surface water assessment for the magdalena colliery discard … · 2015. 9. 29. · 4a old main...

4a Old Main Road, Judges Walk, Kloof, Kwazulu-Natal South Africa 3610

PO Box 819 Gillitts 3603 South Africa

Telephone: +27 (0)31 764 7130 Facsimile: +27 (0)31 764 7140

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Surface Water Assessment for the Magdalena

Colliery Discard Dump Extension

Version – V1

10 November 2013

For: Zinoju Coal (Pty) Ltd

GCS Project Number: 12-094

Zinoju Coal (Pty) Ltd Magdalena Colliery Discard Dump Extension

12-094 10 November 2013 Page ii

Surface Water Assessment for the Magdalena Discard Dump extension

Final

10 November 2013

For: Zinoju Coal (Pty) Ltd

DOCUMENT ISSUE STATUS

Report Issue Final

GCS Reference Number GSC Ref- 12-094

Title Hydrological Assessment for the Magdalena Colliery Discard Dump

Extension

Name Signature Date

Author

Nhlakanipho Zondi

09 September 2013

Document Reviewer Phillip Lourens

01 November 2013

Director Pieter Labuschagne

05 November 2013

LEGAL NOTICE

This report or any proportion thereof and any associated documentation remain the property of GCS until the

mandator effects payment of all fees and disbursements due to GCS in terms of the GCS Conditions of Contract

and Project Acceptance Form. Notwithstanding the aforesaid, any reproduction, duplication, copying, adaptation,

editing, change, disclosure, publication, distribution, incorporation, modification, lending, transfer, sending,

delivering, serving or broadcasting must be authorised in writing by GCS.

EXECUTIVE SUMMARY


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Zinoju Coal (Pty) Ltd intends to extend their Discard Dump operation at the Magdalena

Colliery near Dundee KwaZulu-Natal. As part of an amendment to the existing

Environmental Management Programme (EMPR), GCS Water and Environmental (Pty) Ltd has

been commissioned by Zinoju Coal to conduct a hydrological assessment for the proposed

Discard Dump extension activities in order to understand the impact such activities will

have on site hydrology.

The following information were considered and evaluated:

• Rainfall, evaporation, and runoff;

• Surface water quality;

• Magdalena storm water management plan ; and

• Surface water monitoring.

The main findings can be summarised as follows:

• The mine is located in Water Management Area 7 uThukela in quaternary catchment

area V32D;

• The mine has a Mean Annual Rainfall of 791 mm;

• The mine experiences a Mean Annual Evaporation of 1 500 mm;

• The proposed Discard Dump site has Mean Annual Runoff of 0.00533 Mm3

• 10 of 16 surface water quality samples are within SANS standards;

• Water Balance of the mine needs to be updated to incorporate the Discard Dump

extension site.

• The Storm Water Management Plan of the mine indicates dirty storm water is

generated in two catchments:

o the discard dump and slurry dam area,

o the coal processing area, including the administration buildings and the

workshops;

• The surface water quality monitoring plan of the mine indicates compliance with

stipulations in the Environmental Management Plan.

The recommended way forward for the Magdalena Mine in terms of hydrology is summarised

as follows

• For the hydrology of the mine:


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o A GN704 audit;

o A site visit and detailed investigation into the surface water of the mine ;

and

o Surface water quality samples of Poonaspruit stream and process water on

the mine.


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GLOSSARY OF TERMINOLOGY

In this report any expression to which a meaning has been assigned, shall have the meaning

so assigned, and unless the context indicates otherwise-

Catchment - The area from which any rainfall will drain into the watercourse or

watercourses or part of the water course, through surface flow to a common point or

common points;

Activity- means any mining related process on the mine including the operation of washing

plants, mineral processing facilities, mineral refineries and extraction plants, and the

operation and the use of mineral loading and off-loading zones, transport facilities and

mineral storage yards, whether situated at the mine or not,

Clean water system- includes any dam, other form of impoundment, canal, works,

pipeline and any other structure or facility constructed for the retention or conveyance of

un-contaminate water;

Dam- includes any settling dam, slurry dam, evaporation dam, catchment or barrier dam

and any other form of impoundment used for the storage of unpolluted water or water

containing waste;

Dirty catchment- means any area at a mine or activity which causes, has caused or is likely

to cause contamination of a water resource;

Dirty water system- includes any dam, other form of impoundment, canal, works, pipeline,

residue deposit and any other structure or facility constructed for the retention or

conveyance of water containing waste;

Facility- in relation to an activity includes any installation and appurtenant works for the

storage, stockpiling, disposal, handling or processing of any substance;

Residue- includes any debris, discard, tailings, slimes, screenings, slurry, waste rock,

foundry sand, beneficiation plant waste, ash and any other waste product derived from or

incidental to the operation of a mine or activity and which is stockpiled, stored or

accumulated for potential re-use or recycling or which is disposed of;


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Residue deposit- includes any dump, tailings dam, slimes dam, ash dump, waste rock

dump, in-pit deposit and any other heap, pile or accumulation of residue;


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CONTENTS PAGE

1 INTRODUCTION .......................................................................................................................... 1

2 OBJECTIVES AND SCOPE OF WORK ............................................................................................. 2

2.1 OBJECTIVES .................................................................................................................................. 2 2.2 SCOPE OF WORK ............................................................................................................................ 2

3 METHODOLOGY ......................................................................................................................... 3

3.1 OVERVIEW OF RELEVANT LEGISLATION AND STANDARDS ....................................................................... 4 3.1.1 Legal Framework .............................................................................................................. 4

3.2 NATIONAL LEGISLATION .................................................................................................................. 5 3.3 NATIONAL POLICY/GUIDELINES ........................................................................................................ 5

4 LOCALITY .................................................................................................................................... 6

5 BACKGROUND INFORMATION .................................................................................................... 9

5.1 GEOLOGY ..................................................................................................................................... 9 5.2 CLIMATE ...................................................................................................................................... 9 5.3 TOPOGRAPHY ............................................................................................................................... 9 5.4 SURFACE WATER .......................................................................................................................... 10

6 DESCRIPTION OF SITE HYDROLOGY .......................................................................................... 11

