GEOTECHNICAL INVESTIGATION FOR THE PROPOSED ALICEDALE RELIEF RISING MAIN

PREPARED BY:

ISSUED TO:

GIBB (PTY) LTD P.O. BOX 63703 Greenacres 6057

July 2016

Form 403.1 {'':lr'\r Stl'a| VERIFICATION PAGE Ce0tc.ltrl.!l & tin!lroDnrcntal Consultdtrts Rev 10/06

GEOTECHNICAL INVESTIGATION FOR THE PROPOSED ALICEDALE RELIED RISING MAIN

JOB NO:41650 DATE: Julv 2016 REPORT STATUS: FINAL REPORT

CARRIED OUT BY: COMMISSIONED BY: Terratest (Pty) Ltd Gibb (Pty) Ltd P.O. Box 27308 P.O, Box 63703 GREENACRES Greenacres 6057 6057

Tel: (041) 363 4428 Tel: (041) 392 7500 Fax: (041) 3631922 AUTHOR: CLIENT CONTACT PERSONS: Mr. L Parfitt Mr. J Barnard

SYNOPSIS: GEOTECHNICAL INVESTIGATION FOR THE PROPOSED ALICEDALE RELIEF RISING MAIN

KEY WORDS: Geotechnical,

@ COPYRIGHT: Terratest (Pty) Ltd.

QUALITY VERIFICATION

This report has been prepared under the controls established by a quality management system that meets the requirements of lSO9001: 2008 which has been independently certified by DEKRA Certification under certificate number 90906882

Verification Capacity Name Signature Date

By Author Geologist Mr L Parfitt July 2016 Checked by Snr Engineering Geologist Mr R Fyvie 4v July 2016 Authorised by Executive Associate Mr R Fyvie ry+ July 2016

GEOTECHNICAL INVESTIGATION FOR THE PROPOSED ALICEDALE RELIEF RISING MAIN

CONTENTS

1. INTRODUCTION ...... 4 2. TERMS OF REFERENCE ...... 6 3. DATA BASE ...... 6 4. SITE DESCRIPTION ...... 6 4.1. Topography ...... 6 4.2. Vegetation, Landuse and Infrastructure ...... 7 4.3. Access ...... 7 5. GEOLOGY AND GEOHYDROLOGY ...... 7 6. FIELD INVESTIGATION ...... 9 6.1. Trial Pits ...... 9 6.2. Laboratory Testing ...... 10 7. GROUNDWATER ...... 10 8. LABORATORY RESULTS ...... 10 9. GENERAL STABILITY OF THE SITE ...... 12 10. PIPELINE GEOTECHNICAL APPRAISAL ...... 12 10.1. Material Specifications ...... 12 10.2. Design Specifications...... 13 10.3. Excavation Conditions ...... 13 10.4. Problem Areas ...... 14 10.5. Flooding and Erosion ...... 15 10.6. Usability of Materials ...... 16 10.7. Construction Materials ...... 17 11. DEVELOPMENT RECOMMENDATIONS ...... 17 11.1. Pumpstation ...... 17 12. CONCLUSION ...... 19 13. REFERENCES ...... 20

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LIST OF TABLES AND FIGURES Figure 1: Locality Plan ...... 5 Figure 2: Geological Map ...... 8 Table 6.1: Trial Pit coordinates ...... 9 Table 8.1: Atterberg Limit Determination Test Results ...... 11 Table 8.2: MOD/CBR Relationship ...... 11 Table 10.1: Excavation class descriptions ...... 13 Table 10.2: Estimated excavation classes ...... 14 Table 10.3: Sources of Selected Fill Material ...... 16

APPENDICES

APPENDIX A: TRIAL PIT PROFILES AND PHOTOGRAPHIC PLATES APPENDIX B: LABORATORY TEST RESULTS

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1. INTRODUCTION

This report presents the results of a geotechnical investigation undertaken for the proposed Relief Rising Main in Alicedale, as depicted in Figure 1: Locality Plan. The investigation spanned from the westernmost boundary of Alicedale, along the railway line, up to and including the north-westernmost section of Kwanonzwakazi Informal Settlement in the east.

The objectives of the investigation comprised an assessment of the surface and subsurface geotechnical characteristics, in respect of the following:

• The identification and analysis of potentially adverse conditions, including problem and substrata and areas of high water table; • Ease of excavation to the proposed pipeline trench invert level; • The usability of the excavated trench materials for construction purposes; • Any other factors that, from a geological or geotechnical context, could impact on the construction of the project.

