Geotechnical Investigation for the Rehabilitation of Albert's Farm

Geotechnical investigation for the rehabilitation of Albert’s Farm Dam – Braamfontein West Water Management Unit Reference: 504630-G3-00 Report No: 12239 Revision: 00 26 July 2019

Executive Summary

The Johannesburg Roads Agency (JRA) was appointed by the Environment and Infrastructure Services Department (EISD), the implementing agent for the Water and Biodiversity Project, for rehabilitation of a number of dams within the Braamfontein West Water Management Unit in the City of Johannesburg. As part of this appointment JRA appointed Aurecon for the design of the remedial works. Aurecon Ground Engineering conducted geotechnical investigations for these dams; the findings of the investigations into Albert’s Farm Dam, are presented in this report.

The field investigation was conducted on the 29th of May 2019 and comprised excavation of four test pits across the site. Four other planned test pits were not excavated due to their location in a conservation area.

Representative samples were taken from selected horizons and submitted to SANAS accredited laboratory, Civilab, to determine the material’s geotechnical properties. The results are summarised and discussed in the report and full laboratory test result sheets attached to Appendix D.

A visual assessment of the surface conditions across the site was also conducted prior to and during the test pitting noting features that might have an impact on the proposed design and rehabilitation.

The objectives of the geotechnical investigation were: • To characterise the materials in the embankment and immediate environs, with a view to assessing their use in the embankment, • To provide such inputs to the dam design team, • To appraise geotechnical factors that might influence the dam condition, as well as re-design and construction, and • To provide generic geotechnical related considerations and recommendations.

According to the geological map of the area (West Rand 2626, 1:250 000 geological map), the site is underlain by quartzite and shale of the Orange Grove Formation of the West Rand Group, Witwatersrand Supergroup which is intruded by younger diabase rocks. Outcrops of quartzite occur some 100m northwest of the dam. No major faults occur in the general area.

Assessment of the embankment showed that previously the dam wall had been breached and this breach is now plugged using sand bags, but flow was noted. This was noted at the vicinity of AFD TP7. Further visual assessment showed erosion of the dam wall on the upstream side. The wall has very narrow crest, 3m at most. The embankment’s downstream face is grassed. It must be noted that no survey data of the dam was available at the time of the investigation.

The soils comprising the embankment typically consist of sandy / silty clay which are soft to firm, containing quartzite and ferricrete gravel. On the natural slopes defining the dam basin, the colluvium (occasionally ferruginised) consists of fine to coarse, angular quartzite gravel and ferricrete nodules. The finer component comprises silty clay / clayey silt and sandy clay. According to the Unified Soil Classification System the embankment fill material classifies as SM while the colluvial soils classify as CL.

Based on laboratory test results, the material encountered on site has high shear strength properties and is suitable for use in a homogenous embankment.

Seepages into test pits were only encountered at AFD TP2, at the proposed spillway position, at 1.2m from surface.

Although the embankment material on site is suitable for re-use in the raising of the embankment, quantities will depend on how much can be extracted from excavations. It is not anticipated that materials can be sourced at the park due to nature of the facility. Rip-rap material would certainly be sourced from commercial sources.

Failure to access the downstream side of dam meant assessment of these areas was only limited to a distant visual observation of the vicinity. This therefore limited assessments of the downstream side of the embankment, as well as the conditions at the toe and along the spillway canal.

Contents

1 Introduction ...... 3 2 Available information ...... 3 3 Site location and description...... 3 4 Geology ...... 6 5 Climate ...... 8 6 Seismicity ...... 8 7 Site investigation rationale and methodology ...... 8 8 Investigation results ...... 10 8.1 Site walk-over ...... 10 8.2 Soil profile ...... 10 8.2.1 Embankment fill material ...... 10 8.2.2 Colluvium ...... 11 8.2.3 Ferruginised colluvium...... 11 8.3 Groundwater / seepage ...... 11

9 Laboratory test results ...... 11 9.1 Foundation indicator test results ...... 11 9.2 Compaction test results ...... 12 9.3 Shearbox test results ...... 12 9.4 Falling head permeability test results ...... 13

10 Geotechnical considerations...... 13 10.1 Foundation permeability ...... 13 10.2 Erodibility of downstream areas ...... 13 10.3 Construction materials ...... 14 10.4 Stability of slopes ...... 14 10.5 Excavatability ...... 14 10.6 Stability of excavations ...... 14

11 Closing remarks ...... 14 12 Limitations of report ...... 15 13 References...... 16

Figures

Figure 1: Location of the site ...... 4 Figure 2: View of the dam from the north (approximate centre line and position of breach are shown by yellow line and arrow, respectively) ...... 5 Figure 3: Close up view of the breach section – in the vicinity of AFD TP7. Arrows indicating approximately where water flow was noted – although clear view is obstructed by vegetation ...... 6 Figure 4: Regional geological setting of the site and stratigraphy (from published 1:250 000 geological map; Sheet 2626 West Rand, Council for Geoscience, 1986) ...... 7 Figure 5: Seismic hazard map showing peak ground acceleration (g) with 10% probability of being exceeded in a 50 year period (after SANS 10160-4:2011)...... 8 Tables

Table 1: Summary of test pit positions ...... 9 Table 2: Summary of the ground profiles present in the test pits ...... 10 Table 3: Summary of foundation indicator tests ...... 11

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Table 4: Parameters related to USCS groups ...... 12 Table 5: Summary of compaction test results ...... 12 Table 6: Summary of shearbox test results ...... 13 Table 7: Summary of falling head permeability test results ...... 13

Appendices Appendix A: Soil and rock profile description terminology Appendix B: Test pit profiles Appendix C: Drawing (504630-0000-DRG-G3-0001 - Plan of Albert's Farm Dam with test pit positions) Appendix D: Laboratory test results

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1 Introduction

The Johannesburg Roads Agency (JRA) was appointed by the Environment and Infrastructure Services Department (EISD), the implementing agent for the Water and Biodiversity Project, for rehabilitation of a number of dams within the Braamfontein West Water Management Unit in the City of Johannesburg. As part of this appointment JRA appointed Aurecon for the design of the remedial works. Aurecon Ground Engineering conducted geotechnical investigations for these dams, with the findings for Albert’s Farm Dam presented in this report.

The field investigations were conducted on the 29th of May 2019 comprising test pitting and sampling.

Albert’s Farm Dam is located in Northcliff suburb, Johannesburg, at the intersection of De La Rey Road and Zulu Street.

The following works are planned as part of the rehabilitation: • Repair of the breach section on the embankment, • Raising the embankment by a nominal 500 mm, • Reinstatement of the upslope protection, • Placing material on the downstream slope, • Construction of the spillway channel with a concrete overflow sill, and • Placing Reno mattresses for erosion immediately downstream of the sill for about 3m.

2 Available information

The available information comprised:

• The 1:250 000 scale geological map of the area (Sheet 2626 West Rand, Council for Geoscience, 1986). • An electronic file (KMZ) showing the site.

It must be noted that no geotechnical reports of any previous investigations were able to be sourced and it is unlikely that earlier geotechnical investigations were ever conducted. The desk study comprised a review of geological maps.

