Vgi7148 S19 Pipeline Realignment Typset For Mail.pdf

PIPELINE REALIGNMENT, BLUEBELL STREET, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION VGI7148 S19

Compiled by: VGIconsult Projects P.O. BOX 604 FOURWAYS 2055 TEL : (011) 469 0854 FAX : (011) 469 0961 FAX : 0866892847 e-mail: [email protected]

Consulting Engineering Geologists & Engineers

VGIconsult VGIconsult Projects (Pty.) Ltd. Registration number 2003/015042/07

MORAD CONSULTING PTY LTD 274 VOORTREKKER ROAD NOORDHEUWEL MOGALE 1740

P.O. Box 604 Fourways 2055 Gauteng Telephone Direct : (011) 469 0854 Fax : (011) 469 0961 Fax : 0866892847 E-mail [email protected]

ATTENTION: MR NORMAN DUMA

Your reference

Our reference

Date

VGI7148 S19

23 JUNE 2017

PIPELINE REALIGNMENT, BLUEBELL STREET, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION SUMMARY This report presents the results of a dolomite stability investigation carried out along the proposed pipeline route in Bluebell Street, Carletonville, which will realign a section of the existing water pipeline which has been affected by a sinkhole. The boreholes intercept chert and dolomite residuum of variable thickness. Cavernous conditions, including disseminated voids, are intercepted in some of the boreholes. Weathered dolomite bedrock/hard rock dolomite is intercepted atvariable depths (0m to 48m). All the boreholes were recorded as “dry” 24 hours after drilling. The groundwater level is anticipated at 200m depth, whilst the OWL is at 1469m AMSL or 81m deep. The pipeline alignment is characterised by two dolomite hazard areas as follows: Dolomite Hazard Zone

Hazard Classification

1

4/7//1

2

5/6(3)//1

Description Area largely reflecting a medium to high susceptibility of large-size sinkhole and subsidence formation with respect to ingress of water and a low susceptibility of all-size sinkhole and subsidence formation with respect anthropogenic groundwater level drawdown. Area largely reflecting a high susceptibility of small- to mediumsize sinkhole and subsidence formation (sub-areas may comprise a medium susceptibility of medium-size sinkholes and subsidences) with respect to ingress of water and a low susceptibility of all-size sinkhole and subsidence formation with respect anthropogenic groundwater level drawdown.

The report presents precautionary measures as well as recommendations in terms of improvement of the sub-surface soils around boreholes which intercepted problematic conditions, monitoring activities to minimise the risk of sinkhole occurrence in future.

Directors: D.B. Buttrick Ph. D. (Eng. Geol.), MSAIEG, Pr. Sci. Nat. ; A.A. Gerber B. Eng., Pr. Eng. ASB: N.Y.G. Trollip M. Sc. (Eng. &Env.), Pr. Sci. Nat., AMSAIEG ; I. Kleinhans M. Sc. (Eng. &Env.), Pr. Sci. Nat.

PIPELINE REALIGNMENT, BLUEBELL STREET, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION SUMMARY TABLE OF CONTENTS 1. 2. 3.

4. 5.

6.

7.

8.

9.

10.

Preface PAGE NUMBER

INTRODUCTION ................................................................................................................... 1 TERMS OF REFERENCE ..................................................................................................... 1 AVAILABLE INFORMATION ................................................................................................ 1 3.1. Topographic Data....................................................................................................... 1 3.2. Geological Information ............................................................................................... 1 3.3. Industry Standards ..................................................................................................... 1 3.4. Geohydrological Information ...................................................................................... 2 DESCRIPTION OF THE STUDY AREA ................................................................................ 2 PROCEDURES USED IN THIS STUDY ................................................................................ 2 5.1. Assimilation of Available Data .................................................................................... 2 5.2. Map Production (Projection, Co-ordinate System and Datum).................................... 3 5.3. Geophysics (Gravity Method) ..................................................................................... 3 5.4. Rotary Percussion Boreholes ..................................................................................... 3 5.5. Hazard Characterisation Procedure ........................................................................... 4 5.6. Monitoring Designations ............................................................................................. 8 GEOLOGY AND GEOHYDROLOGY ...................................................................................10 6.1. General Geology .......................................................................................................10 6.2. Local Geology ...........................................................................................................11 6.3. Geohydrology............................................................................................................12 6.4. Background: July 2016 Sinkhole ...............................................................................12 DOLOMITE HAZARD CHARACTERISATION .....................................................................13 7.1. Site investigation and Dolomite Hazard Assessment Procedures ..............................13 7.2. Dolomite Hazard Zone 1 (Hazard Class 4/7//1) .........................................................13 7.3. Dolomite Hazard Zone 2 (Hazard Class 5/6(3)//1) .....................................................15 CONCLUSIONS ...................................................................................................................17 8.1. Results of the Drilling Programme .............................................................................17 8.2. Dolomite Hazard Characterisation .............................................................................17 RECOMMENDATIONS ........................................................................................................18 9.1. Improvement of subsoil conditions ............................................................................18 9.2. Precautionary Measures ...........................................................................................19 9.3. Open works and general construction activities .........................................................19 9.4. Stormwater Management ..........................................................................................19 9.5. Monitoring Actions.....................................................................................................20 9.6. Database of Ground Movement and Stability Conditions ...........................................20 GENERAL ............................................................................................................................20

TABLES SUMMARISED BOREHOLE INFORMATION AND INHERENT HAZARD CHARACTERISATION

TABLE 1

FIGURES LOCALITY PLAN TOPOGRAPHICAL SHEET LEGEND SITE LAYOUT WITH GROUND ELEVATION CONTOURS REGIONAL GEOLOGY GEOLOGY LEGEND REGIONAL GEOHYDROLOGY

FIGURE 1 FIGURE 1A FIGURE 2 FIGURE 3 FIGURE 3A FIGURE 4

DRAWINGS RESIDUAL GRAVITY, BOREHOLE POSITIONS AND DOLOMITE HAZARD ZONATION WITH PROPOSED REHABILITATION AREA

VGI7148S19/1

APPENDICES BOREHOLE PROFILES

APPENDIX 1

1

1.

INTRODUCTION This report presents the results of a dolomite stability investigation carried out along the proposed pipeline route in Bluebell Street, Carletonville, which will realign a section of the existing water pipeline which has been affected by a sinkhole. The purpose of the investigation is to determine the subsurface conditions along the proposed alignment and provide recommendations on the way forward in terms of wet service design and dolomite risk management. These investigations involved field inspections, a drilling programme, analysis and reporting.

2.

TERMS OF REFERENCE VGIconsult is appointed by Morad to conduct dolomite stability investigations at various sinkhole sites in the Merafong City Local Municipality area.

3.

AVAILABLE INFORMATION Information sources include: 3.1. Topographic Data Topographic Map, 1: 50 000 Scale Series: issued by the Chief Directorate: Surveys and Mapping, Department of Land Affairs: Sheet Name Carletonville

Reference 2627AD

3.2. Geological Information Geological Map, 1: 250 000 Scale Series: issued by the Geological Survey of South Africa (Council for Geoscience): Sheet Name West Rand

Reference 2626

3.3. Industry Standards o

South African National Standard SANS 1936 Parts 1 – 4 (2012).

o

South African National Standard SANS 2001-BE3: 2012, Construction works Part BE3: Repair of sinkholes and subsidences in dolomite land.

o

South African National Standard SANS 633:2012, Edition 1 (ISBN 978-0-62627631-7), Soil profiling and rotary percussion borehole logging on dolomite land in Southern Africa for engineering purposes.

o

Environmental Earth Sciences, Springer-Report: “A Performance Based Approach to Dolomite Risk Management” by D Buttrick, N Trollip, R Watermeyer, N Pieterse, A Gerber, Volume 64, Issue 4, p1127 – p1138, dated 2011.

o

South African National Standards: The Application of the National Building Code: SANS 10400, Part A: General principles and requirements and Part B: Structural Design, (2004).

2

o

Council for Geoscience/South African Institute of Engineering and Environmental Geologists (2003): Guideline for engineering-geological characterisation and development of dolomitic land.

o

Council for Geoscience (2007): Consultants Guide: Approach to Site on Dolomite Land.

o

Department of Public Works (PW344), September 2010: Development of Infrastructure on Dolomite. Manual for Consultants.

o

Annals of the Geological Survey of South Africa: “Subsurface subsidences and sinkholes caused by lowering of the dolomitic water-table on the Far West Rand Gold Field of South Africa” by RJ Kleywegt and DR Pike, Volume 16, p77 – p105, dated 1982.

Appropriate

3.4. Geohydrological Information Groundwater information is made available by the Department of Water Affairs through the National Groundwater Information System (NGIS) which offers read-only access to data from: o o o

National Groundwater Archive (NGA); Water Management System (WMS); and Hydstra [http://www.dwa.gov.za/chart/]).

In addition, the report “Geohydrology Guideline Development: Implementation of Dolomite Guideline – Phase 1, Activities 19 & 28: Desktop development of a Dolomite Hydrogeological Compartment Map and explanation booklet (Report), dated November 2009, Project Number: 14/14/5/2, Authors: Martin Holland: Water Geosciences Consulting, Frans Wiegmans: Golder Associates”, was consulted.

4.

DESCRIPTION OF THE STUDY AREA The location of the affected area is displayed on Figure 1. The proposed pipeline alignment and sinkhole location are displayed on Figure 2. The regional topography of the area falls from 1550m AMSL in the east to 1540m AMSL in the west.

5.

PROCEDURES USED IN THIS STUDY As dolomite hazard assessment is an empirical science that is constantly changing, these succinct background notes are provided to contextualise the procedures used in these investigations, in time and content. The objective is to provide an understanding of the process currently followed in classifying the site and the determination of appropriate risk management requirements, should it be required at some future date. 5.1. Assimilation of Available Data Data collected from the client, the Council for Geoscience and the VGIconsult databases together with available geological and geohydrological data are first assimilated.

