INYANDA MINING (PTY) LTD –
INYANDA COAL MINE
WATER AND SALT BALANCE UPDATE - 2020
REPORT REF: 20-1112-01_INYANDA WASHPLANT_2020_WB-
SB_UPDATEVERCC
(ANNUAL WATER AND SALT BALANCE UPDATE FOR THE INYANDA MINING
(PTY) LTD INYANDA COAL MINE)
VERSION CC
2021/02/19
REPORT REF: 20-1112-01_Inyanda Washplant_2020_WB-SB
Updated- 25/2/2021
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Document and Quality Control:
Document No: 20-1112-01_Inyanda Washplant_2020_WB-SB
AA - draft 2020/02/19 Chris Ingram Technical Review
BB – draft 2020/02/19 Leoni le Roux Quality review
Approved for Distribution:
0.0 Final report
Quality Control By:
Nature of Signoff Responsible Person Role / Responsibility Qualifications
Author Chris Ingram Civil Engineer (Pr.Eng) B.Eng. (Civil Engineering)
B.Eng. (Hons) (Water Resource Engineering)
Quality Reviewer Leoni le Roux Project Administration Professional Secretary and Personal Assistant
Reviewer Chris Fourie Civil Engineer (Pr.Eng) B.Eng. (Civil Engineering)
Client Pamela Senior Environmental
Officer
Disclaimer:
This is a legally binding document and many of the actions and recommendations remain the responsibility of the client (as the owner/lessee of the property).
Eco Elementum (Pty) Ltd and the authors of this report are protected from any legal action, possible loss, damage or liability resulting from the content of this report. This document is considered confidential and remains so unless requested by a court of law. Please consider the environment and only print this document if necessary.
The findings, results, observations, conclusions and recommendations given in this report are based on the author’s best scientific and professional knowledge, as well as available information. Information utilised and contained in this report is based on data/information supplied to Eco Elementum (Pty) Ltd by the client and other external sources (including previous site investigation data and external specialist studies).
Eco Elementum (Pty) Ltd exercises due care and diligence in rendering services and preparing documents, however it has been assumed that the information provided to Eco Elementum (Pty) Ltd is correct and as such the accuracy of the conclusions made are reliant on the accuracy and completeness of the data supplied.
No responsibility is accepted by Eco Elementum (Pty) Ltd for incomplete or inaccurate data supplied by the client and/or other external sources. Opinions expressed in this report apply to the site conditions and features that existed at the time of the start of the investigations and the production of this document. For this reason. Eco Elementum (Pty) Ltd accepts no liability, and the client by receiving and therefore accepting this document, indemnifies Eco Elementum (Pty) Ltd and its directors against all actions, claims, demands, losses, liabilities, costs, damages and expenses arising from or in connection with the services rendered, directly or indirectly.
The document may not be altered or added to without the prior written consent of the author. This also refers to electronic copies of the report that are supplied for the purposes of inclusion as part of other reports.
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CONTENTS
KEY PROJECT INFORMATION ............................................................................................................................................................. 5
1. INTRODUCTION ............................................................................................................................................................... 6
1.1 ACTIVITY BACKGROUND ........................................................................................................................................................ 6
1.2 LOCALITY ............................................................................................................................................................................. 6
2. DESCRIPTION OF THE CURRENT ENVIRONMENT ...................................................................................................... 8
2.1 WATER MANAGEMENT AREA ................................................................................................................................................. 8
2.1.1 Quaternary Catchment B20G ............................................................................................................................................ 8
2.1.2 Topography and Drainage of Site ...................................................................................................................................... 8
2.2 REGIONAL GEOLOGY ............................................................................................................................................................ 8
3. CLIMATIC CONDITIONS .................................................................................................................................................. 9
3.1 RAINFALL AND EVAPORATION ................................................................................................................................................ 9
3.1.1 Storm Rainfall Depths ........................................................................................................................................................ 9
4. WATER BALANCE ......................................................................................................................................................... 11
4.1 SURFACE WATER MANAGEMENT ......................................................................................................................................... 11
4.2 BENEFICIATION PLANT ........................................................................................................................................................ 11
4.3 CO DISPOSAL FACILITY ...................................................................................................................................................... 12
4.4 FLOW MEASUREMENTS ...................................................................................................................................................... 12
4.4.1 Installed ........................................................................................................................................................................... 12
4.4.2 Additional ......................................................................................................................................................................... 12