6.1 RAINFALL ................................................................................................................................... 11 6.2 AVERAGE EVAPORATION................................................................................................................ 13 6.3 PEAK STORM RAINFALL ................................................................................................................. 14 6.4 SURFACE WATER RESOURCES AND CATCHMENT DELINEATION ............................................................. 14 6.5 CATCHMENT AREA AND DELINEATION.............................................................................................. 15 6.6 MEAN ANNUL RUNOFF ................................................................................................................. 17 6.7 CATCHMENT SLOPE AND TIME OF CONCENTRATION ............................................................................ 18 6.8 PEAK FLOWS AND VOLUMES .......................................................................................................... 19

7 WATER QUALITY ....................................................................................................................... 20

8 STORMWATER MANAGEMEMNT PLAN .................................................................................... 25

9 KEY ISSUES AND SCENARIOUS .................................................................................................. 26

9.1 CHANGES IN CATCHMENT CHARACTERISTICS ..................................................................................... 26 9.2 CHANGES IN PEAK FLOWS AND VOLUMES ......................................................................................... 26 9.3 CHANGES IN MEAN ANNUL RUNOFF ............................................................................................... 29 9.4 INCREASED SEDIMENT YIELD .......................................................................................................... 29

10 SURFACE WATER IMPACT ASSESSMENT ................................................................................... 30

10.1 CONSTRUCTION PHASE ................................................................................................................. 31 10.1.1 Surface water contamination ......................................................................................... 32 10.1.2 Siltation of surface water ................................................................................................ 32

10.2 OPERATIONAL PHASE ................................................................................................................... 34 10.2.1 Stream Peak flow Reduction ........................................................................................... 34

11 MONITORING PROGRAM ......................................................................................................... 38

12 GAP ANALYSIS .......................................................................................................................... 39

13 CONCLUSION ............................................................................................................................ 40

14 REFERENCES ............................................................................................................................. 42

LIST OF FIGURES

Figure 4-1: Zinoju Coal Operations Locality map ................................................ 7 Figure 4-2: Magdalena Discard Dump and Mine Boundary Overview ............................ 8


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Figure 6-1: Rainfall Station Close to Magdalena Area ............................................ 12 Figure 6-2: Average Rainfall Distribution ........................................................... 13 Figure 6-3: Magdalena Average Monthly Evaporation ............................................. 14 Figure 6-4: Magdalena Delineated Catchments .................................................... 16 Figure 7-1: Annual pH and sulphate for Surface Water site MS4a .............................. 21 Figure 7-2: Annual pH and sulphate for Surface Water site BOX ............................... 22 Figure 7-3: Magdalena Colliery Groundwater and Surface Water Monitoring Network ...... 23 Figure 7-4: Zoomed In Map Showing the Sectiion of Discard Dump Extansion and Monitoring Sites 24 Figure 9-1: Calculated Peak flows for the Bloubankspruit Catchment ........................ 27 Figure 9-2: Calculated Peak flows for the Catchement A ........................................ 27 Figure 9-3: Calculated Peak Volumes for the Bloubankspruit Catchement ................... 28 Figure 9-4: Calculated Peak Volumes for the Catchment A ..................................... 28

LIST OF TABLES

Table 5-1: Flood peaks and Volume for catchments at Magdalena Colliery ................. 10 Table 6-1: Rainfall Stations Considered ............................................................ 13 Table 6-2: Design 24 hour Peak Rainfall ............................................................ 14 Table 6-3: Catchment Area Sizes .................................................................... 15 Table 6-4: Baseline MAR before the Proposed Discard Dump Site ............................. 17 Table 6-5: Post Development Reduction in MAR .................................................. 17 Table 6-6: Baseline Catchment Characteristics ................................................... 18 Table 6-7 Baseline Flood Peaks and Volume ...................................................... 19 Table 6-8: Calculated Post Development Peak Runoff Flows and Volumes ................... 19 Table 10-1: Risk Assessment Significance Value .................................................... 30 Table 10-2: Risk Rating Matrix ......................................................................... 30 Table 10-3: Magdalena Construction Phase.......................................................... 33 Table 10-4: Magdalena Operational Phase Risk Assessment ...................................... 35 Table 10-5: Magdalena Closure Phase Risk Assessment ........................................... 36 Table 11-1: Monitoring Objectives According to EMP .............................................. 38

LIST OF APPENDICES

APPENDIX A: MAGDALENA 2ND

QUARTEYLY WATER MONITORING REPORT ................................... 43

APPENDIX B: MAGDALENA STORM WATER MANAGEMENT PLAN REPORT .................................... 44


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1 INTRODUCTION

Zinoju Coal (Pty) Ltd intends to extend the current Phase 3 operations at the Magdalena

Colliery to incorporate an extension to their existing discard dump. This proposal requires

that the approved Phase 3 Environmental Management Programme (EMP) be amended to

incorporate the proposed extension. As part of the EMP amendment, the GCS Water and

Environment (Pty) Ltd. (GCS) Water Unit was commissioned by Zinoju Coal to conduct a

surface water assessment for the proposed extension of the discard dump facility.

Zinoju Coal intends to expand the size of the Magdalena Colliery discard dump from 33

295.05m2(3.33ha) to 389 703.04m2 (38.97ha) (expansion of 356 407.98m2/35.64ha) in order

to accommodate the operational life of the company’s mining operations at the Magdalena

and Aviemore collieries.

The Magdalena Colliery is an existing coal mine that has been operational since 2003. The

existing mining area is operational under a number of Mining Rights, namely 227MR (Phase

1), 213MR (Phase 2) and 198MR (Phase 3) with corresponding approved Environmental

Management Programmes (EMPr’s) in accordance with the Mineral and Petroleum Resources

Development Act, 2002 (Act No. 28 of 2002) (MPRDA). In addition, an Integrated Water Use

License Application (IWULA) process for all existing water uses was completed in 2007.

The discard dump has been designed based on the planned life of mine during which discard

will be generated at a rate of 16 800 tonnes per month. A site selection process has been

followed and a preferred coal discard disposal facility was selected. GCS carried out a

preliminary geotechnical investigation at the preferred site.

As part of this amendment, a surface water assessment report; amongst other; is required

to identify any new potential impacts that may occur in addition to those identified in the

original EIA Report (ref) and inform and guide the selection of appropriate mitigation and

management measures.


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2 OBJECTIVES AND SCOPE OF WORK

The main focus of this assessment was to assess possible impacts on the surface water

environment; the following was required from this assessment:

2.1 Objectives

Update the existing hydrological baseline description for the mine;

• Determine and assess the potential surface water impacts associated with the

discard dump extension;

• Advise on mitigation measures for identified risks/impacts and enhance positive

opportunities/impacts of the project;

• Provide input to the WULA and NEMA documentation.