3

5.2. Map Production (Projection, Co-ordinate System and Datum) All the drawings in this report are produced using a Geographic Information System (GIS). The projection information of the figures and drawings in this report listed below: Projection surface: Projection orientation: Datum or reference ellipsoid: Central Meridian: False easting and northing: Scale factor:

Mercator (cylinder) Transverse aspect World Geodetic System 84 In degrees (27 for this study) Zero degrees 1

The drawings and figures are co-ordinated in metres latitude (7 digit value) and longitude (5 or 6 digit value). 5.3. Geophysics (Gravity Method) The gravity method is the most widely used remote sensing technique applied on dolomite land. Variations in the earth’s structure and composition give rise to variations in density. Indirectly the density variations are determined by measuring the gravity field which allows the determination of location, form and distribution of causative geological factors. A gravity survey of a dolomitic terrain can be used to help determine dolomite bedrock configuration (bedrock topography) and allows various deductions to be made about tectonic processes. The existing gravity survey contour data is displayed in Drawing VGI7148 S19/1. 5.4. Rotary Percussion Boreholes 5.4.1. Current investigation Eleven (11) boreholes were drilled along or near to the pipeline alignment: Drilling method: Drilling Contractor: Drilling Machine: Hammer diameter: Hammer type: Compressor: Delivery:

Rotary percussion JK Developments Thor 5000 165 mm Button Atlas COPCO 21,1m3/min @ 1800kPa

The borehole logs are presented in Appendix 1 and summarised in Table 1.The coordinates of the boreholes drilled during this investigation follow: Borehole Number 7148-01 7148-02 7148-03 7148-04 1

Co-ordinates Y -39831 -39864 39908 -39915

1

X 2918504 2918503 2918493 2918490

The X- and Y-coordinates conform to the South African Coordinate System as set in the national control survey network maintained by the Chief Directorate: Surveys and Mapping of the Department of Land Affairs. The X- and Y-values are given in metres latitude (7 digit value) and longitude (5 or 6 digit value). These coordinates are projected using the Gauss Conform Projection which is the Transverse aspect of the Mercator projection. The reference ellipsoid is the WGS84 (Hartebeeshoek 1994) ellipsoid.

4 Borehole Number 7148-05 7148-06 7148-07 7148-08 7148-09 7148-10 7148-11 7148-17 7148-18 7148-19 7148-20 7148-21 7148-24

Co-ordinates Y -39962 -39988 -39785 -39756 -39931 -39716 -39699 -39923 -39919 -39915 -39911 -39901 -39731

1

X 2918480 2918476 2918503 2918495 2918497 2918483 2918441 2918500 2918501 2918502 2918503 2918506 2918486

The positions of the boreholes are displayed on Drawing VGI7148 S19/1. Boreholes drilled around the sinkhole are included in this list for completeness sake. 5.5. Hazard Characterisation Procedure New National standards (SANS 1936, 2012) require use of internationally accepted terminology. The applicable terminology and its definition (with previous term used) are given below: 5.5.1. Terminology 5.5.1.1.

Hazard Source of potential harm. Hazard is the function of magnitude (of the events), area, and frequency.

5.5.1.2.

Inherent Susceptibility (Inherent Risk) A reflection of the geological susceptibility of a karst area to an event (sinkhole or subsidence). Inherent Susceptibility is expressed in terms of three broad categories, namely low, medium and high, typically, but not exclusively, denoting anticipated number of events per area over time.

5.5.1.3.

Inherent Hazard Class (Inherent Risk Class) A site is characterised in terms of eight standard inherent hazard classes, denoting the likelihood of an event (sinkhole or subsidence) occurring (susceptibility) as well as its likely size (diameter). The larger the Inherent Hazard Class (IHC) number, the greater the likelihood of the event occurring and the larger its potential size should it occur, for each respective inherent susceptibility category (low, medium, high).

5.5.1.4.

Hazard Rating The number of events per hectare that have occurred over a 20 year period due to human impact.

5.5.1.5.

Tolerable Hazard Rating (Acceptable Development Risk) The hazard rating is expressed as tolerable where the number of events experienced is less than and including 0.1 events per hectare per 20 years (preferably tending to 0 per hectare) that is exceeding the return period of

5

200 years and intolerable where the number of events experienced exceeds 0.1 events per hectare per 20 years (return period less than 200 years). 5.5.1.6.

Return Period Known as a recurrence interval and is an estimate of the interval of time between events of a certain size.

5.5.1.7.

Subsidence (Doline) Shallow, enclosed depression. In past South African literature subsidence, as defined above, is synonymous with doline. The term subsidence is substituted to prevent contradiction with international literature.

5.5.1.8.

Sinkhole A feature that occurs suddenly and manifests itself as a hole in the ground.In international literature the term sinkhole is often synonymous with doline.

5.5.1.9.

Dolomite Land land underlain by dolomite or limestone residuum or bedrock (or both), within the Malmani Subgroup and Campbell Rand Subgroup, typically at depths of no more than a)

60min areas where node-watering has taken place and the local authority has jurisdiction, is monitoring and has control over the groundwater levels in the areas under consideration; or

b)

100 m in areas where de-watering has taken place or where the local authority has no jurisdiction or control over groundwater levels.

5.5.1.10. Event Occurrence [or change of a particular set of circumstances], in the context of this standard referring to a sinkhole or subsidence. An event can be one or more occurrences, and can have several causes. An event can consist of something not happening. An event can sometimes be referred to as an “incident” or “accident”. 5.5.1.11. Potential Loss of Support Refers to the removal of support below the foundation due to a nominal sinkhole or subsidence event. In proposing suitable foundation types in D3 areas, consideration should be given to the potential loss of support which could be anticipated for the designated Inherent Hazard Class based on the nascent2 sinkhole size. The philosophy to be applied to the design of the foundations is that in the event of catastrophic loss of support, there is sufficient time for occupants to safely escape after the occurrence of the sinkhole, and the level of expected damage associated with soil movements unrelated to sinkhole formation in near surface horizons is kept within reasonable limits. 2

Adj. beginning to develop

6

5.5.2. Assessment Procedure The hazard characterisation procedure (previously referred to as “risk” characterisation procedure in South African literature) is in accordance with the peer reviewed paper “A performance based approach to dolomite risk management”: The available information, geophysical data, borehole data and geohydrological information gathered during the investigation has been pooled and reviewed permitting the formulation of a perspective concerning the characterisation of the stability of the site. The predominant mobilising agencies considered in this investigation are major groundwater level fluctuations (>6m), ingress of water, ground vibrations and gravity. Use is made of a generalised list of evaluation factors to evaluate the hazard. These factors are as follows: o Receptacle development; o Mobilising agencies, particularly ingress of water from leaking services; o Potential sinkhole development space; o Nature of the blanketing layer; o Mobilisation potential of the blanketing layer; o Bedrock morphology. Receptacles or disseminated receptacles refer to any voids or cavities in the dolomite bedrock or in the overburden capable of receiving mobilised materials. Receptacles are assumed to be present as no reliable geophysical tool exists to determine the location of these features. Consequently the information gathered from boreholes, including penetration times, air loss, hammer action, etc, combined with geophysical and geological information are used to formulate an impression of the degree of voids. The potential sinkhole development space, where used, refers to the expected maximum size sinkhole that conservatively may be anticipated to be generated if sustained ingress of water were to occur. This factor is related to the depth of the receptacles or disseminated receptacles. The gravity survey, combined with borehole information strongly guides the appraisal of this factor. The nature of the material covering the receptacles, be they above or in the bedrock, determines the susceptibility of the subsurface material to erosion by ingress of water. The presence of materials such as shales or intrusives, which can act as aquitards, serve to reduce the mobilisation potential and enhance the stability. In the case of dramatic groundwater level fluctuations the susceptibility of the soil material to mobilisation (i.e. consolidation settlement - subsidence formation, or ravelling and arch failure - sinkhole formation, due to pore pressure changes in soils), is strongly influenced by the position of the original groundwater level in the subsurface profile. In assessing the susceptibility of a subsurface profile to sinkholes and subsidences due to groundwater level drawdown, attention is given to the nature and extent of the material below the groundwater level. For example in the case of compressible dolomite residuum, as the groundwater recedes, pore pressures in the residual dolomite soils, typically characterized by high void ratios, gradually dissipate and the effective stress on the soil increases causing consolidation of the compressible material.

7

A surface depression may occur gradually due to the load of the near-surface materials on the deeper lower density materials that settle into a denser state. The general maximum magnitude of natural groundwater fluctuation in the Gauteng dolomites is in the order of 5m (Hobbs, 2004; Holland, 2007). Hence artificial groundwater level drawdown is generally defined as drawdown exceeding 6m. Experience shows that groundwater level drawdown (beyond seasonal variations) has the greatest negative impact on dolomite stability in areas of shallow groundwater levels (30 m or shallower) i.e. deeper (> 30 m) groundwater levels, pose less of a negative impact on stability, in the event of groundwater level drawdown or dewatering. However, where groundwater drawdown occurs in areas of deeper groundwater, the size of instability is typically anticipated to be large to very large. In view of the factors discussed above the following characteristics have been extracted from the gathered information during the assessment process: o borehole position relative to the gravity data. o collar elevation. o depth to dolomite bedrock*. o depth to potential receptacles. o depth to the present and original groundwater level. o nature and thickness of blanketing layer i.e. material type, penetration times, etc. o position of the bedrock with respect to the present and original groundwaterlevel. o thickness and nature of the soil materials above and below the present and original groundwater level. *In the context of this report the concepts of thickness and depths for subsurface horizons are used as follows: Thicknesses (Alluvium / Colluvium / Residuum)

Depths Range in m 0-2/4 2/4-8/12 8/12-16/24 16/24-36/44 More than 40

Appellation Near-surface Shallow Intermediate Great Depth Very Great Depth

Range in m 0-8/12 8/12-16/24 16/24-36/44 36/44 and greater -

Appellation Thin Intermediate Thick Very Thick -

Inherent susceptibility is a reflection of the geological susceptibility of a karst area to an event (sinkhole or subsidence formation) andis expressed in three broad categories, namely low, medium and high. The following reference to incidences, gives a perspective of the magnitude of problems encountered in each of the of hazard zones in research areas. It is important to note that these figures are largely derived from developments not effectively and appropriately designed or maintained. Inherent Susceptibility

Anticipated events per hectare over time (magnitude of problem)*

LOW

0 up to and including 0.1 events per hectare anticipated but occurrence of events cannot be excluded. Return Period is greater than 200 years.

MEDIUM

Greater than 0.1 and less than and equal to 1.0 events per hectare. Return period is between 200 and 20 years.

8 Inherent Susceptibility HIGH

Anticipated events per hectare over time (magnitude of problem)* Greater than 1.0 events anticipated per hectare. Return period is less than 20 years.