4.5 LONG TERM SIMULATION .................................................................................................................................................... 12
4.5.1 Runoff .............................................................................................................................................................................. 12
4.5.2 OPERATIONS PHILOSOPHY ................................................................................................................................................. 14
4.5.3 DOMESTIC ......................................................................................................................................................................... 14
4.5.4 VOLUMES .......................................................................................................................................................................... 14
4.5.5 WATER BALANCE SUMMARY ............................................................................................................................................... 17
5. SALT BALANCE ............................................................................................................................................................. 18
5.1 METHODOLOGY .................................................................................................................................................................. 18
5.2 LOADINGS .......................................................................................................................................................................... 19
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List of Figures
Figure 1: Inyanda Coal Mine Locality ..................................................................................................................................................... 7
Figure 2: Inyanda Coal Mine General Surface Plan ............................................................................................................................... 7
Figure 3: Inyanda Coal Mine Water Balance Flow Diagram ................................................................................................................. 13
Figure 4: Inyanda Coal Mine Average Daily Water Usage ................................................................................................................... 15
Figure 5: Graphical representation of long terms RWD simulation....................................................................................................... 17
Figure 6: Inyanda Average Daily Salt Loadings.................................................................................................................................... 20
List of Tables
Table 1: Project Information ................................................................................................................................................................... 5
Table 2: Summary of Rainfall and S-Pan evaporation data.................................................................................................................... 9
Table 3: Adopted design rainfall ........................................................................................................................................................... 10
Table 4: Wash plant operational data ................................................................................................................................................... 11
Table 5: Long term Runoff .................................................................................................................................................................... 12
Table 6: Summary of Water Balance Operational Philosophy.............................................................................................................. 14
Table 7: Average Annual Water Usage (m3/annum) ............................................................................................................................ 16
Table 8: Salt balance water quality data ............................................................................................................................................... 18
Table 9: Average Annual Salt Loadings (tonne/annum) ....................................................................................................................... 21
Abbreviations
AASHTO: America Association of State Highway and Transportation ASTM American Society for Testing and Materials CCL: Compacted Clay Layer CQA Quality Auditor Certification CQC Care Quality Commission CQP: Construction Quality Plan GM: Geomembrane GRI Geosynthetic Research Institute HDPE: High Density Poly Ethylene MAP: Mean Annual Precipitation MAMSL Metres above Means Sea Level MQA Mining Qualifications Authority MQC Mining Qualifications Authority NWA: National Water Act PCD: Pollution Control Dam PWD: Process Water Dam ROM: Run of Mine. RWD: Return Water Dam SANS South African National Standards SANS South African National Standards SB Salt Balance WB Water Balance WMA: Water Management Area
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KEY PROJECT INFORMATION
Table 1: Project Information
Project: Inyanda Mine WB/SB Update
Trading name (if any): Inyanda Mining Holdings (Pty) Ltd: Inyanda Coal Mine
Contact person: Mrs Ninette Barnard
Email: [email protected]
Telephone: 060 980 8903
Pr_Eng Chris Ingram (Professional Engineer)
Contact person: Chris Ingram for Eco Elementum Engineering (Pty) Ltd
Postal address: 361 Oberon Ave, Glenfield Office Park, Nikka Building, 1st Floor, Faerie Glen, Pretoria,
0081.
Postal code: 0184
Telephone: 012 807 0383
E-mail: [email protected] / [email protected]
Qualifications &
relevant experience 12 Years’ experience in Water Resource and Water Utilization Engineering
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Eco Elementum (Pty) Ltd | Office number: 012 807 0383 | Website: www.ecoe.co.za | Email: [email protected]
1. INTRODUCTION
1.1 ACTIVITY BACKGROUND
Inyanda Mining Holdings purchased Inyanda Coal Mine from Exxaro Coal (Pty) Ltd on 23 November 2015. Notification
of the sale was given to the Department of Water and Sanitation on 12 May 2016. Inyanda Mining Holdings requested
that the water use license be transferred from Exxaro Coal (Pty) Ltd to Inyanda Mining Holdings on 13 January 2017.
Coal is delivered by truck to Inyanda Coal Mine. Inyanda Coal Mine is an opencast coal mine that has ceased its mining
operation and is currently only operating a washing plant. The opencast pit has been fully rehabilitated and vegetated.
Inyanda Coal Mine operates a filter press.