The fieldwork for the investigation was undertaken on June 30 th 2016. All trial pits were profiled by a Terratest Geologist in accordance with methods outlined by Jennings et al. (1973). The and rock conditions beneath the site are described and comment is made on the general suitability of the site for development. Recommendations for , drainage, ease of excavation, and design are provided. The information in this report is given in good faith as an indication of materials and conditions likely to be encountered during construction. Any opinions and interpretations expressed are given as a guide only. There is no warranty that the information is totally representative of the whole area and no responsibility will be accepted for any consequences arising from actual conditions being different from those indicated in this document.

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Figure 1: Locality Plan

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2. TERMS OF REFERENCE

Terratest (Pty) Ltd were invited by Gibb (Pty) Ltd to prepare a proposal and cost estimate to conduct a geotechnical investigation for the proposed Relief Rising Main. A quotation dated 26 April 2016, referenced 3113/93/002/LW/lw, was submitted and the notification of acceptance was received via email on 16 May 2016.

3. DATA BASE

The following information was provided by Gibb :

• KMZ GoogleEarth file indicating the position of proposed trial pits. • PDF locality plan indicating the proposed trial pit positions, as as the proposed pipeline alignment. • Plans, including longitudinal sections for both Option 1 and Option 2.

The trial pit positions were shown to Terratest’s Geologists by Gibb’s Mr Jacques Barnard during a site walkover on June 30 th 2016.

4. SITE DESCRIPTION

The investigation site is located in Alicedale, in the interior region of the Eastern Cape, figure 1. Alicedale is located approximately 30km from Paterson, using the National Route 10 and the subsequent MR476. The investigation site covers the town of Alicedale for the most part and incorporates the north-westernmost section of Kwanonzwakazi Informal Settlement. The Bushmans River runs just north of the town, with its associated drainage features contributing to the variable topography.

4.1. Topography Elevations across the investigation area range from approximately 282 meters above mean sea level (mamsl) at the westernmost point (ATP08), to approximately 305 mamsl at the easternmost point (ATP06). The topography of the area is generally flat to undulating, owing to the proximity of the Bushmans River and previous periods of regional tectonic uplift.

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4.2. Vegetation, Landuse and Infrastructure The natural vegetation covering investigation area is Albany Broken Veld, comprised of grassy dwarf shrubland, scattered low trees and grasses.

Existing infrastructure that was encountered included surfaced , formal residential housing, railway infrastructure, overhead power lines as well as underground services. Prior to construction the various service providers must be contacted and notified of the work, so that the correct wayleaves can be received. The presence of existing underground services was taken into account when positioning the trial pits.

4.3. Access Alicedale was accessed by travelling along the N10 between Paterson and Cookhouse for approximately 11km and then subsequently turning right on to the MR476 and travelling approximately 16km. Access to the trial pits is adequate, as they are sited in open areas adjacent to roads, figure 1. Access to position ATP07 requires crossing the railway line on the western side of the town.

5. GEOLOGY AND GEOHYDROLOGY

According to the 1:250 000 geological map (3326 GRAHAMSTOWN) published by the Council for Geoscience, the investigation area is underlain by light grey, medium-grained, quartzitic sandstones and minor greyish-black micaceous mudrock of the Witpoort Formation of the Witteberg Group. In some localities the Witpoort Formation is overlain by the Lake Mentz Subgroup, comprised of mudrock, quartzitic sandstone and feldspathic sandstone. Typically within the area, the Witpoort Formation is overlain by Quaternary aged alluvial deposits.

The local and regional geology of the investigation area is presented in Figure 2.

According to the 1:500 000 hydrogeological map (3324 PORT ELIZABETH) published by the Department of Water Affairs and Forestry , the investigation area has historically received a mean annual precipitation of 400 – 600mm, with in the area potentially yielding 0.5 - 2.0 litres/second.

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According to the 1:6 000 000 Map of Southern Africa, the site falls within a level five area on the Modified Mercalli Scale (MMS). Peak horizontal ground acceleration of 0 - 50cm/s 2 has been recorded, with a 10% probability of this being exceeded at least once in a 50 year period.