* that have occurred per hectare in a 20 year period in the "type" areas (statistics based on poor service design and maintenance)

The study area is characterised in terms of eight standard Inherent Hazard Classes. These classes denote the chance of a sinkhole or subsidence occurring as well as its likely size (diameter). The terminology used in terms of likely size of an event (sinkhole or subsidence) is defined as follows: Maximum diameter of surface manifestation (in metres)

Terminology

<2

Small-size

2-5

Medium-size

5-15

Large-size

> 15

Very large-size

The larger the Inherent Hazard Class number, the greater the chance of a sinkhole or subsidence occurring and the larger its potential size should it occur for each of the inherent susceptibility categories. The meaning/definition of each Inherent Hazard Class is as follows: Inherent Hazard Class Class 1 Areas Class 2 Areas Class 3 Areas Class 4 Areas Class 5 Areas Class 6 Areas Class 7 Areas Class 8 Areas

Characterisation of Area Areas characterised as reflecting a low inherent susceptibility of all sizes of events occurring. Areas characterised as reflecting a medium inherent susceptibility of small-size events occurring. Areas characterised as reflecting a medium inherent susceptibility of medium-size events occurring. Areas characterised as reflecting a medium inherent susceptibility of large-size events occurring. Areas characterised as reflecting a high inherent susceptibility of smallsize events occurring. Areas characterised as reflecting a high inherent susceptibility of medium-size events occurring. Areas characterised as reflecting a high inherent susceptibility of largesize events occurring. Areas characterised as reflecting a high inherent susceptibility of very large-size events occurring.

In this report Inherent Susceptibility is defined in terms of ingress of water and groundwater level drawdown reflected by two Inherent Hazard Class designations separated by a double forward slash, i.e.Inherent Hazard Class (ingress of water) // Inherent Hazard Class (groundwater level drawdown) 5.6. Monitoring Designations According to SANS 1936 Part 4 (2012) Monitoring Designations must be identified and delineated according to the Inherent Susceptibility characterisation of the site and

9

knowledge of problems which could impact on the infrastructure on site. The generic Monitoring Activities considered appropriate for dolomite land are as follows: Annotation

A

B

C

D

Activity* Visual inspections of ground, structures and above ground infrastructure (e.g. buildings, taps, gardens, private and public open space etc.) and dry services, sleeves, ducts, manholes and facility chambers for water ingress: Examine buildings for cracks. Visual checks for outside dripping taps and pressure valves. Visual checks for damp or moss grown areas. Visual check for over-wetting of gardens. Visual check for blocked drainage ports in garden walls. Visual check for cracks in the ground. Visual inspection of stormwater systems: Visual checks for debris in open storm water channels at, for example, the start of the rainy season and after heavy storms. Visual checks for water flowing out of stormwater manholes at the start of the rainy season and after heavy storms. Search for ground cracks and cracks in lined and unlined channels. Testing of wet-services for leaks: Regular air and water tests on wetservices. In waste water and stormwater pipes with a diameter greater than 100mm wet-services to be inspected by camera. Monitoring of structures and ground levels: In many instances visual inspections may not be sufficient: It may be necessary to undertake precision ground-surface levelling, particularly in areas that have been rehabilitated after a ground movement event. Such levelling must be undertaken by a surveyor, recorded and stored in the databank and appropriate actions taken when excessive settlement continues.

Reaction

Any evidence of cracking or ground settlement should immediately be reported and investigated. Any evidence of blockages should be reported and cleared immediately, or cracks repaired once settlement is halted. Any water ingress in dry services, sleeves, ducts, manholes and facility chambers shall be reported, and point of entry repaired and investigated.

Purpose

Monitor, control and prevention of concentrated ingress of water

Any leaks to be reported and repaired immediately.

Any evidence of movement must be reported and investigated and appropriate repair work undertaken.

Monitor the effects of concentrated ingress of water or groundwater level drawdown

10 Annotation

E

Activity* Monitoring of the groundwater level: This activity not only entails the measuring and recording of the groundwater level, but also the analysis and understanding of groundwater level trends over time and the control of excessive [beyond seasonal fluctuations] groundwater level drawdown: Drill and equip strategic boreholes with the necessary equipment to measure the groundwater level. Recorded groundwater level, monitoring well number, date and other relevant observations. Analyse groundwater level trend over time on a regular basis. Report artificial/excessive groundwater level drawdown to Municipality and the Department of Water Affairs. Investigate cause of artificial/excessive groundwater level drawdown. Arrest artificial/excessive groundwater level drawdown.

Reaction

Evidence of lowering (exceeding 6m) must be reported to Municipality and the Department of Water Affairs and appropriate action taken to ensure the groundwater level returns to within natural seasonal fluctuations.

Purpose

Monitor, control and prevention of groundwater level drawdown

*If there is no evidence of a particular problem, this result should be recorded.

Note that in SANS 1936 Part 4 (2012), pg 15, the visual inspection of dry services, sleeves, ducts, manholes and facility chambers is included as a separate monitoring activity (as Annotation D), with the Annotations D and E as listed above, annotated as E and F. For simplicity sake this activity has been included in Annotation A above. The Frequency with which each Activity is to be performed is selected from the following categories: Annotation DAILY () WEEKLY () 1 () 3 () 6 () 12 () 24 () NA () tbd ()

6.

Frequency Activities to be undertaken daily. Activities to be undertaken weekly. Activities to be undertaken once a month. Activities to be undertaken quarterly. Activities to be undertaken bi-annually. Activities to be undertaken annually. Activities to be undertaken once every two years. NO ACTION REQUIRED CURRENTLY TO BE DETERMINED

GEOLOGY AND GEOHYDROLOGY 6.1. General Geology The site is underlain by chert and dolomite of Malmani Subgroup of the Chuniespoort Group, Transvaal Supergroup with the possibility of intrusive materials in the form of dykes. The various lithological units and their weathered derivatives, recorded on the site are as follows:

11

Lithostratigraphic Unit

Lithology

Intrusive Eccles Formation, Malmani Subgroup, Chuniespoort Group, Transvaal Supergroup

Syenite and associated soil derivatives. Dolomite, chert and associated soil derivatives.

Unconsolidated materials deemed to be various recent deposits (most likely 24 Ma [Miocene Epoch] and younger) are anticipated to mantle the hard rock geology (and residual product thereof). The material varies in thickness, sedimentological- and geotechnical properties: Post-Gondwana Deposits Colluvium

Soils of sandy, silty or clayey composition or gravels

6.2. Local Geology

o

-

0-9

-

-

-

9-15

-

0-21

-

22-26

-

21-22

-

0-2

-

-

-

0-6

-

6-9, 16-21

-

21-23

-

-

-

-

-

0-9

-

0-2

-

-

-

2-12

-

0-15

-

36-41

-

15-36, 41-46

-

0-6

-

26-30

-

6-26

-

0-18

-

18-42

-

48-49

-

0-10

-

10-25

-

25-27

-

0-40

-

-

-

40-48

-

2-14

Dolomite Bedrock (m) – (m) (mAMSL)

Highly weathered dolomite (m) – (m)

Manganiferrous Soils

Residual Syenite

Ferroan Soils

7148-01 1545 7148-02 1545 7148-03 1545 7148-04 1546 7148-05 1549 7148-06 1551 7148-07 1543 7148-08 1542 7148-10 1541 7148-11 1539 7148-24 1541

Blanketing Layer (m) – (m) Chert Dolomite Residuum Residuum Fines subordinate

BH No. (Collar Elev. m AMSL)

Colluvium

A summary of the material intercepted in boreholes drilled on the site is reported here for ease of reference:

15-24 1530 26-29 1524 14-20 1531 23-29 1523 9-15 1540 12-18 1539 46-52 1497 30-46 1512 49-55 1492 27-30 1512 48-54 1493

Cavity (m)–(m)

9-16 44-48 -

Chert residuum Chert residuum is intercepted at surface. The horizon is of variable thickness (2m to 21m).

12

o

Dolomite residuum (manganiferous material) Dolomite residuum (manganiferous material /wad) is intercepted at variable depths (3m to 24m). The horizon is of variable thickness.

o

Problematic conditions in the overburden above the groundwater level: Cavernous conditions including disseminated voids are intercepted in Borehole 7148-04 from 9m to 16m and from 44m to 48m in Borehole 7148-10. Sample- and air loss are reported in seven boreholes drilled along the proposed alignment and around the sinkhole.

o

Dolomite bedrock conditions: Dolomite rock, either weathered or hard rock is confirmed at variable depths (0m to 48m).

6.3. Geohydrology The site is located in the Oberholzer Dolomite Groundwater Compartment. During the 1960’s and 70’s interest focussed on mining related issues of control and disposal of inflow water. A policy of dewatering was implemented for the Venterspost and Oberholzer Compartments (1964), Bank Compartment (1969) and Gemsbokfontein West Compartment (late 1980’s). The OWL depth and elevation in proximity to the site is 81m and 1469m AMSL respectively. During the drilling process the driller notes the depth of groundwater strike/s. The driller also observes the hole after drilling (typically 24 hours after completion) for the presence of groundwater, using a dip meter tool. According to the driller all boreholes were dry. According to Sibanye Mine data (2005) the current groundwater level is 1220m AMSL (i.e. 330m deep or 249m below OWL) in the general site area. 6.4. Background: July 2016 Sinkhole A sinkhole occurred south of No 40 Bluebell Road and north of the R501 National Road, Carletonville on 13 July 2016. A site inspection was conducted by VGIconsult on 15 July 2016. The following was observed: An 8m x 4m diameter sinkhole extending to a depth of approximately 7m. An exposed broken and leaking 200mm diameter (cement or asbestos) water line in sinkhole area. Various clamps (X3) on the waterline within 2m (on both sides) from the current broken position of the waterline indicating problems previously encountered on this line. An existing water runoff channel has been compromised by previous ground works and is shaped as such allowing surface water ponding at the position of the sinkhole. Subsurface erosion of highly erodible and compressible dolomite residuum (wad) at depth and the development of the sinkhole is likely to have taken place over a prolonged period of time. In addition, surface run-off water ponds in the area of the sinkhole, potentially contributing to the formation of the sinkhole.

13

DOLOMITE HAZARD CHARACTERISATION 7.1. Site investigation and Dolomite Hazard Assessment Procedures Summarised information concerning the hazard characterisation of the proposed alignment is provided in Table 1 of this report and the dolomite hazard zonation is displayed on Drawing VGI7148S19/1. 7.2. Dolomite Hazard Zone 1 (Hazard Class 4/7//1) A summary of subsurface conditions within Dolomite Hazard Zone 1 follows: a)

Blanketing Layer The blanketing material is intercepted in boreholes drilled within the zone are summarised in the table below:

7148-10 1541 7148-11 1539 7148-24 1541

b)

Chert Residuum Pre or Post Malmani Subgroup material (m-m)

Borehole Number with collar elevation in m AMSL

Transported material (m-m)

7.