3 Site location and description

Albert’s Farm Dam is located in Northcliff suburb at the intersection of De La Ray Road and Zulu Street making for easy vehicular access. The site location is shown in Figure 1 below. The park, which includes the dam, is a recreational facility open to the public and is predominantly used as a dog park.

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The dam comprises an earth embankment (Figure 2) and is approximately 200m in length. The results of the dam survey show the embankment crest to be 1085mm and the height of the embankment is 5.4m and slopes at 60 degrees.

The dam is eroded on the upstream side and a previous failure of the wall was observed (Figure 3) in the vicinity of AFD TP7. Sand bags have been used to plug the breach, but flow was noted. Natural slopes around the dam are moderately sloping. The area downstream of the dam is understood to be a conservation area (pers. comm. City Parks officials).

SITE

Figure 1: Location of the site

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Figure 2: View of the dam from the north (approximate centre line and position of breach are shown by yellow line and arrow, respectively)

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Figure 3: Close up view of the breach section – in the vicinity of AFD TP7. Arrows indicating approximately where water flow was noted – although clear view is obstructed by vegetation

4 Geology

According to the 1:250 000 scale geological map (Sheet 2626 West Rand, Council for Geoscience, 1986), the area is underlain by quartzite and shale of the Orange Grove Formation of the West Rand Group, Witwatersrand Supergroup. This sequence is underlain, regionally, by basement rocks, i.e. mafics and ultramafics and the intrusive Johannesburg Dome formerly Halfway House granite and intruded by younger diabase rocks. Quartzite outcrop is recorded about 100m to the northwest of the dam. The outcrop is just under 400 m in extent and is annotated in drawing 504630-0000-DRG-G3-0001 (Appendix C). The geological setting of the site is shown in Figure 4 below. There are no major faults in the general area of the Albert’s Farm Dam.

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Figure 4: Regional geological setting of the site and stratigraphy (from published 1:250 000 geological map; Sheet 2626 West Rand, Council for Geoscience, 1986)

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5 Climate

The site is in an area with a Weinert N-value (Weinert, 1980) less than 5 but not less than 2, which indicates chemical decomposition of the underlying bedrock is the main mode of weathering. The shallow soil profiles tended to comprise fill material and transported colluvial soils; however, no residual soils were observed. Ferricrete concretions were noted in test pits excavated on the natural slopes indicating moist soil conditions associated with the climate of the area, and a seasonally-fluctuating water table.

6 Seismicity

The greater Johannesburg area is affected by natural, and induced seismic activities related to mining in the Witwatersrand. Albert’s Farm Dam is therefore associated with a seismic hazard considered moderate to high. A Peak Ground Acceleration (PGA) of about 0.2g (SANS 10160-4:2011) can be associated with the area, with a 10% probability of being exceeded in a 50-year period. The seismic map below (Figure 5), from SANS 10160- 4:2011, shows the relative position of the site to the defined seismic zones.

SITE

Figure 5: Seismic hazard map showing peak ground acceleration (g) with 10% probability of being exceeded in a 50 year period (after SANS 10160-4:2011).

7 Site investigation rationale and methodology

These investigations are considered high level investigations aimed at providing geotechnical information for the design of the remedial works. Shallow test pitting and sampling was therefore undertaken, and no deep investigations (drilling) or other investigations were included. The investigation methodology is expanded below.

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The site investigation commenced with a review of all available information of the area such as geological maps. The desktop study was followed by a site walk-over survey, test pitting and sampling.

A health and safety file was compiled as part of compliance to the South African Occupational Health and Safety Act, OHS (Act 85 of 1993) to ensure a safe working environment for Aurecon staff on site and the sub- contractors. Part of the documents contained in the file is the safe working procedures document which covers the assessment of test pits by an appointed excavation competent person prior to entry into the test pit. An inspection checklist cited in this document was used to assess the safety of the test pit excavations.

A site walk-over and the test pitting were conducted on the 29th of May 2019. Civilab was appointed for the test pitting (both machine and hand-dug) as well as the laboratory testing. Test pits AFD TP1 and AFD TP2 were excavated to depths of 2.5m and 1.6m respectively using a New Holland B90B Tractor Loaded Backhoe (TLB). Test pit AFD TP2 was terminated due to seepage occurring at 1.2m. Test pits AFD TP3 and AFD TP5 were hand excavated to a maximum depth of 1.5m. The locations of the test pits are indicated on Drawing 504630-0000-DRG-G3-0001 in Appendix C. Four planned test pits (AFD TP4, AFD TP6, AFD TP7 and AFD TP8) were not excavated during the investigation as these are falling within a conservation area. The test pit positions were recorded on site using a hand-held GPS.

The test pits were profiled by engineering geologists in accordance with the guidelines proposed by Jennings, Brink and Williams (1973). A summary of the test pit data is given in Table 1 and detailed ground profile descriptions are attached in Appendix B of this report.

Representative samples were taken from the test pits and submitted to SANAS-accredited laboratory, Civilab (Pty) Ltd, for classification and geotechnical testing. Tests conducted included:

• Foundation indicator tests (comprising of grading and hydrometer analyses, Atterberg limits and Linear Shrinkage);

• Proctor compaction including Maximum Dry Density (MDD) and Optimum Moisture Content (OMC);

• Quick direct shear tests; and • Falling head permeability tests. Laboratory test results are summarised in Section 9 and detailed test results sheets attached to Appendix D.

Table 1: Summary of test pit positions

Test Pit No. SA Lo 29 WGS84 Depth (m) Remarks

X Y

AFD TP1 2894431 102846 2.5 Target depth reached, test pit located at proposed spillway AFD TP2 2894444 102848 1.6 Terminated due to seepage – excavation unsafe; test pit located at proposed spillway AFD TP3 2894465 102845 1.5 Target depth reached, test pit located at the crest AFD TP4 2894484 102878 - Test pit not excavated

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Test Pit No. SA Lo 29 WGS84 Depth (m) Remarks

X Y

AFD TP5 2894527 102875 1.5 Target depth reached, test pit located at slope of embankment AFD TP6 2894511 102862 - Test pit not excavated

AFD TP7 2894579 102889 - Test pit not excavated

AFD TP8 2894508 102817 - Test pit not excavated

8 Investigation results

8.1 Site walk-over

During the site walk-over outcrop of Orange Grove Formation quartzite was noted approximately 100m northwest of the dam. The outcrop was not assessed further but was noted as a probable indication of the underlying geology. Quartzite gravel is scattered on the surface in the vicinity of AFD TP1 and AFD TP2. The previous dam wall breach was also noted (Figure 3). Erosion of the upstream slope is also noted as a result of wave action against the embankment. It is understood that protection of this upstream face of the embankment is proposed as part of the remedial works.

8.2 Soil profile

Embankment fill material and colluvium (occasionally ferruginised) were encountered in the test pits. The colluvium was encountered on the natural slopes to the north of the dam (at AFD TP1 and AFD TP2). The fill material is predominantly clayey containing quartzite gravel and scattered ferricrete nodules. The quartzite and ferricrete gravel are also encountered in the natural slopes. The details of the horizons in each test pit are summarised in the table below.

