE: DATE PROFILED:

CLIENT:PROJECT:

Glencore Coal South Africa (Pty) LtdAtcom East Drains 1 to 5Atcom East, Mpumalanga, South Africa

PROFILED BY:30/01/2014

30/01/2014

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HOLE No:X COORD: 7109337

TP02

ELEVATION:UTM 35J

Y COORD: 727822DATUM:

Golder Associates Africa (Pty) Ltd244 Surrey AvenueFerndale, Randburg, 2125Telephone: +27-11-789-3742Fax: +27-11-886-0248

0.5

1.0

1.5

2.0

2.5

3.0

3.5

APPENDIX A Test Pit Photos

February 2014 Reference No. 13615226 1/18

Test Pit TP02

Dry, brown, loose, sand with silt and trace rootlets.

TOPSOIL.

Dry to moist, orange brown, loose, silty sand.

TRANSPORTED.

Moist, mottled pale white and orange.

Mottled pale white and orange, highly weathered, medium to coarse grained, soft tomedium hard

SANDSTONE.

Reddish brown, medium weathered, fine to medium grained, medium hard rock,ferruginised

SANDSTONE.

Practical refusal on medium strength sandstoneEnd of log

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TP03

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP03

Dry, brown, medium dense to dense, sand fine to medium grained trace rootlets.

TOPSOIL.

Dry to moist, reddish brown, medium dense to dense, silty sand fine to mediumgrained.

TOPSOIL.

Moist then moist to wet from 1.8m, reddish brown, stiff, silty gravelly clay low plasticity.

SLIGHTLY FERRUGINISED TRANSPORTED.

Moist to wet then wet from 2.4m, reddish brown, stiff, sandy silt with clay.

SLIGHTLY FERRUGINISED.

Target depth reachedEnd of log

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TP04

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP04

Dry to moist, brown, medium dense to dense, sand fine to medium grained, with siltand clay trace rootlets.

TOPSOIL.

Moist, pale grey, stiff, silty clay with sand, low plasticity with a ferruginised layer from0.5m to 0.6m.

TRANSPORTED.

Moist, pale grey, very stiff, silty clay with sand, low plasticity.

TRANSPORTED.

Moist, pale orange mottled pale grey, very stiff, sandy clay low plasticity slightlyferruginised.

TRANSPORTED.


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TP05

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP05

Dry, brown, medium dense, sand fine to medium grained trace rootlets.

TOPSOIL.

Dry to moist, orange brown, medium dense to dense, clayey silty sand fine to mediumgrained, low plasticity fines.

TRANSPORTED.

Dry to moist, orange brown, dense to very dense, clayey gravel medium to coarsegrained, with ferruginised gravel nodules.

TRANSPORTED.

Moist, pale grey mottled reddish brown, very stiff, gravelly clay with sand, low plasticity,slightly to moderately ferruginised nodules.

TRANSPORTED.


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TP07

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP07

Dry to moist, dark brown, medium dense, silty sand fine to medium grained tracerootlets.

TOPSOIL.

Brown, medium weathered, medium to coarse grained, very hard rock

SANDSTONE.

Total refusal on sandstoneEnd of log

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TP08

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP08

Dry, brown, loose, sand fine to medium grained.

TOPSOIL.

Orange brown ferruginised, medium weathered, very hard rock, ferruginised

SANDSTONE.

Total refusalEnd of log

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1:NOTES: Significant outcropping ferricrete/ferruginised sandstone on western flank of river

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TP09

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP09

Moist to wet, dark brown, loose, silty sand fine to medium grained, non-plastic fineswith organic fines, trace rootlets.

TOPSOIL.

Moist to wet, brown, soft, sandy clay low plasticity.

TRANSPORTED.

Wet, pale grey, very soft to soft, sandy clay or clay sand, low plasticity.

TRANSPORTED.

Wet, pale grey mottled pale orange, soft to firm becoming firm from 1.6m, thenbecoming stiff to very stiff from 2.0m, sandy clay low plasticity.

TRANSPORTED.

Pale orange mottled pale grey, highly weathered, fine grained, very soft rock, to softrock

SHALE.


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TP10

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP10

Dry, brown, medium dense, silty sand fine to medium grained.

TOPSOIL.

Dry to moist, reddish brown, medium dense to dense, clayey silty sand fine to mediumgrained.

TRANSPORTED.

Moist, reddish brown, very dense, sandy gravel medium grained.

TRANSPORTED.

Pale grey mottled pale orange, highly weathered, fine grained, very soft rock, to softrock, very slightly iron indurated

SHALE.