Fines subordinate (m-m)

-

-

-

0-18

18-42

-

-

-

0-10

10-25

-

-

-

0-40

-

Fines predominant (m-m)

Dolomite Residuum (m-m)

Dolomite Bedrock Hard rock dolomite is typically intercepted at great depth: Borehole Number with collar elevation in m AMSL 7148-10 1541 7148-11 1539 7148-24 1541

c)

Soft and weathered dolomite rock (Malmani Subgroup) (m-m) 48-49 25-27 40-48

Dolomite Bedrock (Malmani Subgroup) m and m AMSL 49-55 1492 27-30 1512 48-54 1493

Gravity Data According to the gravity data this zone straddles a gentle gravity gradient (refer to Drawing VGI7148 S19/1.

d)

Dolomite bedrock relative to OWL The OWL is 1469m AMSL or approximately 81m deep. The gravity data indicates that dolomite bedrock is above the OWL, which is confirmed by the drilling programme.

14

A summary of the hazard characterisation follows: e)

Hazard Characterisation i.

Blanketing Layer The blanketing layer is relatively thick. The blanketing layer consists of chert and dolomite residuum. These materials are anticipated to be characterised by good internal drainage characteristics. Prolonged ingress may readily lead to erosion and sinkhole or subsidence formation.

ii.

Potential Development Space In general the depth to dolomite bedrock, as well as the groundwater level (which acts as a base level for erosion) and the potential receptacles determine the Potential Development Space (PDS). The PDS is characterised as, typically, large.

iii.

Hazard Classification (with Ingress of Water as a Triggering Mechanism) The blanketing layer is relatively thick. Dolomite residuum (wad) typically blankets the dolomite bedrock. Sample and air loss was recorded. The zone is characterised as largely reflecting a medium to high susceptibility of large-size sinkhole and subsidence formation with respect to ingress of water, i.e. Inherent Hazard Class 4/7.

iv.

Hazard Classification (with Groundwater Drawdown as a Triggering Mechanism) The original groundwater level is anticipated at 81m and is currently at over 300m depth. Experience during the initial period of dewatering indicated that the effect of major drawdown was most pronounced when the OWL was 30m or shallower, which is not the case for this site. The OWL and current groundwater level are well within dolomite rock. The susceptibility to sinkhole and subsidence formation in the event of anthropogenic groundwater drawdown is considered to below, i.e. Inherent Hazard Class //1.

v.

Impact of Lowering of the Groundwater Level/Base Level of Erosion on the Action of Ingress In the event that the groundwater level is drawn down significantly (6m or more), the hazard classification remains unchanged.

vi.

Composite Hazard Classification The composite hazard classification is Inherent Hazard Class 4/7//1, defined as an area largely reflecting a medium to high susceptibility of large-size sinkhole and subsidence formation with respect to ingress of water and a low susceptibility of all-size sinkhole and subsidence formation with respect anthropogenic groundwater level drawdown.

15

7.3. Dolomite Hazard Zone 2 (Hazard Class 5/6(3)//1) A summary of subsurface conditions within Dolomite Hazard Zone 1 follows: a)

Blanketing Layer The blanketing material is intercepted in boreholes drilled within the zone are summarised in the table below:

b)

Pre or Post Malmani Subgroup material (m-m)

7148-01 1545 7148-02 1545 7148-03 1545 7148-04 1546 7148-05 1549 7148-06 1551 7148-07 1543

Chert Residuum

Transported material (m-m)

Borehole Number with collar elevation in m AMSL

Fines subordinate (m-m)

-

-

-

0-9

-

-

-

-

0-21

22-26

-

-

-

0-2

-

-

-

-

0-6

6-9, 16-21

-

-

-

-

-

-

-

-

0-2

-

-

-

-

0-15

36-41

Fines predominant (m-m)

Dolomite Residuum (m-m)

Dolomite Bedrock Dolomite is typically intercepted at shallow depths: Borehole Number with collar elevation in m AMSL 7148-01 1545 7148-02 1545 7148-03 1545 7148-04 1546 7148-05 1549 7148-06 1551 7148-07 1543

c)

Soft and weathered dolomite rock (Malmani Subgroup) (m-m) 9-15 21-22 2-14 21-23 0-9 2-12 15-36, 41-46

Dolomite Bedrock (Malmani Subgroup) m and m AMSL 15-24 1530 26-29 1524 14-20 1531 23-29 1523 9-15 1540 12-18 1539 46-52 1497

Gravity Data According to the gravity data this zone straddles a gravity high area (refer to Drawing VGI7148 S19/1.

16

d)

Dolomite bedrock relative to OWL The OWL is 1469m AMSL or approximately 81m deep. The gravity data indicates that dolomite bedrock is above the OWL, which is confirmed by the drilling programme.

A summary of the hazard characterisation follows: e)

Hazard Characterisation i.

Blanketing Layer The blanketing layer is typically thin. The blanketing layer consists of chert and dolomite residuum. These materials are anticipated to be characterised by good internal drainage characteristics. Prolonged ingress may readily lead to erosion and sinkhole or subsidence formation. The shallow rock is anticipated to be incised by relatively narrow grykes infilled by low density, and even cavernous, dolomite residuum.

ii.

Potential Development Space In general the depth to dolomite bedrock, as well as the groundwater level (which acts as a base level for erosion) and the potential receptacles determine the Potential Development Space (PDS). The PDS is characterised as, typically, medium.

iii.

Hazard Classification (with Ingress of Water as a Triggering Mechanism) A typical shallow dolomite environment is anticipated in this zone and the area of the sinkhole. Sample and air loss was recorded. The following is typically known of shallow dolomite areas (based on experience): Existence of a highly variable dolomite bedrock topography with deep weathering along linear features such as fractures; Occurrence of insoluble weathering product of dolomite rock. This material is highly compressible and mobilisable; Particularly problematic environment mainly due to the fact that the overburden is thin and smaller quantities of water are required to mobilize the overburden resulting in sinkholes or subsidences; Dolomite may outcrop at surface, sometimes as actual rock masses, but often as isolated pinnacles and large floaters (detached from main bedrock); The undulating micro-topography of a shallow dolomite environment may typically not be discerned in gravity data. The zone is characterised as largely reflecting a high susceptibility of small- to medium-size sinkhole and subsidence formation (sub-areas may comprise a medium susceptibility of medium-size sinkholes and subsidences) with respect to ingress of water, i.e. Inherent Hazard Class 5/6(3).

iv.

Hazard Classification (with Groundwater Drawdown as a Triggering Mechanism) The original groundwater level is anticipated at 81m and is currently at over 300m depth. Experience during the initial period of dewatering indicated that the

17

effect of major drawdown was most pronounced when the OWL was 30m or shallower, which is not the case for this site. The OWL and current groundwater level are well within dolomite rock. The susceptibility to sinkhole and subsidence formation in the event of anthropogenic groundwater drawdown is considered to be low, i.e. Inherent Hazard Class //1. v.

Impact of Lowering of the Groundwater Level/Base Level of Erosion on the Action of Ingress In the event that the groundwater level is drawn down significantly (6m or more), the hazard classification remains unchanged.

vi.

Composite Hazard Classification The composite hazard classification is Inherent Hazard Class 5/6(3)//1, defined as an area largely reflecting a high susceptibility of small- to mediumsize sinkhole and subsidence formation (sub-areas may comprise a medium susceptibility of medium-size sinkholes and subsidences) with respect to ingress of water and a low susceptibility of all-size sinkhole and subsidence formation with respect anthropogenic groundwater level drawdown.

8.

CONCLUSIONS 8.1. Results of the Drilling Programme The boreholes intercept chert and dolomite residuum of variable thickness. Cavernous conditions, including disseminated voids, are intercepted in some of the boreholes. Weathered dolomite bedrock/hard rock dolomite is intercepted atvariable depths (0m to48m). All the boreholes were recorded as “dry” 24 hours after drilling. The groundwater level is anticipated at 200m depth, whilst the OWL is at 1469m AMSL or 81m deep. ‘ 8.2. Dolomite Hazard Characterisation The pipeline alignment is characterised by two dolomite hazard areas as follows: Dolomite Hazard Zone

Hazard Classification

1

4/7//1

2

5/6(3)//1

Description Area largely reflecting a medium to high susceptibility of largesize sinkhole and subsidence formation with respect to ingress of water and a low susceptibility of all-size sinkhole and subsidence formation with respect anthropogenic groundwater level drawdown. Area largely reflecting a high susceptibility of small- to mediumsize sinkhole and subsidence formation (sub-areas may comprise a medium susceptibility of medium-size sinkholes and subsidences) with respect to ingress of water and a low susceptibility of all-size sinkhole and subsidence formation with respect anthropogenic groundwater level drawdown.

18

9.

RECOMMENDATIONS The measures and recommendations outlined below are aimed at reducing the likelihood of sinkhole or subsidence formation along the new pipeline route. Recommendations are based on experience gained during the investigation and rehabilitation of more than 100 instability features (sinkholes and subsidences) in the Ekurhuleni Metropolitan Municipality (EMM), City of Tshwane and West Rand District Area. 9.1. Improvement of subsoil conditions Along the eastern portion of the pipeline alignment the dolomite bedrock is encountered at relatively shallow depths below natural ground level. Based on the subsurface conditions encountered during the drilling programme around the sinkhole, disseminated receptacles and cavernous conditions are recorded above the OWL within dolomite residuum (wad) in Boreholes 7148-4 (9m to 17m), 7148-9 (1m to 10m) and 7148-21 (21m to 31m). A backfill grouting programme is required in the area of Boreholes 7148-2 and 7148-10. In Borehole 7148-2 a cavity in bedrock is intercepted between a depth of 22m and 25m. In Borehole 7148-10 a void is intercepted between a depth of 44m and 48m. It is recommended that two boreholes be drilled, east and west of the position of these two boreholes where a void and a cavity were encountered i.e. within 3m to the west and east. The position of the two problematic boreholes should also be re-drilled on its original position. Based on the above findings, Improvement of the subsurface conditions in the area surrounding the sinkhole will require a backfill grouting programme to fill erosion voids, zones of very soft dolomite residuum (wad) and cavities, intercepted in Boreholes 7148-4 (9m to 17m), 7148-9 (1m to 10m) and 7148-21 (21m to 31m). Multi stage grouting should be planned at a series of primary and secondary points, with the possibility of a tertiary stage if found necessary. All the primary points will be drilled first on a 3m grid spacing, followed by the secondary points some days later. The secondary points will be positioned midway between the primary points. The grouting of each point will be carried out from the bottom up, which is referred to as upstage grouting, or a combination of methods may be required, depending on condition and results, also including downstage grouting. The pumping rates and pressure induced to inject the grout should be selected carefully and monitored throughout the grouting process as excessive pressure will cause fracturing of the overburden resulting in ground heave and potentially more damage. The grouting mixture generally used, with a slump of between 25mm and 75mm, does not need to meet any strength requirements as the objective is not to form a structural element in the ground but to backfill voids and compact problematic zones. As a point of departure provision should be made for the following grouting points in the bill of quantities: Area Surrounding Sinkhole Area 7148-4 Erosion tunnel west of 7148-3 7148-9 7148-21 Along new pipeline route 7148-2 7148-10

Number of Boreholes

Depth (m)

11 4 5 5

26 36 18 36

3 3

30 53

19

It should be noted that the above recommended grouting depths are an estimate based on existing borehole information.