Table 2: Summary of the ground profiles present in the test pits

Test Pit No. Embankment fill (m) Colluvium (m) Ferruginised colluvium (m) AFD TP1 0.0 - 0.5 0.5 - 2.5+

AFD TP2 0.0 - 1.6+

AFD TP3 0 0 - 1.5+

AFD TP5 0.0 - 1.5+

8.2.1 Embankment fill material The embankment fill material comprises slightly moist to moist, soft and firm, sandy and / silty clay containing occasional to abundant fine and medium to coarse, angular, quartzite gravel and scattered ferricrete concretions. A 0.65m thick layer of slightly moist, medium dense, clayey sand was encountered at a depth of 0.95m below the sandy / silty clay at AFD TP3.

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The different fill layers are of various thicknesses, ranging between 0.15 to 0.65m with a maximum thickness of 1.25m recorded at Test Pit AFD TP5, the slightly moist to moist, soft sandy clay with occasional medium to coarse angular and scattered ferricrete nodules.

8.2.2 Colluvium Colluvium was encountered at Test Pit AFD TP1 from surface to 0.5m and at Test Pit AFD TP2 from surface to 1.6m. The coarser fraction comprises gravel described as fine to coarse, angular, closely packed, hard quartzite gravel in a matrix of slightly moist, silty clay with abundant rootlets. The overall consistency is medium dense. While fine colluvium comprises silty clay / clayey silt and sandy clay.

8.2.3 Ferruginised colluvium The ferruginised colluvium was encountered at Test Pit AFD TP1 from 0.5 to 2.5m. comprising moist, soft, silty clay with significant medium to coarse, angular, quartzite gravel and ferricrete nodules. A pinholed structure was noted in this layer.

8.3 Groundwater / seepage

Seepage was encountered at AFD TP2, the test pit located at the proposed spillway position. The seepage occurred at a depth of 1.2m below surface. The test pit was actually moved from the proposed position due to wet conditions being noted. Thus, the general area is defined by such conditions which possibly results from overflow.

9 Laboratory test results

The laboratory test results are summarised and discussed below, and the detailed test results are attached in Appendix D.

9.1 Foundation indicator test results

Disturbed soil samples of representative horizons were taken for laboratory testing to confirm the compositions of the materials. The results are summarised in the table below.

Table 3: Summary of foundation indicator tests

TP Depth Material Particle Size % Atterberg Limits % GM AASHTO/ type USCS No (m) Clay Silt Sand Gravel LL PI LS classification; expansion potential

AFD 1.50-2.50 Ferruginised 25 34 29 12 41 17 9.0 0.69 A-7-6 (9) / CL; TP1 colluvium Medium

AFD 0.25-1.50 Fill material 19 17 26 38 51 20 7.5 1.56 A-7-5 (2) / SM; TP5 Low AASHTO – American Association of State Highway and Transportation Officials USCS – Unified Soil Classifications System LL – Liquid Limit PI – Plasticity Index LS – Linear Shrinkage GM – Grading Modulus SM – Silty sands, sand-silt mixtures CL– Inorganic clays of low to medium plasticity

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gravelly clays, sandy clays, silty clays, lean clays

Based on the table above, the results show the following:

• The results show that the ferruginised colluvial soils contain 25% clay and 34% silt. The coarse fractions consist of 29% sand and 12 gravel. According to the Unified Soil Classification System (USCS) the material classifies as CL. In accordance to the method proposed by Van der Merwe (1973) this material has a medium potential for expansion.

• The embankment fill material is classified as SM according to the Unified Soil Classification System (USCS). The material consists of 19% clay and 17% silt. The gravel component constitutes 38% of the coarse fraction while sand makes up 26%. In accordance to the method proposed by Van der Merwe (1973) this material has a low potential for expansion. The USCS grouping of soils is useful in providing estimations of friction angles of the materials as well as other parameters, i.e. unit weight. These parameters are presented below for the materials encountered on site.

Table 4: Parameters related to USCS groups

Test Pit No. Material USCS group Classification Unit weight Friction Cohesion origin (kN/m3) angle (º) (kPa) AFD TP1 Ferruginised CL Clayey sand, 20 (± 1.5) 27 (± 4) 20 (± 10) colluvium many fines AFD TP5 Embankment SM Silty sand; 20 (± 2.0) 34 (± 3) 0 fill material many fines Note: The soil classes and estimated properties have been adapted from Krahenbuhl and Wagner (1983).

9.2 Compaction test results

Compaction tests were also conducted on selected samples to determine the compaction properties of the materials and the results are summarised in the table below.

Table 5: Summary of compaction test results

TP No. Material type Depth (m) Standard Proctor

MDD (kgm3) OMC %

AFD TP05 Embankment fill material 0.25-1.50 1572 22.9

MDD – Maximum Dry Density OMC – Optimum Moisture Content

According to the table above, embankment fill material has a Maximum Dry Density (MDD) of 1572 kg/m3 with an Optimum Moisture Content (OMC) of 22.9%. These values reflect typically near-minimum MDD values for a homogeneous embankment, while the corresponding OMC is naturally near the maximum desirable. Note it is assumed that the existing structure is a homogeneous embankment. This is not confirmed.

9.3 Shearbox test results

Quick undrained shear testing was conducted on a disturbed sample of embankment fill material to determine the strength parameters of these materials. The test was conducted on a sample remoulded to 90% standard Proctor compaction. The results are summarised as follows:

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Table 6: Summary of shearbox test results

TP No. Material type Depth (m) Shear strength parameters

Cu (kPa) Nu (deg)

AFD TP05 Fill material 0.25-1.50 60.5 45.3

Cu = Cohesion intercept Nu = Angle of shearing resistance

Based on the table above, the results show that the embankment fill material exhibit high shear strengths. It must be noted that the material contains a high gravel content.

9.4 Falling head permeability test results

Falling permeability testing was conducted on a disturbed soil sample of embankment fill material remoulded to 90% standard Proctor compaction. The sample was saturated and tested under a load of 100kPa. Densities are reported under this load.

Table 7: Summary of falling head permeability test results

TP No. Material type Depth (m) Dry density Coefficient of Permeability (m/s) (kg/m3) Minimum Maximum Average

AFD TP05 Fill material 0.25 - 1.50 1326 1.0E-08 1.6E-08 1.2E-08

An average coefficient of permeability value of 1.2 E-08m/s was recorded which would be suitable for a homogeneous embankment.

10 Geotechnical considerations

10.1 Foundation permeability

The embankment fill material recorded an average coefficient of permeability value of 1.2 E-08 indicative of practically impervious material. No seepage occurred at test pits located on fill material. Seepage was noted on the test pit located at the proposed spillway (AFD TP2).

10.2 Erodibility of downstream areas

The area downstream of the dam was not accessed during the investigation because it is regarded as a conservation area, and possible evidence of erosion could not be observed. The area downstream is however well vegetated. Any embankment that is overtopped for a sufficient duration, by a significant flow, must be considered erodible.

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10.3 Construction materials

The laboratory test results indicate the materials encountered on site have a well distributed mix of fines and coarse fractions. Further test results, i.e. shearbox and permeability show that the embankment fill material has high shear strength properties and practically impervious. These materials of the existing embankment would therefore be suitable for re-use within the rehabilitated homogeneous embankment.

Investigation for rip-rap material did not form part of the scope of these investigations. Environmental constraints will surely not entertain sourcing rip-rap from the local outcrop, and commercial sources would be the only logical option.