2.2 Scope of work

The Scope of Work (SoW) for the Hydrology Assessment is summarised as follows:

Phase 1:

• Information sourcing / literature review

• Collection and revision of relevant information

Phase 2:

• Site Visit

o Site assessment (better understanding of site) & quality sampling

• Update catchment hydrology with newly available data

o Catchment characteristics and delineation

o Meteorological analysis (including MAP)

o Average runoff analyses (MAR & NDWF)

o Peak flow analyses for 1:50 and 1:100 floods

o Analyses of all new and updated water quality samples and water level

monitoring data

• Updating Hydrology of the mine itself;


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o Review existing information and proposed water management strategies for

the mine;

o Undertake an impact assessment in accordance with GCS’s impact

assessment methodology;

o Identify monitoring mechanisms for implementing the suggested mitigation

measures;

o Provide the necessary supporting documentation for the WULA and NEMWA

applications.

3 METHODOLOGY

The following methodologies were used for the hydrological assessment of the catchment

that the mine is situated in:

A holistic approach was followed and an attempt was made to link local hydrological, water

quality and environmental studies to regional and national concerns, regulations and

management strategies.

A site visit was conducted in order to obtain information on normal flow rates, river health

and potential factors that could influence hydrological modelling of flows.

Generally accepted methods and formulae were used to determine design floods in the

relevant catchments. The following paragraph will briefly explain the Rational Method that

was ultimately used in the peak flow analyses:

Rational Method

The rational method was developed in the mid 19th century and is one of the most widely

used methods for the calculation of peak flows for small catchments.

The formula indicates that Q = CiA,

where Q is the peak flow, “i” is the rainfall intensity, A is the runoff area and C is the

runoff coefficient.


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Rainfall distribution is assumed to be uniform over small catchment areas of up to 15 km2.

A Time of Concentration (Tc) is calculated which represents the time it takes for rainfall to

contribute to runoff at the same discharge point of the catchment from all areas (even

furthest point) of the catchment. The slope of the catchment is used to determine Tc.

Average runoff from streams running through the site was calculated using accepted

techniques to downscale quaternary catchment data (WR2005).

Software employed in the study includes:

• ArcGIS10.1 (ESRI, 2012) for Geographic Information Systems (GIS) work and

• Design Rainfall Estimation package (Smithers and Schulze, 2003) for 24 design

rainfall depth;

The likely surface water impact associated with the planned mining development was

identified and possible mitigation measures were recommended to reduce the impacts

thereof.

3.1 Overview of Relevant Legislation and Standards

The entire process followed was guided by the following legislations

3.1.1 Legal Framework

DWA’s vision for water quality management in South Africa is to:

• ensure the continuous improvement of Water Quality Management

• become a recognized world leader in Water Quality Management

• be proactive, dynamic, efficient and effective in its delivery of services to the

public

• provide the necessary policies and systems to ensure integrated sustainable

management of water quality

• promote cooperative governance across all spheres of management and

• ensure a fully capacitated, loyal workforce to support its functions.


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3.2 National Legislation

National legislation applicable to surface water management includes:

• Constitution of the Republic of South Africa, 1996 (No. 108 of 1996) – The Bill of

Rights states that everyone has the right to an environment that is not harmful to

their health or well-being.

• National Water Act, 1998 (Act 36 of 1998) – Provides for the protection of the

quality of water and water resources in South Africa and provides for the

establishment of Water Management

3.3 National Policy/Guidelines

National policy and guidelines applicable to surface water management includes:

• South African Water Quality Guidelines, First Edition, 1996 – These guidelines set

out the minimum water quality requirements for a range of water quality

parameters for each water user.

• Development of a Waste Discharge Charge System: Framework Document. Second

Edition, 2000 – Provides a framework for the implementation of a system to charge

for water use such as the discharge of waste that impacts on water resources.

• Framework for a Water Quality Management Performance Assessment System:

(WQMPAS), First Edition, 2000 – Reports results on an initial investigation into a

performance management system to enable a more effective WQPMAS in future.

• Best Practice Guidelines for the mining sector, DWAF 2006, 2008 dealing with

aspects of DWA’s water management hierarchy and deals with integrated mine

water management, pollution prevention and minimisation of impacts, water reuse

and reclamation and water treatment.

• Best Practice Guidelines for the mining sector, DWAF 2006, 2008 dealing with

general water management strategies, techniques and tools which could be applied

cross – sectorial and deals with storm water management, water and salt balances,

water monitoring systems, impact prediction.


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• Best Practice Guidelines for the mining sector, DWAF 2006-2008 dealing with

specific mining activities and addresses the prevention and management of impacts

from small scale mining, water management for Mine Residue Deposits, pollution

control dams, water management for surface mines, and water management for

underground mines.

4 LOCALITY

The Magdalena Colliery is located approximately 22 km north of the town of Dundee, within

the Dannhauser Local Municipality and the Amajuba District Municipality in the KwaZulu-

Natal Province. The mine is located in Water Management Area 7 Thukela (WMA7) and in

quaternary catchment V32D. The mine locality map is shown in Figure 4-1.

Figure 6.2 shows the layout of the proposed discard dump extension in relation to the

current discard dump, underground workings and surface operations.


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Figure 4-1: Zinoju Coal Operations Locality map


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Figure 4-2: Magdalena Discard Dump and Mine Boundary Overview


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5 BACKGROUND INFORMATION

This section includes background information on the Magdalena Colliery Mine and the area

surrounding the mine. This was taken from the 2002 EMPR and will include information on

the Geology, climate and surface water for Bloubankspruit catchment within the W32D

quaternary catchment area.

5.1 Geology

The site consists of a series of horizontally layered sedimentary units of the Vryheid

formation located within the Ecca Group of the Karoo Supergroup. These sediments

comprise successions of sandstones, shales, mudstones, carbonaceous shales and coal

seams. The Ecca Group overlies rocks of the Dwyka Group.

5.2 Climate

The project area falls within the Newcastle, Vryheid and Dundee areas, the winters are

generally cold with average temperatures being 150C, extremes of down to –10OC. The

summers are warm to hot with the average temperatures of 27OC, but extreme high

temperatures of up to 40OC. The Mean Annual Precipitation (MAP) for the Dundee area is

791.3 mm. Mean wet season precipitation (October –April) is 702.9 mm and mean dry

season precipitation (May- September) is 88.4 mm. The mean annual “A-pan” evaporation

for the Newcastle area (1957 -1987) is 1 670.5 mm per year.