All the grouting boreholes should be drilled into at least 4m of solid dolomite bedrock. The injection of grout should not exceed 0,1 MPa (or 10 Bar). It is recommended that very low grout pressures are used (less than 3 Bar). Provision should be made in the bill of quantities for 1,5m3 per meter drilling 2MPa strength grout. Clear and landscape (contouring) of the site will be required after completion of the grouting programme. Provision should be made in the bill of quantities for 1 concrete cube test per day. The field report on the grouting programme, should include the applied pressure per meter (bar) and volume of grout (litre/metre) pumped at each grouting point. Also record any voids and their height. Care should be taken during the grouting programme to ensure that no damage is caused to surrounding structures. A crack survey is recommended before grouting work commences (both of the structures and the ground). 9.2. Precautionary Measures Water is a triggering mechanism, in the majority of cases, of distress in dolomitic/limestone areas. It is therefore imperative that the concentrated ingress of water into the ground be avoided at all times. SANS 1936, Part 3 (2012): “Design and construction of buildings, structures and infrastructure” is in the public domain. The contents of SANS 1936 should be applied except where more stringent requirements are specifically required by the local authority. In accordance with SANS 1936, Part 3 (2012) all subsurface wet services should comprise of HDPE butt-welded pipes. It is recommended that HDPE butt-welded pipes, as specified by SANS 1936 Part 3 for areas underlain by dolomite, be used. 9.3. Open works and general construction activities Trenches and open works should be inspected by a Dolomite Risk Specialist to: o o

permit the assessment and development of a comprehensive record of the surficial conditions and assess if adverse ground conditions are present e.g. palaeo-karst structures.

This procedure allows for the adjustment of construction methods, i.e. special bedding requirements, additional excavation and compaction, or pipe protection measurements. Delineated problems can then be treated with greater vigilance during the ongoing maintenance of the line. Ongoing interaction between the Dolomite Risk Specialist and the Consulting Engineers responsible for the project is recommended. 9.4. Stormwater Management Absolutely no ponding of water should be permitted along the route. An essential component of risk management is ensuring that stormwater is efficiently and effectively removed from the proximity of infrastructure and safely distributed or deposited into either the municipal stormwater system or natural river courses.

20

9.5. Monitoring Actions The long term monitoring actions for the pipelineis presented as follows:

Monitoring Designation (ABC)3(DE)na Explanation A

Visual inspections of ground and above ground infrastructure quarterly.

B

Visual inspection of stormwater flow quarterly.

C

Testing of pipeline for leaks quarterly.

D

Monitoring of structures and ground levels not required. Although not applicable to the site, any substantial lowering of the groundwater level may induce ground subsidence events in the general area. The groundwater level should be maintained within natural seasonal fluctuation limits i.e. dewatering resulting from the artificial drawdown of the groundwater level cannot be permitted.

E

9.6. Database of Ground Movement and Stability Conditions It is recommended that the sinkholes that occurred and all repair, upgrade and soil improvement work conducted is added to the Municipal’s database of ground movement events. Detailed historical records of this nature are most useful in developing a clearer perspective on the stability situation on site and management of a pro-active maintenance strategy.

10.

GENERAL These findings are based upon our interpretation of the data recovered during these investigations. While every effort has been made, within the limits of the project budget, time and present-day insight, to determine overall ground conditions on this site, poorer sub-areas may have been missed.

VGIconsult Projects (Pty.) Ltd. P.O. BOX 604 FOURWAYS 2055 TEL : (011) 469 0854 FAX : (011) 469 0961 FAX : 0866892847 e-mail: [email protected]

TABLES SUMMARISED BOREHOLE INFORMATION AND INHERENT HAZARD CHARACTERISATION

TABLE 1

7148-01 1545 7148-02 1545 7148-03 1545 7148-04 1546 7148-05 1549 7148-06 1551 7148-07 1543 7148-08 1542 7148-10 1541 7148-11 1539 7148-24 1541

BH No. (Collar Elev. m AMSL)

0-21

0-2

0-6

-

0-2

0-15

0-6

0-18

0-10

0-40

-

-

-

-

-

-

-

-

-

-

Colluvium

0-9

Fines dominant

-

Ferroan Soils -

-

-

-

-

-

-

-

-

-

-

-

10-25

18-42

26-30

36-41

-

-

6-9, 16-21

-

22-26

-

Manganiferrous Soils

Blanketing Layer (m) – (m) Chert Dolomite Residuum Residuum Residual Syenite -

-

-

-

-

-

-

-

-

-

-

Highly weathered dolomite 40-48

25-27

48-49

6-26

15-36, 41-46

2-12

0-9

21-23

2-14

21-22

9-15

15-24 1530 26-29 1524 14-20 1531 23-29 1523 9-15 1540 12-18 1539 46-52 1497 30-46 1512 49-55 1492 27-30 1512 48-54 1493

Dolomite Bedrock (m) – (m) (mAMSL)

TABLE 1: BOREHOLE DATA AND DOLOMITE INHERENT HAZARD CHARACTERISATION

Dry

Dry

Dry

Dry

Dry

Dry

Dry

Dry

Dry

Dry

Dry

Ground-water Rest Level (m) (m AMSL) -

10-30

42-55

26-29

36-52

-

-

9-29

-

22-29

-

(m)–(m)

Air & Sample Losses

-

-

44-48

-

-

-

-

9-16

-

-

-

(m)–(m)

Cavity

MEDIUM

MEDIUM

HIGH

MEDIUMHIGH

MEDIUMHIGH HIGH

MEDIUM

MEDIUM

HIGH

HIGH

HIGH

MEDIUM

MEDIUM

HIGH

HIGH

HIGH

HIGH

MEDIUMHIGH

MEDIUMHIGH HIGH

MEDIUM

MEDIUM

Subsidence Sinkhole Formation Formation

Ingress Water

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

Subsidence Formation

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

LOW

Sinkhole Formation

Groundwater Drawdown

Hazard Characterisation

FIGURES LOCALITY PLAN TOPOGRAPHICAL SHEET LEGEND SITE LAYOUT WITH GROUND ELEVATION CONTOURS REGIONAL GEOLOGY GEOLOGY LEGEND REGIONAL GEOHYDROLOGY

FIGURE 1 FIGURE 1A FIGURE 2 FIGURE 3 FIGURE 3A FIGURE 4

FIGURE 1 27°23'0"E

27°23'30"E

27°24'0"E

27°24'30"E

27°25'0"E

Bank

. !

Welverdiend ! . Carletonville

26°21'30"S

26°21'30"S

. !

Fochville

26°23'30"S

26°23'30"S

26°23'0"S

26°23'0"S

26°22'30"S

26°22'30"S

26°22'0"S

26°22'0"S

. !

27°23'0"E

27°23'30"E

27°24'0"E

27°24'30"E

μ

27°25'0"E

0

0.1 0.2

0.4

0.6

0.8 Kilometres

2627AD CARLETONVILLE 1:50 000

Coordinate System: LO27 Projection: Transverse Mercator Datum: Hartebeesthoek 1994 False Easting: 0.0000 False Northing: 0.0000 Central Meridian: 27.0000 Scale Factor: 1.0000 Latitude Of Origin: 0.0000 Units: Metres

1 233

Carletonville Ext 4

LIGH T POLE

SUB DIVISION NR. ID: CARLTONVILLE

eet

LIGH T POLE

SAM5

LIGH T POLE

PIP E LI NE MA RK ER

235 2

2480

FARMS

39700

SUBURBS

STANDS

39750

GROUND MOVEMENT INCIDENTS: SINKHOLES

GROUND ELEVATION CONTOURS (mAMSL)

ROADS

LEGEND

ND BE

-2918350

-2918400

-2918450

0

23 3

2332

Y -39750

IL=1540.109

235 3 LIGH T POLE

39800

FIRE HYDRANT

2271

SAM6

39850

LIGH T POLE

39850

39900

SAM7

bell Blue

Road

8m x 4m DIA, 7m DEEP

LIGH T POLE

2273

BLYVOORUITZICHTSUB DIVISION NR. 00032 ID: T0IQ00000000011600032

2270

235 4

2333

0

9 23 2

ND BE

°

±

°

45

-2918500

2328 R501

1/4

GV

P5

P

GV EXIS

-2918550

2355

39800

D ROA

11

3

CULVERT

ND BE

AV

2269

2°

2351

1/

P4

Pro pos ed

00m m

15 4

39900

22 7 5

ell Ro Blueb

39950

0

ad

2276

lace os P Cosm

39950

LIGH T POLE

10

20

30

2277

SAM4

40000

Y -40000

0 15 5

22 7 2356

22

P3

GATE

PIP E

P6 ND BE

ite Str Dolom WATER CHAMBER

7

-2918600

2278

40

40000

50 metres

5

8.428 IL=154

2279 -2918350 -2918400 -2918450 -2918500

2 6

15 5

11 1/4° BEND HOLE

E GAT

39750

SINK

P2

2298

-2918550

154 5 E

ROA D

CL 16d ia H DPE

BLU EB E LL

°

eet

E LIN

GA TE

90

ite Str Dolom AD

2 23

SV

2 23

PIP STOS AS BE TING EXIS

GA TE

2350

R

5 232

CHAMBE

E GAT E GAT

2299 LL RO BLUEBE

4 227

E PE PIP dia HD CL 16

2324 IL=1547.983

E GAT

2300 WATER CHAMBER

2323 WATER

2 232 -2918600

2321

GV

2301

mm d 300 Propose

2302 E EGAT GAT

39700

P1

2303 GEOTECHNICAL

page type

A3

VGI7148

MAY 2017

date

FIGURE 2

Drawing number

designed

1:1 100

scale

checked

drawn

ref.no.VGI7148

N.T.

