FOR - GCS...Compiled For: Assmang Iron Ore Compiled By: K.H. Vermaak(M.Sc.) GPT Reference: Kum-09-403 Version: Final Version 1.0 Date: June 2010 Distribution List (Current Version):

Compiled by:

Geo Pollution Technologies � Gauteng (Pty) Ltd

81 Rauch Avenue

Georgeville

0184

P.O. Box 38384

Garsfontein East

0060

Tel: +27 (0)12 804 8120

Fax: +27 (0)12 804 8140

EVALUATION OF THE HYDROGEOLOGICAL DATA

AT KHUMANI MINE AND THE DEVELOPMENT OF A

GROUNDWATER MANAGEMENT PLAN

FOR

Khumani Iron Ore Mine

KATHU

GPT Reference Number: Kum-09-403

Version: Final Version 1.0

Date: June 2010

Compiled for:

Assmang Ltd Khumani Iron Ore

Hydrogeological Investigation - Khumani Iron Ore Mine

GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD ii

Report Type: Hydrogeological Investigation

Project Title: Evaluation of the Hydrogeological data at Khumani mine and the development of a

groundwater management plan

Site Location: Postmasburg District

Northern Cape Province

Compiled For: Assmang Iron Ore

Compiled By: K.H. Vermaak(M.Sc.)

GPT Reference: Kum-09-403

Version: Final Version 1.0

Date: June 2010

Distribution List (Current Version): Word and PDF on CD to Assmang Khumani Iron ore

Copy of CD at Geo Pollution Technologies

Disclaimer:

The results and conclusions of this report are limited to the Scope of Work agreed between GPT and the Client for whom this

investigation has been conducted. All assumptions made and all information contained within this report and its attachments

depend on the accessibility to and reliability of relevant information, including maps, previous reports and word-of-mouth,

from the Client and Contractors. All work conducted by GPT is done in accordance with the GPT Standard Operating

Procedures. GPT is in the process of obtaining ISO 9001:2008 accreditations.

Copyright:

The copyright in all text and other matter (including the manner of presentation) is the exclusive property of Geo Pollution

Technologies � Gauteng (Pty) Ltd, unless where referenced to external parties. It is a criminal offence to reproduce and/or

use, without written consent, any matter, technical procedure and/or technique contained in this document. This document

must be referenced if any information contained in it is used in any other document or presentation.

Declaration:

I hereby declare:

1. I have no vested interest (present or prospective) in the project that is the subject of this report as well as its

attachments. I have no personal interest with respect to the parties involved in this project.

2. I have no bias with regard to this project or towards the various stakeholders involved in this project.

3. I have not received, nor have I been offered, any significant form of inappropriate reward for compiling this report.

K.H. Vermaak (M.Sc.)


Quality Control:

This report was checked by:

Dr V.d.A Coetsee (D.Sc.)

Professional Natural Scientist (No 400084/89)


Customer Satisfaction:

Feedback regarding the technical quality of this report (i.e. methodology used, results discussed and recommendations

made), as well as other aspects, such as timeouts completion of project and value of services rendered, can be posted onto

GPT�s website at www.gptglobal.com.

http://www.gptglobal.com


GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD iii

EXECUTIVE SUMMARY

Geo Pollution Technologies was tasked to conduct a thorough evaluation of the geohydrological

situation and develop a sound groundwater management plan for the Khumani Iron Ore Mine.

Open-cast mining has been taking place in the vicinity since the mid 1970s at the nearby Kumba Iron

Ore Mine. The depth of the ore in the area has resulted in the mining intersecting the natural water

table. In order for mining to commence below the natural static water levels, large volumes of

groundwater have been abstracted over a long period of time. This prolonged abstraction has

caused large areas to be dewatered. Numerous studies have been undertaken to determine the

extent of the dewatering and its effects on the local aquifers.

As dewatering had occurred before the initiation of mining at Khumani, the aquifers within the

eastern area of the mine property had already been dewatered. Thus, the intersection of the water

table at Khumani will take longer than if no previous abstraction had taken place. Khumani had

therefore not begun abstracting any groundwater at the time of this investigation.

An initial hydrocensus was conducted by Geo Pollution Technologies (hereafter GPT) in the study

area where water levels, coordinates and samples were taken. It was noted that many of the local

farmers had experienced diminished borehole yields. A cation-anion analysis was done on the 30

boreholes strategically chosen in the area. No significant problematic chemical issues were

prevalent. The water quality in the area is within acceptable SANS standards.

Historical Department of Water Affairs (DWA) data were used to determine the extent of the

dewatered area. A proposed monitoring network based on the DWA data was also suggested.

Thereafter, a field verification of the proposed monitoring network was carried out. This included

investigating the suitability of the proposed boreholes for the monitoring network. However, the

majority of DWA data was found to be unsuitable/unreliable or no access could be obtained to enter

the property. The proposed monitoring network which was based on the DWA data was abandoned

due to the questionable integrity of the data.

A new monitoring network was established and additional drilling targets were sited using

geophysics. The monitoring network will monitor the effects of abstraction and water quality. The

data gained from this monitoring network will also act as baseline data for future reference. The

boreholes located on or adjacent to structures will monitor the effect of the structures on the

water levels. It was recommended that a sound groundwater database be established and kept up to

date. This will facilitate easy access to data at all times.

It has become apparent that compartmentalisations of the aquifers by dolerite dykes are in effect in

the project area; these effects should be monitored closely. A north�south striking structure running

through the mine property forms a barrier, and the differences in water levels on either side of the

structure are notable. The permeabilities of the structures forming these compartments are

questionable as faulting and weathering can compromise the compartment-forming properties.

A management plan concerning the water quantity and quality has been set in place based on the

stipulations set out by the draft water licence. The requirements are to be strictly adhered to in

order to ensure appropriate and successful water management. The sharing of data between Kumba

and Khumani is imperative in order to gain a better understanding of the dewatering in the area.


GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD iv

TABLE OF CONTENTS

PAGE

1 INTRODUCTION ................................................................................ 8

2 SCOPE OF WORK ............................................................................... 9

3 METHODOLOGY ............................................................................... 10

3.1 DESK STUDY .............................................................................................. 10

3.2 HYDROCENSUS ........................................................................................... 11

3.3 SAMPLING AND CHEMICAL ANALYSIS .................................................................. 11

3.3.1 Quality assurance .................................................................................... 11

3.4 GEOPHYSICAL SURVEY .................................................................................. 11

3.4.1 Magnetometer ........................................................................................ 12

3.4.2 Electromagnetic method ............................................................................ 12

4 DESCRIPTION OF STUDY AREA ............................................................. 13

4.1 CLIMATE ................................................................................................... 13

4.2 REGIONAL GEOLOGY .................................................................................... 13

4.3 REGIONAL GEOHYDROLOGY ............................................................................ 13

4.3.1 The role and impact of the Gamagara River on the local geohydrology ..................... 14

5 RESULTS OF INVESTIGATION ............................................................... 17

5.1 HYDROCENSUS ........................................................................................... 17

5.2 WATER QUALITY ......................................................................................... 27

5.3 DEPARTMENT OF WATER AFFAIRS (DWA) DATABASE ................................................ 39

5.4 WATER LEVELS ........................................................................................... 39

5.4.1 Water level sections ................................................................................. 40

5.4.2 Historical water levels ............................................................................... 40

5.4.3 Area impacted by dewatering base on DWA data ............................................... 41

6 CONCEPTUAL MODEL ........................................................................ 47

6.1 CONCEPTUAL MODEL BOUNDARIES .................................................................... 47

6.2 GROUNDWATER CONSIDERATION ...................................................................... 48

6.2.1 Hydraulic properties ................................................................................. 48

6.2.2 Discharge/Pumping from the aquifer ............................................................. 48


GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD v

6.2.3 Flow directions ....................................................................................... 48

7 MONITORING NETWORK ..................................................................... 49

7.1 GROUNDWATER MONITORING NETWORKS ............................................................ 49

7.1.1 Source, plume, impact and background monitoring ............................................ 49

7.2 SYSTEM RESPONSE MONITORING NETWORKS ......................................................... 49

8 VERIFICATION OF CONCEPTUAL MODEL .................................................. 51

8.1 GEOPHYSICAL SURVEY .................................................................................. 51

8.1.1 Drilling recommendations ........................................................................... 58

8.2 NEWLY PROPOSED MONITORING NETWORK .......................................................... 58

8.3 WATER LEVELS WITHIN THE MINE BOUNDARY ....................................................... 62

8.4 SURFACE WATER MONITORING ......................................................................... 62

8.4.1 Water quality ......................................................................................... 62

8.4.2 Monitoring ............................................................................................. 62

8.4.3 Method of analysis ................................................................................... 62

8.4.4 Reporting .............................................................................................. 62

8.4.5 Storm water management .......................................................................... 62

8.5 MONITORING FREQUENCY .............................................................................. 62

8.6 MONITORING PARAMETERS ............................................................................. 63

8.6.1 Full analysis ........................................................................................... 63

8.7 INADEQUACIES OF THE MONITORING NETWORK ..................................................... 64

9 GROUNDWATER RELATED ENVIRONMENTAL MANAGEMENT PLAN (EMP) ........... 66

10 CONCLUSIONS AND RECOMMENDATIONS ................................................. 69


GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD vi

LIST OF FIGURES

PAGE

FIGURE 1: LOCALITY MAP ...................................................................................... 15 FIGURE 2: GEOLOGY AT THE PROJECT AREA WITH THE BOREHOLES SAMPLED DURING THE

HYDROCENSUS. ..................................................................................... 16

FIGURE 3: HYDROCENSUS BOREHOLE POSITIONS WITH DEPTH TO WATER LEVEL (MBGL) ............ 18 FIGURE 4: LOCATIONS OF BOREHOLES ON KHUMANI MINE PROPERTY ................................... 26

FIGURE 5: BOREHOLE POSITIONS WHERE SAMPLES WERE COLLECTED ................................... 31 FIGURE 6: STIFF DIAGRAMS FOR MAJOR CATIONS AND ANIONS ........................................... 32

FIGURE 7: STIFF DIAGRAMS FOR MAJOR CATIONS AND ANIONS ........................................... 33 FIGURE 8: DIAGRAM USED IN THE INTERPRETATION OF PIPER DIAGRAMS ............................... 34

FIGURE 9: PIPER DIAGRAM FOR MAJOR CATIONS AND ANIONS. ........................................... 34 FIGURE 10: CONCENTRATIONS OF MAGNESIUM IN THE STUDY AREA ...................................... 35 FIGURE 11: BOX AND WHISKER PLOTS OF CHLORIDE, CALCIUM, AND ALUMINIUM ....................... 36 FIGURE 12: BOX AND WHISKER PLOTS OF SODIUM AND SULPHATE ........................................ 36 FIGURE 13: BOX AND WHISKER PLOTS OF IRON .............................................................. 37