Figure 2: Geological Map

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6. FIELD INVESTIGATION

The field investigation entailed: (i) The machine-excavation of eight (8) trial pits at pre-determined positions; (ii) The retrieval of selected subsoil samples for laboratory analyses; and

6.1. Trial Pits The subsurface conditions were assessed in a total of eight (8) trial pits excavated across the study area, by means of a Tractor-Loader-Backhoe (TLB) to depths between 1.90 and 3.10 m. Trial pits were labelled ATP01 through ATP08.

Fill, alluvial, residual and rock material was intersected across the investigation site. The fill material comprises; sandy , gravelly sandy SILT and gravelly silty with builder’s rubble and refuse. The Alluvial material is dominated by gravelly sandy SILT, silty SAND, and and cobbles. The residual material encountered at ATP06 was comprised of gravelly SILT. Shale of the Lake Mentz Subgroup was intersected at ATP06. Near refusal was encountered at trial pits ATP05 (gravel and cobbles), ATP06 (shale), ATP07 (silty sand), ATP08 (sandy silt).

The positions of the trial pits are indicated on the locality plan presented in Figure 1. A list of the trial pit coordinates is provided in Table 6.1. The trial pits were profiled according to the method and terminology of Jennings et al (1973). The trial pit profiles and photographic plates are presented in Appendix A.

Table 6.1: Trial Pit coordinates

Trial Pit Latitude Longitude ATP01 33°19'04.20"S 26° 04'50.00"E ATP02 33°19'04.40"S 26° 04'59.60"E ATP03 33°18'58.00"S 26° 05'01.60"E ATP04 33°18'58.80"S 26° 05'09.90"E ATP05 33°18'59.70"S 26° 05'23.10"E ATP06 33°19'04.10"S 26° 05'36.50"E ATP07 33°19'02.20"S 26° 04'46.00"E ATP08 33°18'58.20"S 26° 04'45.30"E

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6.2. Laboratory Testing The following laboratory tests were carried out on disturbed samples recovered during the investigation:

• Foundation Indicator tests (x8) • Modified AASHTO (American Association of State Highway and Transport Officials) and (CBR) tests (x8)

The results of the laboratory testing are summarized in Section 8 and the full test results are contained in Appendix B.

7. GROUNDWATER

No water seepage was noted during the excavation of trial pits. The potential for perched water table conditions to develop, particularly following heavy and/ or prolonged periods of precipitation, should not be discounted given the variable topography and lowered permeability due to the high fines content of the subsoil profile.

8. LABORATORY RESULTS

Representative samples of the materials intersected in the trial pits and boreholes were retrieved for laboratory testing, for the purposes of assessing:

• The use of materials excavated from the pipeline trench as bedding and selected backfill; and • The presence of materials possessing deleterious properties;

The testing undertaken included Foundation Indicator, Modified AASHTO and CBR tests. The results of the testing are summarized in Tables 8.1 and 8.2 and are presented in Appendix B.

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Table 8.1: Atterberg Limit Determination Test Results

Atterberg Soil Mortar Analysis (%) Limits (%) Sample Trial Pit Potential Depth (m) Description Coarse Medium Fine Passing GM No. No. Coarse Expansion Fine Fine Fine 0.075 LL PI LS Sand sand Sand Sand mm ATP 01 A ATP 01 0.65 - 3.00 Silt 1.0 9.0 23.0 22.0 44.0 22 4 2.0 0.6 LOW ATP 02 A ATP 02 0.24 - 3.05 Silt 5.0 16.0 31.0 22.0 27.0 15 0 0.1 0.79 LOW ATP 03 A ATP 03 0.26 - 3.05 Silt 1.0 8.0 24.0 25.0 42.0 15 3 1.5 0.62 LOW ATP 04 A ATP 04 0.10 - 3.10 Silt 7.0 15.0 26.0 22.0 30.0 16 0 0.1 0.77 LOW Gravel and ATP 05 B ATP 05 0.05 - 1.90 19.0 10.0 7.0 5.0 60.0 34 19 9.5 2.16 LOW Cobbles ATP 05 A ATP 06 0.75 - 2.02 Shale 16.0 25.0 18.0 11.0 30.0 23 9 3.5 1.4 LOW ATP 07 A ATP 07 0.27 - 2.10 Sand 5.0 2.0 8.0 21.0 63.0 22 9 4.5 0.65 LOW ATP 08 A ATP 08 0.40 - 1.94 Silt 3.0 1.0 8.0 23.0 65.0 19 7 3.5 0.56 LOW LL - Liquid Limit GM - Modulus LS - Linear Shrinkage PI - Plasticity Index

Sediments <0.075 mm in diameter generally form the bulk components of the material sampled on site, between 27 and 65%. The sampled material had Plasticity Index (PI) values of 0 to 19% while Linear Shrinkage (LS) values ranged between 0.1 – 9.5 %. The sample from ATP05 exhibits a LS value of 9.5 and is considered problematic for moisture-related heave and shrinkage. The soil parameters, of the remaining samples, suggest a low potential for expansion and moisture-related shrinkage, respectively.

