LONMIN EASTERN PLATINUM Ltd - OPERATIONS

SPECIALIST REPORT: SURFACE WATER

PART OF THE ENVIRONMENTAL ASSESSMENT AND AUTHORISATION PROCESS FOR THE PROPOSED CONSTRUCTION OF A NEW CHROME PLANT

PROJECT REFERENCE NR: 100279

REPORT REFERENCE DATE: 8 JANUARY 2018

REVISION 0.0

PREPARED BY:

E-TEK CONSULTING

LONMIN EASTERN PLATINUM – SURFACE WATER SPECIALIST REPORT

CLIENT DETAILS:

CLIENT Lonmin Eastern Platinum Limited

CONTACT PERSON Alta Van Dyk: Alta Van Dyk Environmental Consultants CC

Email: [email protected]

CONTACT DETAILS Tel +27(0)12 940 9089

Mobile: +27(0)82 782 4005

CONSULTANT DETAILS:

CONSULTANT E-TEK Consulting

CONTACT PERSONS Pieter Vlok, P Harris

Email: [email protected]

CONTACT DETAILS Tel: +27 (0) 18 294 3652

Mobile +27 (0) 83 446 6154 P O Box 19144 POSTAL ADDRESS Noordbrug 2522

PHYSICAL ADDRESS 7 Solomon Street, Potchefstroom, South-Africa

DOCUMENT CONTROL:

PROJECT TITLE Lonmin EPL expansion: Surface Water Specialist Report

REPORT STATUS Rev 0.0

REPORT NUMBER RPT 100279

CONTRACT -

SIGN-OFF NAME SIGNATURE DATE

AUTHOR P. Vlok Pr Tech (Eng) DOCUMENT P. Harris (BSc Eng) REVIEWER ACCEPTED BY

APPROVED BY

ELECTRONIC DISTRIBUTION HARD COPY COPY

E-TEK Consulting

Alta Van Dyk Environmental Consultants CC

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DECLARATIONS AND DISCLAIMER

INDEPENDENCE E-TEK Consulting (Pty) Ltd (E-TEK) hereby declares that it is an independent consulting company in that it has no business, financial, personal or other interest in this project in respect of which E-TEK is appointed. Furthermore, no circumstances exist that may compromise the objectivity of E-TEK, excluding fair remuneration for work performed in connection with this surface water management plan. COMPETENCE OF PROJECT TEAM

• PM Harris (B.Sc. Eng (Agric) has been practicing in the field of environmental management and engineering for the past 17 years. The focus area in his career has been the compilation and implementation of closure, rehabilitation and stormwater management plans.

• P Vlok (B. Tech Engineering Civil), (B.Sc. (Water Resources)), (Pr. Tech Eng) has been practicing in the field of construction management and engineering for the past 11 years. His focus area is the design and implementation of stormwater management plans.

DISCLAIMER This report has been produced by E-TEK Consulting (Pty) Ltd., (hereafter “E-TEK”) with the skill and care ordinarily exercised by a reasonable Environmental Consultant at the time the services were performed. Further, and in particular, the Services were performed by E-TEK taking into account the limits of the scope of works required by the Client, the time scale involved and the resources, including financial and manpower resources. Any and all intellectual property rights in this report remain the property of E-TEK. This report is produced exclusively for the purposes of the Client and is confidential to the Client and their assigns. E-TEK accepts no responsibility of whatsoever nature to third parties to whom this report, or any part thereof, is made known. Any third party relies upon the report at their own risk. E-TEK shall not be liable for any loss or damage caused by or arising out of circumstances over which E-TEK have no control, such as the use and interpretation of this report by the Client, its officials, their representatives or agents. Furthermore, E-TEK hereby disclaims any responsibility to the Client and others in respect of any matters outside the scope of work as agreed in the relevant proposal. None of the work performed during this project shall constitute or be represented as a legal opinion of any kind or nature, but shall be a representation of the findings. No warranties or guarantees, expressed or implied, are included in or intended by the report, except that it has been prepared in accordance with the current generally accepted practices and standards consistent with the level of care and skill exercised under similar circumstances by professional consultants or firms that perform the same or similar services. Any reference to legislation in this report should not be perceived as a substitute for the provisions of such legislation. In the event of any inconsistency between this document and such legislation, the latter would prevail. Whilst every endeavour has been made by the E-TEK to ensure that information provided is correct and relevant, this report is, of necessity, based on information that could reasonably have been sourced within the time period allocated to the assessment, and is, furthermore, of necessity, dependent on information provided by management and/or its representatives. It should, accordingly, not be assumed that all possible and applicable findings, observations and/or measures are included in this report as this report represents a sample of assessable parameters. As a subsequent event, should additional information become available, E-TEK reserves the right to amend its findings, observations, measures and executive summary.