AR.G.

N.T.

SITE LAYOUT WITH GROUND ELEVATION CONTOURS

drawing title

Project Number

VGI7148: S19: WATER PIPELINE REALIGNMENT BLUEBELL ROAD, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION

service

discipline

2 MULBERRY HILL OFFICE PARK BROADACRES DRIVE DAINFERN VALLEY PO BOX 604 FOURWAYS 2055 TEL: (011) 469 0854 FAX: (011) 469 0961 E-mail: [email protected]

VGIconsult

consultant

cad file name

professional registration no.:

date:

name:

certified as-built drawings as per Centralised Drawing Archive AS-BUILT DRAWING REQUIREMENTS

as-built drawings

D.P.W.

False Northing = 0° Scale Factor = 1 Datum = WGS 84

AMENDMENT

Transverse Mercator Central Meridian = 27° False Easting = 0°

co-ordinate system

No. DATE

-2906000

-2911000

-2916000

-2921000

-2926000

-2931000

26000

AREA OF INVESTIGATION

LEGEND

±

26000

31000

31000

36000

AREA OF INVESTIGATION

36000

41000

41000

46000

46000

51000

0

51000

1 000

2 000

3 000

4 000

56000

5 000 metres

56000 -2906000 -2911000 -2916000 -2921000 -2926000 -2931000

GEOTECHNICAL

page type

A3

VGI7148

designed

JUNE 2017

FIGURE 3

Drawing number

checked

drawn

1:100 000

scale date

ref.no.VGI7148

N.T.

AR.G.

N.T.

REGIONAL GEOLOGY (REF.: MAP 2626 WEST RAND 1:250 000 GEOLOGICAL SERIES)

drawing title

Project Number

VGI7148: S19: WATER PIPELINE REALIGNMENT BLUEBELL ROAD, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION

service

discipline

2 MULBERRY HILL OFFICE PARK BROADACRES DRIVE DAINFERN VALLEY PO BOX 604 FOURWAYS 2055 TEL: (011) 469 0854 FAX: (011) 469 0961 E-mail: [email protected]

VGIconsult

consultant

cad file name

professional registration no.:

date:

name:

certified as-built drawings as per Centralised Drawing Archive AS-BUILT DRAWING REQUIREMENTS

as-built drawings

D.P.W.

False Northing = 0° Scale Factor = 1 Datum = WGS 84

AMENDMENT

Transverse Mercator Central Meridian = 27° False Easting = 0°

co-ordinate system

No. DATE

name:

D.P.W.

GEOTECHNICAL

page type

A3

VGI7148

checked

scale date

FIGURE 3A

Drawing number

JUNE 2017

designed drawn

ref.no.VGI7148

N.T.

AR.G.

N.T.

GEOLOGY LEGEND (REF.: MAP 2626 WEST RAND 1:250 000 GEOLOGICAL SERIES)

drawing title

Project Number

VGI7148: S19: WATER PIPELINE REALIGNMENT BLUEBELL ROAD, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION

service

discipline

2 MULBERRY HILL OFFICE PARK BROADACRES DRIVE DAINFERN VALLEY PO BOX 604 FOURWAYS 2055 TEL: (011) 469 0854 FAX: (011) 469 0961 E-mail: [email protected]

VGIconsult

consultant

cad file name

professional registration no.:

date:

AMENDMENT

certified as-built drawings as per Centralised Drawing Archive AS-BUILT DRAWING REQUIREMENTS

as-built drawings

co-ordinate system

No. DATE

-2906000

-2916000

26000

C23K

C23G

C23G

±

26000

R501

C23F

it

36000

46000

it

43500

1:200 000

u pr ps

SEWERAGE WORKS

LARGE RESERVOIR

DAM

INLAND WATER AREAS

41000

43500

1:50 000

26000

26000

R501

Lo

ru sp op

R501

it

46000

R41

Loop spru it

41000

38500

it

43500

1:200 000

u pr ps

SEWERAGE WORKS

LARGE RESERVOIR

DAM

INLAND WATER AREAS

41000

43500

1:50 000

DOLOMITE GROUNDWATER RESOURCE UNITS (GRU)

LEGEND

46000

GROUNDWATER RESOURCE UNITS (GRU)

38500

36000

o Lo

GROUNDWATER MANAGEMENT AREAS (WMA)

LEGEND

GROUNDWATER MANAGEMENT AREAS (WMA)

2 N1

Upper Vaal

4 N1

00 11

m m 60 10

Oberholzer

m 00 13

m 40 13

0 114

m

R501

OBERHOLZER OWL: 1469m AMSL

DOLOMITE GROUNDWATER

60 ) 15 469 (1

1550 ELEV: (1469) OWL: 81

C2N0109

! (

PH20

! (

JI6

38500

! (

C2N0204

C2N0008

! (

RW56

C2N0001

! (

RGW1

41000

NGIS HYDSTRA: DISCONTINUED

1:50 000

NGIS HYDSTRA: STATUS UNKNOWN

43500

1:24 000

! (

NGIS HYDSTRA: IN USE

0m 90

980m

! ( ! (

LEGEND

NATIONAL GROUNDWATER INFORMATION SYSTEM

! (

C2N0198

38500

41000

1220

5 ELEV: 155 9) (146 OWL: 86

1540 ELEV: 69) 71 (14 OWL: ELEV: 1445 OWL: 76 (1469)

OWL: 61 (1469)

OBERHOLZER ELEV: 1530

m

25 V: 15(1469) ELE AREAS MANAGEMENT L: 56 OW

GROUNDWATER CONTOURS

DOLOMITE GROUNDWATER COMPARTMENTS

m 1180

: EV EL : 91 L OW

m 60 12

41000

GROUNDWATER CONTOURS

LEGEND

DOLOMITE GROUNDWATER MANAGEMENT AREAS AND DWA REPORTS

m 80 13

38500

C2N0110

ELEV: 1510 OWL: 41 (1469)

14 20 m

36000

0

38500

o Lo

C23D

QUATERNARY CATCHMENTS

-2906000

LEGEND

R41

Loop spru it

46000

DOLOMITE GROUNDWATER MANAGEMENT UNITS (GMU)

LEGEND

41000

QUATERNARY CATCHMENTS

Lo

ru sp op

C23J

R501

C23E

0

GROUNDWATER MANAGEMENT UNITS (GMU)

38500

2 N1

4 N1

-2906000

-2916000

E OW LEV: L: 46 1515 (146 9) EL OW EV: 15 L: 51 20 (146 9)

36000

-2906000 -2916000 -2926000 -2936000

-2926000

-2936000

-2916000

-2918500

-2921000

-2918500 -2916000

OWELE L: V: 1 66 53 (14 5 69 ) 94 0m

-2916000

-2926000 -2936000 -2916000

-2926000 -2936000 -2916000

-2918500

R50 -2918500

ruit -2921000

00 R5

R50

-2918500

38500

41000

43500

-2918500

00 R5 -2918500

p sp ruit -2921000

alko p sp -2921000

Kra alko

-2918500

Kra

-2921000

0 -2921000

-2916000

R50

-2916000

00 R5

00 R5

00 R5

AMENDMENT

name:

GEOTECHNICAL

A2

page type

VGI7148 S19

S19 JUNE 2017

FIGURE 4

Drawing number

date

scale

ref.no. VGI7148

checked

drawn

designed

N.T.

AR.G.

N.T.

REGIONAL GEOHYDROLOGY (REF.: MAP 2627 BD GRASMERE 1:25 000)

drawing title

Project Number

VGI7148: S19: WATER PIPELINE REALIGNMENT BLUEBELL ROAD, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION

service

discipline

2 MULBERRY HILL OFFICE PARK BROADACRES DRIVE DAINFERN VALLEY PO BOX 604 FOURWAYS 2055 TEL: (011) 469 0854 FAX: (011) 469 0961 E-mail: [email protected]

VGIconsult

consultant

cad file name

professional registration no.:

date:

False Northing = 0° Scale Factor = 1 Datum = WGS 84

D.P.W.

certified as-built drawings as per Centralised Drawing Archive AS-BUILT DRAWING REQUIREMENTS

as-built drawings

Transverse Mercator Central Meridian = 27° False Easting = 0°

RIVERS

AREA OF INVESTIGATION

GENERAL LEGEND

co-ordinate system

No. DATE

DRAWINGS RESIDUAL GRAVITY, BOREHOLE POSITIONS AND DOLOMITE HAZARD VGI7148S19/1 ZONATION

! (

7148-11 10-23 NSR LDDR R@23

ND

4/7//1

! (

39750

Dolo

VGI7148 S19 SINKHOLE

mite

Stre

IL=1540.109

LIGHT POLE

7148-07

! ( R@15

CARLETONVILLE REGIONAL RESIDUAL GRAVITY (mGals)

RESIDUAL GRAVITY (mGals)

ROADS

VGI7148 S19 PIPELINE

! (

PIPE LINE MARKER

! (

7148-08 R@6? or 30

! (

LIGHT POLE

7148-24 R@48

2352

53 23

0. 0

Y -39750

VGIconsult DATABASE BOREHOLES

t

! (

LEGEND

SAM5

JI 54

FARMS

SUBURBS

STANDS

39750

GROUND MOVEMENT INCIDENTS: SINKHOLES

39800

FIRE HYDRANT

.4 +0

.3 +0

39800

7148-01 R@9

! (

SAM6

Carletonville Ext 4

39850

2272

! (

Blue

o ad

5/6(3)//1

39850

BLYVOORUITZICHTSUB DIVISION NR. 00032 ID: T0IQ00000000011600032

bell R

7148-02 22-26 Cavity R@21-22&26

LIGHT POLE

LIGHT POLE

SUB DIVISION NR. ID: CARLTONVILLE

2273

2274

! (

7148-04 9-16 Cavity 16-21 NSR R@23

SAM7

0 39900

! ( 7148-21

. 1

B

0 . 2

l Road luebel

7148-09 ( 7148-17 !

( ! ! ! ( ( 7148-18

7148-20

0

! (

6/7(5)//1 7148-19

7148-03 ( R@2 !