FIGURE 14: BOX AND WHISKER PLOTS OF MAGNESIUM ...................................................... 37 FIGURE 15: BOX AND WHISKER PLOTS OF ELECTRICAL CONDUCTIVITY AND TOTAL DISSOLVED

SOLIDS. .............................................................................................. 38 FIGURE 16: BOX AND WHISKER PLOTS OF NITRATES ......................................................... 38

FIGURE 17: BOX AND WHISKER PLOTS OF PH VALUES OF THE SAMPLES TAKEN ......................... 39 FIGURE 18: CORRELATION GRAPH ............................................................................. 40 FIGURE 19: LOCATION OF WATER LEVEL SECTIONS BASED ON HYDROCENSUS BOREHOLES LOCATED

DURING FEBRUARY AND MARCH. ................................................................. 42

FIGURE 20: WATER LEVEL SECTION ACROSS THE STUDY AREA ............................................. 43 FIGURE 21: WATER LEVEL SECTION ACROSS THE STUDY AREA ............................................. 43 FIGURE 22: WATER LEVEL SECTION ACROSS THE STUDY AREA. ............................................ 43 FIGURE 23: DWA BOREHOLE LOCATIONS � HISTORICAL DATA .............................................. 44 FIGURE 24: DEWATERING IMPACT AREA BASED ON DWEA DATA ........................................... 45

FIGURE 25: MAP SHOWING THE DWA BOREHOLES ON THE DEMARCATED BOUNDARY, REFER TO

APPENDIX C AND E FOR COMPLETE DETAILS .................................................... 46

FIGURE 26: SPRING LOCATED ON MACARTHY FARM ......................................................... 47 FIGURE 27: PROPOSED MONITORING NETWORK BASED ON DWA DATA AND HYDROCENSUS ............ 50

FIGURE 28: LOCATION OF GEOPHYSICAL TRAVERSES ........................................................ 52 FIGURE 29: MACARTHY TRAVERSES 1 AND 2, EM AND MAG ................................................. 53 FIGURE 30: MACARTHY TRAVERSE 3, EM AND MAG .......................................................... 54

FIGURE 31: ROSCOE TRAVERSE 1, EM AND MAG .............................................................. 55 FIGURE 32: ROSCOE TRAVERSE 2 AND 3, MAG ................................................................ 56

FIGURE 33: ROSCOE TRAVERSE 4, MAG........................................................................ 57 FIGURE 34: NEWLY PROPOSED MONITORING NETWORK EXCLUDING HOLES LOCATED DURING

GEOPHYSICS ........................................................................................ 61 FIGURE 35: WATER LEVELS INDICATING POSSIBLE STRUCTURE ............................................ 65


GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD vii

LIST OF TABLES

PAGE

TABLE 1: PARSON ABSTRACTION POINTS AND CORRESPONDING ALLOWED ABSTRACTION

VOLUMES ............................................................................................. 17 TABLE 2: SUMMARY OF THE HYDROCENSUS DATA .......................................................... 19

TABLE 3: BOREHOLES LOCATED ON KHUMANI MINE PROPERTY .......................................... 25 TABLE 4: WATER QUALITY REQUIREMENTS.................................................................. 27

TABLE 5: RESULTS OF MAJOR CATION AND ANION ANALYSES ............................................ 28 TABLE 6: RESULTS OF MAJOR CATION AND ANION ANALYSES ............................................ 29

TABLE 7: RESULTS OF MAJOR CATION AND ANION ANALYSES ............................................ 30 TABLE 8: SUMMARY OF TRAVERSE INFORMATION .......................................................... 51

TABLE 9: LOCATION OF PROPOSED DRILLING SITES FOR MONITORING WELLS ......................... 58 TABLE 10: SUMMARY OF BOREHOLES FOR MONITORING NETWORK ....................................... 59 TABLE 11: WATER LICENCE REQUIREMENTS FOR THE GROUNDWATER QUALITIES ...................... 64 TABLE 12: EMP SUMMARY � WATER QUALITY MANAGEMENT ............................................... 67 TABLE 13: EMP SUMMARY � WATER QUANTITY MANAGEMENT ............................................. 68


GEO POLLUTION TECHNOLOGIES � GAUTENG (PTY) LTD 8

1 INTRODUCTION

Geo Pollution Technologies, hereafter GPT, has been contracted by Khumani Iron Ore Mine (KIOM)

to conduct a geohydrological assessment that would fulfil the requirements of their draft Water

License dated April 2007.

Khumani Iron Ore Mine is south of the town Kathu, Northern Cape Province, adjacent to Sishen Iron

Ore Mine (SIOM). Mining at the neighbouring SIOM necessitated large scale groundwater abstraction

over more than four decades in order to create suitable and safe mining conditions in the open cast

pit. Apart from use by SIOM, the bulk of the abstracted water is also used to supply the towns of

Kathu and Dingleton with their fresh water needs while the rest is supplied to Sedibeng Water for

further distribution using the Vaal-Gamagara and Kalahari pipelines. Due to this dewatering various

complaints were received from the farming community expressing their concerns regarding the

impact SIOM has on the quality and quantity of their groundwater.

Khumani Iron Ore Mine lies mainly within the dewatered area caused by the dewatering of the

Sishen Open Pit. Based on the current depth to the groundwater table, it is estimated that mining

at KIOM will only intersect the groundwater table 20 years from now, for mining conducted within

the eastern portion of the mine property. Dewatering by KIOM might only be required then, but due

to the allegation made by property owners south and west of the mine, it will be to the benefit of

KIOM to implement a groundwater monitoring system as soon as possible to establish pre-

dewatering groundwater levels. The focus of this study is therefore to establish baseline values for

the groundwater table and groundwater quality within and adjacent to the current and future

dewatered area.

Although the draft water license required the discussion and exchange of the groundwater informa-

tion between KIOM and SIOM, this could not be achieved as a formal contract between the two

mines is still outstanding.

The proposal for the geohydrological work was submitted on 31 May 2009 and the purchase order,

Order Number 9001028 DM, was allocated to GPT on 18 August 2009. The original proposal consisted

of four phases, however after discussions with KIOM, Phase 2, the numerical model of our instruc-

tion, was omitted. Numerical modelling will be done after the completion of this study, when

information on the hydraulic parameters of the aquifer will become available after the installation

of the groundwater monitoring network.

Field work took the form of a comprehensive hydrocensus and groundwater sampling run, mainly

with focus on the areas west, south-west and south of the mine. The fieldwork was carried out

during the months of February and March 2010. Information on farm owners and their complaints

was received from Ms S Cornelissen from the farm Wright and was utilised in the planning of the

hydrocensus to ensure the optimum coverage of the area within our allocated timeframe.

A draft report was submitted at the end of May 2010. This draft report contained a proposed

monitoring network based on data received from DWA and the hydrocensus carried out by GPT.

Verification of this monitoring network took place during June 2010 where the majority of the DWA

data was omitted due to irrelevance/unreliability of the data. This new version includes previous

data and the newly verified monitoring network and management plan. In order to gain a full

understanding of the situation in the area, it is suggested that water level data be shared between

Kumba and Khumani.



2 SCOPE OF WORK

Draft Water License Requirements (April 2007)

The groundwater study must be updated annually before 31 December to determine the source

and extent of groundwater pollution and soil contamination in the area of the Mine Residue

Deposit, Return Water Dam as well as the Plant area.

A groundwater monitoring system approved by the Chief Director must be installed to monitor

possible groundwater pollution in the total mining area.

The licensee shall provide any water user whose water supply is impacted by the removal of

groundwater with potable water. Written contracts must be negotiated with every expected

impacted water user within one (1) month after this license is issued.

A groundwater management plan to address all groundwater pollution must be developed

within a year after issuance in co-operation with the Chief Director.

The groundwater management plan must contain but must not be limited to a number of

actions with milestones agreed upon by the Chief Director to address the progressive reduction

of all potential sources of groundwater pollution.

The impact of dewatering will be most significant along the high yielding zones along the

formations. Additional monitoring boreholes must be drilled to determine the extent of these

zones and the impact of dewatering on them.

Rainfall must be monitored at least at two sites of the mine on a continuous hourly basis.

Draw down intervention limits must be set for the boreholes surrounding the dewatered area.

The groundwater conceptual model must be upgraded as more information becomes available,

with the groundwater model calibrated after every year of data gathering.

Based on the above requirements, it can be concluded that a groundwater monitoring network

should be developed (1) to monitor the impact of dewatering and (2) to monitor the groundwater

quality of potential groundwater pollution sources. As we know that KIOM is mainly within the

dewatered zone, the focus of the study will first be to develop the conceptual model and secondly

to develop the groundwater monitoring network with focus on the determination of the dewatered

area. Thirdly, as a lower priority, boreholes will be drilled in areas of potential groundwater

contamination. (Note: The area is mainly dewatered therefore contamination of groundwater is not

the highest priority). To achieve this, the following scope of work was developed by KIOM:

Collect all available information regarding geology, groundwater and surface waters to obtain

information necessary for impact prediction.

Evaluate the previous geohydrological work conducted at Khumani Mine.

Conduct a detailed hydrocensus of available water resources. Measure the depth to the water

table and take water samples for chemical analysis.

Determine the extent of dewatering impacts in the Khumani area.

Map potential sources of contamination at KIOM.

Evaluate the regional monitoring data to evaluate the possible lateral extent of any possible

groundwater contamination plume and physical aquifer boundaries.

Develop a sound conceptual hydrogeological model of the groundwater flow system.

Utilise the conceptual model to develop an appropriate monitoring system to monitor vertical

and lateral impacts of the mining activities for groundwater impact quantification and

prediction.

Present the findings of the investigation in the form of a concise technical report for submission

to relevant authorities in support of future planning purposes.



In order to develop a cost effective and appropriate but scientifically sound groundwater

monitoring network, the existing monitoring network should be evaluated against the impacts

associated with possible contamination and dewatering of the aquifer systems as indicated by the

conceptual model. The monitoring network will not only address the current situation, but should

also be able to cover the possible future expansion of the dewatering impacted area. The current

situation is that mining at Khumani is within the dewatered area of SIOM. Due to this GPT proposes

the development of the groundwater monitoring system in a step-by-step fashion. Monitoring

boreholes will therefore be drilled in areas with the highest possibility of dewatering followed by

the establishment of the groundwater pollution monitoring system during later stages. Focus is

currently on areas of high priority. All the draft water licence requirements will be fulfilled during

coming phases.

3 METHODOLOGY

In order to satisfy the Scope of Work the following investigations were undertaken:

3.1 DESK STUDY

Due to mining and associated dewatering by SIOM, the Department of Water Affairs initiated a

groundwater level monitoring programme during the early 1970s by establishing a wide network of

monitoring boreholes. Although this network of monitoring boreholes focused on the mine and

property belonging to the owners of the mine, the South African Iron and Steel Corporation (Iscor),

water level observations were also done on surrounding farms as part of regional geohydrological

studies. SIOM currently operate a groundwater monitoring programme using a dedicated borehole

network on their property and some adjoining privately owned land established specifically for this

purpose. Although most of their reports were made available to interested and affected parties,

the data could not be used during this study due to the lack of a contractual agreement between

SIOM and KIOM.