5.3 Topography

The area between the watershed and the escarpment edge is characterised by relatively

flat to steep terrain, with slopes varying from 0.76 to 15.2 %. The steep escarpment is

characterised by sparse grassveld vegetation, and a few shrubs and small trees. Runoff from

this area is likely to be high due to the shallow soils, steep terrain, and thin vegetation

cover.


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5.4 Surface water

The Magdalena colliery occurs within the upper catchments of the Poonaspruit and

Bloubankspruit. The streams are non-perennial and tributaries of the Buffels River. The

Bloubankspruit is 24.6 km2 in area with the MAR of 1.968 x106 m3 and Poonaspruit has an

area of 17.95 with the MAR of 1.436 x 106 m3. The calculated flood peaks and volumes for

the Poonaspruit and Bloubankspruit catchments are indicated in the table below.

Table 5-1: Flood peaks and Volume for catchments at Magdalena Colliery

Parameter Peak Discharge (m3/s) Peak Volumes (m3)

Catchment Area (km2) Area (Km2) Q50 Q100 QRMF V50 V100 VRMF

Poonaspruit catchment 17.95 63.6 77.8 142.7 11180 12300 35780

Bloubankspruit catchment 24.6 88.5 108.28 201.5 15330 16870 49060


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6 DESCRIPTION OF SITE HYDROLOGY

The original scope of works required that the existing hydrology of the proposed

development area be checked. In order to do so GCS performed a hydrological analysis of

the site. Results of previous hydrological analyses of the area are presented in section 5 of

this report.

6.1 Rainfall

Rainfall Data for the site was obtained from the WR2005 study (Middleton and Bailey,

2009), the Rainfall Extraction Utility Programme (Kunz, 2004) and the Design Rainfall

Estimation Program (Smithers and Schulze, 2002). The daily rainfall extraction utility

contains daily patched rainfall data for all official South African Weather Services stations.

The rainfall stations considered were close to the site, had a reasonable length of record

and a relatively complete and reliable data set. Please see Table 6-1 and Figure 6-1 below.

Dundee Pol. (0335400_W) was selected for use in the study. The station is located about

20km from the site at a similar altitude and thus represents local rainfall conditions.


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Figure 6-1: Rainfall Station Close to Magdalena Area


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Table 6-1: Rainfall Stations Considered

Station Number Station NameDistance from Site

(Km)

Start of

RecordEnd of Record

Number of

Years

Altitude

(mamsl)MAP

0335250W Glencoe 22.4 01-Apr-34 10-Sep-98 64 1322 837

0335400W Dundee Pol 20 01-Jul-33 31-May-00 67 1243 795

0370834W Ballangleigh 24 01-Aug-12 30-Jul-73 61 1228 858

0371150W Try Again 18 01-Aug-24 31-Jul-69 45 1433 760

0371706W Waaihoek 31.3 01-Jan-59 30-Jun-20 41 1355 676

0335520A Dundee Agric Res 26 01-Jan-31 13-Dec-82 46 1275 794

Monthly Rainfall data for the area are shown below. The mean annual precipitation for the

area is approximately 795mm. The average monthly distribution of this rainfall is shown in

the graph below.

Figure 6-2: Average Rainfall Distribution

6.2 Average evaporation

The Mean Annual Evaporation (MAE) for the site area according to the WR2005 database,

evaporation zone 21A is 1 500 mm. The average monthly distribution of this evaporation is

shown in the graph below.


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Figure 6-3: Magdalena Average Monthly Evaporation

6.3 Peak Storm Rainfall

The 24 hour storm rainfall depths described below for the 1:2, 1:5, 1:10, 1:20, 1:50 and

1:100 year recurrence intervals based on the data measured at the Dundee Pol. Rainfall

station, were extracted using the Design Rainfall Estimation package (Smithers and Schulze,

2003).

Table 6-2: Design 24 hour Peak Rainfall

Return Period 1:2 1:5 1:10 1:20 1:50 1:100

Rainfall Depth (mm) 62.4 83.4 97.8 112.1 131.4 146.2

6.4 Surface Water Resources and Catchment Delineation

The main hydrological feature on site is the Bloubankspruit non-perennial stream, which

flows from west to east across the catchment and drains to the Buffel River. Natural water

feature on site is a spring. Artificial water features include one storage dam used to

temporarily hold water from the slurry pond and four earth dams within the catchment.


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6.5 Catchment Area and Delineation

The baseline surface water assessment identified two sub-catchments affected by

Magdalena operation, see section 5 of this report. The Bloubankspruit sub-catchment is of

particular interest for this study being only affected by proposed discard dumb extension.

Bloubankspruit stream and non-perennial unnamed stream, a tributary to the

Bloubankspruit stream referred to as stream 1; were identified and used to delineate the

sub-catchments. The two sub-catchments are labelled and referred to as Bloubankspruit

and sub-catchment A and are representing natural drainage on the proposed site. The

existing and proposed discard dump extension site occurs within the upper catchment of

the Bloubankspruit. The Bloubankspruit catchment was reported to be 24.6 km2 in area

(EMPR 2002). Using the ArcGIS10.1 program the Bloubankspruit sub-catchment was

recalculated as 43.1 km2 in area and the sub-catchment A was 8.73 km2. The sub-

catchments are shown in the Figure 6-4 below. Table 6-3 shows the summary sub-

catchment nomenclature adopted for this report.

The sub-catchments are largely rural with a few, isolated residential properties and one

storage dam along the non-perennial stream running on catchment A and four storage dams

within Bloubankspruit sub-catchment

Table 6-3: Catchment Area Sizes

Catchments

Total surface area size

(km2)

WMA 7

29 046

Quaternary catchment W32D

590

Bloubankspruit sub-catchment

43.13

Sub-catchment A

8.73

The natural vegetation of the two sub-catchments are similar and characterised by

grasslands, some areas of trees (natural trees) and light bush.


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Figure 6-4: Magdalena Delineated Catchments


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6.6 Mean Annul Runoff

The baseline surface water study (2001 EMPR), indicates a Mean Annual Runoff (MAR) of

1.968 Mm3 for the Bloubankspruit sub-catchment .The WR2005 runoff data indicates a

(MAR) of 28.21 Mm3 for the quaternary catchment area V32D.