10.4 Stability of slopes

The natural slope to the north of the dam is characterised by a moderate gradient with scattered gravel on surface in some places. It is well grassed, though the grass was cut at the time of the investigation. No evidence of instability was observed, and none is expected.

10.5 Excavatability

The excavation conditions across the site can be described as “Soft Excavation” according to SABS 1200 DA- 1998 specification; at least in terms of the depths attained by the shallow test pits. With outcrop in the vicinity it might be expected that deeper excavations might encounter rock that would require blasting.

10.6 Stability of excavations

Sidewall collapse was encountered in one of the test pits, AFD TP2, during the investigation, and this was linked to seepage.

It must be noted that this assessment is based on shallow excavation which was backfilled immediately. As part of safe practice during construction, assessment of the stability of excavations would be required by an appointed competent geotechnical person.

11 Closing remarks

It must be noted that these investigations have been quite limited as a result of the access restrictions. As a consequence, the information gathered, and the information gathered is also sparse.

Although obvious, it is worth stating that during the re-construction programme, a comprehensive laboratory testing schedule is implemented to confirm the materials used comply with specifications.

It is worth emphasizing that with the shallow water table in places, particularly if the dam level is not lowered, that the stability of excavations might be compromised. Great caution must be exercised in this regard, and slope stability must be assessed regularly by a geotechnical-competent person.

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12 Limitations of report

1. Aurecon Ground Engineering has prepared this report for the use of our Client, Johannesburg Roads Agency (JRA) and our Aurecon dam design colleagues. The report has not been prepared for use by parties other than the Client, and the Client’s respective consulting advisors. 2. This report has been written with the express intent of providing enough information for the design of the remedial works. The investigation has been conducted in accordance with generally accepted engineering practice, and the opinions and conclusions expressed in the report are made in good faith based on the information available to Aurecon Ground Engineering at the time of preparing this report. 3. There are always some variations in subsurface conditions across a site due to geological conditions that cannot be defined fully even by exhaustive investigation. Hence, it is possible that the measurements and values obtained from sampling and testing during the investigation may not represent the extremes of conditions which exist within the site. The precision with which subsurface conditions are identified depends on the method of excavation, the frequency and recovery of samples, the method of sampling, and the uniformity of the subsurface conditions. Subsurface conditions at other than the test pit positions may vary from the conditions encountered in the test pit locations. 4. Further, subsurface conditions, including groundwater levels can change over time. The groundwater conditions described in this report refer only to those observed at the place and time of observation noted in the report. These conditions may vary seasonally or as a consequence of construction activities in the area. This should be borne in mind, particularly if the report is used after a protracted delay or a period of protracted climatic conditions. 5. Should conditions exposed at the site during subsequent investigation or construction works vary significantly from those provided in this report, we request that Aurecon Ground Engineering be informed and have the opportunity to review any of the findings or conclusions of this report. It is highly recommended that during construction the site conditions be inspected by a representative of Aurecon Ground Engineering to confirm the geotechnical interpretations in this report. 6. Unless otherwise stated, this report does not address potential environmental hazards, or groundwater contamination that may be present. In addition to soil variability, fill material of variable physical and chemical composition can be present over portions of the site or on adjacent properties 7. The test pit logs represent the subsurface conditions at the specific test location only. Boundaries between zones on the logs are not often distinct, but rather are transitional and have been interpreted. The soil descriptions in this report are based on commonly accepted methods of classification and identification employed in geotechnical practice, as stated in this report. Classification and identification of soil involves judgement, and Aurecon Ground Engineering infers accuracy in the classification and identification methods to the extent that is common in current geotechnical practice, and within the limitations of the ground investigation that was performed. 8. It is recommended that further geotechnical input from Aurecon Ground Engineering should be sought as the project moves into the next phase to confirm that the geotechnical assumptions made in this report are compatible with the structural performance requirements and are being applied appropriately.

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13 References

• Jennings, J. E. B, Brink, A.B.A and Williams, A. A. B, (1993). Revised Guide to Soil Profiling for Civil Engineering Purposes in Southern Africa. The Civil Engineer in SA, p 3-12. January 1973.

• Kranehbuhl, J. and Wagner, A (1983). Survey, design, and construction of trial suspension of bridges for remote areas, SKAT, Swiss Center for Appropriate Technology in St Gallen, Switzerland.

• SABS 1200D: 1988 Standardised specification for civil engineering construction. D: Earthworks, South African Bureau of Standards, Pretoria.

• SANS 10160-4:2009 (2011). South African National Standard: Basis of structural design and actions for buildings and industrial structures. Part 4: Seismic actions and general requirements for buildings. ISBN 978-0-626.

• Terzaghi, K. Peck, R. B and Mesri, G, (1996). Soil Mechanics in Engineering Practice. 3rd edition. John Wiley and Son Inc.

• Weinert (1980). The natural road construction materials of southern Africa. National Institute for Transport and Road Research Pretoria.

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Appendix A: Soil and rock profile description terminology

STANDARD DESCRIPTIONS USED IN SOIL PROFILING

1. MOISTURE CONDITION 2. COLOUR Term Description Dry The Predominant colours or colour combinations are described including secondary coloration Slightly Requires addition of water to reach optimum moist moisture content for compaction described as banded, streaked, blotched, Moist Near optimum content mottled, speckled or stained.

Very Moist Requires drying to attain optimum content Wet Fully saturated and generally below water table 3. CONSISTENCY 3.1 Non-Cohesive Soils 3.2 Cohesive Soils Term Description Term Description Very Crumbles very easily when scraped with Very soft Easily penetrated by thumb. Sharp end of pick Loose geological pick can be pushed in 30 - 40mm. Easily moulded by fingers. Loose Small resistance to penetration by sharp end of Soft Pick head can easily be pushed into the shaft of geological pick handle. Moulded by fingers with some pressure. Medium Considerable resistance to penetration by sharp Firm Indented by thumb with effort. Sharp end of pick Dense end of geological pick can be pushed in up to 10mm. Can just be penetrated with an ordinary spade. Dense Very high resistance to penetration to sharp end of Stiff Penetrated by thumbnail. Slight indentation geological pick. Requires many blows of hand produced by pushing pick point into soil. Cannot pick for excavation. be moulded by fingers. Requires hand pick for excavation. Very High resistance to repeated blows of geological Very Stiff Indented by thumbnail. Slight indentation Dense pick. Requires power tools for excavation produced by blow of pick point. Requires power tools for excavation. 4. STRUCTURE 5. SOIL TYPE 5.1 Particle Size Term Description Term Size ( mm ) Intact Absence of fissures or joints Boulder >200 Fissured Presence of closed joints Pebbles 60 – 200 Shattered Presence of closely spaced air filled joints giving Gravel 60 – 2 cubical fragments Micro- Small scale shattering with shattered fragments Sand 2 – 0,06 shattered the size of sand grains Slickensided Polished planar surfaces representing shear Silt 0,06 – 0,002 movement in soil Bedded Many residual soils show structures of parent Clay <0,002 Foliated rock. 6. ORIGIN 5.2 Soil Classification 6.1 Transported Soils Term Agency of Transportation 0 Colluvium Gravity deposits 1 00 10 9 0 Talus Scree or coarse colluvium 20 8 0 Hillwash Fine colluvium 30 Colluvial River deposits CLAY 7 0 40 6 0 SAND Aeolian Wind deposits CLAY SLIGHTLY SLIGHTLY 50 SANDY SILTY 5 0 Litoral Beach deposits CLAY CLAY SLIGHTLY 60 4 0 Estuarine Tidal – river deposits SA N DY A N D SILTY CLAY 70 SANDY SILTY 3 0 Lacustine Lake deposits CLAY SANDY SILTY CLAY CLAY 8 0 2 0 6.2 Residual soils CLAYEY SANDY CLAYEY SAND CLAYEY SILT SILT These are products of in-situ weathering of rocks and are 90 1 0 SLIGHTLY CLAYEY SAND SA N DY S ILT SILT described as e.g. Residual Shale 1 00 SAND S I L TY S A N D 0 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 90 1 00