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EXECUTIVE SUMMARY

Lonmin Eastern Platinum Ltd (Marikana Operations) (Lonmin Marikana) has initiated an expansion project of the existing chrome plant.

As part of the required Environmental Impact Assessment (EIA) process, a specialist study is required relating to the hydrology of the site and stormwater management infrastructure requirements. This includes the following:

• Hydrology of upstream catchments and infrastructure;

• A stormwater management plan (SWMP) for the proposed project which complies to all applicable legislation;

• Conceptual designs of the infrastructure required for the functioning of the SWMP;

• The delineation of the 1:100 yr floodlines of drainage lines impacting on the site;

• The delineation of the 100m exclusion zone of drainage lines impacting on the site;

• Impact assessments for: Construction-, operational- and closure phases.

The following regulations described in Government Notice No. 704 Operational Guideline No. M6.1 are relevant to this site and cited in the report.

• Regulation 4: Restrictions on locality;

• Regulation 6: Capacity requirements of clean and dirty water systems;

• Regulation 7. Protection of water resources.

The Department of Water and Sanitation’s Resource Protection and Waste Management hierarchy of decision-taking is based on a precautionary principle and sets the order of priority for water and waste management decisions and/or actions. This project aims to manage surface water up to the first two levels of the hierarchy namely

• Prevent or minimise pollution / contamination of water by implementing necessary management measures or strategies;

• Reuse or Reclaim contaminated water in cases where complete pollution prevention was not possible.

Also included in this document is a brief description of the methodology used to calculate the positions of the floodlines and all flood calculations required for the sizing of infrastructure which is identified as a minimum requirement for compliance to legislation and best practice.

The optimal functioning of the stormwater management plan for the proposed chrome plant expansion is described in this document in the section dealing with the Legislative compliance aspects. Refer to the summaries in Table 1, Table 2 and Table 3 below:

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Table 1: Compliance to GN 704 regulation 4

DESCRIPTION ADHERENCE Restrictions on locality Outside the 1in100-year Floodline; Outside the 100 m Exclusion zone.

Table 2: Compliance to Regulation 6: Summary of proposed infrastructure requirements

PROPOSED FACILITIES CAPACITY REQUIREMENTS OF CLEAN AND DIRTY WATER SYSTEMS AND SPECIFICATIONS Silt trap Capacity per compartment: 500 m3; Silt management is required to ensure that the Barrier requirements: Waste “Type 3” requiring a capacity of the pollution control dam (PCD) is not “Class C” liner with leakage detection; compromised over time. Required licenced storage capacity: A dual silt trap is proposed to facilitate regular Total: 500 m3. maintenance although not indicated in this document. Pollution control dam (PCD) Barrier requirements: Waste “Type 3” requiring a “Class C” liner with leakage detection; Sub surface drains – confirm water table depth; 1000mm free board above spillway; Max dam depth: 3.0m (below NOC); Licenced capacity: 7700 m3 (FSL). Bundwalls Entire plant bunded to contain all dirty water and shed clean water to the environment.

Table 3: Compliance to Regulation 7: Protection of water resources

PROPOSED FACILITIES CAPACITY REQUIREMENTS OF CLEAN AND DIRTY WATER SYSTEMS AND SPECIFICATIONS Bunding and paving All dirty water contained in a PCD sized to handle a 1:50 yr storm event plus operational water needs; Pumping capacity to empty PCD to NOL within 24 hours; Reinforced concrete paving over entire plant footprint. Management protocol Management of the site during construction, operations and decommissioning.