GPT�s initial desk study focused mainly on the vast quantities of historical data which were made

available by the Department of Water Affairs as part of their National Groundwater Database.

Information exists for more than 1 200 boreholes, mainly water level information. Due to the

vastness of the data, a refining process had to be undertaken to evaluate, organise and abstract

only the relevant data. Further information supplied by Khumani consisted of a geohydrological

modelling study (2004) conducted by Clean Stream on behalf of Groundwater Consulting Services to

fulfil the requirements of the EMP report for Bruce-King-Mokaning iron ore mining operation. This

report was also a source of monitoring data as Clean Stream incorporated the SIOM monitoring data

into their groundwater numerical model for KIOM. (Note: None of the original time series data

could be obtained.)

During our contact with the farmers, GPT was informed about the following work initiated by SIOM

to establish the boundaries of the dewatered area:

Geohydrological studies by the consultants Golder Associates.

A study by the consultants Pulles Howard and de Lange (2007) which focused on the Gamagara

River. This study was initiated following heavy rains in the upper catchment of the river and

subsequent reports that the Gamagara River unexpectedly ceased to flow over a section of the

river to the south of the mine. The main focus of this study was to determine to what extent

the disruption of flow in the lower sections of the river has impacted on the resources asso-

ciated with the alluvial aquifer along the river course to the south and west of the mine.

Based on the outcome of these studies SIOM agreed to supply additional water to a selected number

of farms located to the south-west, south, west and north-west of the mine. Negotiations with

individual farm owners led to the implementation of an assistance scheme to identify and supply

additional water resources to individual farms, consisting of a pipeline-based distribution network,

holding tanks, test pumping existing boreholes on farms, and the drilling of new boreholes.



3.2 HYDROCENSUS

The hydrocensus was carried out by K.H. Vermaak and B. van der Westhuizen of Geo Pollution

Technologies during February, March and May 2010. The survey was undertaken with the consent of

the relevant farm owners. The purpose of the groundwater study was explained to the farmers to

ensure cooperation from the landowners who claim to have experienced losses in the yields of their

boreholes.

The following parameters were captured during the hydrocensus:

GPS position

Owner details

Existing equipment

Current use

Reported yield

Reported or measured depth

Static water level

There are 95 hydrocensus boreholes, of which 30 strategically positioned boreholes were sampled

for a chemical analysis. The hydrocensus forms can be seen in the appendix A.

3.3 SAMPLING AND CHEMICAL ANALYSIS

3.3.1 Quality assurance

Geo Pollution Technologies (Pty) Ltd, incorporating our subsidiaries and regional offices, commits

to comply with the Quality Management System and the requirements of ISO 9001:2000.

The methodology followed by GPT for groundwater and surface water monitoring are in accordance

with the American Environmental Protection Agency (EPA). On request of the Client, GPT can

supply Chain of Custody forms, field notes as well as standard operating procedures outlining the

methodology followed for groundwater and surface water monitoring.

The GPT Standard Operating Procedures (SOPs) for groundwater sampling was followed during the

study. One-litre plastic bottles were used for the cation/anion analyses. All the collected ground-

water samples were kept cool prior to their dispatch to the laboratories for analysis. The water

samples were submitted to Clean Stream laboratories in Pretoria.

All monitoring data related to groundwater and surface water were interpreted by GPT using WISH

(Windows Interpretation System for the Hydrogeologist) software and was accordingly assessed in

terms of water quality and temporal trends using WISH version 3.02.180.

The chemical data were compared to the SABS Drinking Water Standards document (SANS 241:2006,

Ed. 6.1) for domestic use.

In interpreting the data and deciding on appropriate action, a Risk Based Approach was used which

requires an understanding of the groundwater in terms of the primary and secondary sources of

contamination, the pathways thereof and the receptor on which the contamination can impact.

3.4 GEOPHYSICAL SURVEY

The geophysical survey was conducted during June 2010.The purpose of the geophysical survey was

to establish positions of additional monitoring wells and also to verify suspected structures.

Electromagnetic (EM) and Magnetic methods were employed during the geophysical survey to map



preferential flow paths. While the magnetic method is used to detect basic intrusions like dolerite

dykes and sills, which is normally associated with groundwater occurrence, the electromagnetic

method detects changes in electrical conductance of the subsurface. As water is normally a

conducting substance in the rock, the method is thus sensitive for the presence of groundwater.

The combination of the two methods lends itself to the identification and preliminary quantifica-

tion of groundwater occurrences.

3.4.1 Magnetometer

Due to the presence of minerals with a high magnetic susceptibility (mainly magnetite) the earth�s

magnetic field induces a magnetic field in some rock bodies. The magnitude of the induced

magnetic field is dependent on the concentration and magnetic susceptibility of these minerals.

Thus, where there is a difference in magnetic susceptibility of rocks, measuring the total magnetic

field can give an indication of subsurface structures, especially dolerite dykes and sills. A proton

magnetometer was used to measure the total magnetic field at intervals of 10 m along the profile

lines.

3.4.2 Electromagnetic method

The electromagnetic survey consists of profiling the subsurface with two connected electrically

conductive loops, one being an electromagnetic transmitter and the other a receiver. By means of

an alternating current in the transmitter loop, secondary currents are induced in the subsurface.

These induced currents are observed with the receiver loop. The instrument is calibrated to give an

apparent conductivity reading. The depth of investigation is a function of the transmitter frequency

and subsurface conductivity, as well as the orientation of the loops. As a rule of thumb, the depth

of investigation is double the coil separation for the vertical dipole and half the coil separation for

the horizontal dipole. However, the skin depth of the subsurface is also an important determinant

of the depth of investigation. As both the above methods rely on measurement of magnetic and

electromagnetic signals, it is evident that metallic structures and power lines will induce artificial

noise on the natural signal. Measurements therefore cannot be taken closer than the loop separa-

tion from such structures.



4 DESCRIPTION OF STUDY AREA

The Khumani Mine is located 10 km south-west of Kathu and approximately 55 km south�west of

Kuruman in the Postmasburg District, Northern Cape Province. The mine is situated to the west of

the R27 arterial road, which also provides the main access to the area. The locality map is shown in

Figure 1.

The topography is characterised by a relatively flat Kalahari plain with a gentle gradient from

around 1 250 mamsl in the south to less than 1 150 mamsl towards the NW and the Gamagara River

valley. Localised prominent hills with elevations of up to 1 350 mamsl occur to the south of the

mine, and Kathu hill lies to the east of the mine with an elevation of 1 284 mamsl.

The Gamagara River flows to the NW following the topographic gradient.

4.1 CLIMATE

Records from the South African Weather Bureaux for the Postmasburg and Kuruman Weather

Stations (years 2000 and 2003) and from the Sishen Weather Station for the years 1961 to 2001 show

that the mean annual rainfall for the area is approximately 386 mm.

The month of July experiences on average, the lowest rainfall with an average monthly rainfall of

0.85 mm, 0.55 mm and 2.00 mm for the Postmasburg, Kuruman and Sishen Weather Stations

respectively.

The month of February experiences on average the highest rainfall with an average monthly rainfall

of 65.65 mm, 57.60 mm and 56.00 mm for the Postmasburg, Kuruman and Sishen Weather Stations

respectively.

4.2 REGIONAL GEOLOGY

The geology in the project area is of vital importance to the development of the conceptual model.

The study area is underlain by the Maremane dome, made up of dolomite and limestone deposits of

the Campbell Rand Supergroup and are regarded as the basement rocks. The general geology can be

seen in Figure 2. The top formation the of the Campbell rand subgroup is the Tsineneng formation.

This formation is of particular interest in the hydrology of the area due to its make-up of dolomites

and breccias. Karst formation is a common occurrence in these sequences.

The chert breccias can reach thicknesses of up to 40 m. The dolomites are unconformably overlain

by the Kuruman Formation of the Asbestos Hills Subgroup. This formation consists of banded iron

formations, jaspilite and some chert.

Diabase intrusions occur as visible dykes in the study area. The dykes have a predominant N-S and

NNE-SSW orientation representing the Ongeluk and Hartley feeder systems. The intrusions have a

significant effect on the geohydrology of the area in the formation of compartments within the

study area. The effects of the dykes can be seen in the water level sections in Figure 20 to Figure

22.

4.3 REGIONAL GEOHYDROLOGY

The hydraulic properties of the area are characterised by shallow dolomitic aquifers with high

transmissivities. The lithologies below the dolomites are characterised by a host interbedded chert,

ironstones, chert breccias, quartzites, conglomerates and shales which would be indicative of

primary and secondary aquifers. Groundwater flow will mainly be in the form of fracture flow.

Porosities vary greatly throughout the lithologies from 1% to 30%.

The dykes in the area that have not been permeated by faulting, form compartments where water

is �dammed up� and greatly disrupt groundwater flow; this phenomenon is known as compart-

mentalisation. The shallow aquifers are of younger age than the dyke structures and are therefore

not intruded by these structures. The implication of this is that the shallow, unconsolidated sandy

aquifers were previously not affected by the dyke structures and water could flow freely across the



top of the dyke structures and the water levels would be more constant throughout the area. As the

water table has now been lowered, the effect of compartmentalisation has now become relevant.

It is likely that the geohydrological regime in the study area is made up of two aquifer systems. The

first, the upper, semi-confined aquifer occurs in the calcrete or on the contact between the

calcrete and underlying Kalahari clay formation, if the latter is present. This aquifer is, however,

often poorly developed in the study area and only sustains livestock and domestic water supply.

Where thick clay layers are developed in this aquifer, a recharge lag time to the underlying

aquifer(s) often occurs. The second, deeper aquifer is associated with fractures, fissures and joints

and other discontinuities within the older hard rock geology of the Transvaal Supergroup and

associated intrusives. The aquifer occurs at depths of between 20 m and 350 m or even deeper in

the study area. Where the upper aquifer is present, mining in the BKM mine boundary area will

completely destroy it but the dewatering effects of the aquifer will not be so widespread due to its

limited depth. The most significant dewatering effect as well as contamination, if present, will be

on the deeper secondary aquifer with higher transmissive properties and more dynamic hydraulic

properties.

Theoretically, water entering the system will migrate vertically downwards until a perched aquifer

is encountered. As the perched aquifer did not feature very prominently during drilling, it is likely

that the recharging water might be retarded, but the majority will continue to migrate downwards

into the saturated zone. From there it will migrate in the direction of the hydraulic gradient until it

eventually enters surface water bodies (i.e. rivers or springs) from where it will flow out as surface

water.