Moist, pale greyish orange, very stiff, sandy silty clay low plasticity, with bands of verysoft shale.

RESIDUAL SHALE.


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CLIENT:PROJECT:



16/01/2014

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CHECKED BY:

Lege

nd

Scal

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DescriptionD

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NOTES:

Page 1 of 1


TP11

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP11

Dry, brown, loose, silty sand fine to medium grained, trace clay trace rootlets.

TOPSOIL.

Dry, brown, medium dense, silty sand fine to medium grained, with clay.

TRANSPORTED.

Dry to moist, red, medium dense to dense, silty sand fine to medium grained, with clay.

TRANSPORTED.

Dry to moist, dark reddish brown, very dense, sandy gravel fine to medium grained,ferruginised.

TRANSPORTED.


0.00

0.30

0.50

3.003.10


TEST PIT PROFILE

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DescriptionD

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NOTES:

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TP12

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP12

Dry, reddish brown, medium dense, silty sand fine to medium grained, with tracerootlets and gravel.

TOPSOIL.

Dry, medium dense, silty sand fine to medium grained.

TRANSPORTED.

Dry to moist, red, medium dense to dense, silty sand fine to coarse grained, with lowplasticity clay.

TRANSPORTED.

Dry to moist, pale brown, very dense, gravel fine grained, angular decomposedsandstone, possible very soft rock sandstone.

DECOMPOSED SANDSTONE.


0.00

0.30

0.60

2.602.70


TEST PIT PROFILE

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TP13

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP13

Dry to moist, dark brown, dense, sandy gravel fine to coarse.

FILL.

Dry to moist, pale orange, dense, clayey sand fine to coarse, with gravel.

FILL.

Dry to moist, reddish brown, medium dense to dense, clayey silty sand fine to mediumgrained, low plasticity fines.

TRANSPORTED.

Moist to wet, pale brown, medium dense, sand fine to medium grained, with silt.

TRANSPORTED.


0.00

0.70

1.30

2.50

2.90


TEST PIT PROFILE

FILE REF:




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30/01/2014

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DescriptionD

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1:NOTES: located in a poorly drained low point adjacent the railway line

Page 1 of 1


TP15

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP15

Moist to wet, brown, loose, silty sand fine grained.

TOPSOIL.

Wet, brown, very loose, silty sand fine grained.

TOPSOIL.

Test pit terminated due to sidewall collape in saturated sandEnd of log

0.00

0.40

1.80


TEST PIT PROFILE

FILE REF:




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1:NOTES:Groundwater seepage from 0.2m2:Test located in a poorly drained lowpoint adjacent railway line.

Page 1 of 1


TP18

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP18

Moist, brown, medium dense, clayey silty sand fine to medium grained, low plasticityfines.

TRANSPORTED.

Moist, reddish brown, medium dense, sand fine to medium grained, with silt.

TRANSPORTED.

Moist to wet, mottled pale grey and orange brown, dense becoming very dense from1.2m, sandy clayey gravel medium to coarse grained, with ferruginised gravel nodules.

TRANSPORTED.

Wet, mottled pale orange brown and pale grey, very stiff to hard, sandy clayey silt lowplasticity, very slightly ferruginised.

RESIDUAL SHALE.


0.00

0.70

0.90

1.70

2.90


TEST PIT PROFILE

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DescriptionD

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1:NOTES: Groundwater seepage at 1.5m

Page 1 of 1


TP19

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP19

Dry to moist, reddish brown, medium dense, sand fine to medium grained, with silt.

TRANSPORTED.

Dry to moist, reddish brown, medium dense to dense, sand fine to medium grained,with silt.

TRANSPORTED.

Dry, orange brown, dense, gravelly sand fine to medium grained, or sandy gravel,ferruginised nodules.

TRANSPORTED.

Dry, pale orange brown, very dense, clayey sandy gravel fine to coarse grained gravellithic clasts, weakly to moderately ferruginised.

TRANSPORTED.


0.00

1.80

2.30

2.90

3.30


TEST PIT PROFILE

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DescriptionD

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1:NOTES: About 300m from river

Page 1 of 1


TP22

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP22

Dry to moist, brown, medium dense to dense, sand fine to medium grained, with silt.

TOPSOIL.

Dry to moist, reddish brown, medium dense to dense, silty sand fine to mediumgrained.

TRANSPORTED.

Dry to moist, mottled pale grey and reddish brown, medium dense, clayey sand fine tomedium grained, very weakly ferruginised.

TRANSPORTED.

Dry to moist, mottled pale grey and reddish brown, very dense, clayey sandy gravel fineto coarse grained.

TRANSPORTED.