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TABLE OF CONTENTS

1. TERMS OF REFERENCE ...... 11 2. LEGISLATIVE REQUIREMENTS ...... 11 2.1. EXTRACTS FROM GN704 APPLICABLE TO THIS PROJECT ...... 11 2.1.1. Regulation 4: Restrictions on locality ...... 11 2.1.2. Regulation 6: Capacity requirements of clean and dirty water systems...... 12 2.1.3. Regulation 7. Protection of water resources...... 12

3. PRINCIPLES OF STORM WATER MANAGEMENT AND HIERARCHY OF DECISION TAKING ...... 12 3.1. PRINCIPLES OF STORM WATER MANAGEMENT ...... 12 3.2. HIERARCHY OF DECISION-TAKING WITH RESPECT TO STORM WATER MANAGEMENT .... 14

4. LOCALITY OF THE SITE ...... 14 5. SITE VISIT ...... 16 6. BACKGROUND INFORMATION AFFECTING THE PROJECT...... 16 6.1. TOPOGRAPHY, CLIMATE, VEGETATION AND GEOLOGY, ...... 16 6.2. INFRASTRUCTURE WITHIN CATCHMENTS UPSTREAM OF THE PROJECT SITE ...... 16 6.3. GN704 STORMWATER MANAGEMENT PLAN FOR EASTERN PLATINUM LIMITED ...... 17 6.3.1. Saffy Shaft ...... 17 6.3.2. EPL Plant ...... 18 6.3.3. EPC Plant ...... 19 6.4. GEOTECHNICAL INVESTIGATION FOR PROPOSED NEW EPC GN704 STORMWATER CONTROL DAM ...... 20 6.4.1. EPC North ...... 20 6.4.2. EPC East ...... 20 6.4.3. EPC South ...... 20 6.4.4. Engineering properties of the soils are as follows: ...... 20 6.4.5. General recommendations ...... 21 6.5. GN704 STORMWATER UPGRADE MEASURES DESIGN CRITERIA AND PROJECT SCOPE STATEMENT ...... 21 6.6. CONCEPTUAL STORMWATER MANAGEMENT PLAN FOR EPC CONCENTRATOR ...... 22 6.7. CONCEPTUAL STORMWATER MANAGEMENT PLAN FOR EPL CONCENTRATOR ...... 22 6.8. GN704 STORMWATER UPGRADE MEASURES DESIGN CRITERIA AND PROJECT SCOPE STATEMENT ...... 23

7. TOPOGRAPHICAL SURVEY OF THE PROJECT SITE ...... 24 7.1. TOPOGRAPHICAL SURVEY ...... 24 7.2. DIGITAL TERRAIN MODEL ...... 24 7.3. INTERPRETATION OF TOPOGRAPHY ...... 24

8. CATCHMENT PROPERTIES AND HYDROLOGY ...... 25 E-TEK Consulting: RPT 100279 Page 6 LONMIN EASTERN PLATINUM – SURFACE WATER SPECIALIST REPORT

8.1. GENERAL CATHMENT PROPERTIES ...... 25 8.1.1. Vegetation ...... 25 8.1.2. geology ...... 26 8.2. CATCHMENT DELINEATION: ...... 26 8.3. HYDROLOGICAL DATA OF CONTRIBUTING AREAS ...... 27 8.4. ADOPTED FLOOD PEAKS AND VOLUMES ...... 28

9. CULVERT REVIEW ...... 29 10. FLOODLINES: STREAM HYDRAULIC ANALYSIS ...... 31 10.1. RIVER REACHES ...... 31 10.2. HYDRAULICS ...... 31 10.3. MANNING’S ROUGHNESS VALUE ...... 31 10.4. FROUDE NUMBER VALUE ...... 31 10.5. RESULTS ...... 32 10.6. INTERPRETATION ...... 33

11. COMPLIANCE WITH LEGISLATION ...... 33 11.1. FLOODLINES: REG. 4: RESTRICTIONS ON LOCALITY) ...... 33 11.2. 100 M EXCLUSION ZONE: REG. 4: RESTRICTIONS ON LOCALITY ...... 34 11.3. CLEAN AND DIRTY WATER SEPARATION: REG. 6: CAPACITY REQUIREMENTS OF CLEAN AND DIRTY WATER ...... 34 11.4. DRAINAGE: REG 7: PROTECTION OF WATER RESOURCES ...... 34 11.5. ROADS: REG 7: PROTECTION OF WATER RESOURCES...... 34 11.6. REUSE OF WATER (REGULATION 7: PROTECTION OF WATER RESOURCES) ...... 34