Inyanda Coal Mine operates a co-disposal facility (discards and slurry). Disposal is taking place at the co-disposal
facility as an interim measure, slurry will also be disposed into the co-disposal facility while the RWD is dredged. The co-
disposal area will be rehabilitated in future. There are three workshop areas, each with its own wash bay, waste
management area and oil separators.
1.2 LOCALITY
The Inyanda Coal Mine is situated approximately 11 km North of Emalahleni in the Mpumalanga Province. The mine is
also located adjacent to the R554 provincial road between the towns of Emalahleni and Verena. The regional location of
the mine is shown in Figure 1
The current mine layout and surface plan is shown on Figure 2
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Figure 1: Inyanda Coal Mine Locality
Figure 2: Inyanda Coal Mine General Surface Plan
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2. DESCRIPTION OF THE CURRENT ENVIRONMENT
2.1 WATER MANAGEMENT AREA
2.1.1 Quaternary Catchment B20G
The Inyanda Coal Mine falls within the Olifants Water Management area and the Wilge River catchment area, which is
demarcated as a tertiary drainage region B11, and more specifically within the quaternary catchment B11K and B11J
(Blesbokspruit).
The Blesbokspruit is located approximately 4 km west of the mine and the Olifants 7 km east. The Blesbokspruit flows in
a northerly direction for approximately 4 km before discharging into the Klip River. The Klip River flows approximately 15
km to the north east where it flows into the Olifants River, approximately 33 km north of Emalahleni town. The Olifants
River merge with the Limpopo River that drains into the Indian Ocean at Xai-Xai, Mozambique.
2.1.2 Topography and Drainage of Site
The area on the site, where coal beneficiation currently occurs, drains in a north westerly direction toward the Klip River,
with the high point being the south east corner having an approximate level of 1,537 mamsl and the lowest point the
north western corner with an approximate level of 1,513 mamsl.
2.2 REGIONAL GEOLOGY
According to the 1:250 000 geological map 2628 East Rand, the site is underlain by sandstone, shale and coal beds of
the Vryheid Formation, Ecca Group, Karoo Supergroup. In addition, quartzite and shale from the Daspoort Formation of
the Pretoria Group are expected to occur in isolated sections throughout the site.
The Vryheid Formation consists of coal seams, grits, sandstone, arkoses and mud rock all deposited under shallow-
water conditions. A significant feature of the formation is the close intercalation of these different soil and rock types
within it. For example, it is not uncommon to find a lens of weak mudstone between competent layers of sandstone or a
coarse layer of sandstone between layers of soft silt. The relatively weaker soil horizons in the profile are however
unlikely to affect the foundation design of conventional buildings or even structures several storeys in height. (Brink,
1983).
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3. CLIMATIC CONDITIONS
3.1 RAINFALL AND EVAPORATION
The Study Area falls within the summer rainfall region of South Africa, which is warm temperate, with cold dry winters
and warm summers. The summer rainfall is sporadic, with frequent thunderstorms, associated with high intensity rainfall
events.
The Witbank Weather Station at the Witbank Dam is the closest station, with reliable results since 1967. The Mean
Annual Precipitation (MAP) is reported as 702.7 mm per annum.
Relatively high levels of evaporation occur in the area. The maximum evaporation rate occurs in January, with a mean
rate of 5.3 mm per day. Evaporation is greater than rainfall for all months of the year resulting in a marked moisture
deficit in the region.
The average rainfall and average evaporation figures are shown in Table 2.
Table 2: Summary of Rainfall and S-Pan evaporation data
3.1.1 Storm Rainfall Depths
The design rainfall for the project area was determined using the Design rainfall estimation in South Africa program.
The design rainfall for the various return periods for the coordinates 26°07’S, 28°50’E is shown in Table 3.
Month Mean Annual Precipitation (mm) Evaporation (mm)
January 131.5 164.5
February 91.8 138.4
March 73.8 129.8
April 39.3 97.4
May 13.4 79.8
June 7.0 65.3
July 2.9 72.5
August 7.9 98.8
September 20.7 137.3
October 78.3 163.7
November 123.8 158.5
December 116.7 163.6
Mean Annual Total 702.7 1476.2
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Table 3: Adopted design rainfall
Duration Return Period Rainfall (mm)
1:2 1:5 1:10 1:20 1:50 1:100
1 day 52.5 72.5 87.6 103.7 127.1 146.8
2 day 64.6 89.2 107.8 127.6 156.5 180.7
3 day 72.9 100.7 121.8 144.1 176.7 204.1
7 day 93.3 128.8 155.7 184.3 226 261
24 hour 60.6 83.6 101.1 119.7 146.8 169.5
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4. WATER BALANCE
The beneficiation plant has well developed surface water management infrastructure and complies with the requirements
as contained in the NWA, Regulation no 7 of 1999 (GN 704).