Moist, mottled pale grey and reddish brown, very dense and hard, sandy clay possiblyclayey fine to medium sand (engineering behaviour as a high plasticity clay), veryweakly ferruginised.

TRANSPORTED.


0.00

0.40

1.70

1.90

2.40

2.60


TEST PIT PROFILE

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DescriptionD

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NOTES:

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TP25

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP25

Dry, brown, very loose to loose, sand fine grained trace rootlets.

TRANSPORTED.

Dry, pale brown, very loose to loose, sand fine grained.

TRANSPORTED.

Moist, pale grey mottled orange brown, dense, clayey silty sand low plasticity fines, withtrace gravel, very weakly ferruginised.

TRANSPORTED.

Moist, pale grey mottled orange brown, stiff to very stiff, clay low plasticity, with sand,very weakly ferruginised.

TRANSPORTED.


0.00

0.30

0.60

1.50

2.80


TEST PIT PROFILE

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CLIENT:PROJECT:



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1:NOTES: Outcropping sandstone in creek about 200m north

Page 1 of 1


TP27

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP27

Dark brown, loose to medium dense, sand medium grained, with silt trace rootlets.

TOPSOIL.

Brown, medium dense, sand medium grained, with silt.

TRANSPORTED.

Pale grey and orange, medium dense, clayey sand fine to coarse grained, withoccasional subrounded tabular sandstone boulders up to 0.8m x 0.2m.

TRANSPORTED.

Pale grey, dense, gravel fine grained, with coarse grained sand.

TRANSPORTED.

Orange, dense to very dense, silty sand fine to coarse grained, very weaklyferruginised.

TRANSPORTED.

Pale orange brown, highly weathered, fine to coarse grained, medium hard rock

SANDSTONE.

TLB refused on sandstoneEnd of log

0.00

0.400.50

0.70

0.901.00


TEST PIT PROFILE

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CHECKED BY:

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DescriptionD

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NOTES:

Page 1 of 1


TP28

ELEVATION:UTM 35J



0.5

1.0

1.5

2.0

2.5

3.0

3.5



Test Pit TP28



APPENDIX B Laboratory Test Certificates

Sample No.Soillab sample no. S14-0117-1 S14-0117-2Depth (m) 0.1-0.2 2.5-2.6Position TP 10 TP 11Material DARK GREY LIGHT OLIVEDescription FERRICRETE

SILTY CLAYEYSAND SAND

Moisture (%)Dispersion (%)

SCREEN ANALYSIS ( % PASSING) (TMH 1 A1(a) & A5)

63.0 mm 100 10053.0 mm 100 10037.5 mm 100 10026.5 mm 100 10019.0 mm 100 10013.2 mm 100 1004.75 mm 100 1002.00 mm 100 100

0.425 mm 82 880.075 mm 29 56

HYDROMETER ANALYSIS ( % PASSING) (TMH 1 A6)

0.040 mm 20 460.027 mm 15 420.013 mm 11 390.005 mm 8 350.002 mm 3 34

% Clay 3 34% Silt 22 18% Sand 75 48% Gravel 0 0

ATTERBERG LIMITS (TMH 1 A2 - A4)

Liquid Limit 42Plasticity Index SP 22Linear Shrinkage (%) 1.0 9.0Grading Modulus 0.90 0.55Uniformity coefficient 24 - Coefficient of curvature 3.4 - Classification A-2-5 (0) A-7-6 (9)Unified Classification SM CL

(PTY) LTD 230 Albertus Street P O Box 72928La Montagne 0184 Lynnwood Ridge 0040

Reg No / / Tel (012) 481-3999 Fax (012) 481-3812SOILLAB

PARTICLE SIZE ANALYSIS

Chart Reference

PROJECT : ATCOM EAST PITS 1 TO 5JOB No. : S14-0117DATE : 31/01/2014

0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80

PI o

f who

le s

ampl

e

Clay fraction of whole sample

POTENTIAL EXPANSIVENESS

0

20

40

60

80

100

Cum

ulat

ive

% p

assi

ng

0.002 0.01 0.02 0.06 0.1 0.2 0.5 1.0 2.0 5.0 10 50 100

VERY HIGH HIGH

MEDIUM

LOW

CLAY GRAVEL SILT SAND

0 0.2 0.4 0.6 0.8 1 1.2 0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Plas

ticity

Inde

x

Liquid Limit

PLASTICITY CHART

HIDROMETER/0117-01

Sample No.Soillab sample no. S14-0117-4 S14-0117-5Depth (m) 1.3-1.4 0.2-0.3Position TP 27 TP 19Material LIGHT OLIVE DARK BROWNDescription FERRICRETE FERRICRETE