Table 8.2: MOD/CBR Relationship

CBR Maximum Sample Trial Pit MDD Swell TRH 14 Depth (m) Description OMC % No. No. kg/m 3 MAASHTO Classification 90% 93% 95% 98% 100% % ATP 01 A ATP 01 0.65 - 3.00 Silt 2104 8.3 8 9 9 10 10 0.6 G10 ATP 02 A ATP 02 0.24 - 3.05 Silt 2101 7.2 4 7 9 11 12 0.1 G10 ATP 03 A ATP 03 0.26 - 3.05 Silt 2081 8.5 2 4 7 20 47 0.1 G10 ATP 04 A ATP 04 0.10 - 3.10 Silt 2095 7.2 2 5 9 12 13 0.7 G10 Gravel and ATP 05 B ATP 05 0.05 - 1.90 2134 8 7 12 17 29 42 1.4 G10 Cobbles ATP 05 A ATP 06 0.75 - 2.02 Shale 2107 9.5 4 6 7 12 17 1.4 G10 ATP 07 A ATP 07 0.27 - 2.10 Sand 1974 9.8 7 7 7 8 8 0.2 G10 ATP 08 A ATP 08 0.40 - 1.94 Silt 2006 9.5 6 7 9 15 22 0.1 G10

The results from the MOD/ CBR tests are fairly conclusive in their representation of in situ materials sampled from the investigation site. The classification of materials (G10) reflects the composition and strengths of the in situ soil. These materials are of very poor quality and are not suitable for use in or structural applications, and should be spoiled. All material classifications were assessed in accordance with TRH 14 (1985).

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9. GENERAL STABILITY OF THE SITE No signs of inherent ground instability such as tension cracks, slip scars or sloughing of the soil mantle were evident during the visual inspection across the site. The topography across the investigation site is generally level to undulating.

10. PIPELINE GEOTECHNICAL APPRAISAL

10.1. Material Specifications In terms of the SANS 1200 LB (1983) concerning bedding requirements, buried pipelines may require two types of selected material. These selected materials are termed "Selected Granular Material", "Selected Fill Material" and “General Backfill”.

4.1.1. Selected Granular Material – Bedding Cradle

The bedding cradle is the zone that is placed beneath the pipe and extends up the sides to a specified thickness according to the class of bedding and must comprise a selected granular material. Selected granular material comprises granular, non-cohesive material that is singularly graded between 0.6mm and 19mm, is free draining and has a compactibility factor not exceeding 0.4, or other values specified under the project specifications.

4.1.2. Selected Fill Material The selected fill blanket is the material extending from above the bedding, which is placed and compacted around and to a specified thickness above the pipe. This material shall have a plasticity index (PI) not exceeding 6, a maximum particle size not exceeding 30mm, and be free of vegetation.

4.1.3. General Backfill This material, also known as ‘Main Fill” is approved filling material placed in the pipe trench on top of the Selected Fill Material, up to ground level, and normally consists of material originally removed from the trench for the pipe excavation. It has no specific stipulations in respect of material quality, other than that it must be free of excessively large boulders.

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10.2. Design Specifications. The invert levels at trial pit positions, as indicated on drawings provided, vary across the investigation site from 1.00m to 4.05m.

10.3. Excavation Conditions Excavation profiles are attached in Appendix A. The ease of excavation along the pipeline route has been assessed according to the criteria published in SANS 1200D Earthworks, as specified for restricted excavation. Descriptions of the excavation classes are given in Table 10.1. The percentages estimated for each class of excavation are based on the average vertical expression of material in each trial pit.

Table 10.1: Excavation class descriptions

Excavation Class Description Soft Excavation in material that can be efficiently removed by a back- acting excavator of flywheel power approximately 0.10 kW per millimetre of tined-bucket width, without the use of pneumatic tools such as paving breakers Intermediate Excavation in material that requires a back-acting excavator of flywheel power exceeding 0.10 kW per millimetre of tined-bucket width or the use of pneumatic tools before removal by equipment equivalent to that specified for soft excavation. Hard Hard rock excavation shall be excavation in material (excluding boulder excavation) that cannot be efficiently removed without blasting or wedging and splitting.