The surface water management infrastructure is in urgent need of maintenance. The Return Water Dam (RWD) has
entirely silted up with almost zero (0%) capacity. The co-disposal return channels and storm water drainage
infrastructure also needs to be upgraded/refurbished.
The water balance update was prepared based on the current activities and existing water consumption figures provided
by the mine. A schematic flow diagram of the water balance is shown on Figure 4
4.1 SURFACE WATER MANAGEMENT
The dirty water runoff from the beneficiation plant area is conveyed to the RWD by means of lined concrete channels.
The return water and storm water runoff from the CDF is also conveyed to the RWD by means of unlined channels.
Dust suppression is primarily implemented on the coal stockpiles, platforms and on the internal roads. Typically, the
application rate for dust suppression is limited to 1.0 l.m2/day.
4.2 BENEFICIATION PLANT
The wash water is provided from the process water dam (PWD) located adjacent to the plant. The underflow from the
thickener is mechanically dewatered by means of a filter press and the supernatant returned to the PWD. The water
deficit is currently augmented from the Danie Keet dam.
The wash plant operations data that was used in the water balance update was obtained from the Inyanda production
rate report and is summarized in Table 4.
Table 4: Wash plant operational data
ROM feed (t/hr) 252.7
Yields (%) Product 65%
Discard 8%
Slurry 27%
Moisture Content (% m/m) ROM 4%
Product 10%
Discard 12%
Solids Content (% m/m) Thickener Feed 8%
Thickener Underflow 32%
Filter Cake 65%
Flow Rates (m3/hr) Slurry (m3/hr) 76.1
Underflow (m3/hr) 56
Wash water (m3/hr) 253
Wash water(m3/t) 1.00
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4.3 CO DISPOSAL FACILITY
The CDF is only utilised when the filter press is non-operational, due to maintenance or breakdown. It is assumed that
the press has a ninety percent (90%) availability.
4.4 FLOW MEASUREMENTS
4.4.1 Installed
The site has only been equipped with three (3) flow meters. The meters are as follows:
I. Inyanda borehole delivery. The mechanical flow meter has been installed on the delivery line.
II. Dust suppression goose neck. A mechanical flow meter has been installed upstream of the Gooseneck.
III. Danie Keet dam. The mechanical flow meter has been installed on the delivery line from the farm dam to the
raw/process water dam (PWD).
4.4.2 Additional
In order to accurately update the water balance, as well as the water conservation and demand strategy, it is proposed
that the following additional flow meters be installed.
IV. RWD inlet (silt trap) and Outlet (Spillway). Flow needs to be measured at the inlet and outlet of the PCD. This
will also assist in identifying any leakage from the barrier system.
V. Delivery line from the RWD to the PWD.
VI. Inlet to the beneficiation plant.
VII. Wastewater treatment works. The flow to the biofilter plant needs to be measured.
4.5 LONG TERM SIMULATION
4.5.1 Runoff
In order to accurately simulate the reliable, long term, surface water yield, an extended rainfall record is required. The
rainfall station with the most reliable long-term record is the Groenfontein Station located at Bronkhorstspruit Dam, with
records extending over a period of more than fifty (50) years (1967 to 2019). In total 3 665 rainfall events were recorded
through this period.
Table 5: Long term Runoff
Total Record (years) 51.08
Average MAE (mm) 1496.78
Average MAP (mm) 689.78
Average Rain Days (d/year) 71.75
Average MAR as MAP (%)
Plant Area 11.1 %
CDF 20.7 %
Stockpiles 6.7 %
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Figure 3: Inyanda Coal Mine Water Balance Flow Diagram
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4.5.2 OPERATIONS PHILOSOPHY
A summary of the proposed operation volumes and methodology is provided in the Table 6.