SILTY SILTYSAND SAND

Moisture (%)Dispersion (%)



0.425 mm 89 920.075 mm 35 56


0.040 mm 25 370.027 mm 21 310.013 mm 18 220.005 mm 16 170.002 mm 14 13



Liquid Limit 18 23Plasticity Index 6 12Linear Shrinkage (%) 2.0 5.0Grading Modulus 0.83 0.55Uniformity coefficient - - Coefficient of curvature - - Classification A-2-4 (0) A-6 (3)Unified Classification SM & SC CL




Chart Reference


0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80

PI o

f who

le s

ampl

e



0

20

40

60

80

100

Cum

ulat

ive

% p

assi

ng

0.002 0.01 0.02 0.06 0.1 0.2 0.5 1.0 2.0 5.0 10 50 100

VERY HIGH HIGH

MEDIUM

LOW


0 0.2 0.4 0.6 0.8 1 1.2 0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Plas

ticity

Inde

x

Liquid Limit

PLASTICITY CHART

HIDROMETER/0117-02

Sample No.Soillab sample no. S14-0117-6 S14-0117-7Depth (m) 1.9-2.0 1.7-1.9Position TP 19 TP 15Material LIGHT Y ORANGE PALE REDDescription FERRICRETE+SHALE FERRICRETE

CLAYEY SILTY

SILT SANDMoisture (%)Dispersion (%)



0.425 mm 94 870.075 mm 73 47


0.040 mm 56 330.027 mm 51 300.013 mm 43 240.005 mm 38 190.002 mm 32 17



Liquid Limit 33 23Plasticity Index 14 11Linear Shrinkage (%) 6.0 4.0Grading Modulus 0.35 0.67Uniformity coefficient - - Coefficient of curvature - - Classification A-6 (9) A-6 (2)Unified Classification CL SC


Reg No / / Tel (012) 481-3999 Fax (012) 481-3812

Chart Reference


SOILLAB


0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80

PI o

f who

le s

ampl

e



0

20

40

60

80

100

Cum

ulat

ive

% p

assi

ng

0.002 0.01 0.02 0.06 0.1 0.2 0.5 1.0 2.0 5.0 10 50 100

VERY HIGH HIGH

MEDIUM

LOW


0 0.2 0.4 0.6 0.8 1 1.2 0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Plas

ticity

Inde

x

Liquid Limit

PLASTICITY CHART

HIDROMETER/0117-03

Sample No.Soillab sample no. S14-0117-3Depth (m) 0.7-0.8Position TP 7Material DARK Y ORANGEDescription FERRICRETE

SILTYSAND

Moisture (%)Dispersion (%) 0.0


63.0 mm 10053.0 mm 10037.5 mm 10026.5 mm 10019.0 mm 10013.2 mm 1004.75 mm 992.00 mm 97

0.425 mm 910.075 mm 41


0.040 mm 330.027 mm 270.013 mm 240.005 mm 200.002 mm 18

% Clay 18% Silt 19% Sand 60% Gravel 3


Liquid Limit 20Plasticity Index 9Linear Shrinkage (%) 4.0Grading Modulus 0.71Uniformity coefficient - Coefficient of curvature - Classification A-4 (0)Unified Classification SC




Chart Reference


0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80

PI o

f who

le s

ampl

e



0

20

40

60

80

100

Cum

ulat

ive

% p

assi

ng

0.002 0.01 0.02 0.06 0.1 0.2 0.5 1.0 2.0 5.0 10 50 100

VERY HIGH HIGH

MEDIUM

LOW


0 0.2 0.4 0.6 0.8 1 1.2 0 0.2 0.4 0.6 0.8 1 1.2

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Plas

ticity

Inde

x

Liquid Limit

PLASTICITY CHART

HIDROMETER/0117-04

CLI

EN

T

: G

OLD

ER A

SS

OC

IATE

S

PR

OJE

CT

: A

TCO

M E

AST

PIT

S 1

TO 5

P

RO

JEC

T N

O.

: S

14-0

117

DA

TE

:

2014

-02-

03

D

ATE

TE

STE

D:

:

N

ATU

RA

L M

OIS

TUR

E:

: Y

ES

/ N

O /

DIS

TILL

ED

WAT

ER

AD

DE

D

MO

ISTU

RE

CO

NTE

NT

: %

TE

ST W

ATE

R

EC

: 4

.22

SIE

MEN

S /

cm

Ph

: 6.8

1

WAT

ER T

EM

PER

ATU

RE

IN

ITIA

L

: 2

2 °C

Soi

llab

No

Sam

ple

No

Dep

th

(m)

Dis

h N

o 2

HO

UR

S

20 H

OU

RS

G

rade

Te

mp.