WR2005 quaternary runoff data (Middleton and Bailey, 2009) were downscaled in order to

obtain representative post development site runoff. The MAR for the Bloubankspruit sub-

cathcment and the proposed discard dump site were calculated by multiplying monthly

runoff values obtained from the WR2005 database (Middleton & Bailey, 2009) by a

correction factor. This factor was calculated by multiplying the quotient of the site area

and the quaternary catchment area, raised to the power of 2.6, by the quotient of the site

rainfall and the quaternary catchment rainfall. The resulting MAR values are tabulated

below. Table 5-4 illustrates the Baseline MAR in the context of the quaternary catchment,

whilst Table 10 presents the Anticipated reduction in MAR as a consequence of the discard

dump expansion.

Table 6-4: Baseline MAR before the Proposed Discard Dump Site

Sub-

Catchment

Quaternary

Catchment

Quaternary

Catchment

Area (km2)

Quaternary

Catchment

MAR (x106 m

3)

Sub-

Catchment

MAR (x106

m3)

Sub-

Catchment

Contribution

to MAR %

Bloubankspruit V32D 590 28.215 2.6 9

Catchment A V32D 590 28.215 0.5 1.8

Table 6-5: Post Development Reduction in MAR

Sub-Catchments

Post Development Sub

Catchment MAR (x106

m3)

Reduction in Sub-

Catchment MAR (%)

Sub-Catchment

Contribution to MAR (%)

Bloubankspruit 2.43 6.5 8.6

Catchment A 0.47 6 1.7


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It is anticipated that the proposed discard dump will affect the nature of the sub-

catchments and alter the rainfall runoff response. Anticipated changes are presented in

Table 6-5 above. It should be noted that the effective sub-catchment areas are significantly

reduced due to the assumed capture, retention and reuse of rainfall within the designated

“dirty” area. These include the two designed return water dams located north to the

existing dump and south to the proposed extension. Also the old open pit north of the

existing dump will be used as a return water dam.

6.7 Catchment slope and Time of Concentration

The slope of a catchment is a very important characteristic in the determination of flood

peaks. Steep slopes cause water to run faster and to shorten the critical duration of flood

inducing storms, thus leading to the use of higher rainfall intensities in the runoff formulae.

On steep slopes the vegetation is generally less dense, soil layers are shallower, and there

are fewer depressions, all of which cause water to run off more rapidly. The result is that

infiltration is reduced and flood peaks are consequently even higher. The average

catchment slope (SA) for the two sub-catchments under consideration are presented in

Table 6-6 below.

Table 6-6: Baseline Catchment Characteristics

Sub-Catchments Area (km

2) L (km) SL (m/m) SA (m/m) Tc (h)

Bloubankspruit 43.13 13.73 0.052 0.73

0.5622

Catchment A 8.73 4.76 0.011 0.18

0.428

Main watercourse slopes (SL) were determined using the 1085 method developed by The US

Geological Survey. This method has been found to yield accurate results for relatively small

catchments such as these.

The time that a water particle requires to travel from the furthest point in the catchment

to the outlet is known as the time of concentration. The time of Concentration can consist

of natural stream flow and overland flow components. Table 6-6 illustrates the baseline

catchment characteristics that affect the time of concentration.


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6.8 Peak flows and Volumes

The baseline Peak flows for the Bloubankspruit sub-catchment were determined in the 2002

EMPR, refer to section 5 of this report. Since new Bloubankspruit catchment area was

calculated and adapted for this study, the peak flows and volume were also necessary to be

update.

Peak flows can be estimated by using empirical, statistical and deterministic methods.

Empirical methods have not been used, as they are recommended for areas lager than 100

km2 (with caution for area lager than 10 km2). Calculated 1:50 and 1: 100-year storm peak

flows were determined using the rational method.

The Peak volumes were calculated for the 1:50 and 1:100-year return periods using the

calculation: Volume (m3) = 0.5*(3*Tc (sec))* Qp, from the South African National Roads

Agency Drainage Manual (SANRAL, 2007).

Table 6-7 illustrate the calculated baseline peak runoff flows and volumes for the two sub

catchments for the 50 and 100-year storm events.

Table 6-7 Baseline Flood Peaks and Volume

Sub-Catchments Q50 Q100 V50 V100

(m3/s) (X10

6m

3)

Bloubankspruit 967.49 1205.31 2.94 3.66

Catchment A 131.85 216.63 0.31 0.55

Table 6-8 demonstrates the likely effect of the proposed development on peak flows and

Runoff volumes for the proposed post mitigation. The slightly lower post mitigation flows

are largely attributable to the reduction in effective catchment area due to the expansion

of discard dump and construction of the return water dam.

Table 6-8: Calculated Post Development Peak Runoff Flows and Volumes

Sub-Catchments

Q50 Q100 V50 V100

(m3/s) (X10

6m

3)

Bloubankspruit 958.7 1194.4 2.91 3.62

Catchment A 126 207 0.29 0.48


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7 WATER QUALITY

A water quality baseline assessment was initiated by GEOVICON cc in 2001. Thereafter,

Zinoju Coal had established the monitoring network for both Surface and groundwater.

Samples were collected by a delegated person from Zinoju Coal and were sent to Yanka

Laboratories in Mpumalanga for analysis.

This section describes the surface water quality at the mine as represented in a quarterly

water monitoring report (Magdalena 4th Quarterly Water Monitoring Report, GCS Water and

Environmental (Pty) Ltd, 2012). Also please see the full report in Appendix A.

All monitoring points that have been sampled were compared to the SANS 241-1 domestic

water use quality standards (SABS, 2011). The following parameters have been analysed in

each sample:

- pH;

- Electrical Conductivity (EC) (mS/m);

- Calcium (Ca) (mg/l);

- Magnesium (Mg) (mg/l);

- Sodium (Na) (mg/l);

- Sulphate (SO4) (mg/l);

- Iron (Fe) (mg/l); and

- Manganese (Mn) (mg/l).

A total of 16 samples are monitored and their geographic locations can be seen in the

detailed report, please see Appendix A).

The proposed discard dump extension will generally drain to the eastern tributaries of the

Bloubankspruit stream. For this study sample points MS1, MS2 and MS3 will give the

indication of the baseline water quality for the pre-expansion of the proposed discard

dump. The results of sample points at MS1 and MS2 were dry during the first monitoring.