Table 6: Summary of Water Balance Operational Philosophy
Volumes
Potable Water - Boreholes Nominal (m3/d) 6.7
Dust Suppression Nominal (m3/d) 75
Max (m3/d) 225
Wash plant Usage (m3/d) 6 073
Recovery 85 %
PCD Operation
RWD (80 % Silt) Volume (m3) 45 000
Normal Operating Level 75%
Dust Suppression Min Pumping Level 0.50%
Double Pumping 75.00%
4.5.3 DOMESTIC
The current water demand was obtained from the existing flow metre record attained from the mine. The total average
daily consumption is approximately 27.9 m3/d.
Using an average consumption of 80 l/c/d for temporary staff (i.e. day workers) it equates to a total of approximately 348
workers per day, or 116 per shift.
The wastewater generated from the domestic usage is conveyed to a rotating biological plant for treatment. The final
effluent is stored in a lined biofilter dam.
4.5.4 VOLUMES
The average daily water balance for the mine is shown on Figure 2 and the annual water balance volumes is provided in
Table 7.
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Figure 4: Inyanda Coal Mine Average Daily Water Usage
242.6 396.8
6061.5 5330.8
195.5
381.0
TOTAL 6304.1 0.000 6304.1 TOTAL
5330.8 3930.0
0.5 140.1
1260.8
0.5
TOTAL 5331.3 5331.3 TOTAL
5.6 6061.5
966.4 10.7
3930.0 90.1
1034.5
225.9
TOTAL 6162.3 6162.3 TOTAL
Rainfall 69.9 64.0
Slurry Water 140.1 63.0
8.9
6.2
67.8
TOTAL 210.0 210.0 TOTAL
1265.7 102.3
52.2
225.2
886.0
TOTAL 1265.7 1265.7 TOTAL
Rainfall Dam 105.7 225.9
Stockpile Runoff 52.2 9.9
Washplant Runoff 102.3 12.5
CDF 63.4 74.3
TOTAL 323.6 322.5 TOTAL
Borehole 27.9 8.0
11.5
348.2
8.4
TOTAL 27.9 27.9 TOTAL
8.0 15.9
7.9
TOTAL 15.9 15.9 TOTAL
Wet Beach Evap
Dry Beach Evap
Evaporation
Entrained/Losses
Evap
DIRTY AREAS
Rainfall Washplant Runoff
RBC
Consumptive Usage
Offices
Return Water Dam (RWD)
Spillage
Raw Water Dam (PWD)
Seepage
RBC Effluent Evaporation
Rainfall
Losses
Biofilter Dam (BD)
Stockpile Runoff
Dust Supression
CDF
Thickner Return
Filter Press
CO-DISPOSAL FACILITY (CDF)
Raw Water Dam (PWD)
Pool Evap
Entrained/Losses
Rainfall
Evaporation
Return Water Dam (RWD)
Filter Press Return
Keet Dam
(Ext Source)
Return Water Dam (RWD)
OUT (m3/d)IN (m3/d)
WASHPLANT
Product
Direct Rainfall
Slurry
THICKENER
Evaporation
Washplant
Losses
PWDSlurry
ROM
PWD
Discard
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Table 7: Average Annual Water Usage (m3/annum)
AREA IN (m3/annum) TOTAL
Wash Plant ROM PWD
88 598 2 213 970 2 302 569
Thickener Slurry Rainfall
1 947 078 183 1 947 261
Process Water Dam (PWD)
Rainfall Keet Dam (Ext Source)
Thickener Return Filter Press Return
Return Water Dam (RWD)
352 985 2 029 1 435 424 377 837 82 507 2 250 781
Co-Disposal Facility (CDF)
Rainfall Slurry Water
25 543 51 165 76 708
Dirty Areas Rainfall
462 313 462 313
Return Water Dam (RWD)
Rainfall Dam Stockpile Runoff Wash plant Runoff
CDF
38 598 19 068 37 376 23 153 118 195
Offices Borehole
10 175 10 175
Biofilter Dam (BD)
RBC Effluent Rainfall
2 922 2 899 5 821
TOTAL 7 173 822
OUT (m3/annum)
Wash Plant Product Slurry Discard Losses
144 924 1 947 078 71 420 139 147 2 302 569
Thickener PWD CDF Filter Press Evaporation
1 435 424 51 165 460 489 183 1 947 261
Process Water Dam (PWD)
Wash plant Evaporation Dust Suppression
2 213 970 3 909 32 902 2 250 781
Co-Disposal Facility (CDF)
Return Water Dam (RWD)
Entrained/Losses Pool Evaporation Wet Beach Evaporation
Dry Beach Evaporation
23 380 23 012 3 260 2 282 24 774 76 708
Dirty Areas Stockpile Runoff
Wash plant Runoff
Entrained/Losses Evaporation
19 068 37 376 82 249 323 619 462 313
Return Water Dam (RWD)
Raw Water Dam (PWD)
Seepage Spillage Evaporation
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82 507 3 601 4 554 27 133 117 795
Offices RBC
Consumptive Usage
Losses
2 922 4 201 3 053 10 175
Biological Dam (BD)
Evaporation
5 821 5 821
TOTAL 7 173 422
BALANCE (%) 0.006%
4.5.5 WATER BALANCE SUMMARY
The static water balance was simulated over a period of approximately fifty years. The RWD has substantial silt build up
(80%) significantly reducing its capacity. The dirty water collected in the RWD is periodically pumped to the PWD.