12. STORMWATER MANAGEMENT PLAN: INFRASTRUCTURE REQUIREMENTS ...... 34 12.1. POLLUTION CONTROL DAM ...... 34 12.2. PUMPSTATION ...... 35 12.3. SPILLWAY SIZING ...... 35 12.4. BUNDING AND ACCESS RAMPS ...... 35 12.5. CULVERT – SILT TRAP ...... 35

13. MANAGEMENT AND MITIGATION ...... 35 13.1.1. Construction phase requirements of the PLANT: ...... 35 13.1.2. Operational phase requirements of the PLANT:...... 36 13.1.3. Closure phase requirements of the Plant (active decommissioning): ...... 37

14. IMPACT ASSESSMENT ...... 38 14.1. IMPACT ASSESSMENT METHODOLOGY...... 38

15. REFERENCES ...... 43

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TABLE OF TABLES

TABLE 1: COMPLIANCE TO GN 704 REGULATION 4 ...... 5 TABLE 2: COMPLIANCE TO REGULATION 6: SUMMARY OF PROPOSED INFRASTRUCTURE REQUIREMENTS .... 5 TABLE 3: COMPLIANCE TO REGULATION 7: PROTECTION OF WATER RESOURCES ...... 5 TABLE 4: HISTORIC REPORTS AND INVESTIGATIONS ON THE EPL AND EPC CONCENTRATOR REGARDING COMPLIANCE WITH GN704 REGULATIONS...... 17 TABLE 5: SAFFY SHAFT CLEANWATER DIVERSION BUND CHARACTERISTICS ...... 18 TABLE 6: SAFFY SHAFT CULVERT CHARACTERISTICS ...... 18 TABLE 7: SAFFY SHAFT DIRTY WATER CATCHMENT CHARACTERISTICS ...... 18 TABLE 8: SAFFY SHAFT STORMWATER CHANNEL TO STORMWATER CONTAINMENT DAM ...... 18 TABLE 9: EPL PLANT CLEAN WATER DIVERSION BUND CHARACTERISTICS ...... 19 TABLE 10: EPL DIRTY WATER CATCHMENT AND REQUIRED STORMWATER CONTAINMENT DAM ...... 19 TABLE 11: EPC PLANT CLEAN WATER DIVERSION BUND CHARACTERISTICS ...... 19 TABLE 12: EPC DIRTY WATER CATCHMENT AND REQUIRED STORMWATER CONTAINMENT DAM ...... 19 TABLE 13: EPC PLANT DIRTYWATER CONTAINMENT BUND CHARACTERISTICS ...... 19 TABLE 14: EPL PLANT – UPGRADE STORMWATER DAM STORAGE REQUIREMENTS ...... 21 TABLE 15: DIRTY CATCHMENT CHARACTERISTICS AND PEAK FLOW RATES FOR 1:50-YEAR FLOOD EVENT .. 22 TABLE 16: DIRTY WATER CONTAINMENT FACILITY VOLUME REQUIREMENTS FOR 1:50-YEAR FLOOD EVENT 22 TABLE 17: DIRTY CATCHMENT CHARACTERISTICS AND PEAK FLOW RATES FOR 1:50-YEAR FLOOD EVENT .. 23 TABLE 18: DIRTY WATER CONTAINMENT FACILITY VOLUME REQUIREMENTS FOR 1:50-YEAR FLOOD EVENT 23 TABLE 19: EPL PLANT – UPGRADE STORMWATER DAM STORAGE REQUIREMENTS ...... 24 TABLE 20: ELEVATIONS TABLE ...... 25 TABLE 21: CONTRIBUTING CLEAN WATER CATCHMENT DATA ...... 26 TABLE 22: CONTRIBUTING DIRTY WATER CATCHMENT DATA ...... 27 TABLE 23: TR102 STORM RAINFALL DEPTHS ...... 27 TABLE 24: SMITHERS AND SHULZE STORM RAINFALL DEPTHS ...... 28 TABLE 25: FLOOD PEAKS OF THE CLEAN WATER CATCHMENTS ...... 28 TABLE 26: FLOOD PEAKS OF THE DIRTY WATER CATCHMENTS ...... 28 TABLE 27: PROPOSED SITE – STORMWATER DAM STORAGE REQUIREMENTS ...... 29 TABLE 28: CULVERT DATA ...... 29 TABLE 29: CULVERT IMAGERY ...... 30 TABLE 30: HEC-RAS OUTPUT TABLE ...... 32 TABLE 31: SPILLWAY SIZING ...... 35 TABLE 32: TABLE INDICATING THE SIGNIFICANCE CRITERIA ...... 39 TABLE 33: IMPACT ASSESSMENT – CONSTRUCTION PHASE ...... 40 TABLE 34: IMPACT ASSESSMENT – OPERATIONAL PHASE ...... 41 TABLE 35: IMPACT ASSESSMENT – DECOMMISSIONING AND CLOSURE PHASE ...... 42