6.3 Pedocretes SILT Formed in transported and residual soils etc. calcrete, silcrete, manganocrete and ferricrete.

SUMMARY OF DESCRIPTIONS USED IN ROCK CORE LOGGING

1. WEATHERING

Term Symbol Diagnostic Features Residual Soil W5 Rock is discoloured and completely changed to a soil in which original rock fabric is completely destroyed. There is a large change in volume. Completely W5 Rock is discoloured and changed to a soil but original fabric is mainly preserved. There may be Weathered occasional small corestones. Highly W4 Rock is discoloured, discontinuities may be open and have discoloured surfaces, and the original Weathered fabric of the rock near the discontinuities may be altered; alternation penetrates deeply inwards, but corestones are still present. Moderately W3 Rock is discoloured, discontinuities may be open and will have discoloured surfaces with Weathered alteration starting to penetrate inwards, intact rock is noticeably weaker than the fresh rock. Slightly W2 Rock may be slightly discoloured, particularly adjacent to discontinuities, which may be open and Weathered will have slightly discoloured surfaces, the intact rock is not noticeably weaker than the fresh rock. Unweathered W1 Parent rock showing no discolouration, loss of strength or any other weathering effects. 2. HARDNESS 3. COLOUR

Classification Field Test Compressive Strength Range MPa

Very Soft Can be peeled with a knife. Material 1 to 3 Rock crumbles under firm blows with the The predominant colours or colour combination sharp end of a geological pick. are described including secondary colouration Soft Rock Can be scraped with a knife, 3 to 10 described as banded, streaked, blotched, indentation of 2 to 4 mm with firm blows of the pick point. mottled, speckled or stained. Medium Hard Cannot be scraped or peeled with a 10 to 25 Rock knife. Hand held specimen breaks with firm blows of the pick. Hard Rock Point load tests must be carried out in 25 - 70 order to distinguish between these classifications Very Hard These results may be verified by 70 - 200 Rock uniaxial compressive strength tests on selected samples. Extremely >200 Hard Rock 4. FABRIC

4.1 Grain Size 4.2 Discontinuity Spacing Term Size (mm) Description for: Bedding, foliation, Spacing (mm) Descriptions for joints, laminations faults, etc. Very Coarse >2,0 Very Thickly Bedded > 2000 Very Widely Coarse 0,6 – 2,0 Thickly Bedded 600 – 2000 Widely Medium 0,2 – 0,6 Medium Bedded 200 – 600 Medium Fine 0,06 – 0,2 Thinly Bedded 20 – 200 Closely Very Fine < 0,06 Laminated 6 – 20 Very closely Thinly Laminated <6 5. ROCK NAME 6. STRATIGRAPHIC HORIZON

Classified in terms of origin: IGNEOUS Granite, Diorite, Gabbro, Syenite, Diabase, Dolerite, Trachyte, Andesite, Basalt. Identification of rock type in terms of stratigraphic METAMORPHIC Slate, Quartzite, Gneiss, Schist, horizons. SEDIMENTARY Shale, Mudstone, Siltstone, Sandstone, Dolomite, Conglomerate, Tillite, Quartzite, Limestone.

Appendix B: Test pit profiles

HOLE No: AFDTP01 Johannesburg Road Agency Sheet 1 of 1 Geotechnical Investigation for Alberts Farm Dam JOB NUMBER: 504630

Scale 0.00 1:20 Fine to coarse, angular, closely packed, hard quartzite gravel in a matrix of slightly moist, dark brown, silty CLAY with abundant rootlets. Overall consistency MEDIUM DENSE. Colluvium.

0.50 Moist, dark yellow orange, speckled black, SOFT, intact, silty CLAY with abundant ferricrete nodules and significant angular medium to coarse gravel and rootlets. Ferruginised Colluvium.

1.50 Moist, dark yellow orange, speckled black, SOFT, intact, silty CLAY with less abundant ferricrete nodules. Ferruginised Colluvium.

Disturbed sample

2.50

NOTES:

Final depth at 2.5m on ferruginised colluvium Dislodgement of coarse gravel into test pit No groundwater or seepage encountered FI sample taken at 1.5-2.5m Coarse gravel in vicinity of hole

CONTRACTOR: INCLINATION: ELEVATION: MACHINE: New Holland B90B TLB DIAM: X COORD: 2894431 PROFILED BY: A. Nxumalo & P. van Helsdingen DATE DRILLED: 5/29/2019 Y COORD: 102846 TYPE SET BY: DATE PROFILED: 5/29/2019 HOLE No: AFDTP01 ALBERTS FARM DAM.GPJ Report ID: _ZA TRAIL PIT LOG || Project: ALBERTS FARM DAM.GPJ || Library: GINT STD AGS 4_0_SA.GLB || Date: July 25, 2019 July 4_0_SA.GLB Date: AGS || Library: STD GINT || DAM.GPJ FARM ALBERTS Project: LOG PIT || _ZA TRAIL Report ID: HOLE No: AFDTP02 Johannesburg Road Agency Sheet 1 of 1 Geotechnical Investigation for Alberts Farm Dam JOB NUMBER: 504630

Scale 0.00 1:20 Coarse to fine, angular, closely packed, hard quartzite gravel with a matrix of slightly moist, silty CLAY with abundant rootlets. Colluvium.

0.70 Slightly moist, orange brown, silty CLAY/clayey SILT. Colluvium.

1.20 Very moist to wet, yellow brown, sandy CLAY. Colluvium.

1.60

NOTES:

Test pit terminated at 1.6m on colluvium Seepage encountered at 1.2m Sidewalls unstable (collapsing) Test pit not entered due to unsafe conditions - material profiled from stockpile Test pit moved 8m from the original position

CONTRACTOR: INCLINATION: ELEVATION: MACHINE: New Holland B90B TLB DIAM: X COORD: 2894444 PROFILED BY: A. Nxumalo & P. van Helsdingen DATE DRILLED: 5/29/2019 Y COORD: 102848 TYPE SET BY: DATE PROFILED: 5/29/2019 HOLE No: AFDTP02 ALBERTS FARM DAM.GPJ Report ID: _ZA TRAIL PIT LOG || Project: ALBERTS FARM DAM.GPJ || Library: GINT STD AGS 4_0_SA.GLB || Date: July 25, 2019 July 4_0_SA.GLB Date: AGS || Library: STD GINT || DAM.GPJ FARM ALBERTS Project: LOG PIT || _ZA TRAIL Report ID: HOLE No: AFDTP03 Johannesburg Road Agency Sheet 1 of 1 Geotechnical Investigation for Alberts Farm Dam JOB NUMBER: 504630

Scale 0.00 1:20 Slightly moist, yellow brown, SOFT, slightly sandy CLAY with abundant fine gravel (angular quartzite gravel and ferricrete) and roots. Fill.