The following is a summary of the simulation results.
• Approximately 67 525 m3/annum is pumped to the RWD. It is assumed that the pumping rate is limited to 500 m3/d.
• The RWD spills numerous (127) times during the fifty year simulation period.
• In order to comply with GN 704 requirements, the RWD needs a minimum capacity of 63 500 m3.
A graphical representation of the results is shown on Figure 5.
Figure 5: Graphical representation of long terms RWD simulation
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5. SALT BALANCE
Coal mining, and its associated activities, may often lead to degradation in water resource quality. Although the
pollutants may often vary the total dissolved salt (TDS) provides a good indication of the extent of water contamination.
The TDS is representative of the total inorganic salt content dissolved in water. High TDS impart a salty or bitter taste to
water. Salts such as sulphates are not easily removable from drinking water and advances processes such as ion
exchange or membrane processes need to be incorporated in conventional drinking water plants, to remove sulphates.
5.1 METHODOLOGY
The primary source of TDS for Inyanda is the coal that is transported to site. Due to its high solubility, these salts are
readily dissolved in ground or surface water that may come into contact with the exposed coal material.
The coal ROM is stockpiled on site before being fed to the beneficiation plant. Various grades of coal is also stockpile
on site. The dry waste material is mechanical stacked on the CDF.
The salt balance was developed on the hydraulic (flow) balance established with the water balance taking into account
all inflow, internal flows and outflows. The salt balance is determined based on the principal of conservation of mass,
assuming all salts are retained within the system and does not take into consideration any potential chemical, biological
or mechanical salt reduction.
The flow data from the water balance, together with the water quality data from the water-monitoring programme was
used to calculate the various salt loadings and balances. Where water quality data was not available, reasonable
assumptions were made based on similar projects. A Summary of the water quality data used in the salt balance is
shown in Table 8.
Table 8: Salt balance water quality data
Description TDS (mg/l) Data Source
Evaporation 5 Estimate
Rainfall 10 Estimate
Borehole 258 Monitoring Results
Product 2000 Estimate
ROM 2000 Estimate
Thickener overflow 1500 Estimate
Underflow 3403 Estimate
Slurry 2000 Estimate
Domestic Sewage 400 Estimate
CDF Runoff 3755 Estimate
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Runoff 3211 Estimate
Return Water 2970 Monitoring Results
Biological Sewage Dam 320 Monitoring Results
Danie Keet 45 Monitoring Results
Process Water Dam 1751 Monitoring Results
5.2 LOADINGS
The average daily salt loadings for Inyanda is shown on Figure 6 and of the annual loadings is provided in Table 9.