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TABLE OF FIGURES

FIGURE 1: BASIC PRINCIPLES IN DEVELOPING A STORMWATER MANAGEMENT PLAN ...... 13 FIGURE 2: HIERARCHY OF WATER MANAGEMENT: LEVEL 1 AND 2 APPLICABLE TO THIS PROJECT ...... 14 FIGURE 3: LOCALITY OF LONMIN MARIKANA OPERATIONS RELATIVE TO MAIN ACCESS ROUTES ...... 15 FIGURE 4: LOCALITY OF THE PROJECT RELATIVE TO LONMIN MARIKANA OPERATIONS ...... 15 FIGURE 5: HEIGHT SHADING: MERGED GPS SURVEY AND LIDAR DATA ...... 25 FIGURE 6: LONG SECTION OF THE STREAM PASSING THE PROPOSED SITE ...... 33

APPENDICES

APPENDIX A: QUATERNARY CATCHMENTS ...... 44 APPENDIX B: DOLOMITIC AREAS ...... 45 APPENDIX C: RAINFALL AND STREAM FLOW STATIONS ...... 46 APPENDIX D: VEGETATION ...... 47 APPENDIX E: GENERAL ARRANGEMENT ...... 48 APPENDIX F: SRK STORMWATER MANAGEMENT PLAN ...... 49 APPENDIX G: EPC PLANT TEST PITS ...... 50 APPENDIX H: EPL PLANT TEST PITS ...... 51 APPENDIX I: PRAXOSS CC STORMWATER MANAGEMENT PLAN FOR EPC PLANT...... 52 APPENDIX J: PRAXOSS CC STORMWATER MANAGEMENT PLAN FOR EPL PLANT ...... 53 APPENDIX K: CONTRIBUTING CLEAN CATCHMENTS ...... 54 APPENDIX L: CONTRIBUTING DIRTY CATCHMENTS ...... 55 APPENDIX M: PROPOSED SITE LAYOUT ...... 56 APPENDIX N: 1 IN 100-YEAR FLOODLINE BOUNDARY...... 57 APPENDIX O: 100M EXCLUSION BOUNDARY ...... 58 APPENDIX P: CULVERT LAYOUT ...... 59 APPENDIX Q: DETAIL SITE LAYOUT...... 60 APPENDIX R: PCD LAYOUT ...... 61 APPENDIX S: TYPICAL DETAIL DRAWINGS OF PROPOSED INFRASTRUCTURE ...... 62 APPENDIX T: TYPICAL DESIGN OF CULVERT CROSSING ...... 63

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ACRONYMS AND SYMBOLS

ACRONYM EXPLANATION OR SYMBOL

ARM Alternative Rational Method

BPG Best Practice Guideline

C Runoff coefficient used in estimation of the flood peak (Rational Method) Curve number - index expressing a catchments storm flow response to a rainfall event CN (SCS method) DTM Digital terrain model