4.3.1 The role and impact of the Gamagara River on the local geohydrology

During the rainy season of 2005/6 the sinkhole problem became apparent to the farmers in the

downstream vicinity of the river. Investigations revealed that the formation of swallet* structures

had occurred.

* A swallet is a type of insurgence with a concentrated water flow, and implies existence of a

subsurface conduit. The surface water enters the subsurface after it has been concentrated

into identifiable streams. The water will usually sink at separate locations that can be seen

and measured as point inputs. Swallet formation is dependent on the presence of impervious

rock formations or thick overburden, which provides a surface on which meteoric water can

collect as surface streams. For inventory purposes, a swallet may also refer to a concen-

trated water loss in a streambed even though there is no marked depression. A swallet refers

to the site of the water loss, not the stream that leads to it. In many cases, the growth and

evolution of a subsurface conduit system results in the abandonment of some swallets in

favour of new upstream swallets called progressive swallets. The adjective abandoned is

applied to describe the older inactive insurgence. Swallets that are only utilised when

upstream insurgences cannot handle peak water flows are termed overflow swallets.

Swallets frequently occur in clusters or complexes associated with the course of pre-existing

subsurface conduits. This is because the underlying conduits serve as a drain for surface

water. Swallets can also cluster if one of the insurgences cannot accommodate peak flows,

resulting in the use of overflow swallets. In mantled karst units, swallets tend to cluster

where the soluble rock is exposed, as this is where surface water flow is more likely to sink.

� Prof. G.J. van Tonder, Institute for Groundwater Studies, University of the Free State

The Gamagara valley traverses the study area and is an important alluvial aquifer, which is filled

with up to 10 m of fine quartzitic sand and runs across various formations and rock types. In places

along the river, swallets have formed along fault structures which result in the capturing of vast

amounts of water during flood events. One particular swallet of concern is the one located near the

old golf course. The remainder of the downstream shallower alluvial aquifer is therefore deprived of

any recharge from flood events.



Figure 1: Locality map



Figure 2: Geology at the project area with the boreholes sampled during the hydrocensus.



5 RESULTS OF INVESTIGATION

5.1 HYDROCENSUS

The hydrocensus was mostly conducted in a 12 km radius of the mine boundary. The potential radius

of influence on the groundwater regime around an iron ore mine in this area has been shown from

nearby examples to be potentially significant. The radius of influence depends strongly on

geological structures such as faults (preferred groundwater flow paths), and dykes (horizontal flow

barriers), groundwater gradients and nearby mining operations where dewatering already occurs

and the presence of other groundwater production boreholes in the area.

The western side yielded more boreholes along the Gamagara River than on the eastern side

because of the greater abundance of farm owned property on the western side. The survey was also

extended beyond the 12 km radius to the SW where the contact zones of the numerous SW-NE

striking dykes could form preferential groundwater flow paths and hence render this area poten-

tially more prone to dewatering influences. Water levels of the boreholes located vary from

4.84 mbgl (metres below ground level) to 110.8 mbgl. The deep water levels are characteristic of

the dewatered areas.

There are 95 hydrocensus boreholes. The main characteristics of the hydrocensus data are sum-

marised in Table 2. A list of the boreholes located on the mine property is given in Table 3 and can

be seen in Figure 4. Any boreholes where the static water level could not be measured were

excluded from the hydrocensus. This had no influence on the data, as there were enough boreholes

available with easy access to water levels. The positions of all the boreholes relative to the area are

shown in Figure 3. Details of the hydrocensus, containing details like the owner and use, are

attached as Appendix A in a separate PDF file.

The majority of the boreholes visited were equipped with wind pumps for the supply of domestic

water as well as for livestock watering. No irrigation was noted in the area during the hydrocensus.

The two boreholes located on Parsons were provisionally equipped with pumps and meters but were

not in use at the time of the investigation. Photographs of these boreholes can be seen in

Appendix A.

The Draft Water Licence authorises the abstraction of a maximum quantity of 20 652 m3 per annum

(twenty thousand six hundred and fifty two cubic metres per annum) based on an average quantity

of 57 m3/d (fifty seven cubic metres per day) from groundwater resources on Parson 564 Portion 2

and remaining extent of the farm for construction only.

The abstraction points can be seen in Table 1 below:

Table 1: Parson abstraction points and corresponding allowed abstraction volumes

ABSTRACTION

POINT FARM CO-ORDINATES

AVERAGE VOLUME

ABSTRACTED/ANNUM

PBE 01 Parson 564 Ptn 2 RE 27

° 51� 03.2� S

22° 59� 02.6� E

14 832 m³

PBW 02 Parson 564 RE 27

° 51� 29.6� S

22° 57� 08.0� E 5 820 m³



Figure 3: Hydrocensus borehole positions with depth to water level (mbgl)