REPORT REF: 20-1112-01_Inyanda Washplant_2020_WB-SB
Updated- 25/2/2021
20 | P a g e
Eco Elementum (Pty) Ltd | Office number: 012 807 0383 | Website: www.ecoe.co.za | Email: [email protected]
Figure 6: Inyanda Average Daily Salt Loadings
kg/d kg/d
242.6 485 794 396.8
6061.5 10 612 10 662 5330.8
1 511 391 195.5
762 381.0
TOTAL 6304.1 12 608 12 608 6304.1 TOTAL
5330.8 10 662 5 895 3930.0
0.5 0 477 140.1
4 290 1260.8
0 0.5
TOTAL 5331.3 10 662 10 662 5331.3 TOTAL
5.6 0 10 612 6061.5
966.4 44 0 10.7
3930.0 5 895 158 90.1
1034.5 4 290 130
225.9 671
TOTAL 6162.3 10 900 10 900 6162.3 TOTAL
Rainfall 69.9 1 240 64.0
Slurry Water 140.1 477 237 63.0
0 8.9
0 6.2
0 67.8
TOTAL 210.0 477 0 477 210.0 TOTAL
1265.7 13 329 102.3
168 52.2
1 211
723 225.2
4 886.0
TOTAL 1265.7 1 224 1 224 1265.7 TOTAL
Rainfall Dam 105.7 1 671 225.9
Stockpile Runoff 52.2 168 29 9.9
Washplant Runoff 102.3 329 37 12.5
CDF 63.4 240 0 74.3
TOTAL 323.6 738 0 738 322.5 TOTAL
Borehole 27.9 6 3 8.0
2 2 11.5
2 8.4
TOTAL 27.9 7 7 27.9 TOTAL
8.0 3 0 15.9
7.9 0 3
TOTAL 15.9 3 3 15.9 TOTAL
WASHPLANT
IN (m3/d) OUT (m3/d)
ROM Product
PWD Slurry
Discard
Losses
THICKENER
Slurry PWD
Rainfall CDF
Filter Press
Evaporation
Raw Water Dam (PWD)
Direct Rainfall Washplant
Keet Dam
(Ext Source)Evaporation
Return Water Dam (RWD)
Entrained/Losses
Pool Evap
Evaporation
Wet Beach Evap
Dry Beach Evap
Thickner Return Dust Supression
Filter Press Return
Return Water Dam (RWD)
CO-DISPOSAL FACILITY (CDF)
Evap
Return Water Dam (RWD)
Raw Water Dam (PWD)
Seepage
Spillage
DIRTY AREAS
Rainfall Washplant Runoff
Stockpile Runoff
Entrained/Losses
Rainfall Carbanaceous Storage
Carbanaceous Material
Carbanaceous Material
Carbanaceous Storage
Carbanaceous Source
RBC
Consumptive Usage
Losses
Biofilter Dam (BD)
RBC Effluent Evaporation
Offices
REPORT REF: 20-1112-01_Inyanda Washplant_2020_WB-SB
Updated- 25/2/2021
21 | P a g e
Eco Elementum (Pty) Ltd | Office number: 012 807 0383 | Website: www.ecoe.co.za | Email: [email protected]
Table 9: Average Annual Salt Loadings (tonne/annum)
AREA IN (tonne/annum) TOTAL
Wash Plant ROM PWD
Carbonaceous Material
177 3 876 552 4 605
Thickener Slurry Rainfall
3 894 0 3 894
Process Water Dam (PWD)
Rainfall Keet Dam (Ext Source)
Thickener Return Filter Press Return
Return Water Dam (RWD)
0 16 2 153 1 567 245 3 981
Co-Disposal Facility (CDF)
Rainfall Slurry Water
0 174 174
Dirty Areas Rainfall
Carbonaceous Material
5 442 447
Return Water Dam (RWD)
Rainfall Dam Stockpile Runoff Wash plant Runoff
CDF
0 61 120 88 269
Offices Borehole
Carbonaceous Material
2 1 3
Biofilter Dam (BD)
RBC Effluent
Rainfall
3 0 3
TOTAL 13 377
OUT (tonne/annum)
Wash Plant Product Slurry Discard Losses
290 3 894 143 278 4 605
Thickener PWD CDF Filter Press Evaporation
2 153 174 1 567 0 3 894
Process Water Dam (PWD)
Wash plant Evaporation Dust Suppression Carbonaceous Storage
3 876 0 58 47 3 981
Co-Disposal Facility (CDF)
Return Water Dam (RWD)
Entrained/Losses Pool Evaporation Wet Beach Evaporation
Dry Beach Evaporation
88 86 0 0 0 174
REPORT REF: 20-1112-01_Inyanda Washplant_2020_WB-SB
Updated- 25/2/2021
22 | P a g e
Eco Elementum (Pty) Ltd | Office number: 012 807 0383 | Website: www.ecoe.co.za | Email: [email protected]
Dirty Areas
Stockpile Runoff
Wash plant Runoff
Entrained/Losses Evaporation
120 61 264 2 447
Return Water Dam (RWD)
Raw Water Dam (PWD)
Seepage Spillage Evaporation
245 11 14 0 269
Offices RBC
Consumptive Usage
Losses
1 1 1 3
Biofilter Dam (BD)
Evaporation Carbonaceous Storage
0 1 1
TOTAL 13 375
BALANCE (%) 0.013%