EPL Eastern Platinum Limited

EMV Earth moving equipment

FSL Full Supply Level

GIS Geographical Information Systems

GN 704 Government notice: Regulation 704 n Manning's roughness coefficient

NWA National Water Act, Act 36 of 1998 and its regulations

NOC Non overspill crest

NOL Normal operating level

Q Flow rate (m3/s)

SCS Soil Conservation System Technique

SDF Standard Design Flood Method

SoW Scope of work (s)

SWMP Stormwater Management Plan

Tc Time of concentration

# Shaft

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1. TERMS OF REFERENCE

Lonmin Eastern Platinum (Lonmin Marikana) has initiated an expansion project of the existing chrome plant. As part of the required EIA process, a specialist study is required relating to the hydrology of the site and stormwater management infrastructure requirements.

As required by legislation (Refer to §2), this document details the following:

• A conceptual stormwater management plan (SWMP) as part of the environmental impact assessment (EIA) process to be followed for the authorisation for the construction of the proposed chrome plant at Lonmin Marikana.

• Design criteria considered during the compilation of the stormwater management plan (SWMP) which includes all applicable legislative requirements;

• Drainage line exclusion zones for construction as described in legislation;

• Layout drawings and conceptual designs related to the SWMP;

• Impact assessment.

2. LEGISLATIVE REQUIREMENTS

The following legislation and guidelines were considered as relevant to this project:

• National Water Act (NWA) Act 36 of 1998 and its regulations;

o Specific reference to the requirements of the Department of Water Affairs and Forestry (DWAF) Government Notice No. 704 (GN –704);

o Guideline Document for the Implementation of Regulations on Water Use of Mining and Related Activities Aimed at the Protection of Water Resources;

• National Environmental Management: Waste act NEM: WA;

• National Norms and Standards;

• National Environmental Management Act (NEMA) Act 107 of 1998 and its regulations.

Special attention is drawn to the following Regulations within GN704 of the NWA:

2.1. EXTRACTS FROM GN704 APPLICABLE TO THIS PROJECT

Only the applicable regulations have been listed below.

2.1.1. REGULATION 4: RESTRICTIONS ON LOCALITY

No person in control of a mine or activity may-

a) locate or place any residue deposit, dam, reservoir, together with any associated structure or any other facility within the 1:100-year flood-line or within a horizontal distance of 100 metres from any watercourse or estuary, borehole or well, excluding boreholes or wells drilled specifically to monitor the pollution of groundwater, or on water-logged ground, or on ground likely to become water-logged, undermined, unstable or cracked;

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2.1.2. REGULATION 6: CAPACITY REQUIREMENTS OF CLEAN AND DIRTY WATER SYSTEMS.

Every person in control of a mine or activity must

a) confine any unpolluted water to a clean water system, away from any dirty area; b) design, construct, maintain and operate any clean water system at the mine or activity so that it is not likely to spill into any dirty water system more than once in 50 years; c) collect the water arising within any dirty area, including water seeping from mining operations, outcrops or any other activity, into a dirty water system;

d) design, construct, maintain and operate any dirty water system at the mine or activity so that it is not likely to spill into any clean water system more than once in 50 years; and f) design, construct and maintain all water systems in such a manner as to guarantee the serviceability of such conveyances for flows up to and including those arising as a result of the maximum flood with an average period of recurrence of once in 50 years.

2.1.3. REGULATION 7. PROTECTION OF WATER RESOURCES.

Every person in control of a mine or activity must take reasonable measures to a) prevent water containing waste or any substance which causes or is likely to cause pollution of a water resource from entering any water resource, either by natural flow or by seepage, and must retain or collect such substance or water containing waste for use, re-use, evaporation or for purification and disposal in terms of the Act; b) design, modify, locate, construct and maintain all water systems, including residue deposits, in any area so as to prevent the pollution of any water resource through the operation or use thereof and to restrict the possibility of damage to the riparian or in-stream habitat through erosion or sedimentation, or the disturbance of vegetation, or the alteration of flow characteristics;

f) ensure that water used in any process at a mine or activity is recycled as far as practicable, and any facility, sump, pumping installation, catchment dam or other impoundment used for recycling water, is of adequate design and capacity to prevent the spillage, seepage or release of water containing waste at any time; h) cause all domestic waste, including wash-water, which cannot be disposed of in a municipal sewage system, to be disposed of in terms of an authorisation under the Act. The re-use of mine-influenced water is now recognised as best practice worldwide and the majority of major mining companies have embodied this principle within their codes of conduct. In many cases, the advantages of re-using or recycling mine-influenced water are substantial.