Table 2: Summary of the hydrocensus data

BH NO OWNER BH NO SAL (MBGL) OWNER FARM USE

1 ALK 3/27 16.50 Assmang King Monitoring


3 PBW 01 8.48 Assmang Parsons Monitoring

4 PBW 04 13.88 Assmang Parsons Monitoring

5 GP 01 6.74 Stephanie Cornelissen Frits Domestic

6 WRIGHT 6 16.08 Stephanie Cornelissen Wright Livestock watering

7 Pbh 02 10.03 George Poolman Gamagara Monitoring

8 Pbh 07 no ac George Poolman Gamagara Domestic

9 Pbh 05 8.05 George Poolman Gamagara Domestic

10 Cbh 02 8.51 Pieter Coetzee Dingleton Domestic, Livestock watering

11 Cbh 01 8.08 Pieter Coetzee Dingleton Domestic, Livestock watering

12 Mbh 01 - Mynhardt Gamaliets Domestic

13 Mbh 02 - Mynhardt Gamaliets -

14 A 01 Block Jannie Coetsee Reitz plotte Domestic, Livestock watering

15 Huis 46.36 Dihan van Rensburg Demaneng Domestic

16 3A 15.90 Dihan van Rensburg Demaneng Monitoring

17 c 1C no ac Dihan van Rensburg Demaneng Livestock watering




17 1A 49.16 Dihan van Rensburg Demaneng Monitoring

18 Leg sonpomp 43.50 Dihan van Rensburg Legogo Livestock watering

19 Leg Wes 26.23 Dihan van Rensburg Legogo Monitoring

20 Son pomp 11.00 Dihan van Rensburg Mashwening Livestock watering

21 Suid 46.46 Dihan van Rensburg Mashwening Monitoring

22 no 7 20.81 Nick de Ath Crossley Livestock watering

23 no 4 14.44 Nick de Ath Crossley Domestic, Livestock watering

24 JBH1 no ac Nick Steyn Jenkins Domestic, Livestock watering

25 JBH2 no ac Nick Steyn Jenkins Domestic, Livestock watering

26 JBH3 12.22 Nick Steyn Jenkins Domestic, Livestock watering

27 JBH4 15.68 Nick Steyn Jenkins Livestock watering

28 JBH5 4.84 Nick Steyn - Domestic, Livestock watering

29 JBH6 5.47 Nick Steyn - Livestock watering

30 JBH7 no ac Nick Steyn Kadgame Livestock watering

31 JBH8 6.47 Nick Steyn Kadgame Livestock watering

32 JBH9 0.00 Nick Steyn Kadgame Livestock watering

33 ABH05 18.68 J.M. Fourie Diban Domestic




34 ABH06 no ac H.J. Croucamp Murray -

35 ABH07 16.63 H.J. Croucamp Murray Domestic, Livestock watering

36 ABH08 20.08 P.J. Steenkamp Smythe Domestic

37 - no ac P.J. Steenkamp Smythe Domestic

38 - 19.88 S. Du Plessis Smythe Domestic, Livestock watering

39 - 21.08 J.P. Steenkamp Smythe Monitoring

40 - 20.88 J.P. Steenkamp Smythe Monitoring


42 AGK 4/63 no ac Assmang King Monitoring

43 AHK 3/61 no ac Assmang King Monitoring

44 Lanham 1 10.55 Andre van Zyl Lanham -



47 Lanham 5 6.97 Andre van Zyl Lanham Monitoring

48 Lanham 6 16.07 Andre van Zyl Lanham Monitoring

49 Edenvale 1 12.08 J.P. Lock Edenvale Monitoring






52 Wright 1 12.03 Stephanie Cornellisen Wright Monitoring



55 AMK 1/47 31.00 Assmang Khumani - Monitoring

56 AGK 1/89 20.90 Assmang Khumani - Monitoring

57 AAK 2/45 17.80 Assmang Khumani - Monitoring

58 WK 4/70 110.80 Assmang Khumani - Monitoring

59 VK 3/67 A 17.70 Assmang Khumani - Monitoring

60 KM 3/24 64.00 Assmang Khumani - Monitoring

61 AKK4/26 17.50 Assmang Khumani - Monitoring

62 ABK 2/46 63.20 Assmang Khumani - Monitoring

63 ALK 2/49 25.90 Assmang Khumani - Monitoring

64 VLK 02 - Jaco Kahn Vlakwater Domestic, Livestock watering

65 VLAK02 20.76 Jaco Kahn Vlakwater Domestic, Livestock watering

66 VLK 01 11.8 Jaco Kahn Vlakwater Domestic, Livestock watering

67 VLK03 - Jaco Kahn Vlakwater Domestic, Livestock watering




68 GAM01 - Mr. Maynard Gamaliets Domestic

69 GAM 02 - Mr. Maynard Gamaliets -

70 18.71 Mr. Maynard Gamaliets Livestock watering

71 GAM04 18.79 Mr. Maynard Gamaliets Livestock watering

72 GAM05 21.88 Mr. Maynard Gamaliets Domestic, Livestock watering

73 FAM06 21.57 Mr. Maynard Gamaliets Livestock watering

74 Lang04 25.15 Koos Maritz Langlaagte -

75 Lang05 - Koos Maritz Langlaagte -

76 Lat1 - Koos Maritz Langlaagte -

77 Lat9 - Koos Maritz Langlaagte Livestock watering

78 Lang01 - Koos Maritz Langlaagte Livestock watering

79 Lat7 - Koos Maritz Langlaagte Livestock watering

80 GAP06 26.46 Gert Maritz Gappepin Livestock watering








85 GAP01 - Gert Maritz Gappepin -

86 ROC8 23.62 Jan Olivier Gamaliets Livestock watering



89 ROC1 - Jan Olivier Gamaliets -


91 ROC6 - Jan Olivier Gamaliets -

92 ROC5A 17.02 Jan Olivier Gamaliets Domestic, Livestock watering

93 ROC5 17.10 Jan Olivier Gamaliets Domestic, Livestock watering

94 ROS1 18.61 Jan Olivier Roscoe farm Livestock watering



Table 3: Boreholes Located on Khumani Mine property

X Y

Mashwenin 23.04852 -27.88725 Assmang

Mashwenin 23.05661 -27.89595 Assmang

Mokaning 1 23.02961 -27.88651 Assmang

Mokaning 2 23.03508 -27.89274 Assmang

King 3 22.99544 -27.84960 Assmang

King 2 23.00122 -27.85562 Assmang

King 1 22.98810 -27.87321 Assmang

BKM 1 23.01456 -27.77299 Assmang

BKM 3D 22.99097 -27.88483 Assmang

PBW 01 22.96931 -27.84925 Assmang

Parsons1 22.98481 -27.85842 Assmang



AGK2/87 22.98680 -27.88750 Assmang

AIK1/45 23.00110 -27.88580 Assmang

VK2/81 22.98370 -27.86950 Assmang

VK1/49 22.98270 -27.86770 Assmang

WK2/35 22.99590 -27.86720 Assmang

QK4/55 22.99590 -27.86360 Assmang

QK4/70 22.99850 -27.86410 Assmang

QK2/9 22.99800 -27.85700 Assmang

ZR3/24 23.02080 -27.80800 Assmang

ABK2/42 22.99440 -27.87670 Assmang

ZR3/2 23.01980 -27.80720 Assmang

AMK1/47 22.99230 -27.89430 Assmang

AGK1/89 22.98320 -27.88710 Assmang

AAK2/45 22.98620 -27.87630 Assmang

WK4/70 22.99900 -27.87280 Assmang

VK3/67A 22.98220 -27.87270 Assmang

KM3/24 23.00050 -27.88930 Assmang

ALK3/22 22.97960 -27.89790 Assmang

AKK4/26 22.97610 -27.89840 Assmang

ABK2/46 22.99640 -27.87670 Assmang

AAK3/27 22.98170 -27.88030 Assmang

ALK2/49 22.98780 -27.89480 Assmang

PBE01 22.98360 -27.85130 Assmang

PBW01 22.96170 -27.84300 Assmang

PBW02 22.95180 -27.85870 Assmang

PBW03 22.96690 -27.85230 Assmang

PBW04 22.95850 -27.86920 Assmang

BKM1 23.01460 -27.77310 Assmang

BKM2 23.01850 -27.84700 Assmang

BKM3D 22.97930 -27.87770 Assmang

BKM4 23.02650 -27.86740 Assmang

LocationBorehole Number Owner



Figure 4: Locations of boreholes on Khumani Mine property



5.2 WATER QUALITY

Water was sampled from 30 boreholes (Figure 5) around the site during the investigation, and

submitted for major cation and anion analyses to determine water quality in the area. These are

the boreholes sampled during March 2010. The results from these analyses are contained in Table 5

to Table 5 and are compared to the SANS Drinking Water Standards (SANS 241:2006, Ed. 6.1). The

SANS classification was used to critically evaluate the current data and verify whether all sources of

contamination have been identified and characterised. Colours of individual cells refer to the

drinking water classification of the specific groundwater sample. The results from these analyses

were plotted as Stiff diagrams (Figure 6 and Figure 7) and a Piper diagram (Figure 9). Details of the

chemical analyses are attached in a separate PDF file as Appendix B.

The Stiff and Piper diagrams serve as both indicator of the level of mineralisation and as a

�fingerprint� of the type of mineralisation. The Stiff diagram is a polygon created from three

horizontal axes extended on both sides of a vertical axis. The cations are plotted on the left side of

the axis while anions are plotted on the right side, both in meq/L. A greater distance from the

vertical axis represents a larger ionic concentration. The cation and anion concentrations are

connected to form an asymmetric polygon, where the size is a relative indication of the concen-

tration of major ions. Different sources of pollution can be deduced on the grounds of the shape of

each diagram. Piper diagrams provide a convenient method to classify and compare water types

based on the ionic composition of different water samples (Figure 8). Cation and anion concen-

trations for each groundwater sample are converted to total meq/L and plotted as percentages of

their respective totals in two triangles. The cation and anion relative percentages in each triangle

are then projected into a quadrilateral polygon that describes the hydrochemical facies. WISH

Software was used in the interpretation of the chemical results.

The impact of the contribution of the licensee on the quality of the groundwater measured at the

monitoring points must comply with the preliminary water quality reserve as indicated in Table 4

below.

Table 4: Water quality requirements

pH 8.3

Electrical Conductivity (mS/ m) 115.6

Total Dissolved Solids (mg/l) 827

Calcium as Ca (mg/l) 93.8

Magnesium as Mg (mg/l) 70.4

Sodium as Na (mg/l) 60.0

Potassium as K (mg/l) 4.9

Chloride as Cl (mg/l) 140.5

Total Alkalinity as CaCO3 (mg/l) 364.8

Sulphate as SO4 (mg/l) 80.6

Nitrate as NO3 (mg/l) 14.8

Fluoride as F (mg/l) 0.5



Table 5: Results of major cation and anion analyses

Sample No. BH 1 BH2 BH3 BH4 BH5 BH6 BH8 BH9 BH11 BH14 Class I Class IICa 86.33 44.53 68.75 33.51 48.48 38.80 47.18 48.62 85.05 74.34 150 300Mg 59.53 7.51 44.44 32.31 78.69 46.57 103.26 74.77 97.67 45.61 70 100Na 14.45 94.53 42.11 39.19 59.20 27.97 86.49 96.15 71.84 18.22 200 400K 1.69 2.55 2.40 1.70 2.66 3.30 2.86 3.04 2.79 2.29 50 100

Mn 0.00 0.06 0.00 0.00 0.00 0.00 0.00 0.20 0.00 0.00 0.1 1Fe 0.02 5.16 0.07 0.08 0.07 0.07 0.07 0.07 0.02 0.02 0.2 2F 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1 1.5N 8.19 0.00 8.18 0.00 18.18 8.84 18.22 9.77 7.35 1.43 10 20Al 0.00 0.03 0.02 0.03 0.02 0.02 0.02 0.02 0.00 0.00 0.3 0.5Cl 40.50 34.40 42.40 43.40 79.30 19.60 90.10 48.50 90.10 44.50 200 600

SO4 45.20 0.00 39.41 0.24 70.62 18.01 88.58 53.68 306.81 27.32 400 600TDS by sum 460.00 378.00 417.00 311.00 534.00 348.00 695.00 590.00 890.00 390.00 1000 2400

M-Alk (CaCO3) 340.70 324.40 282.80 268.10 295.40 308.60 430.00 425.90 381.00 293.10 - -pH 7.63 7.36 7.93 7.08 8.29 8.24 8.26 8.25 7.82 7.87 5.0 - 9.5 4.0 - 10.0EC 75.40 66.00 68.20 8.52 68.40 67.10 67.20 67.30 101.00 67.00 150 370

0 = below detection limit of analytical technique

Exceeding maximum allowable standard for domestic useClass IIClass INotes:

na - not analysedAll concentrations are presented in mg/l, EC is presented in mS/m




Sample No. BH15 BH16 BH17 BH18 BH19 BH20 BH21 BH22 BH23 BH26 BH27 Class I Class IICa 53.19 6.13 60.93 56.61 63.70 72.53 70.88 57.45 38.52 60.42 69.46 150 300Mg 61.18 40.56 70.33 13.92 28.59 45.48 43.89 28.01 20.29 81.91 49.15 70 100Na 25.18 17.04 29.53 5.84 0.00 15.62 8.02 15.25 6.92 11.98 8.09 200 400K 2.88 2.39 3.12 2.09 1.19 2.39 1.23 0.34 0.36 1.33 2.19 50 100

Mn 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.1 1Fe 0.02 0.02 0.01 0.01 0.01 0.01 0.01 0.07 0.07 0.07 0.09 0.2 2F 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1 1.5N 6.25 0.00 8.34 2.85 2.13 3.56 9.91 12.28 5.63 15.74 8.28 10 20Al 0.00 0.00 0.01 0.01 0.00 0.00 0.00 0.02 0.03 0.02 0.02 0.3 0.5Cl 46.30 40.20 52.60 38.10 0.00 24.30 26.10 14.40 4.80 76.10 27.90 200 600

SO4 44.37 12.34 39.48 17.12 0.68 61.26 6.77 17.35 23.36 36.36 29.87 400 600TDS by sum 405.00 207.00 456.00 204.00 252.00 426.00 361.00 258.00 177.00 497.00 354.00 1000 2400

M-Alk (CaCO3) 275.90 148.00 319.30 113.00 259.60 334.30 323.00 188.90 129.30 355.10 265.20 - -pH 7.94 8.51 7.74 7.87 7.71 7.69 7.63 7.48 7.83 7.70 7.93 5.0 - 9.5 4.0 - 10.0EC 69.70 43.20 74.00 42.80 51.20 74.60 71.70 50.80 38.30 89.40 62.80 150 370

0 = below detection limit of analytical technique


na - not analysedAll concentrations are presented in mg/l, EC is presented in mS/m




Sample No. BH 28 BH29 BH30 BH32 BH33 BH34 BH35 BH36 BH39 BH40 Class I Class IICa 78.59 20.38 43.46 57.43 72.61 65.13 61.89 43.70 33.77 45.28 150 300Mg 161.81 124.16 89.35 102.09 82.40 42.87 42.07 44.58 11.45 55.53 70 100Na 46.19 14.44 10.73 15.22 75.74 10.59 11.52 21.96 31.44 22.22 200 400K 2.86 0.23 0.41 0.24 3.34 2.26 2.22 2.40 2.25 2.76 50 100

Mn 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.04 0.00 0.1 1Fe 0.07 0.08 0.08 0.08 0.07 0.07 0.07 0.07 0.07 0.07 0.2 2F 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1 1.5N 7.15 4.64 4.18 2.90 23.20 11.84 11.88 11.05 1.33 5.94 10 20Al 0.02 0.03 0.03 0.02 0.02 0.02 0.02 0.03 0.03 0.02 0.3 0.5Cl 91.70 42.30 26.30 61.30 189.20 54.40 44.70 29.80 32.40 32.10 200 600

SO4 111.08 48.97 47.97 64.93 72.36 21.02 16.81 24.49 30.36 22.00 400 600TDS by sum 866.00 555.00 492.00 597.00 703.00 342.00 324.00 337.00 210.00 386.00 1000 2400

M-Alk (CaCO3) 611.20 500.30 449.90 488.50 306.70 222.60 221.10 265.00 112.20 332.90 - -pH 7.90 7.70 8.30 8.27 8.50 8.31 8.24 8.31 7.55 7.54 5.0 - 9.5 4.0 - 10.0EC 108.30 92.70 67.20 67.40 194.40 66.40 65.60 66.20 141.10 210.50 150 370

na - not analysedAll concentrations are presented in mg/l, EC is presented in mS/m0 = below detection limit of analytical technique




Figure 5: Borehole positions where samples were collected



Figure 6: Stiff diagrams for major cations and anions



Figure 7: Stiff diagrams for major cations and anions



Figure 8: Diagram used in the interpretation of Piper diagrams

Figure 9: Piper diagram for major cations and anions.