MS3 had high conductivity, calcium, magnesium, iron, dissolved organic carbon and faecal;

Colliform content exceeding SANS 214:1 domestic water standard limits.


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The following paragraphs briefly describe the laboratory results of 6 out 16 sample

locations with bad quality:

• MS4a, BOX, BUL, FD1, FD2 and SPRING all have high conductivity, TDS, sodium and

sulphate concentrations, exceeding the maximum allowable SANS water quality

limits. SPRING and BOX also have high manganese concentrations;

• Figure 7-1 shows a general increase in sulphate concentrations at MS4a with a

relatively stable pH over the same time period which is a result of surface water

and stormwater management problems. This could also be a result of shallow

aquifer seepage as baseflow into the stream;

Figure 7-1: Annual pH and sulphate for Surface Water site MS4a

• Figure 7-2 shows the sulphate versus pH levels at BOX. Sulphate levels has generally

increased over time whilst pH has remained relatively stable, with the exception of

a period in 2009 in which pH levels dropped significantly resulting in a concurrent

spike in sulphate levels. Poor water quality is a result of pumping water from the

slurry pond into BOX to reduce the water levels in the slurry pond.


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Figure 7-2: Annual pH and sulphate for Surface Water site BOX In Conclusion:

• Many of the surface water points were dry as a result of the recent drought; and

• No acidic pH conditions were evident from any of the surface water sites.


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Figure 7-3: Magdalena Colliery Groundwater and Surface Water Monitoring Network


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Figure 7-4: Zoomed In Map Showing the Sectiion of Discard Dump Extansion and Monitoring Sites


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8 STORMWATER MANAGEMEMNT PLAN

Effort has been made by the mine to separate clean and dirty water on site. The paragraphs

below detail the conceptual Storm Water Management Plan (SWMP) supplied to the

consultant by the mine (Magdalena Storm Water Management Plan report, iLanda Water

Services, August 2011. Please see the full report in Appendix B.

Clean and Dirty Catchment Identification and Separation

• Storm water generally flows from west to east across the Magdalena Colliery site.

• Clean storm water is generated to the west of the Colliery.

• Dirty storm water is generated in two areas:

o the discard dump and slurry dam area

o the coal processing area, including the administration buildings and the

workshops;

• The proposed Discard Dump workings at Magdalena Colliery is planned to be

operational approximately for 14 months, (communication with Frank Talbot);

• The storm water management infrastructure requirements should be incorporated

into the operation and rehabilitation works of the discard dump;

• The slurry dam, discard dump, the coal washing and processing facilities will

remain operational for the foreseeable future. The Storm water diversion channels

are required to the west of these facilities. These diversion channels will divert

clean storm water around the facilities and discharge the storm water to the east

of the facilities;

• Two adits to the underground workings will remain operational. These are located

in two sections of the current Discard Dump workings. The pits and access ramps

that currently serve the two adits will remain in place. Storm water will be

directed around these pits.

Please see a detail report in Appendix B.


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9 KEY ISSUES AND SCENARIOUS

From a hydrological perspective, the following key issues have been identified. These issues

are discussed below, while their impact and possible mitigating measures are discussed in

the following section.

9.1 Changes in Catchment Characteristics

The catchment characteristics of Bloubankspruit sub-catchment will be altered by the

proposed extension. The discard dump has been classified as “dirty” in terms of the DWA

Best Practice Guideline (BGP). Every effort must be made to separate clean and dirty area

by containing runoff from “dirty” areas.

Surface water runoff from the discard dump area should be collected and contained in

order to ensure the following objectives are met:

• Minimisation of contaminated areas and reuse of dirty water (where possible)

• Minimisation of seepage from the discard facility

• Prevention of overflows and minimization of seepage losses from storage facilities

(pollution control dams) Prevention of further deterioration of water quality.

Being dirty, surface water emanating from the discard dump would be captured as close as

possible. The return water dam would also cause an increase in hydrologically ineffective

areas. Consequently, the calculated flood peak values and MAR would decrease as shown in

Table 6-8

9.2 Changes in Peak flows and Volumes

The baseline and anticipated post-development peal runoff flows and volumes calculations

are illustrated in section 6 of this report. This section assess the key issues associated with

these changes whilst the impact on surface water follows in section 10


12-094 Page 27

The graphs below shows the effect of change in the Bloubankspruit and sub-catchment A on

the 50 and 100-year peak flows and 50 and 100-year flood volumes. It is evident that impact

on Bloubankspruit sub-catchment is not severely impacted and a comparison between the

baseline and post development figures show an average net decrease of roughly 1 % in both

peak flow and volume, these changes are negligible.

Figure 9-1: Calculated Peak flows for the Bloubankspruit Catchment

Figure 9-2: Calculated Peak flows for the Catchement A


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Figure 9-3: Calculated Peak Volumes for the Bloubankspruit Catchement

Figure 9-4: Calculated Peak Volumes for the Catchment A


12-094 Page 29

9.3 Changes in Mean Annul Runoff

It is evidence from the MAR values in Table 6-5 that the proposed discard dump effect

would not be significant on Bloubankspruit sub-catchment. The impact of this change on

surface water follows in section 10 of this report. The Post development MAR would be

0.47m3 per annum. This quantity of water would be contained the two PCDs. The reduction

in MAR quaternary catchment would be in order of 0.2%, which would be negligible.

However the reduction in MAR for the Bloubankspruit would be about 8.6%. The findings in

section 6 verify that there would be no noticeable impact on the quaternary catchment

V32D.

9.4 Increased Sediment Yield

The construction of haul roads and transport of discard material would increase the

quantity of airborne sediments. This dust would settle of the ground surface where it would

present additional sediments during rainfall events. The impact of this change in surface

water follows in Section 10 of this report.


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10 SURFACE WATER IMPACT ASSESSMENT

This exercise of risk identification and mitigation involves identification of streams found

downstream of the proposed development, as well as a description of the identified risks

the environment may incur during the various phases of the project.

The risk rating matrix methodology used is based on the following quantitative measures:

• The probability of impact occurrence;

• The frequency of impact occurrence;

• The special extent of impact occurrence;

• The intensity of impact occurrence; and

• Duration of impact occurrence.

The ratings to be assigned are presented in Table 10-2. The ratings are then combined to

determine the risk significance points for the impact according to the following equation:

Risk significance value = (magnitude + duration + intensity + frequency) x probability

The maximum value is 18 risk points and ratings are scaled from high, medium to low in

respect to their environmental impact. The ranking system used in the study is presented in

Table 10-1.