3. PRINCIPLES OF STORM WATER MANAGEMENT AND HIERARCHY OF DECISION TAKING

3.1. PRINCIPLES OF STORM WATER MANAGEMENT

There are four primary principles to consider and apply, where possible, during the development of an SWMP (Figure 1) (Department of Water Affairs and Forestry; Directorate: Resource Protection and Waste, June 2006).

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Principle 1: Keep Clean Water Clean •Identify & where possible maximise areas that will discharge clean runoff & route runoff from these areas directly to natural watercourses without containing or contaminating the runoff. • Clean runoff must only be contained if the runoff volume poses a risk, if the runoff cannot be discharged to a watercourse by gravitation, for attenuation purposes or when the clean area is small and located within a dirty area. This water must be released under controlled conditions. Principle 2: Collect & Contain Dirty Water

•Minimise contaminated areas, reuse dirty water where possible & plan not to lose clean areas to the catchment unnecessarily. •Minimise seepage losses from storage facilities & prevent overflows. •Identify all possible sources of dirty water & implement appropriate collection & containment facilities. Ensure that dirty areas do not result in further unnecessary water quality deterioration. •Contained dirty water must be managed according to the hierarchy of water management. •Moderately polluted water must not be polluted further. Where possible this should be separated from more polluted water. This will assist in the reuse water strategy and also reduce the quantities of water requiring treatment. Principle 3: Sustainability over Mine Cycle •Ensure commitment from management & staff, inter alia make adequate human & financial resources available to implement the SWMP. •Formulate SWMP concurrently with the planning & layout of infrastructure - ensure it takes account of all life cycle phases from planning to post-closure. •Identify & quantify the risk of failure of components of the SWMP & the consequences of such failure. •Consider possible changes or upgrades (additional facilities, expansions etc.) that might occur during the life cycle of the operation. Principle 4: Consideration of Regulations & Stakeholders •Identify legislation relevant to the environment & water resources & ensure compliance. •Include effective liaison with DWA. •Communicate & liaise with the CMA. •Incorporate the constitutional rights of the environment & other users of the water resource by ensuring that:. •During the course of operations that up- and downstream users are not adversely affected. •Sensitive habitats & landscapes are identified & protected. •The operation commits to progressive improvement to the water quality where it is being affected by the operations. •The concerns of I&APs are addressed. •There is transparency and a flow of information to the I&APs. Additional General Principles •At the end of the operations, the company has a plan that can be implemented to sustain & protect the reserve, as well as the water quality & quantity up- and downstream of the operations. • catchment based approach to SWMP should be followed. •Appropriate technical studies to adequate standards must be undertaken to understand the storm water system. •A range of management measures & options should be considered before a final choice is made. •Performance indicators must be set & implemented, e.g. the operating level of a SWD to allow for storm water events. •Finalisation of the SWMP should be followed implementation, operation, monitoring & auditing. •The effective training of staff & their roles & responsibilities in terms of the SWMP is the key to success or failure of the SWMP.

Figure 1: Basic principles in developing a stormwater management plan

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3.2. HIERARCHY OF DECISION-TAKING WITH RESPECT TO STORM WATER MANAGEMENT

The basis of integrated water and waste management at similar mining operations is based on the Department of Water and Sanitation Resource Protection and Waste Management hierarchy of decision-taking. (Figure 2). This hierarchy is based on a precautionary principle and sets the following order of priority for water and waste management decisions and/or actions.1.

This project aims to manage surface water up to the first two levels of the hierarchy.

Prevent or minimise pollution / contamination of water used by implementing necessary management measures or strategies

Reuse or Reclaim contaminated water in cases where complete pollution prevention was not possible

Treat water that cannot be reused or reclaimed

Reuse treated water

Discharge or Disposal of excess Water

Figure 2: Hierarchy of water management: Level 1 and 2 applicable to this project

4. LOCALITY OF THE SITE

The site is situated about 9km from Marikana and 20km from Brits.