The Piper diagram shows that the waters are calcium/magnesium bicarbonate waters, with the

exception of one outlier (BH2) which shows the characteristics of sodium bicarbonate type waters.

Figure 10 below shows the concentrations of magnesium in the study area.



Figure 10: Concentrations of magnesium in the study area



Figure 11: Box and whisker plots of chloride, calcium, and aluminium

The chloride, calcium and aluminium values of the waters are within the SANS drinking water

quality guidelines although the draft water licence requires that the chloride values do not exceed

140.5. The chloride levels in BH33 exceed those required in the draft licence. The calcium values

fall within the draft water licence requirements.

Figure 12: Box and whisker plots of sodium and sulphate

The sodium and sulphate values are within acceptable SANS standards but several sulphate values

do not comply with draft water licence standards. These boreholes are BH11, BH28 and BH8.

Similarly some of the sodium values do not meet the draft water licence requirements, namely BH2

BH8 and BH9.



Figure 13: Box and whisker plots of iron

The iron values are within acceptable standards with the exception of borehole BH2 which is not

within accepted standards. This anomaly cannot be linked to mining activities because surrounding

boreholes do not show any elevated iron values. The location of this borehole can be seen in Figure

5. A possible source for the high iron value could be the borehole casing.

Figure 14: Box and whisker plots of magnesium

High magnesium values can be seen in boreholes BH29, BH28, BH32 and BH8. Mining activity does

take place in the area where these high values occur. The values in BH26, BH11, BH29, BH28, BH30,

BH32, BH33 and BH8 do not fall within the water licence requirements acceptable levels.



Figure 15: Box and whisker plots of electrical conductivity and total dissolved solids.

The electrical conductivity values fall within the SANS acceptable limits. The total dissolved solids

values of BH11 and BH28 do not fall within the draft water licence requirements. Numerous

electrical conductivity values do not fall within the draft water licence requirements.

Figure 16: Box and whisker plots of nitrates

The Nitrate values are within SANS accepted standards and the draft water licence requirements

with the exception of one borehole, BH33 which is higher than the SANS standards. The high value

can be attributed to agricultural activities.



Figure 17: Box and whisker plots of pH values of the samples taken

The pH values all fall within accepted standards and pose no threat.

The general water quality falls within the accepted SANS water quality guidelines, although some of

the water qualities do not fall within the requirements set out in the draft water licence.

5.3 DEPARTMENT OF WATER AFFAIRS (DWA) DATABASE

It was necessary to acquire time series data from DWA in order to determine the historic dewatering

of the area. DWA supplied the data in digital format. The data of 1 723 boreholes were supplied, of

which only 480 contained relevant data which were used in the report (Figure 23). The data contain

borehole numbers, co-ordinates and water levels for a set amount of time. The time series data end

during the late eighties and early nineties.

5.4 WATER LEVELS

The use of water levels in the prediction of groundwater flow directions is a commonly used

practice. The groundwater levels determine the local direction of groundwater flow directions,

while the changes in the levels could identify whether mining is impacting on the groundwater

levels.

Water levels were measured at various locations around the study area in the form of a complete

hydrocensus. Groundwater normally follows the topography to a large degree. The groundwater

level is generally deeper in higher lying areas and shallower near drainage areas like local streams

etc. Usually a good relationship should hold between topography and static groundwater level. This

relationship can be used to distinguish between boreholes with water levels at rest, and boreholes

with anomalous groundwater levels due to disturbances such as pumping or local geohydrological

heterogeneities. The relationship using the static water levels of the boreholes from the

hydrocensus is shown in Figure 18 below. The water levels are given as metres above mean sea level

(mamsl) and metres below ground level (mbgl).The correlation can be described as poor to average.

This general relationship is useful to make a quick calculation of expected groundwater levels at

selected elevations, or to calculate the depth to the groundwater level (unsaturated zone):

Groundwater level = (Elevation x 0.8802) + 162.76

Depth to the groundwater level = Elevation x (1 � 0.8455)

= Elevation x 0.1545



However, due to the heterogeneity of the subsurface, these relationships should not be expected to

hold everywhere under all circumstances, and deviations could therefore be expected.

Water Level Correlation

y = 0.8802x + 162.76

R2 = 0.8455

1100

1150

1200

1250

1300

1350

1050.0 1100.0 1150.0 1200.0 1250.0 1300.0 1350.0

Elevation (mamsl)

Wat

er L

evel

(m

amsl

)

Series1Linear (Series1)

Figure 18: Correlation graph

From the water levels attained, Kriging interpolation can be used in the construction of a water

level contour map. Due to a lack in data in certain areas and an insufficiently accurate water level

correlation, the construction of a water level contour map was not a reliable method.

5.4.1 Water level sections

Three water level sections (Figure 20, Figure 21 and Figure 22) were constructed and their locations

can be seen in Figure 19 below.

A clear correlation can be seen between the change in geology and the change in water level on the

water level sections. This is a clear indication of the effect of structures within the geology

influencing the water levels. For a more clear indication of the effect of the structures on the water

levels see Figure 35.

The effect of dyke structures has been a subject of controversy in the various studies conducted in

the area. The general rule is that dykes form an impermeable no-flow boundary. The scenario in the

study area is different, in that two major factors contribute to the dykes being permeable or semi-

permeable:

The first is that the dykes are cross-cut by faults which cause preferential flow paths in the

form of fractured zones through the dykes.

A second contributing factor is the pressure formed when a compartment is dewatered and the

adjacent compartment is not. This causes a hydraulic head across the dyke, which in turn would

encourage possible groundwater flow across the dyke.

5.4.2 Historical water levels

The use of historical water levels is of great importance in this project. Water levels supplied by the

Department of Water Affairs (DWA) date as far back as 1961. These water levels are plotted against

time, so as to see the variations in the water levels. The locations of the boreholes monitored by

DWA can be seen in Figure 23 below. The integrity of this data is questionable.



Dramatic and distinct water level changes can be noted as far back as the mid 1970s. These drops in

water levels can clearly be seen in boreholes located in the close vicinity of the SIOM. Although no

recent DWA data are available it is clear that the mine on the north-eastern boundary had a

significant effect on the regional water levels. The extent of the dewatering can be seen in Figure

24 based on the DWA data.

5.4.3 Area impacted by dewatering base on DWA data

Using historical DWA data the area of influence can be determined. DWA monitoring of the region

ceased in the early nineties. The monitoring data therefore end during this period.

It is important to note that this data is based on unverified DWA data and in the absence of Kumba

data. The proposed dewatered area is based on this data. It must be mentioned that Khumani is not

responsible for the dewatering that has taken place as they has not yet begun abstracting any water

for mining activities.

It must be emphasised that the data acquired from DWA do not give an ideal up-to-date dewatered

area due to the data being obsolete, although a general trend for the dewatering in the area is

gained. In places where no historical data are available; these areas are demarcated by a dotted

line.

From the demarcated dewatered area it has become clear that due to a lack of data in the southern

and north-eastern areas of the Khumani Mine boundary, the extent of the dewatering cannot be

delineated exactly. It is therefore of utmost importance to have an appropriate monitoring network

with boreholes strategically placed, so as to monitor the quantity and quality of the water in the

affected area. A well designed monitoring network will also give a better delineation of the

dewatered area.

The demarcated area based on the DWA data is shown in Figure 25. Due to the sensitivity of the

area, a further investigation was conducted in order to verify the DWA database. The time series

data can be seen in Appendix E.



Figure 19: Location of water level sections based on hydrocensus boreholes located during February and March.



Waterlevel section 1

1160.01180.01200.0

1220.01240.01260.01280.0

1300.01320.01340.0

0 5000 10000 15000 20000 25000 30000 35000

Distance (m)

Ele

vati

on

(m

amsl

)

Waterlevel

Elevation

Figure 20: Water level section across the study area

Water Level Section 2

1140.0

1160.0

1180.0

1200.0

1220.0

1240.0

1260.0

0 5000 10000 15000 20000 25000

Distance (m)

Ele

vati

on

(m

amsl

)

WaterlevelElevation

Figure 21: Water level section across the study area

Water Level Section 3

1180.0

1200.0

1220.0

1240.0

1260.0

1280.0

1300.0

0 5000 10000 15000 20000 25000

Distance (m)

Ele

vati

on

(m

amsl

)

Waterlevel

Elevation

Figure 22: Water level section across the study area.



Figure 23: DWA borehole locations � historical data



Figure 24: Dewatering impact area based on DWA data



Figure 25: Map showing the DWA boreholes on the demarcated boundary, refer to Appendix C and E for complete details



6 CONCEPTUAL MODEL

A conceptual model is a representation of the perceived reality of a given scenario based on known

information/data of that area/scenario. The more information that is known about an area will

result in a better conceptual model. The conceptual model represents the best idea if how the

aquifer works under a specific set of conditions. Developing a good conceptual model for an area

requires that we have detailed information including geology, water quality, recharge, abstraction

in the area, groundwater flow direction, sources, sinks, rivers in the area, hydraulic parameters and

accurate water levels. It must be noted that once a conceptual model has been developed, it may

become obsolete over time as more data are gathered and a better understanding of the area is

gained.

The data has its limitations in terms of lacking data on the northern, south-eastern and eastern

areas. The conceptual model for the project area will be discussed in terms of the following:

6.1 CONCEPTUAL MODEL BOUNDARIES

Due to the fact that the dewatering is taking place in shallow as well as deep aquifers the lateral

extent of the dewatering has the potential of having an effect over a considerable area. The dykes

in the area could be partially permeable because of high hydraulic gradients and faulting creating

preferential flow paths across the dykes. A likely boundary in the south is located on a structure on

the farm Macarthy where a spring has formed on the surface. The location of this spring is

S 27.93960 E 23.04245. The spring is reported to be perennial and has reportedly not ceased flowing

for the last 15 years. The spring can be seen in the photo below.

Figure 26: Spring located on Macarthy farm

The total depth from ground surface to the aquifer ranges from approximately 5 metres to

100 metres. The furthest points away from the point of dewatering will experience the least effect

and therefore least water level drop.



6.2 GROUNDWATER CONSIDERATION

6.2.1 Hydraulic properties

The hydraulic properties of the area are characterised by shallow dolomitic aquifers with high

transmissivities. The lithologies below the dolomites are characterised by a host interbedded

cherts, ironstones, chert breccias, quartzites, conglomerates and shales which would be indicative

of primary and secondary aquifers. Typical transmissivities will be in the order of 10 m2/d.

Water flow will be in the form of fracture flow in the fractured aquifers and porous flow in primary

aquifer systems.

6.2.2 Discharge/Pumping from the aquifer

Water is constantly pumped in the area, hence the dewatering. Exact quantities and histories of

pumping are not known, although it is possible to conclude that dewatering commenced during the

1970s.