0.50 Slightly moist (dry), dark reddish brown to red brown, 0.65 SOFT, silty CLAY with roots. Fill. Slightly moist, dark grey, FIRM, sandy CLAY with roots. Fill. 0.95 Slightly moist, dark brown, MEDIUM DENSE, clayey SAND with roots. Fill.

1.60

NOTES:

Final depth at 1.6m on fill Sidewall stable No groundwater or seepage encountered

CONTRACTOR: INCLINATION: ELEVATION: MACHINE: Hand dug DIAM: X COORD: 2894465 PROFILED BY: A. Nxumalo & P. van Helsdingen DATE DRILLED: 5/29/2019 Y COORD: 102845 TYPE SET BY: DATE PROFILED: 5/29/2019 HOLE No: AFDTP03 ALBERTS FARM DAM.GPJ Report ID: _ZA TRAIL PIT LOG || Project: ALBERTS FARM DAM.GPJ || Library: GINT STD AGS 4_0_SA.GLB || Date: July 25, 2019 July 4_0_SA.GLB Date: AGS || Library: STD GINT || DAM.GPJ FARM ALBERTS Project: LOG PIT || _ZA TRAIL Report ID: HOLE No: AFDTP05 Johannesburg Road Agency Sheet 1 of 1 Geotechnical Investigation for Alberts Farm Dam JOB NUMBER: 504630

Scale 0.00 1:20 Slightly moist, dark olive, SOFT, sandy CLAY. Fill.

0.25 Slightly moist, dark yellow orange, SOFT, sandy CLAY with occasional angular medium to coarse quartzite gravel and scattered ferricrete nodules. Fill.

Disturbed sample

1.50

NOTES:

Final depth at 1.5m on fill Sidewall stable No groundwater or seepage encountered FI, proctor, shearbox and permeability sample taken at 0.25-1.5m Test pit on embankment slope

CONTRACTOR: INCLINATION: ELEVATION: MACHINE: Hand dug DIAM: X COORD: 2894527 PROFILED BY: A. Nxumalo & P. van Helsdingen DATE DRILLED: 5/29/2019 Y COORD: 102875 TYPE SET BY: DATE PROFILED: 5/29/2019 HOLE No: AFDTP05 ALBERTS FARM DAM.GPJ Report ID: _ZA TRAIL PIT LOG || Project: ALBERTS FARM DAM.GPJ || Library: GINT STD AGS 4_0_SA.GLB || Date: July 25, 2019 July 4_0_SA.GLB Date: AGS || Library: STD GINT || DAM.GPJ FARM ALBERTS Project: LOG PIT || _ZA TRAIL Report ID:

Appendix C: Drawing (504630-0000-DRG-G3-0001 - Plan of Albert's Farm Dam with test pit positions)