39900

.2 +1

39950

+1.2 39950

0

! (

7148-05 R@0

.0 +1

10

.8 +0 20

LIGHT POLE

30

SAM4

40000

2 0 .

40

R@2

! ( 7148-06

Cosm

40000

50 metres

.9 +0

39700

! (

31

7148-10 Cavity 44-48 R@49

LIGHT POLE

23

30

23

+0 .1

+0 .2

23

-2918400

-2918450

P6 ND

-2918500

+1.1

2332

+0 .2

11 1/4° BEND

-0. 2

BE

BE

-2918550

0.0

° 45

±

+0.1

+0 .3

Y -40000

-0 .1

P5

Stree

-2918600

+0. 5

os Pla

ce

+0.9

2

4 235

+0 .6

+1.2

29

ND

E

mite

+0 .3

+0.9

2355

+0 .7

+0 .9

2328 R501

BE

JI54

D ROA

° 1/4 11

GV

CL

PIP

39700

1 0 .

+1.1 +1.0 0

+1.0 IL=1548.428

-2918400 -2918450 -2918500

+0.9 .

0

-

+

+0.6 0

ND

AV 1E - 0 .B

2°

P4

Pro pos ed

300 mm

AD

16d ia H DPE

BLU EBE LL R O

GA TE

° 90

Dolo

+0.8

- 0 . 1

+

+0. 4

1/

GATE

GA TE

CULVERT

-2918550

2356

22

27

+

WATER CHAMBER

P3

E GAT

+0.4 E HOL

6

-2918600

+1.0 SINK

P2

23 E

2 23 E LIN S PIP

5 O BEST G AS

+0.7 AD

+0.8 LL RO BLUEBE

9 +0. SV

PIPE

232

HDPE

2324 TIN EXIS

+1.0

dia CL 16

2298 E GAT E GAT

+1.1

IL=1547.983

2299 WATER CHAMBER

E GAT

2300

300mm

2323 R

2 CHAMBE

2301 WATER

232

2321

ed Propos

2302

0 +1.

.8 +0

7 +0.

et

+0.5

+0 .5

GEOTECHNICAL

A2

page type

VGI7148

MAY 2017

date

N.T.

AR.G.

N.T.

DRAWING VGI7148 S19/01

Drawing number

drawn

1:700

scale

checked

designed

ref.no. VGI7148

RESIDUAL GRAVITY WITH BOREHOLE POSITIONS AND DOLOMITE HAZARD ZONATION

drawing title

Project Number

VGI7148: S19: WATER PIPELINE REALIGNMENT BLUEBELL ROAD, CARLETONVILLE: DOLOMITE STABILITY INVESTIGATION

service

discipline

2 MULBERRY HILL OFFICE PARK BROADACRES DRIVE DAINFERN VALLEY PO BOX 604 FOURWAYS 2055 TEL: (011) 469 0854 FAX: (011) 469 0961 E-mail: [email protected]

VGIconsult

consultant

cad file name

professional registration no.:

date:

name:

certified as-built drawings as per Centralised Drawing Archive AS-BUILT DRAWING REQUIREMENTS

as-built drawings

D.P.W.

False Northing = 0° Scale Factor = 1 Datum = WGS 84

AMENDMENT

Transverse Mercator Central Meridian = 27° False Easting = 0°

co-ordinate system

No. DATE

APPENDICES BOREHOLE PROFILES APPENDIX 1

APPENDIX 1 BOREHOLE PROFILES

3.16

3.08

3.11

3.06

3.02

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES DATE : 23/06/17 14:53 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/23 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-01

ELEVATION : 1545 m AMSL X-COORD : 2918504 Y-COORD : -39831

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports no air or sample loss.

6) Water added between 8 m to 10 m and 13 m to 16 m.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/23

2) No groundwater intercepted.

NOTES

Subangular blue grey unweathered hard rock DOLOMITE.

Subangular brown grey highly weathered soft rock DOLOMITE.

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

3.00

24.00

18.00

9.00

0.00

S19

1) Driller reports solid conditions between 18 m to 24 m.

20

15

10

5

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-01 Sheet 1 of 1

2.46

2.33

1.45

1.41

1.27

1.20

1.23

1.16

1.04

0.38

0.34

0.36

0.32

0.21

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

1525

1530

1535

1540

0.18

0.23

0.26

0.22

MORAD BLUE BELL

REDUCED LEVEL

1520

1525

1530

1535

1540

Brown silty CLAY with minor angular translucent blue grey highly weathered chert fragments; CHERT RESIDUUM

REDUCED LEVEL

12 3 Air SampleHammer Penetr return recov rate time min:s/m

2) No groundwater intercepted.

1) Driller reports solid conditions between 26 m to 29 m.

NOTES

S19

12 3 Air SampleHammer Penetr return recov rate time min:s/m

3.04

3.06

3.02

0.08

0.03

0.01

0.01

1.02

0.24

0.26

0.31

0.23

0.28

0.30

0.32

0.34

0.28

0.23

0.18

0.20

0.27

25

20

15

29.00

26.00

22.00

21.00

interpreted

as

NO SAMPLE RETURN; interpreted as hard rock dolomite

NO SAMPLE RETURN; dolomite residuum

Subangular brown grey highly weathered soft rock DOLOMITE.

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

DATE : 23/06/17 14:53 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/23 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-02

ELEVATION : 1545 m AMSL X-COORD : 2918503 Y-COORD : -39864

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports total air and sample loss from 22 m to 29 m.

6) No water added.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

12.00

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-02 Sheet 2 of 2

0.25

0.31

10

0.00

S19

MORAD BLUE BELL

3) Groundwater rest level recorded as dry on 2017/05/23

5

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-02 Sheet 1 of 2

0.39

0.33

0.36

0.30

0.27

0.23

MORAD BLUE BELL

3.14

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES DATE : 23/06/17 14:53 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/23 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-03

ELEVATION : 1546 m AMSL X-COORD : 2918493 Y-COORD : -39908

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports no air or sample loss.

6) Water added between 1 m to 4 m, 5 m to 7 m and 8 m to 9 m.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/23

2) No groundwater intercepted.

NOTES

Subangular blue grey unweathered hard rock DOLOMITE.

Subangular brown grey highly weathered soft rock DOLOMITE.

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

3.18

20.00

14.00

2.00

0.00

S19

1) Driller reports solid conditions between 14 m to 20 m.

20

15

10

5

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-03 Sheet 1 of 1

3.11

3.07

3.05

3.02

2.46

2.31

1.07

1.05

1.13

1.07

1.05

2.24

2.16

1.42

1.48

1.36

0.40

0.37

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

1530

1535

1540

1545

MORAD BLUE BELL

REDUCED LEVEL

1520

1525

1530

1535

1540

1545

12 3 Air SampleHammer Penetr return recov rate time min:s/m

3.05

3.13

3.08

3.11

3.09

3.06

2.38

1.15

0.38

0.23

0.07

0.06

0.01

0.02

0.03

0.01

0.02

0.01

0.01

0.02

0.31

0.27

0.39

0.58

0.42

0.38

0.45

0.40

0.36

MORAD BLUE BELL

25

20

15

10

5

Scale 1:150

29.00

23.00

21.00

16.00

9.00

6.00

0.00

S19

interpreted

as

NO SAMPLE RETURN; interpreted as hard rock dolomite

NO SAMPLE RETURN; interpreted as soft rock dolomite

NO SAMPLE RETURN; dolomite residuum

CAVITY

Brown silty CLAY with minor angular translucent blue grey highly weathered chert fragments and black silt ( WAD); DOLOMITE RESIDUUM

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-04 Sheet 1 of 2

12 3 Air SampleHammer Penetr return recov rate time min:s/m

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

REDUCED LEVEL

MORAD BLUE BELL

S19

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/23 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-04

ELEVATION : 1546 m AMSL X-COORD : 2918490 Y-COORD : -39915

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports medium air loss between 23 m to 28 m, total air loss between 9 m to 23 m, 28 m to 29 m and total sample loss from 9 m to 29 m

6) Water added between 1 m to 3 m

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/23

2) No groundwater intercepted.

1) Driller reports solid conditions between 23 m to 29 m.

NOTES

JOB NUMBER: 7148

HOLE No: 7148-04 Sheet 2 of 2

9.00

10

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/23 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-05

ELEVATION : 1549 m AMSL X-COORD : 2918480 Y-COORD : -39962

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports no air or sample loss.

6) Water added between 0 m to 3 m, 4 m to 6 m and 11 m to 15 m.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/23

2) No groundwater intercepted.

1) Driller reports solid conditions between 9 m to 15 m.

NOTES

15

10

5

Scale 1:150

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

3.03

3.08

3.14

3.09

3.06 1535

3.11

3.09 15.00

3.06

15

2.34

3.11

2.27

2.16

3.05

3.08 1540

1.49 Subangular blue grey unweathered hard rock DOLOMITE.

1.37

2.56

3.02

1.22

2.31

1.19

2.24

2.17

1.15 1545

0.49

0.46

1.48

5

1550

1.08

Subangular brown grey highly weathered soft rock DOLOMITE. 1.06

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

1535

1540

1545

0.00

S19

MORAD BLUE BELL

1.34

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-05 Sheet 1 of 1

1.26

1.18

1.07

MORAD BLUE BELL

S19

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT dot.PLOT 5006 J&W

HOLE No: 7148-06

ELEVATION : 1551 m AMSL X-COORD : 2918476 Y-COORD : -39988

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports no air or sample loss.

6) Water added between 1 m to 3 m, 4 m to 6 m and 7 m to 11 m

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/23

2) No groundwater intercepted.

1) Driller reports solid conditions between 12 m to 18 m.

NOTES

Subangular blue grey unweathered hard rock DOLOMITE.

Subangular brown grey highly weathered soft rock DOLOMITE.

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/23 DATE : 2017/05/31

18.00

12.00

2.00

0.00

JOB NUMBER: 7148

HOLE No: 7148-06 Sheet 1 of 1

REDUCED LEVEL

1510

1515

1520

1525

1530

1535

1540

3.09

3.00

3.05

3.07

3.11

3.01

2.43

2.31

1.56

1.32

1.18

0.05

0.07

0.11

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

1495

1500

1505

0.09

0.06

1.39

1.41

1.38

50

45

40

35

52.00

46.00

41.00

36.00

interpreted

as

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/22

2) No groundwater intercepted.