The overall estimated classes of excavation are calculated, per trial pit, below in Table 10.2. The extrapolation of information between test positions must be done with caution owing to the significant distances between trial pits.

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Table 10.2: Estimated excavation classes

Trial Pit / Excavation Invert Level (m), as Excavation Classes Depth (m) per option 1 Soft (%) Intermediate (%) ATP01 3.00 4.05 74 26* ATP02 3.05 3.30 100* - ATP03 3.05 4.04 76 24* ATP04 3.10 1.74 100 - ATP05 1.90 1.50 100 - ATP06 2.02 1.50 50 50 ATP07 2.10 1.22 100 - ATP08 1.94 1.00 100 -

Soft excavation is expected across most of the investigation site where trial pits where excavated. Intermediate excavation conditions are expected in the vicinity of ATP01 and ATP03 where trail pits were terminated in medium dense gravelly material and, ATP06 where shale was intersected.

*Excavation classes are inferred where invert levels are deeper than trial pit termination depths.

10.4. Problem Areas Various general problems are associated with the lithologies found on site, and it is recommended that these be borne in mind during construction.

10.4.1. Shallow Groundwater Conditions

The pipeline falls within an area where the subsoil profile is dominated by material containing a high proportion of fines, the formation of a perched water table may occur during periods of heavy rainfall and measures should be taken to manage stormwater during construction. Provision must be made for dewatering measures and sidewall stabilisation when needed.

10.4.2. Trench Instability

The provisions of the Occupational Health and Safety Act of 1993 and Construction Regulations of 2014 must be followed in the excavations and workings therein. In terms of Section 11 of the Construction Regulations the contractor must appoint an excavation supervisor.

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Sidewall collapse may be a risk during the construction of the pipeline, where shoring measures must be considered to prevent trench collapse.

Instability problems may be particularly problematic where the following ground conditions are encountered.

• Very loose to loose fill and alluvial material. • Moist to wet, silt material. These conditions are expected to prevail over large sections of the pipeline route.

10.4.3. Quality of Trench Materials

From a visual assessment and the laboratory results, a large proportion of the soils encountered along the pipeline route meet the requirements specified in SABS 1200 LB (1983) for use as selected material for pipeline construction.

The usability of the trench materials is further discussed in Section 10.6.

10.4.4. Close Proximity to Existing Underground Infrastructure

The proposed pipeline will be constructed in very close proximity to existing pipelines and other services. This may be problematic during construction, particularly where trench instability will be encountered, as the proximity of the nearby pipelines will prevent battering back of the trench sidewalls to a stable angle.

Potential loss of support to the adjacent pipelines during trenching must be taken into account during construction planning.

10.5. Flooding and Erosion Protective measures against flooding and erosion must be implemented adjacent to all water courses and drainage lines.

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10.6. Usability of Trench Materials As the design drawings for the pipeline are not available the pipeline bedding class specified in SANS1200 LB is unknown. Comment on the existing material’s suitability for potential applications is, however, provided below.

10.6.1. Selected Granular Material Based upon observations during the trial pit investigation and laboratory test results, the materials derived from the trench excavation do not comply with the specification for Selected Granular Material. Material observed and tested all contain particle size fractions of <0.6 mm, thereby excluding them. It is recommended that Selected Granular Material be acquired from commercial sources.

10.6.2. Selected Fill Material Based on the results from lab testing, a portion of the soils found on site meet the requirements for Selected Fill Material. The location of the trench materials that meet the requirements as Selected Fill Material are shown in Table 10.2, and may be used as such. The sources of Selected Fill Material, across the site, should be sufficient for the pipeline installation; alternatively Selected Fill Material may be acquired from commercial sources.

Table 10.3: Sources of Selected Fill Material

Trial Pit / Borehole Depth (m) ATP01 0.65 – 3.00 ATP02 0.24 – 3.05 ATP03 0.26 – 3.05 ATP04 0.10 – 3.10

10.6.3. General Backfill Lab results and field observations during the trial pit investigation show that General Backfill may comprise material originally excavated from the pipeline trench, with the exclusion of rock fill in excess of 150 mm in size.

It is recommended that the top of the fill overlaps the sides of the trench by 150 mm on either side and be domed to a centre height of 150 mm above the top of the trench.