S911 S908

S513

S777

S772

S700

T0146 S311

T0145 S639 MH

S773

57 S257

S774 S515 S310

S775 S776

S309

S701 S699

S624 58

37 S640

S308

S514 T0152 T0151 S519 707

S516

S241

S702 S703 BS3 S258

S698

S641 BS03TTBS03BS03TBS04a S298 61

S704

S299

63 62

S517

S300

S697

T0153T0154

S301

S623

S302 S520 S303

S518 S304

S306

S307

S696 S305

S642

S259

S297

S694 S622

S621

S521

S693

T0155 S695 T0156

S643

S522 S692 S296

S620 50

S293 S295

S292

39 S294

53 S260

S644

S291 15

S648 S240

S523

T0157 S649

S619 T0158 S290 706

S284

S283

S282 S524 107108S002 S646

S281

S645 T045 S285 S289 S286 110S001 109

S280

S287

S288 49

S279

T044 M01

BS04

S618

T042 T046

S261

T043 14

112

S647

T041 S650

S525 T047 111

S262

S617 S266

41 42 S267 S263

S006 43 117

40 S265 S264 48

M08

S268 M02

T048 113 44

T049

S269 S270 M09

114 S526 45 M10 T040

S271

S272

S273

S007 116 M06 47 S003 M05 S005

M185 M07 46

S274

FootS004115 Bridge M03 S616 S528

M11

S527 T050

S275

T039 M04

S278 S853

T118

S530

S611 S615

S529 M186 S610

S186 S531

M12

S276

S854 S852

M184

S185

S277

S011

T051

S532

S533 T117

S614

S012

S239 M187

S187

S535 T119

S851

S855

S613

S010

S008

S609 S009

S534

S184

S536

M183

S188

S539 S538

S850

S857

T120

M13 S612

S856 S849

T116

S540

GCP5TGCP5 S544 S905 M188 S906

S545

S859 T052 M18 725 S858

S537

S551 S189

S183

S562

S236 S150

S237

S238

S552 S541 T121

GCP4TS235GCP4

S847 S234

S543

S860

S560

M189 S861

S848

T053

S561 S846

S546 M182 S553

S549

S844 S233 T115

M17 S862

M14 S559

S542

S182

S845

M190

S793

S149 S550

S190

S151

S232

S228

S231

S841 S581

S547 S548 S558 T054 S580

S838

M181 S013

S863

S554 S794

S843 S230

M15

T055 M191

S840

M16

S555 S842

S106

S556

S837 S229

S557

T0159

S795 S152 S148

S864 S579 S839

S181

T114

S563

S836 S571 726

S564

S191 S865

M192 T058

S227

M19

S796

T0172 M180

M20

S835

S578

T057

S572 T113 S834

S153

T101

S147 T103 S797 S107 T056 T102

S866

S014 S573 M138

S570

S226 T0160

S180

S565

S798

MF070MF071 T0171

S104 S577

M21

S192

M22

S867

S225

S833

M179

BS05TBS05

S574 M137

S015

T122

M193

S799

S103 T059

M139 MF068 MF069

S146 S569 T0170

S566

T060

S179 S868

S105

T061

T112

S193

S575

S832 S814

S800

MF067 MF066

S102

S108

S831

M178

S792

M136 S810

M23 M24 S869

S567

M194

S145

T037

M140

S801 S811

S223

S830

S813

S568

T123 S016

S178

S809

S829 M25

M135

M26

S870

M177

S224 S109

S802

T036 S815 S828

S812 S101

S808

S194 T0161

T0169

S144 M141

MF051

MF050 S177

S827

S017 S222 T100

T099 T098 T111

MF043 MF042

MF052

M195 M134

MF044 MF048 MF045 MF049

T125

T032 S816 S871

MF047 MF046

T062 T064 T035

S807 T063

S826 T124

S803 MF054 MF055

M176 M28

M27

S110

MF053

S143

S872

S817 M142

T0162

MF057MF056 S195 S221

S100

S176 S825

S806

BS06TBS06

S804 MF058 MF059 T0168

S788

T033

S154 S873

M196

M133

MF060 MF061

S824

M29

T027

M30 MF14

MF063

MF062

S818

S142 S805

T0163

S789

S874

T110

MF01

M175

S823 M143

S786 S819 S787

S219 S196 S175

S111

S099

MF064 T0173 MF065

S822 T0167

S220 T034 S790

MF13

S875

MF15

S821

M31

S035

S820

M32 MF02

M197

S155 S791

T0164

MF12

M132

S018

T026

MF16

MF11

S785

T065

MF03 S876 S782

MF10 S141 T066

M144

T067

S034

S174

MF09

T0174

T0166 S783

T0179

S112

M33 S019

S877

M174

M34 S197

MF17 MF08

T109

S098

T097 S784 T095

T0165

T096

S156

M198 T0175

T025

MF07

S218 MF26

MF04

MF29 MF30

M145 MF31

M36

MF28

M131

S140

MF18 M35

S173

S878

T0178 T0176

MF27

S113 MF25

M173 S097

GCP3TGCP3

T016 S217 MF32

MF05 M37

MF06

S198

M199

T024

MF19 MF33 MF34

T068

T069

T108

T070

S157

M130

M146

S139

T0177 MF35

MF24

M38

S020

M39

S215

MF20

S172

M172

S114

S096 S095

T017

BS01TBS01

T093 T092 S216

T094

S199

M129

MF41

MF36

M200

M147

MF23

MF40 BS1 S879 S158

MF21

M41

S021 M40

T023

S138

MF39

M128

S171

MF22

T107 M171

S094 MF37

MF38

S115

S880

S200

S898

M42

M43

T005 S214

S903

M148 M201

S899

S033

S159

T071

S213

S901

T072

S902 S904 T018 S881 S900

S170

GCP2 M170 GCP2T T073

S137

M127 T022

S093 S092

S032

S116

S201

M149

T126 M202

M44

S882

T004

S883

S160

M45 T089

T090

S022 T091

M169

S136

S212 M126

T019 S031

S202

M46

S211 S884

M48

M47

S169

M203

T021 S897

M150

S091

S896

S885 S117

S135

S161

S895

M50 T076 M49

T106

T003 T075

S168

S203 T020

M168

M125

T074

M151 S894

S209

S893

S118 S119

S210

S208

S892

S090

M52

S023 M51

M204

S167

S134 T088

S162

T087

BS1 T086

S204 T002

BS02TBS02

T105 S890

S891

M124 M123 S027 S030 M152

S120 T079

S028

M167

S024

M211

M53

S889

M210

M209 M208

M163

M205

T078

M54

S026

T077

T080

S166

S207 T085 S025 S071

S205 S089

T081 M56

T001

M62

M122 M55

T084

M61

M57

M60

M59

M153

T082 S206

S121

M58 S133

T083

M65

S888 S070

M166 M102

T104 S886

M64 S072

M206 M66

S037

S887

S036 S038

S165 M67 M63

M121

S039

S069

M68

S088 S122

M69

S132 M103

S040

M154

M70

S046

M74

M165 S041 M73

S073

S068 M72

M101

M162

S164

M120

S045 S042 M71

M75

M77 S123

M76

M104

S087 S043

M78

S047 S044

M164 S048

S131

M155 S074

S067

S163

M119

M79

M105

M161

M160

S075

S124

S086

M156

S130

GCP1TGCP1

M80

M106

M100

S129

S066

M118

S049

M159

S125 S076

M81

M99

M107

S085

S084

M157

S128 CLIENT REV DATE REVISION DETAILS APPROVED SCALE SIZE DESIGN PROJECT REHABILITATION OF ALBERT'S FARM DAM A 07/2019 ISSUE FOR REVIEW AS SHOWN A1 NOT FOR CONSTRUCTION BRAAMFONTEIN WEST WATER MANAGEMENT UNIT DRAWN APPROVED GEOTECHNICAL INVESTIGATION S. NKOSI . TITLE DESIGNED LAYOUT OF TEST PITS A. NXUMALO - CHECKED PROJECT No. WBS TYPE DISC NUMBER REV DRAWING No. G. DAVIS 504630 0000 DRG G3 0001 A

Appendix D: Laboratory test results

Client : CIVILAB (PTY) LTD - CENTURION Address : P O BOX 7661 Client Reference : : CENTURION Order No. : : 46

Attention : Date Received : 06/06/2019 Facsimile : 012-653-0997 Date Tested : 06/06/2019 - Current E-mail : [email protected] Date Reported : 05/07/2019

Project : Rehabilitation of Braamfontein West Water Management Unit- Alberts Farm Project No. : 2019-B-840 Report Status : Final Page : 1 of 5

Herewith please find the test report(s) pertaining to the above project. All tests were conducted in accordance with prescribed test method(s). Information herein consists of the following: Test(s) conducted / Item(s) measured Qty. Test Method(s) Authorized By** Page(s)

Moisture Density Relationship 1.000 ASTM D698 S Pullen/B Mvubu 3-3

Relative density of soil (SG) 1.000 SANS 3001 AG23 B Mvubu 2-2

Atterberg Limits <0.425mm 1.000 SANS 3001 GR10 S Pullen/B Mvubu 2-2

Sieve Analysis 0.075mm 1.000 SANS 3001 GR1 S Pullen/B Mvubu 2-2

Hydrometer Analysis 1.000 SANS 3001 GR3 S Pullen/B Mvubu 2-2

Falling Head Permeability 1.000 K H Head J Marques 1File; 1Page

Direct Shearbox 1.000 BS 1377 Part 5 J Marques 1 File; 1Page

Any test results contained in this report and marked with * in the table above are "not SANAS accredited" and are not included in the schedule of accreditation for this laboratory.

Any information contained in this test report pertain only to the areas and/or samples tested. Documents may only be reproduced or published in their full context.

While every care is taken to ensure that all tests are carried out in accordance with recognised standards, neither Civilab (Proprietary) Limited nor its employess shall be liable in any way whatsoever for any error made in the execution or reporting of tests or any erroneous conclusions drawn therefrom or for any consequences thereof.

All interpretations, Interpolations, Opinions and/or Classifications contained in this report falls outside our scope of accreditation. The following parameters, where applicable, were excluded from the classification procedure: Chemical modifications, Additional fines, Fractured Faces, Soluble Salts, pH, Conductivity, Coarse Sand Ratio, Durability (COLTO: G4-G9). The following parameters, where applicable, were assumed: Rock types were assumed to be of an Arenaceous nature with Siliceous cementing material.

Unless otherwise requested or stated, all samples will be discarded after a period of 3 months.

This report is completely confidential between the parties (Civilab and Civilab`s client) and shall not be disclosed to anybody else, unless agreed upon in writing or made publicly available by the client or required to make available by law.

Deviations in Test Methods: Technical Signatory:

Signature: **All results are authorized electronically by approved managers and/or technical signatories.