Table 10-1: Risk Assessment Significance Value

The maximum value that can be achieved is 100 Significance Points (SP). Environmental effects were rated as follows:

Significance Environmental Significance Points Colour Code

High (positive) >60 H

Medium (positive) 30 to 60 M

Low (positive) <30 L

Neutral 0 N

Low (negative) >-30 L

Medium (negative)

-30 to -60 M

High (negative) <-60 H

Table 10-2: Risk Rating Matrix


12-094 Page 31

Status of Impact

+: Positive (A benefit to the receiving environment)

N: Neutral (No cost or benefit to the receiving environment)

-: Negative (A cost to the receiving environment)

Magnitude:=M Duration:=D

10: Very high/don’t know 5: Permanent

8: High 4: Long-term (ceases with the operational life)

6: Moderate 3: Medium-term (5-15 years)

4: Low 2: Short-term (0-5 years)

2: Minor 1: Immediate

0: Not applicable/none/negligible 0: Not applicable/none/negligible

Scale:=S Probability:=P

5: International 5: Definite/don’t know

4: National 4: Highly probable

3: Regional 3: Medium probability

2: Local 2: Low probability

1: Site only 1: Improbable

0: Not applicable/none/negligible 0: Not applicable/none/negligible

10.1 Construction Phase

Most of the required infrastructure is already in place and has been previously assessed

under the existing and approved EMP (GCS, 2008). However, the proposed discard dump

extension will result in new areas being disturbed.

The construction phase consists of the following activities:

• Footprint area clearance.

• The maintenance and upgrading of the total clean water and dirty water diversion

trenches; and

• Handling of truck fuel and oil spills.

The potential impacts of the project during the construction phase before and after

mitigation are listed and ranked in Table 10-3.


12-094 Page 32

10.1.1 Surface water contamination

Truck oils and fuel could lick and spill to water resources. All oils and fuels must be stored

in banded areas and any spillages must be managed immediately in accordance with the

Emergency Response plan. The emergency response plan must be provided by contractors.

This will reduce the risks from High to low

The current discard dump could be disturbed and cause instability resulting in more

seepage to surface water resources. Any seepage must be contained according to design

criteria. The berms must be constructed upslope of the footprint area to divert clean water

to the discard dump and dirty water emanating from the dump should be captured and

contained. This will reduce the risks from high to low.

10.1.2 Siltation of surface water

Footprint clearance will expose soil. Prior to construction; clean and dirty separation

infrastructure need to be in place to manage runoff velocity preventing erosion gullies. The

Risk will be reduced from high to low.


12-094 Page 33

Table 10-3: Magdalena Construction Phase

M D S P

TOTAL

STATUS

SP M D S P

TOTAL

STATUS

SP

Siltation of surface water

resources & associated soil erosion

Footprint Clearance &

Construction - exposed soil10 4 3 5 85 - H

Ensure that clean and dirty water

separation infrastructure is in place prior

to the commencement of construction.

4 4 1 2 18 - L

Reduced runoff to surface water

resources & potential

contamination due to incorrect

dam sizing

Construction - SWMP

measures diverted runoff10 4 2 5 80 - H

Minimise the dirty water area. Appropriate

SWMP 1:50 year storm event to be

contained and re-used water in plant

processing.

6 1 1 3 24 - L

Waste Handling - fuel and oil

spills6 3 3 3 36 - M Prevent spillage of fuel and oils. 4 3 2 2 18 - L

Waste Handling - Seepage to

surface water resources from

disacard dump area

10 4 2 5 80 - H

Design criteria should prevent seepage

(Refer the Magdalena Discard dump design

and Hydrogeological study). Any seepage

must be contained.

6 4 1 2 22 - L

CONSTRUCTION PHASE ACTIVITIES: SITE PREPARATION and FOOTPRINT CLEARANCE

MAGDALENA MINING AREAS: 1.EXISTING DICARD DUMP and EXPANSION DISCARD DUMP

SURFACE WATER

Dicard Dump Expansion

Surface water contamination

POTENTIAL ENVIRONMENTAL

IMPACT

APPLICABLE

MAGDALENA MINE

AREA

ACTIVITY

ENVIRONMENTAL SIGNIFICANCE

BEFORE MITIGATION

RECOMMENDED MITIGATION MEASURES


AFTER MITIGATION


12-094 Page 34

10.2 Operational Phase

During the operational phase, coal will be mined and processed in the crushing and

screening plant. The coal will be washed and transported by truck to the stockpile area

after processing. The associated residue will be disposed of at the discard dump facility.

The Operational phase consists of the following activities:

• Dirty runoff from the discard;

• Exposure of soil surface and ineffective rehabilitation; and

• Discard dump risk of failure

The potential impacts of the project during the operation phase before and after mitigation

are listed and ranked in Table 10-4.

10.2.1 Stream Peak flow Reduction

The discard dump extension will reduce the Bloubankspruit and sub-catchment A areas and

runoff volumes. The baseline MAR for Bloubankspruit and sub-catchment A were modelled

as 2.3Mm3 and 0.5Mm3. The post-development discard dump extension site runoff was

modelled at 0.47 Mm3 per year.

As the figures are small the proposed development is not anticipated to have a large

potential peak flow reduction impact on the runoff of the immediate and general areas.

Mitigation Measures:

The discard dump rehabilitation process will be progressively be done. Clean water run-off

must be diverted around areas of disturbance. Where practicable, sediments must be

captured and retained on-site. This will reduce ranking from medium to low.