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10.7. Construction Materials The recommended sources of construction materials are as follows:

Selected Granular Material: Commercial sources Selected Fill Material: Trench excavations/Commercial Sources General Backfill: Trench excavations

11. DEVELOPMENT RECOMMENDATIONS

11.1. Pumpstation

Trial pit ATP01 was excavated at the proposed pumpstation site. The soil profile is dominated by sandy silt with; gravel, cobbles and boulders in places. Dynamic Cone Penetrometer (DCP) testing was not requested for this investigation, therefore no estimated bearing pressures can be given.

11.1.1. Earthworks and Ease of Excavation

The trial pit was excavated to the intended termination depth of 3.00.

The Excavation for the proposed pumpstation development is therefore expected to utilise soft excavation techniques for the removal of soils. According to the SANS 1200D classes of excavation specification, soft excavation techniques are used for material that can be efficiently removed or loaded by any of the following plant without prior ripping: • Bulldozer: mass of approximately 22 tons (including mass of ripper) and an engine developing approximately 145 KW at the flywheel; • Tractor scraper: mass of approximately 28 tons and an engine developing approximately 245 KW at the flywheel, pushed by a bulldozer (as above) during loading; • Tract-type front end loader: mass of approximately 22 tons and an engine developing approximately 145 KW at the flywheel.

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11.1.2. Foundation Recommendations

A review of the trial pit profile and laboratory test results indicate that subsoil conditions are not favourable for founding purposes. Moisture Density Relationship and California Bearing Ratio tests indicate that sample ATP01A is of very poor quality with a TRH14 classification of G10. The material is not suitable for use in fill, road or structural applications, and should be spoiled. The trial pit excavation also indicated that the soil intersected was in a dry state, the introduction of water reduces the of the soil resulting in a lower .

Taking these factors in to account an adapted foundation design utilising an engineered soil raft is recommended. Fill material must be removed from the structural footprint of the pumpstation site, which must then be over-excavated and the in-situ material at the base be suitably compacted. The over-excavated material must then be replaced with an engineered soil raft of a minimum of 1.5B (where B = the foundation width) thickness below the footing founding level to reduce the risk of differential settlement of the structures, upon which the footings may be placed. It is recommended that this improved soil raft be comprised of an inert G7 material or better, imported and compacted in <200 mm increments to a minimum of 95% Mod. AASHTO density at Optimum Moisture Content until the desired base level is reached.

An important element in the promotion of a stable site is the control and removal of surface water and groundwater from the site. The layers below the constructed foundation must be kept at a stable moisture content to reduce the risk of soil settlement. Surface water run-off water must be directed away from the structures so that it does not pond adjacent to the foundations.

Vegetation that requires watering must not be planted adjacent to the structure, including large trees or shrubs that would locally affect the moisture regime.

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It is recommended that an experienced and competent geotechnical engineer be appointed to inspect the earthworks and foundation excavations during the development of the site to confirm founding depths, bearing pressures and validate the recommendations provided in this report.

12. CONCLUSION

The foregoing report presents the results of a geotechnical investigation for the proposed Alicedale Relief Rising Main.

A number of design and precautionary recommendations have been made in Sections 9, 10 and 11 of the report. These include:

• The overall estimated classes of excavation (as per SANS 1200D Earthworks), per trial pit, are given in Table 10.2 above.

• Support and stabilisation of the trench sidewalls must form part of the construction provisions, in areas exhibiting very loose to loose fill and alluvial material and very moist to wet, silty soils. The must be inspected by a qualified excavation inspector prior to any persons entering the trench.

• Selected Granular Material is not available on site and should obtained from commercial sources.

• Trench materials, in the vicinity of trial pits ATP01 through ATP04, meet the requirements for Selected Fill Material (as per SABS 1200 LB) and may be used as such, these areas, along with depths, are listed in Table 10.3.

• All trench materials are suitable for use as General Backfill with the exception rock fill in excess of 150 mm in size.

The extent of the investigations undertaken is deemed adequate, within the time and budget constraints, to present an overview of the geotechnical conditions across the investigation site. Further foundation specific testing is recommended to be conducted at the remaining pumpstation site.

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It must be borne in mind that the overall interpretation of geotechnical conditions is based upon point information derived from the respective test positions and that conditions intermediate to these have been inferred by interpolation, extrapolation and professional judgement.

13. REFERENCES

• Craig. R.F. (2004). Craig’s . 7th Edition. London: Spon Press.