1) Driller reports solid conditions between 46 m to 52 m.

NOTES

NO SAMPLE RETURN; interpreted as hard rock dolomite

NO SAMPLE RETURN; interpreted as soft rock dolomite

NO SAMPLE RETURN; dolomite residuum

S19

1 21.38 3 Air SampleHammer Penetr return recov rate time min:s/m

1.26

1.21

1.08

1.17

1.06

0.49

0.55

0.52

30

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/22 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-07

ELEVATION : 1543 m AMSL X-COORD : 2918503 Y-COORD : -39785

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports medium air loss from 36 m to 52 m and total sample loss from 36 m to 52 m

6) Water added between 18 m to 22 m, 23 m to 26 m, 27 m to 33 m, 34 m to 36 m, 41 m to 46 m, 47 m to 48 m and 50 m to 51 m.

Subangular brown grey highly weathered soft rock DOLOMITE.

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-07 Sheet 2 of 2

5) Oberholzer Groundwater Compartment

15.00

0.00

S19

MORAD BLUE BELL

1.3

25

20

15

10

5

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-07 Sheet 1 of 2

1.16

1.27

1.19

1.23

1.17

1.13

1.07

1.10

1.03

0.40

0.42

0.45

0.39

0.43

0.41

0.37

0.35

0.28

0.30

0.31

0.34

0.26

0.22

0.18

MORAD BLUE BELL

REDUCED LEVEL

1510

1515

1520

1525

1530

1535

1540

1 21.34 3 Air SampleHammer Penetr return recov rate time min:s/m

1.29

1.28

1.16

1.02

0.38

0.31

1.09

1.53

1.49

1.4

1.39

1.47

1.55

1.40

1.32

1.54

1.41

1.34

1.30

1.19

1.36

1.34

1.30

1.09

1.20

1.26

1.12

0.31

0.39

0.36

0.19

0.13

0.09

MORAD BLUE BELL

30

25

20

15

10

5

Scale 1:150

30.00

29.00

26.00

6.00

0.00

S19

interpreted

as

Brown silty CLAY with minor subangular brown grey highly weathered dolomite fragments and black silt ( WAD); DOLOMITE RESIDUUM

NO SAMPLE RETURN; dolomite residuum

Brown silty CLAY with minor angular translucent blue grey highly weathered chert fragments and black silt ( WAD); DOLOMITE RESIDUUM

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-08 Sheet 1 of 2

12 3 Air SampleHammer Penetr return recov rate time min:s/m

3.08

3.02

3.06

3.11

3.09

3.10

2.39

2.35

2.25

1.33

45

40

35

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

REDUCED LEVEL

1500

1505

1.38

1.19

1.34

MORAD BLUE BELL

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT dot.PLOT 5006 J&W

HOLE No: 7148-08

ELEVATION : 1542 m AMSL X-COORD : 2918495 Y-COORD : -39756

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports medium air loss between 26 m to 29 m and total sample loss between 26 m to 29 m

6) Water added between 0 m to 3 m and 14 m to 21 m.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/19

2) No groundwater intercepted.

1) Driller reports solid conditions between 40 m to 46 m.

NOTES

Subangular blue grey unweathered hard rock DOLOMITE.

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/19 DATE : 2017/05/31

46.00

40.00

S19

Subangular brown grey highly weathered soft rock DOLOMITE.

JOB NUMBER: 7148

HOLE No: 7148-08 Sheet 2 of 2

REDUCED LEVEL

1510

1515

1520

1525

1530

1535

1540

1 20.39 3 Air SampleHammer Penetr return recov rate time min:s/m

0.46

0.51

1.16

1.36

1.34

1.22

1.36

1.30

1.26

1.32

1.27

1.20

1.18

1.16

1.03

1.07

1.09

1.12

1.16

1.10

1.07

0.52

0.48

0.46

0.34

0.40

0.41

0.39

0.32

0.31

0.25

0.28

0.26

MORAD BLUE BELL

30

25

20

15

10

5

Scale 1:150

18.00

3.00

0.00

S19

Brown silty CLAY with minor angular translucent blue grey highly weathered chert fragments and black silt ( WAD); DOLOMITE RESIDUUM

Brown silty CLAY with minor angular translucent blue grey highly weathered chert fragments; CHERT RESIDUUM

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-10 Sheet 1 of 2

3.04

3.08

3.11

3.07

3.00

3.02

1.16

0.01

0.03

0.01

0.01

0.05

0.07

0.43

0.45

0.42

0.37

0.35

0.48

0.52

55

50

45

40

35

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

1490

1495

1500

1505

0.47

0.39

MORAD BLUE BELL

interpreted

as

S19

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT dot.PLOT 5006 J&W

HOLE No: 7148-10

ELEVATION : 1541 m AMSL X-COORD : 2918483 Y-COORD : -39716

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports medium air loss from 48 m to 49 m, total air loss between 42 m to 48 m, 49 m to 55 m and total sample loss from 42 m to 55 m

6) Water added between 7 m to 10 m, 15 m to 17 m, 19 m to 24 m, 30 m to 31 m, 32 m to 33 m, 34 m to 36 m, 37 m to 40 m, 48 m to 51 m and 53 m to 55 m.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

3) Groundwater rest level recorded as dry on 2017/05/22

2) No groundwater intercepted.

1) Driller reports solid conditions between 49 m to 55 m.

NOTES

NO SAMPLE RETURN; interpreted as hard rock dolomite

NO SAMPLE RETURN; interpreted as soft rock dolomite

CAVITY

NO SAMPLE RETURN; dolomite residuum

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/22 DATE : 2017/05/31

55.00

49.00

48.00

44.00

42.00

JOB NUMBER: 7148

HOLE No: 7148-10 Sheet 2 of 2

REDUCED LEVEL

1510

1515

1520

1525

1530

1535

NO SAMPLE RETURN; dolomite residuum

interpreted

as

REDUCED LEVEL

12 3 Air SampleHammer Penetr return recov rate time min:s/m

2) No groundwater intercepted.

1) Driller reports no solid conditions, rods getting stuck.

NOTES

S19

12 3 Air SampleHammer Penetr return recov rate time min:s/m

1.15

1.33

0.59

0.41

0.19

1.15

1.07

0.30

0.15

0.17

0.53

0.36

0.11

0.15

0.10

0.12

0.16

0.13

0.10

0.15

2.05

1.31

30

25

20

15

30.00

27.00

25.00

23.00

interpreted

as

NO SAMPLE RETURN; interpreted as soft rock dolomite

NO SAMPLE RETURN; dolomite residuum

NO SAMPLE RETURN; interpreted as soft rock dolomite

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/29 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-11

ELEVATION : 1539 m AMSL X-COORD : 2918441 Y-COORD : -39699

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports slight air loss between 18 m to 20 m, 22 m to 23 m, 24 m to 25 m, 26 m to 30 m, medium air loss from 10 m to 18 m, 20 m to 22 m, 23 m to 24 m, 25 m to 26 m and total sample loss from 10 m to 30 m

6) Water added between 0 m to 2 m and 3 m to 6m

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL 10.00

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-11 Sheet 2 of 2

1.27

1.23

10

0.00

S19

MORAD BLUE BELL

3) Groundwater rest level recorded as dry on 2017/05/29

5

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-11 Sheet 1 of 2

1.10

1.02

0.50

0.52

0.47

0.41

MORAD BLUE BELL

REDUCED LEVEL

1510

1515

1520

1525

1530

1535

1540

3.07

3.01

3.10

3.09

3.08

3.11

2.07

2.03

1.49

1.46

1.53

1.46

2.06

2.01

1.56

1.43

1.45

1.44

1.47

12 3 REDUCED Penetr Air SampleHammer LEVEL return recov rate time min:s/m

1490

1495

1500

1505

1.52

2.03

50

45

40

35

54.00

48.00

40.00

2) No groundwater intercepted.

1) Driller reports solid conditions between 48 m to 54 m.

NOTES

Subangular blue grey unweathered hard rock DOLOMITE.

Subangular brown grey highly weathered soft rock DOLOMITE.

S19

1 22.03 3 Air SampleHammer Penetr return recov rate time min:s/m

2.12

2.09

2.00

2.26

2.17

2.03

2.05

1.57

2.00

2.41

30

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : J.K. DEVELOPMENTS MACHINE : THOR 5000 DRILLED BY : J.G MALULEKE PROFILED BY : J.MEINTJES

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT

INCLINATION : 90 DEGREES DIAM : 165mm DATE : 2017/05/29 DATE : 2017/05/31

dot.PLOT 5006 J&W

HOLE No: 7148-24

ELEVATION : 1541 m AMSL X-COORD : 2918486 Y-COORD : -39731

8) Projection Information: CM 27 degrees, Transverse Mercator, WGS 84

7) Driller reports no air or sample loss

6) Water added between 21 m to 40 m.

5) Oberholzer Groundwater Compartment

4) Original Dolomite Aquifer Groundwater Level (OWL) 1469m AMSL

Brown silty CLAY with minor angular translucent blue grey highly weathered chert fragments; CHERT RESIDUUM

Reddish brown clayey SAND with minor angular white highly weathered chert gravel; CHERT RESIDUUM

JOB NUMBER: 7148

HOLE No: 7148-24 Sheet 2 of 2

2.08

6.00

0.00

S19

MORAD BLUE BELL

3) Groundwater rest level recorded as dry on 2017/05/29

25

20

15

10

5

Scale 1:150

JOB NUMBER: 7148

HOLE No: 7148-24 Sheet 1 of 2

2.48

2.05

2.18

2.01

2.03

2.07

2.00

1.53

1.42

1.35

1.43

1.07

2.03

1.32

1.18

0.47

1.05

0.59

0.53

0.36

0.40

0.38

MORAD BLUE BELL

D055 DBB

TYPE SET BY : J.MEINTJES SETUP FILE : SETUP.SET

CONTRACTOR : MACHINE : DRILLED BY : PROFILED BY :

MORAD BLUE BELL

{SA09} {SA13} {SA22}

CLAYEY

DOLOMITE

WAD

DATE : 23/06/17 14:54 TEXT : ..C:\DOTFILES\201706~1.TXT

dot.PLOT 5006 J&W

SUMMARY OF SYMBOLS

LEGEND

{SA08}

CLAY

ELEVATION : X-COORD : Y-COORD :

{SA07}

SILTY

INCLINATION : DIAM : DATE : DATE :

{SA04}

S19

SAND

JOB NUMBER: 7148

Sheet 1 of 1

LEGEND