6.2.3 Flow directions

Due to the extraction taking place in the area it is assumed that the natural conditions no longer

exist. Therefore the general flow direction will be towards the major points of abstraction in the

area. Flow directions will as a rule of thumb follow the topography of the area.



7 MONITORING NETWORK

A detailed understanding of the conceptual hydrogeological model (CHM) of the area will be

required before embarking on any actions.

7.1 GROUNDWATER MONITORING NETWORKS

It is important to note that the monitoring network should be dynamic. (Draft licence requirements

in scope of work.) This means that the network should be extended over time to accommodate the

migration of contaminants through the aquifer as well as the expansion of infrastructure and/or

addition of possible pollution sources. An audit on the monitoring network should be conducted

annually. A groundwater level observation network within the area of dewatering and area of

possible impact of dewatering must be established at commencement of water use.

The monitoring network must comply with the requirements set out as per the issued water licence.

The requirements of the water licence will be incorporated within the monitoring network as

described in this report. Although the draft licence is specific in terms of where and what to

monitor the network has to adhere to source, plume, receptor/impact and background monitoring.

7.1.1 Source, plume, impact and background monitoring

No water quality monitoring boreholes have been recommended due to current absence of data

regarding the locations of the proposed infrastructure. When this data is made available the

necessary borehole location recommendations will be made.

Source monitoring � monitoring boreholes are located close to or in the source of con-

tamination to evaluate the impact thereof on the groundwater chemistry.

Plume monitoring � monitoring boreholes are placed in the primary groundwater plume�s

migration path to evaluate the migration rates and chemical changes along the pathway.

Impact monitoring � monitoring of possible impacts of contaminated groundwater on sensitive

ecosystems or other receptors. These monitoring points are also installed as early warning

systems for contamination breakthrough at areas of concern.

Background monitoring � background groundwater quality is essential to evaluate the impact of

a specific action/pollution source on the groundwater chemistry.

7.2 SYSTEM RESPONSE MONITORING NETWORKS

Groundwater levels

The response of water levels to rainfall events are monitored for accurate calculation of recharge to

the groundwater regime. Static water levels are also used to determine the flow direction and

hydraulic gradient within an aquifer. All of the water levels of the above-mentioned boreholes need

to be recorded during each monitoring event. All the abstraction boreholes are to be fitted with

meters and volumes are to be recorded on a daily basis. The monitoring network to be used can be

seen in Figure 27. This proposed monitoring network is based on the work done during February and

March 2010 and the historical data gained from DWA.



Figure 27: Proposed monitoring network based on DWA data and hydrocensus



8 VERIFICATION OF CONCEPTUAL MODEL

In the process of the verification of the monitoring network, the data on which the original

monitoring network was based had to be verified.

An investigation was carried out whereby as many boreholes as possible were visited to ascertain

their status, and to verify whether the boreholes could be used for monitoring. It was found that a

large number of the boreholes no longer existed or were not in use. The few boreholes that were

still in use were not suitable to be used in the monitoring network.

It became apparent that the southern areas of the mine had to be monitored for future impacts on

the neighbouring farmers. It was therefore necessary to use alternative boreholes and site new

boreholes using geophysics.

8.1 GEOPHYSICAL SURVEY

A geophysical survey was conducted by Mr K. Vermaak in the southern areas around the mine. The

main aim of the geophysical survey was to locate possible drilling positions where future Loecell

monitoring boreholes could be located. These boreholes will measure and monitor the future

dewatering impacts in the southern reaches of the mining area. The boreholes would monitor the

effect of the structures on the groundwater levels. The traverse locations were determined using

aerial photographs and satellite imagery and can be seen in Figure 28 to Figure 33. A summary of

the traverses and the findings of each traverse can be seen in Table 8 below. The geophysical

profiles are appended under Appendix D.

Table 8: Summary of traverse information

Traverse no. Traverse

direction Length (m) Observations

Roscoe Farm -

Traverse 1 N-S 900

A distinct magnetic anomaly was noted between the

400 m and 700 m mark, interpreted as a possible dyke.

The electromagnetic method showed a corresponding

anomaly at 520 m. It is recommended that a borehole

be drilled adjacent to this structure. See Figure 31.

Roscoe farm

Traverse 2 & 3 290° 130

It was decided to abandon this traverse due to thick

bush. The traverses were relocated and the

observations can be seen in Traverse 4. See Figure 32.

Roscoe farm

Traverse 4 290° 430

Due to the thick bush in the area it was decided to use

only the magnetometer. The magnetic method showed

a clear anomaly between 200 m and 400 m. It is

recommended that a borehole be drilled adjacent to

this structure. See Figure 33.

Macarthy


A clear anomaly can be noted between 30 m and

50 m. It is possible that this anomaly could be a sub-

vertical structure. The electromagnetic method in

Macarthy Traverse 2 is complimentary to this. See

Figure 29.

Macarthy


The electromagnetic method showed an anomaly

between 60 m and 90 m, indicative of the possibility

of a sub-vertical structure. See Figure 29.

Macarthy

Traverse 3 S-N 140

The magnetic and the electromagnetic methods were

used over the same traverse. A possible structure is

located between 60 m and 100 m where the magneto-

meter and the EM show anomalies. See Figure 30.

Bruce

Traverse 1 S-N 990

No significant anomalies were noted along this

traverse, therefore no drilling is recommended.



Figure 28: Location of geophysical traverses



Figure 29: Macarthy traverses 1 and 2, EM and Mag



Figure 30: Macarthy traverse 3, EM and Mag



Figure 31: Roscoe traverse 1, EM and Mag



Figure 32: Roscoe traverse 2 and 3, Mag



Figure 33: Roscoe traverse 4, Mag



8.1.1 Drilling Recommendations

It is recommended that holes be drilled on or adjacent to the located structures. The exact

locations of the recommended drilling positions can be seen in Table 9 below. The boreholes will be

used for long term monitoring of water levels and the possible extension of the dewatering cone

towards the south. It is recommended that the boreholes be entirely cased, with perforated casing

from above the first water strike. The borehole must be constructed so as to comply with that of a

monitoring borehole.

Table 9: Location of proposed drilling sites for monitoring wells

Farm Location

Comments/Recommendations X Y

Roscoe Traverse 1 22.959499 -27.904714 Drill to 200 metres




Macarthy Traverse 3 23.050261 -27.910937 Drill to 200 metres




8.2 NEWLY PROPOSED MONITORING NETWORK

An investigation was carried out by Mr K. Vermaak in order to verify the previously proposed

monitoring network seen in Figure 27. It was discovered that many of the boreholes visited did not

fit the criteria necessary for the boreholes to be used as part of the monitoring network. The

boreholes listed below were found suitable to be used as part of the monitoring network.

The majority of the boreholes are located on the mine property and are to be monitored on a

quarterly basis. The newly drilled boreholes should be equipped with Leocell real-time monitoring

systems and are to be monitored on a daily basis. Rain gauges are to be installed with the Leocell

monitoring systems. Arrangements must be made with the farmers as necessary in order to gain

access to the relevant boreholes. Where applicable the farmer is not to use the borehole for any

pumping.

More boreholes will be added to the monitoring network based on the geophysical survey

conducted. The positions of these holes can be seen in Figure 34 with a summary of the network

information given in.Table 10.



Table 10: Summary of boreholes for monitoring network

Borehole

Location

Farm Farm Owner Parameter Frequency X Y

Wright 3 22.92230 -27.79459 Wright Stephanie

Cornellisen Water Levels Quarterly

SEK 0023 23.0705 -27.7235 Sekagame Khumba Water Levels Quarterly

BEST 2 23.09101 -27.68138 Bestwood Fred Viljoen Water Levels Quarterly

MOK 2 23.04974 -27.91066 Mokaning Nic Steyn Water Levels Quarterly

Mashwenin 23.0485 27.88725 - Assmang Water Levels Quarterly

Mashwenin 23.0566 27.89595 - Assmang Water Levels Quarterly

Mokaning 1 23.0296 27.88651 - Assmang Water Levels Quarterly

Mokaning 2 23.0351 27.89274 - Assmang Water Levels Quarterly

King 3 22.9954 27.8496 - Assmang Water Levels Quarterly



BKM 1 23.0146 27.77299 - Assmang Water Levels Quarterly

BKM 3D 22.991 27.88483 - Assmang Water Levels Quarterly

PBW 01 22.9693 27.84925 - Assmang Water Levels Quarterly

Parsons1 22.9848 27.85842 - Assmang Water Levels Quarterly



AGK2/87 22.9868 -27.8875 - Assmang Water Levels Quarterly

AIK1/45 23.0011 -27.8858 - Assmang Water Levels Quarterly

VK2/81 22.9837 -27.8695 - Assmang Water Levels Quarterly

VK1/49 22.9827 -27.8677 - Assmang Water Levels Quarterly

WK2/35 22.9959 -27.8672 - Assmang Water Levels Quarterly

QK4/55 22.9959 -27.8636 - Assmang Water Levels Quarterly



ZR3/24 23.0208 -27.808 - Assmang Water Levels Quarterly

ABK2/42 22.9944 -27.8767 - Assmang Water Levels Quarterly

ZR3/2 23.0198 -27.8072 - Assmang Water Levels Quarterly



Borehole

Location

Farm Farm Owner Parameter Frequency X Y

AMK1/47 22.9923 -27.8943 - Assmang Water Levels Quarterly

AGK1/89 22.9832 -27.8871 - Assmang Water Levels Quarterly

AAK2/45 22.9862 -27.8763 - Assmang Water Levels Quarterly

WK4/70 22.999 -27.8728 - Assmang Water Levels Quarterly

VK3/67A 22.9822 -27.8727 - Assmang Water Levels Quarterly

KM3/24 23.0005 -27.8893 - Assmang Water Levels Quarterly

ALK3/22 22.9796 -27.8979 - Assmang Water Levels Quarterly

AKK4/26 22.9761 -27.8984 - Assmang Water Levels Quarterly

ABK2/46 22.9964 -27.8767 - Assmang Water Levels Quarterly

AAK3/27 22.9817 -27.8803 - Assmang Water Levels Quarterly

ALK2/49 22.9878 -27.8948 - Assmang Water Levels Quarterly

PBE01 22.9836 -27.8513 - Assmang Water Levels,

Chemistry Quarterly

PBW01 22.9617 -27.843 - Assmang Water Levels,

Chemistry Quarterly


Chemistry Quarterly


Chemistry Quarterly


Chemistry Quarterly

BKM1 23.0146 -27.7731 - Assmang Water Levels Quarterly

BKM2 23.0185 -27.847 - Assmang Water Levels,

Chemistry Quarterly

BKM3D 22.9793 -27.8777 - Assmang Water Levels Quarterly

BKM4 23.0265 -27.8674 - Assmang Water Levels Quarterly



Figure 34: Newly proposed monitoring network excluding holes located during geophysics



8.3 WATER LEVELS WITHIN THE MINE BOUNDARY

Upon further investigation of the water levels within the mine area it was discovered that a large

difference in water levels was apparent. Water levels to the east are deeper than those in the west.