Civilab (Proprietary) Limited. Registration No: 1998/019071/07 Page 1 of 3 Client : CIVILAB (PTY) LTD - CENTURION Date Received: 06/06/2019 Project : Rehabilitation of Braamfontein West Water Management Unit Date Reported: 04/07/2019 Project No : 2019-B-840 Page No. : 2 of 5 FOUNDATION INDICATOR Laboratory Number 1 POTENTIAL EXPANSIVENESS Field Number TP5 60 Client Reference AFD Depth (m) 0.25-1.50 50

Position 40 X Very High Coordinates Y 30 High 20 Description Medium Low

10 Overall Plasticity Index Plasticity Overall Aditional Information Alberts Farm 0 Calcrete / Crushed 0 10 20 30 40 50 60 70 80 Stabilizing Agent Clay Fraction of Whole Sample Moisture Content & Relative Density Moisture Content (%) USC PLASTICITY CHART Relative Density (S.G.) 2.932 60 Sieve Analysis (Wet Prep) SANS 3001 GR1 100 mm 100 50 75 mm 100 63 mm 100 50 mm 100 40 37.5 mm 100 28 mm 100 30 20 mm 100 14 mm 89 Index Plasticity 20 5 mm 69 2 mm 62 1 mm 58 10 Percentage Passing Percentage 0.425 mm 46 0.250 mm 42 0 0.150 mm 39 0 10 20 30 40 50 60 70 80 90 100 0.075 mm 36 Liquid Limit Grading Modulus 1.56 Hydrometer Analysis SANS 3001 GR3 0.060 mm 36 Laboratory Number 1 2 0.040 mm 34 Atterberg Limits -425µ SANS 3001 GR10 0.020 mm 31 Liquid Limit % 51

0.006 mm 25 Plasticity Index % 20 Passing

Percentage Percentage 0.002 mm 19 Linear Shrinkage % 7.5 Gravel % 38 Overall PI % 9 Sand % 26 Classifications Silt % 17 HRB (AASHTO) A-7-5(2) Clay % 19 Unified (ASTM D2487) SM Note: An assumed S.G. may be used in Hydrometer Analysis calculations Weston Swell @ 1 kPa 100

40 1 20

Percentage Passing Percentage 0.001 0.01 0.1 1 10 100 Fine Medium Coarse Fine Medium Coarse Fine Medium Coarse Clay Silt Sand Gravel Client : CIVILAB (PTY) LTD - CENTURION Date Received: 06/06/2019 Project : Rehabilitation of Braamfontein West Water Management Unit Date Reported: 04/07/2019 Project No: 2019-B-840 Page No. : 7 of 5 MOISTURE DENSITY RELATIONSHIP Laboratory Number 1 Field Number TP5 Client Reference AFD Depth (m) 0.25-1.50 Position X Coordinates Y

Description

Additional Information Alberts Farm Calcrete / Crushed Stabilizing Agent Maximum Dry Density & Optimum Moisture Content - ASTM D698 Compactive Effort: Standard Proctor

Dry Density kg/m³ 1508 1546 1572 1543 1512 #N/A Moisture Content % 19 21 23 25 27 #N/A

Max. Dry Density kg/m³ 1572 Optimum Moisture % 22.9

Dry Density 1546 1572 1543 1508 1512 0% Air-Voids1580 at SG= 2.65 10% Air-Voids at SG= 2.65 1570

1560

1550

1540

1530 Dry Density Dry (kg/m³) 1520

1510

1500 18 19 20 21 22 23 24 25 26 27 28

Moisture Content (%) 36 Fourth Str.,Booysens Reserve,Johannesburg 2091 PO Box 82223,Southdale 2135 Civilab Tel:+27 (0)11 835 3117 Civil Engineering Testing Laboratory E-mail: [email protected] Website: www.civilab.co.za Direct Shear Test Results Project: REHABILITATION OF BRAAMFONTEIN WEST WATER MANAGEMENT UNIT Date Tested: 25/6/2019 Batch No.: 2019-B-840 Laboratory Number: 1 Field Sample Number: TP 5 (Alberts Farm) Depth (m): 0.25 - 1.50 Remark: A quick undrained test on a sample remoulded to approximately 90% Proctor.

Height Area Moisture Dry Unit Void Saturation Normal Peak Shear Content Weight Ratio Stress Stress Displacement mm mm2 % e % kPa kPa mm Initial 18.20 2851.04 22.4 1.39 1.102 59.6 Test 1 50.0 105.5 5.44 Final #REF! 22.2 #REF! #REF! #REF! Initial 18.20 2851.04 22.8 1.39 1.109 60.4 Test 2 105.0 180.8 5.64 Final #REF! 21.2 #REF! #REF! #REF! Initial 18.20 2851.04 23.1 1.39 1.114 60.9 Test 3 140.0 193.4 6.21 Final #REF! 21.0 #REF! #REF! #REF! Box Rate of shear (mm/min) Specific Gravity Internal Cohesion Type Test 1 Test 2 Test 3 Test 4 Friction (deg) (kPa) 2.932 ROUND 1.1732 1.2291 1.1373 #DIV/0! 45.3 60.5

250

200

150

100

50 Shear Stress (kPa) Stress Shear

0 0 50 100 150 Normal Stress (kPa)

Shear Stress 1 Shear Stress 2 Shear Stress 3 250

200

150

100

50 Shear Stress (kPa) Stress Shear 0 0 1 2 3 4 5 6 7 8 9 10 11 12 Displacement (mm)

Vertical Displacement 1 Vertical Displacement 2 Vertical Displacement 3 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8

Vertical Displacement (mm) Displacement Vertical -1 0 1 2 3 4 5 6 7 8 9 10 11 12 Displacement (mm)

Civilab (Proprietary) Limited. Registration No: 1998/019071/07 36/38 Fourth Street, Booysens Reserve, Johannesburg 2091 P O Box 82223, Southdale 2135 Civilab Tel: +27 (0)11 835-3117 • Fax: +27 (0)11 835-2503 E-mail: [email protected] • Website: www.civilab.co.za Civil Engineering Testing Laboratories Falling Head Permeability Test Results Project: REHABILITATION OF BRAAMFONTEIN WEST WATER MANAGEMENT UNIT Project No: 2019-B-840 Date: 04-Jul-19

Lab. Field Moisture Contents Dry density Kg/m3 Coefficient of Permeability (m/s) Depth (m) Sample Sample Before After As Range Initial Average Reference Reference Test (%) Test (%) tested Minimum Maximum TP 5 (Alberts 840-1 Farm) 0.25 - 1.50 22.3 27.0 1326 1461 1.0E-08 1.6E-08 1.2E-08

TP 2 (JVR Lower 840-2 Dam) 0.7 - 1.5 12.5 15.9 1694 1731 1.5E-07 2.0E-07 1.7E-07

TP 3 (JVR Lower 840-3 Dam) 0.2 - 0.5 14.3 18.1 1628 1679 1.5E-09 2.2E-09 1.8E-09

TP 3 (JVR Lower 840-4 Dam) 0.5 - 1.2 43.1 39.0 1170 1265 1.4E-10 2.4E-10 1.9E-10

TP 7 (JVR Lower 840-7 Dam) 0.5 - 1.7 19.2 22.0 1490 1531 1.7E-10 4.8E-10 2.7E-10

TP 2 (JVR Upper 840-9 Dam) 1.30 - 1.75 19.2 24.3 1653 1697 3.5E-09 4.5E-09 4.1E-09

TP 3 (JVR Upper 840-10 Dam) 0.0 - 1.0 16.6 23.6 1531 1578 1.0E-08 1.6E-08 1.3E-08

Remarks: Samples remoulded to approximately 90% Proctor. Saturated and tested under a load of 100kPa. Densities reported are under a load of 100kPa.

Civilab (Pty) Limited Registration No: 1998/019071/07 BRANCHES: CENTURION • JOHANNESBURG • RUSTENBURG

FallingHead-2019-B-840

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