G

rade

Te

mp

S14

-011

7-01

TP

10

0.1-

0.2

1 N

o S

laki

ng. N

o S

wel

ling

(Cla

ss 8

) N

o S

laki

ng. N

o S

wel

ling

(Cla

ss 8

)

S14

-011

7-02

TP

11

2.5-

2.6

2 S

laki

ng. S

ome

disp

ersi

on (C

lass

2) *

S

laki

ng. S

ome

disp

ersi

on (C

lass

2)

S14

-011

7-03

TP

7 0.

7-0.

8 3

Sla

king

. Som

e di

sper

sion

(Cla

ss 2

) *

Sla

king

. Som

e di

sper

sion

(Cla

ss 2

)

S14

-011

7-07

TP

15

1.7-

1.9

4 S

laki

ng. S

ome

disp

ersi

on (C

lass

2) *

S

laki

ng. S

ome

disp

ersi

on (C

lass

2)

Not

e *

Sub

clas

s 3:

Agg

rega

te b

reak

s do

wn

com

plet

ely

into

san

d gr

ains

. S

oil S

urve

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tand

ard

Test

Met

hod.



APPENDIX C Document Limitations

DOCUMENT LIMITATIONS

GAA Form 201 Version 0

May 2010 1/1

DOCUMENT LIMITATIONThis Document has been provided by Golder Associates Africa Pty Ltd (“Golder”) subject to the followinglimitations:

i) This Document has been prepared for the particular purpose outlined in Golder’s proposal and noresponsibility is accepted for the use of this Document, in whole or in part, in other contexts or for anyother purpose.

ii) The scope and the period of Golder’s Services are as described in Golder’s proposal, and are subject torestrictions and limitations. Golder did not perform a complete assessment of all possible conditions orcircumstances that may exist at the site referenced in the Document. If a service is not expresslyindicated, do not assume it has been provided. If a matter is not addressed, do not assume that anydetermination has been made by Golder in regards to it.

iii) Conditions may exist which were undetectable given the limited nature of the enquiry Golder wasretained to undertake with respect to the site. Variations in conditions may occur between investigatorylocations, and there may be special conditions pertaining to the site which have not been revealed bythe investigation and which have not therefore been taken into account in the Document. Accordingly,additional studies and actions may be required.

iv) In addition, it is recognised that the passage of time affects the information and assessment provided inthis Document. Golder’s opinions are based upon information that existed at the time of the productionof the Document. It is understood that the Services provided allowed Golder to form no more than anopinion of the actual conditions of the site at the time the site was visited and cannot be used to assessthe effect of any subsequent changes in the quality of the site, or its surroundings, or any laws orregulations.

v) Any assessments made in this Document are based on the conditions indicated from published sourcesand the investigation described. No warranty is included, either express or implied, that the actualconditions will conform exactly to the assessments contained in this Document.

vi) Where data supplied by the client or other external sources, including previous site investigation data,have been used, it has been assumed that the information is correct unless otherwise stated. Noresponsibility is accepted by Golder for incomplete or inaccurate data supplied by others.

vii) The Client acknowledges that Golder may have retained sub-consultants affiliated with Golder toprovide Services for the benefit of Golder. Golder will be fully responsible to the Client for the Servicesand work done by all of its sub-consultants and subcontractors. The Client agrees that it will only assertclaims against and seek to recover losses, damages or other liabilities from Golder and not Golder’saffiliated companies. To the maximum extent allowed by law, the Client acknowledges and agrees it willnot have any legal recourse, and waives any expense, loss, claim, demand, or cause of action, againstGolder’s affiliated companies, and their employees, officers and directors.

viii) This Document is provided for sole use by the Client and is confidential to it and its professionaladvisers. No responsibility whatsoever for the contents of this Document will be accepted to any personother than the Client. Any use which a third party makes of this Document, or any reliance on ordecisions to be made based on it, is the responsibility of such third parties. Golder accepts noresponsibility for damages, if any, suffered by any third party as a result of decisions made or actionsbased on this Document.

GOLDER ASSOCIATES AFRICA (PTY) LTD

g:\new structure\99605 - risk division\gaims\forms\gaa form 201_rev 1.docx

Golder Associates Africa (Pty) Ltd. PO Box 6001 Halfway House, 1685 Building 1 , Golder House, Magwa Crescent West Maxwell Office Park, Waterfall City Cnr Allandale Road and Maxwell Drive Midrand South Africa T: [+27] (11) 254 4800

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