This difference in water levels can be attributed to a possible north-south striking structure. The

difference in water levels can be seen in Figure 35 below.

The extent of the structure is not known. The water levels in its vicinity are to be monitored closely

in the boreholes adjacent to the suspected structure so as to confirm its compartment forming

characteristics.

8.4 SURFACE WATER MONITORING

8.4.1 Water quality

The in-stream water quality must be analysed during flow periods at the monitoring points

mentioned under condition 3.2.1 for the variables: pH, electrical conductivity (mS/m), suspended

solids (mg/ℓ), and total dissolved solids (mg/ℓ).

The draft water licence recommends that flow meters be installed where the river intersects the

mine boundaries.

8.4.2 Monitoring

Monitoring points for the water quality monitoring must be identified in consultation with the

Department, upstream and downstream of each of the river crossings and the conveyor belt.

8.4.3 Method of analysis

Analysis shall be carried out in accordance with methods prescribed by and obtainable from the

South African Bureau of Standards (SABS), in terms of the Standards Act, 1982 (Act 30 of 1982).

The methods of analysis shall not be changed without prior notification to and written approval by

the Minister.

8.4.4 Reporting

Water quality report shall be submitted to the Regional Director on an annual basis under reference

number 16/2/7/D41J/A1.

8.4.5 Storm water management

Storm water shall be diverted from the construction works and roads and shall be managed in such a

manner as to disperse runoff and concentrating the storm water flow.

Where necessary, works must be constructed to attenuate the velocity of the storm water discharge

and to protect the banks of the watercourse.

Storm water control works must be constructed, operated and maintained in a sustainable manner

throughout the project.

8.5 MONITORING FREQUENCY

The frequency of monitoring at the site will be based on requirements set out in the draft water

licence although is recommended that the monitoring frequency be revised and that monitoring only

take place on a quarterly basis

The quantity of water removed during mining activities must be measured as follows:



i. The daily quantity of water removed must be metered or gauged and the total

recorded at the last day of each month; and

ii. The licensee shall keep record of all water removed and a copy of the records shall be

forwarded to the Chief Director on a monthly basis.

Groundwater monitoring must be done on all relevant boreholes on the mine as indicated in the

Water Use Authorisation Report Volume 1 and 2 of February 2006 on a three monthly basis.

Water level monitoring must be done at all new and proposed monitoring boreholes on a

quarterly basis.

Abstraction must be monitored on a daily basis.

Water quality monitoring must initially be done at all of the monitoring boreholes on a quarterly

basis until sufficient baseline data are available to justify a new monitoring schedule.

8.6 MONITORING PARAMETERS

The identification of the monitoring parameters is crucial and depends on the chemistry of possible

pollution sources. The monitoring parameters are stipulated in the draft water licence. They

comprise a set of physical and/or chemical parameters (e.g. groundwater levels and predetermined

organic and inorganic chemical constituents). The specific requirements as stipulated in the draft

licence can be seen in Table 11.

8.6.1 Full analysis

Physical Parameters:

Groundwater levels

Rainfall must be monitored at least at two sites of the mine on a continuous hourly basis.

Chemical Parameters:

Field measurements:

pH, EC

Laboratory analyses:

Anions and cations (Ca, Mg, Na, K, NO3, Cl, SO4, F, Si, Fe, Mn, Al, Zn, & Alkalinity)

Other parameters (pH, EC, TDS)

Petroleum hydrocarbon contaminants (where applicable near workshops and petroleum

handling facilities)

Sewage related contaminants (COD, PO4, E.Coli, faecal coliforms) (where applicable).



Table 11: Water Licence Requirements for the Groundwater Qualities

pH 8.3

Electrical Conductivity (mS/m) 115.6

Total Dissolved Solids (mg/ℓ) 827

Calcium as Ca (mg/ℓ) 93.8

Magnesium as Mg (mg/ℓ) 70.4

Sodium as Na (mg/ℓ) 60.0

Potassium as K (mg/ℓ) 4.9

Chloride as Cl (mg/ℓ) 140.5

Total Alkalinity as CaCO3 (mg/ℓ) 364.8

Sulphate as SO4 (mg/ℓ) 80.6

Nitrate as NO3 (mg/ℓ) 14.8

Fluoride as F (mg/ℓ) 0.5

8.7 INADEQUACIES OF THE MONITORING NETWORK

Currently no groundwater monitoring is done concerning hydrocarbon analysis at the workshops

(petroleum hydrocarbon contaminants) as this is not considered a high priority area. A borehole(s)

should be drilled in this area to identify the impact that the activities have on the groundwater in

the area. It is important to concentrate on the high priority areas such as source areas with

shallower water tables.

Some areas have not been covered in terms of monitoring, due to lack of access to the neighbouring

Kumba mine. Sharing of data between Kumba and Khumani mines will result in a complete

monitoring network and will benefit both parties concerned.

It is recommended that the draft water licence, water quality requirements be revised and set in

line with SANS standards. pH, EC and major cations and anions are to be analysed. These include

Ca, Mg, Al, Mn, Cl, Na, Fe, F, SO4, Nitrate as N, Ammonia as N and Alkalinity.



Figure 35: Water levels indicating possible structure



9 GROUNDWATER RELATED ENVIRONMENTAL MANAGEMENT PLAN (EMP)

Water quality and quantity monitoring form an important part of the EMP at Khumani Mine. The

quality and quantity are to be monitored according to the stipulations set out according to the draft

water licence. Due to the young age of the mine the initial monitoring results will act as a baseline

study for future reference.

A summary of the proposed EMP is given in Table 12 and Table 13. It is important to monitor static

water levels in all allocated boreholes within the specified zone to monitor any deviation of the

groundwater levels. Water levels, pump rates and rainfall should be recorded according to the draft

water licence requirements to establish a record of drawdown and thus act as an early warning for

aquifer depletion. All data recorded in this way should be analysed by a professional hydrogeologist

If it can be proven that the operation is indeed affecting the quantity of groundwater available to

certain users, the affected parties may be compensated. The details of this issue should comply

with the draft water licence. This may be done through the installation of additional boreholes for

water supply purposes, or an alternative water supply.

Water samples must be taken from the selected monitoring boreholes on a quarterly basis by using

approved sampling techniques and adhering to recognised sampling procedures. The monitoring

system is discussed in detail in the section below. These results should be recorded on a data sheet.

It is proposed that the data should be entered into an appropriate computer database and reported

to the Department of Water Affairs.



Table 12: EMP Summary � Water Quality Management

ACTIVITY OBJECTIVES MITIGATION INTENDED ACTIONS RESPONSIBLE PERSON

Water

quality

management

Determine the impact

of the activities at

Khumani on the

groundwater

environment.

Contain pollution as

far as is practicably

possible on the mine

property.

Reduce the level of

contamination

outside the mine

boundaries.

Continue with the

groundwater monitoring

programme.

Monitor the water quality and water levels of the

sampling points as mentioned in section 7.

Audit the monitoring network annually.

Maintain and repair groundwater water monitoring

network.

Assess groundwater water quality at workshops and

other petroleum hydrocarbon related activities.

Environmental Officer

Appropriate mitigation

measures should be

implemented (where

applicable) in the areas

of concern

Any deterioration in the water quality indentified by

the monitoring can be discussed with the landowner,

if required.

Infrastructure should be designed and constructed in a

way so as to minimise the impacts on the

environment.


General Address the concerns and complaints of affected

parties regarding the groundwater issues.

All remedial action should be done in close liaison

with the Department of Water Affairs.

The liabilities and proposed preventative and

remedial actions will also have to be quantified.




Table 13: EMP Summary � Water Quantity Management

ACTIVITY OBJECTIVES MITIGATION INTENDED ACTIONS RESPONSIBLE PERSON

Water

quantity

management

Determine the impact of

the activities at

Khumani on the ground

water levels.

Monitor groundwater

levels. Monitor water levels of the sampling points as

mentioned in section 7.

Installation of real-time monitoring system at

specified boreholes.

Audit the monitoring network annually.

Maintain and repair groundwater water monitoring

network.


Appropriate mitigation

measures should be

implemented (where

applicable) in the areas

of concern.

Any deterioration in the water quantity indentified by

the monitoring must be discussed with the landowner,

where required.

Revision of monitoring network.

Water supply to affected users where applicable.

(Infrastructure may be put into place to supply

affected users adequately.)


General Address the concerns and complaints of affected

parties regarding the ground water issue.

All action to be carried-out in close liaison with the

Department of Water Affairs.




10 CONCLUSIONS AND RECOMMENDATIONS

From the study done on the area, it has become clear that dewatering had occurred before the

initiation of mining at Khumani mine and that some farmers have been affected. Khumani has not

yet intersected the water table during its mining activities. Due to the aquifers being previously

dewatered, the intersection of the water table will take longer than if no previous abstraction had

taken place.

It has become apparent that the effects of compartmentalisation are in effect in the project area,

these effects are to be monitored closely. A north�south striking structure runs through the mine

property and forms a barrier, where the differences in water levels can be seen. This is more

evidence that the effects of compartmentalisation are in effect. The permeabilities of the

structures forming these compartments are questionable as faulting and weathering can

compromise the permeabilities.

A monitoring network was set for the area based on DWA data. A verification of this network was

carried out and it was found that the data were unreliable or that access to the properties was

restricted. Due to this, the original proposed monitoring network had to be abandoned. A new

monitoring network was established and additional drilling targets were sited for addition to the

network. The monitoring network will monitor the effects of abstraction and will also act as

baseline data for future reference. The boreholes located on or adjacent to structures will monitor

the effect of the structure on the water levels. It is recommended that a water level database be

established and kept up to date. This will facilitate easy access to data at all times.

It is advised that the frequency of the water level monitoring be adjusted to quarterly instead of

monthly, as stipulated in the draft water licence. Leocell monitoring systems are to be installed in

the newly drilled boreholes so as to monitor the southern extent of the dewatering.

In order to gain a better and more complete understanding of the geohydrological situation of the

area, it would be ideal that an agreement is reached between Kumba and Khumani. This will

facilitate the construction of a more accurate conceptual model.

The water quality in the area is within acceptable SANS standards. Although the chemistries of

numerous boreholes are above those that have been stipulated in the draft water licence, it is

recommended that the standards in the draft licence be adjusted to the SANS standards in order to

have one uniform standard.

Documents

FOR - GCS...Compiled For: Assmang Iron Ore Compiled By: K.H. Vermaak(M.Sc.) GPT Reference: Kum-09-403 Version: Final Version 1.0 Date: June 2010 Distribution List (Current Version):