• Department of Water Affairs and Forestry (1998). 1:500 000 Hydrogeological Map Series (3324 Port Elizabeth) of the Republic of South Africa , 1st Edition. Associated Printing, Cape Town.

• Geological Survey (1991). 1:250 000 Geological Map Series 3326 Grahamstown . Government Printer, Pretoria.

• Geological Survey (1992). 1:6 000 000 Seismic Hazard Map for Southern Africa. Government printer, Pretoria.

• Geological Survey (2000). 1:50 000 Geological Map Series 3326AC Alicedale . Government Printer, Pretoria.

• Jennings J.E, Brink, A.B.A. and Williams A.B. Revised Guide to Soil Profiling for Civil Engineering Purposes in Southern Africa . The Civil engineer in South Africa, January (1973).

• Johnson, M.R. and Le Roux, F.G. (1994). The Geology of the Grahamstown Area. Council for Geoscience

• Proceedings of the Symposium on Exploration for Rock Engineering (1976). A Guide to Core Logging for Rock Engineering. Core Logging Committee of the South Africa Section of The Association of Engineering Geologists.

• SANS 1200 D. Standardised Specification for Civil Engineering Construction, Section D: Earthworks . South African National Standards, (1988).

• TRH 14, (1985). Guidelines for Road Construction Materials. Government Printers, Pretoria.

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• www.GoogleEarth.com

APPENDICES

APPENDIX A: TRIAL PIT PROFILES AND PHOTOGRAPHIC PLATES

APPENDIX B: LABORATORY TEST RESULTS

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APPENDIX A

TRIAL PIT PROFILES AND PHOTOGRAPHIC PLATES

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JULY 2016 GIBB (PTY) LTD. HOLE No: ATP 01 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, grey-brown, loose, intact, sandy SILT with rootlets: Fill. 0.10 Dry, grey mottled white, loose to medium dense, intact, gravelly, sandy SILT with refuse: Fill. 0.65 Dry, reddish yellow-brown, loose to medium dense, intact, sandy SILT with occasional cobbles and boulders of quartzitic sandstone: Alluvial. ATP01A

3.00

NOTES

1) No refusal.

2) No water table encountered.

3) Sample taken from ATP01A 0.65--3.00m.

4) Photo.

5) Ease of Excavation: Soft.

6) Duration of Excavation: 15 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d19’04.2’’S DRILLED BY : DATE : Y-COORD : 26d04’50.0’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 01 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 02 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, grey-brown, loose, intact, silty, fine grained SAND with rootlets: Alluvial. 0.24 Dry, yellowish brown, medium dense, intact, sandy SILT with minor rootlets: Alluvial.

ATP02A

3.05

NOTES

1) No refusal.

2) No water table encountered.

3) Sample taken from ATP02A 0.24--3.05m.

4) Photo.

5) Ease of Excavation: Soft to medium.

6) Duration of Excavation: 15 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d19’04.4’’S DRILLED BY : DATE : Y-COORD : 26d04’59.6’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 02 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 03 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, grey-brown, very loose to loose, intact, silty, fine grained SAND with rootlets and minor gravel: Alluvial. 0.26 Dry, yellowish brown, medium dense, intact, slightly gravelly, sandy SILT with minor rootlets: Alluvial.

ATP03A

3.05

NOTES

1) No refusal.

2) No water table encountered.

3) Sample taken from ATP03A 0.26--3.05m.

4) Photo.

5) Ease of Excavation: Soft to medium.

6) Duration of Excavation: 20 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d18’58.0’’S DRILLED BY : DATE : Y-COORD : 26d05’01.6’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 03 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 04 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, grey-brown, loose, intact, silty SAND with abundant rootlets: Alluvial. 0.10 Dry, yellowish brown, medium dense to dense, intact, sandy SILT with minor rootlets: Alluvial.

ATP04A

3.10

NOTES

1) No refusal.

2) No water table encountered.

3) Sample taken from ATP04A 0.10--3.10m.

4) Photo.

5) Ease of Excavation: Soft to medium.

6) Duration of Excavation: 10 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d18’58.8’’S DRILLED BY : DATE : Y-COORD : 26d05’09.9’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 04 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 05 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, greyish brown, loose, intact, gravelly, sandy SILT with rootlets: Alluvial. 0.05

ATP05B Dry, reddish brown, loose to dense, intact, GRAVEL and COBBLES of quartzitic sandstone with silty sand, minor boulders and rootlets: Alluvial.