12-094 Page 35

Table 10-4: Magdalena Operational Phase Risk Assessment

M D S P

TOTAL

STATUS

SP M D S P

TOTAL

STATUS

SP

SURFACE WATER

Deterioration of surface water

quality

Discard Dump

Extpansion

Discard dump -

contaminated runoff10 4 3 4 68 - H

Consider runoff from discard dump as dirty

water. Maintain all water control

infrastructure. Design pollution control

structures to contain the 1:50 year flood

event

6 4 3 4 52 - M

Siltation of water resources All mine areas

All operation activities -

exposure of soil surfaces

and ineffective

rehabilitation

8 4 3 4 60 - MMaintain storm water infrastructure,

ensure effective rehabilitation6 4 3 4 52 - M

Pollution of water

resourcesExtension Dump

Discard Deposition - risk

of failure10 4 3 4 68 - H

Ensure regular inspection and maintenance

of the extension dump 6 4 3 3 39 - M

OPERATIONAL PHASE ACTIVITIES: DISCARD DUMP

MAGDALENA MINING AREA: 1. EXISTING AND DISCARD DUMP EXTENSION


AFTER MITIGATIONPOTENTIAL ENVIRONMENTAL

IMPACT

APPLICABLE

MAGDALENA MINE AREAACTIVITY


BEFORE MITIGATION

RECOMMENDED MITIGATION MEASURES


12-094 Page 36

Table 10-5: Magdalena Closure Phase Risk Assessment

M D S P

TOTAL

STATUS

SP M D S P

TOTAL

STATUS

SP

Pollution of water resources All mining areas

Removal of

infrastructure -

improper waste handling

and fuel/oil spills

8 4 3 4 60 - M

Manage waste effectively to

prevent pollution of water

resources

4 5 2 1 11 - L

Runoff and drainage from discard

dump continue to yield polluted

water

Existing discard and

Extended discard dumpRehabilitation 8 5 3 4 64 - H

Maintain dirty water

separation systems until the

site is rehabilitated and free

draining

6 5 1 2 24 - L

Siltation of water courses All mining areas

Removal of

infrastructure -

including water and

Magdalena pipelines

8 4 3 4 60 - M

Rehabilitate as soon as

possible, maintain erosion

control for the duration of

rehabilitation

4 2 2 3 24 - L

SURFACE WATER

POTENTIAL ENVIRONMENTAL

IMPACT

APPLICABLE TRP MINE

AREAACTIVITY


BEFORE MITIGATIONRECOMMENDED MITIGATION

MEASURES


AFTER MITIGATION

DECOMISSIONING and CLOSURE ACTIVITIES: REMOVAL OF INFRASTRUCTURE AND RUBBLE, REHABILITATION OF

DISTURBED AREAS

MAGDALENA MINING AREA: 1.EXISTING AND EXPANSION DISCARD DUMP


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11 MONITORING PROGRAM

The objectives of monitoring, as outlined in the mine EMP, is summarised in the table

below:

Table 11-1: Monitoring Objectives According to EMP

Surface Water Reporting

• During the operational phase,

monitoring is to conducted on the

monthly for surface monitoring

points, on three monthly during

closure.

• Ensure that not only the surface

water remaining on the site, but also

the surface water leaving the site of

the acceptable quality (during

operation and decommissioning

phase)

• Regular (monthly) inspections of the

relevant or possible causes of the

comprise or failure will be made.

Zinoju Mining has put measures in place to comply with these requirements. A short

summary of the current surface water on site can be viewed in a detailed report in Section

7.

Monitoring measures on the mine are characterised by monthly surface- and groundwater

quality monitoring at specific locations that can be seen in Appendix A. These monthly

quality monitoring measures are in line with the stipulations set out in the EMP.


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12 GAP ANALYSIS

From evaluation of all the different sections in this report the following gaps were

identified:

• From the hydrology of the catchment that the mine is situated in:

o The data used in the modelling from WR2005 is only up to 2005, this is not

updated. Modelling should be with up to date information and more models

should be considered.

o Some generic values are used which apply to bigger and whole catchment which

might not apply here as we are at the watershed.

• From the hydrology of the mine:

o Bloubankspruit water quality monitoring on the mine.

o A mine water balance; and

o A update of Mine SWMP


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13 CONCLUSION

The following conclusions are drawn from the Magdalena Hydrological study:

• From the hydrology of the catchment that the proposed Discard Dump mine is

situated in:

o The location of the mine is characterised by Water Management Area 7

UThukela (WMA 7) and quaternary catchment area V32D;

o The climate of the project area is characterised by a MAP of 792.1 mm and

MAE of 1 500 mm. Point rainfall of potential 1:50 year storms are defined

by 131.5 mm;

o The hydrology of the project area is characterised by a quaternary

catchment surface area size of 590 km2 (V32D). Furthermore the

quaternary hydrology is characterised by a MAR of 28.21 Mm3 and proposed

Discard Dump by a MAR of 0.47Mm3

o The peak flows for the proposed Discard Dump area are 0.36 m3/s and 0.46

m3/s for potential 1: 50 and 1:100 year storms

• From the hydrology of the mine:

o The surface water quality of the mine is characterized by 16 samples. From

the sample results and analyses it is seen that 10 of the 16 locations of the

water monitored on the mine site are within the SANS214:1 domestic water

use standard limits. However no acidic pH conditions were evident from any

of the other 6 surface water samples;

o The SWMP of the mine is characterised by two dirty catchments:

- the discard dump and slurry dam area;

- the coal processing area, including the administration buildings and

the workshops;

o Monitoring measures on the mine is characterised by monthly surface and

ground water quality monitoring at specific locations. These monthly

quality monitoring measures are in line with the stipulations set out in the

EMP.


12-094 Page 41

The following recommendations are made for the Magdalena hydrology:

• For the hydrology of the mine:

o A GN704 audit;

o A site visit and detailed investigation into the surface water of the mine to

update WB; and


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14 REFERENCES

Department of Water Affairs and Forestry (2008). Best Practice Guideline G3: Water

Monitoring System.

GCS (2002). Magdalena Environmental Management Program Report Ammendment, Phase 2.

GCS (2012). Magdalena 4th Quarterly Water Monitoring Report.

Kunz, R (2004). Daily Rainfall Data Extraction Utility, Version 1.4.

Middleton, B.J. and A.K. Bailey. (2009). Water Resources of South Africa, 2005 Study.

(WR2005). WRC Report No’s 380/08, 381/08, 382/08. Water Research Commission.

Pretoria.

Midgley, D.C., Pitman W.V. and Middleton, B.J. (1994). Surface Water Resources of South

SANRAL (2006). The South African National Road Agency Limited. Drainage Mannual, 5th

Edition, fully Revised

Smithers JC and Schulze RE. (2003) Design rainfall and flood estimation in SA

(Regionalisation of rainfall statistics for design flood estimation), Water Research

Commission Report No1060/1.


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APPENDIX A: MAGDALENA 2ND QUARTEYLY WATER MONITORING REPORT


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APPENDIX B: MAGDALENA STORM WATER MANAGEMENT PLAN REPORT


12-094 Page 45

surface water assessment for the magdalena colliery discard … · 2015. 9. 29. · 4a old main...

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