1.90

NOTES

1) Near-refusal on dense material.

2) No water table encountered.

3) Sample taken from ATP05B 0.05--1.90m.

4) Photo.

5) Ease of Excavation: Medium to hard.

6) Duration of Excavation: 20 Min.

7) Power cable noted at 0.85m, excavation position shifted.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d18’59.7’’S DRILLED BY : DATE : Y-COORD : 26d05’23.1’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 05 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 06 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, reddish brown, loose, intact, silty SAND with cobbles and boulders of quartzitic sandstone and rootlets: Alluvial. 0.46 Dry, yellowish dark brown, medium dense, intact, gravelly SILT: Residual. 0.75

ATP05A Grey-brown stained black, highly weathered, fine grained, weakly bedded, soft to medium hard rock, fractured SHALE: Lake Mentz Subgroup.

2.02

NOTES

1) Near-refusal on shale.

2) No water table encountered.

3) Sample taken from ATP05A 0.75--2.02m.

4) Photo.

5) Ease of Excavation: Soft to hard.

6) Duration of Excavation: 15 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d19’04.1’’S DRILLED BY : DATE : Y-COORD : 26d05’36.5’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 06 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 07 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, grey-brown, very loose to loose, intact, sandy SILT with rootlets: Fill. 0.05 Dry, grey-brown mottled white, loose, intact, gravelly, sandy SILT with builders rubble: Fill. 0.27 ATP07A Dry, red-brown, medium dense to dense, intact, silty, fine grained SAND with minor rootlets: Alluvial.

2.10

NOTES

1) Near-refusal on dense material.

2) No water table encountered.

3) Sample taken from ATP07A 0.27--2.10m.

4) Photo.

5) Ease of Excavation: Medium.

6) Duration of Excavation: 20 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d19’02.2’’S DRILLED BY : DATE : Y-COORD : 26d04’46.0’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 07 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67 GIBB (PTY) LTD. HOLE No: ATP 08 ALICEDALE RELIEF RISING MAIN, Sheet 1 of 1 GEOTECHNICAL INVESTIGATION JOB NUMBER: 41650

Scale 0.00 1:50 Dry, grey-brown, very loose to loose, sandy SILT with rootlets: Fill. 0.15 Dry, grey-brown mottled white, loose, intact, gravelly, silty fine grained SAND with builders rubble: Fill. 0.40 ATP08A Dry, reddish yellow-brown, medium dense to dense, intact, sandy SILT: Alluvial.

1.94

NOTES

1) Near-refusal on dense material.

2) No water table encountered.

3) Sample taken from ATP08A 0.40--1.94m.

4) Photo.

5) Ease of Excavation: Medium.

6) Duration of Excavation: 15 Min.

CONTRACTOR : INCLINATION : ELEVATION : MACHINE : DIAM : X-COORD : 33d18’58.2’’S DRILLED BY : DATE : Y-COORD : 26d04’45.3’’E PROFILED BY : L PARFITT/L WHITECROSS DATE : 30/05/2016 HOLE No: ATP 08 TYPE SET BY : M RICHARDS DATE : 04/07/2016 14:19 SETUP FILE : TP-TT-A4.SET TEXT : ..\DOTS\41650ATP01TP08.TXT D028 JG Afrika (Pty) Ltd dotPLOT 7016 PBp67

PLATES 1 & 2: Trial pit ATP01 profile ( left), and trial pit ATP02 profile (right ).

PLATES 3 & 4: Trial pit ATP03 profile ( left), and trial pit ATP04 profile (right ).

P:\01 TERRATEST\41650 - Alicedale Relief Rising Main Geotech\07 REPORTS\Appendix A - Trial Pit Photographic Plates.docx

July 2016

ATP06

PLATES 5 & 6: Trial pit ATP05 profile ( left), and trial pit ATP06 profile (right ).

ATP07

PLATES 7 & 8: Trial pit ATP07 profile ( left), and trial pit ATP08 profile (right ).

P:\01 TERRATEST\41650 - Alicedale Relief Rising Main Geotech\07 REPORTS\Appendix A - Trial Pit Photographic Plates.docx

July 2016

23

APPENDIX B

LABORATORY TEST RESULTS

P:\01 TERRATEST\41650 - Alicedale Relief Rising Main Geotech\07 REPORTS\Geotechnical Investigation Report.docx

JULY 2016