The coordinates of the site are approximately 25°41'33.99"S 27°37'6.63"E (Figure 3 and Figure 4). The project site is within the mine lease area of Lonmin Marikana.

1 Department of Water Affairs and Forestry; Directorate: Resource Protection and Waste. (June 2006). Best Practice Guideline G1: Storm Water Management.

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Figure 3: Locality of Lonmin Marikana Operations relative to main access routes

Figure 4: Locality of the project relative to Lonmin Marikana Operations

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5. SITE VISIT

Site visits were conducted in November 2017 and January 2018. The objectives of the visits were the following:

• Get a better understanding of current infrastructure upstream of the proposed project site and the proposed infrastructure layout;

• Gather information on vegetation, topography and soil conditions that influence runoff characteristics (including floodline delineation);

• Gather information on the water balance requirements and pumping capacities;

• To assess the site for the proposed expansion project in terms of potential surface water impacts during construction and operations.

6. BACKGROUND INFORMATION AFFECTING THE PROJECT

6.1. TOPOGRAPHY, CLIMATE, VEGETATION AND GEOLOGY,

This information is detailed in the paragraphs listed below.

Refer to § 7:Topography;

Refer to § 8.1.1: Vegetation;

Refer to § 8.1.2: Geology;

Refer to § 8.3: Climate.

6.2. INFRASTRUCTURE WITHIN CATCHMENTS UPSTREAM OF THE PROJECT SITE

The catchments upstream of the proposed expansion project have an impact on the management of surface flow runoff at the proposed project site and the floodlines in the drainage line.

NOTE: The information below has been collated in order to inform the reader of designed infrastructure due or in process of being constructed.

All the subsequent SWMP designs for Lonmin Marikana Operations – Eastern Platinum Limited – EPL Chrome Plant have been based on the assumption that this infrastructure has been installed and the impact on the hydrology has been taken into account.

Lonmin Marikana has in the past appointed various consultants to compile SWMP management plans for Saffy Shaft, EPC and EPL concentrator sites and quoted as follows. These areas now have an impact on the SWMP of the proposed project as the infrastructure, described in the reports referenced in Table 4 below, have yet to be completed. Refer to APPENDIX E: GENERAL ARRANGEMENT

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Table 4: Historic reports and investigations on the EPL and EPC concentrator regarding compliance with GN704 regulations.

REPORT NR REPORT HEADING CONSULTANT DATE NUMBER March 3.1 GN704 Stormwater Management Plan 355395/1 SRK 2006 Geotechnical Investigation for August 3.2 proposed new EPC GN704 413752/2 SRK 2010 Stormwater Control Dam GN704 Stormwater Upgrade 413752/2- December 3.3 Measures Design Criteria and Project SRK rev01 2011 Scope Statement Conceptual Stormwater Management November 3.4 - Praxos 741 CC Plan for EPC Concentrator 2012 Conceptual Stormwater Management November 3.5 - Praxos 741 CC Plan for EPL Concentrator 2012 GN704 Stormwater Upgrade 3.6 Measures Design Criteria and Project May 2015 SRK May 2015 Scope Statement

6.3. GN704 STORMWATER MANAGEMENT PLAN FOR EASTERN PLATINUM LIMITED

Lonmin Marikana appointed SRK Consulting to compile a SWMP for Eastern Platinum Limited (EPL) to achieve full compliance with regulation GNR704 at the following facilities.

The facilities include #1, Saffy, Hossy and Newman Shaft, EPL and EPC Plants, Central Workshop and Bus Depot. Note that Saffy and Hossy shafts fall outside the quaternary catchment of this study. Refer to Key findings at Saffy Shaft, EPC and EPL Plant (Refer to APPENDIX E):

6.3.1. SAFFY SHAFT

The proposal

• Construct clean water diversion bund upstream of the shaft area together with a concrete speedbump across the ramp access to the shaft to limit clean stormwater accessing the cut-off channel. The diversion bund is to terminate downstream of the soccer fields adjacent to the Hostels. • Construct a road culvert where the clean water diversion bund crosses a proposed new surfaced road running along the northern boundary of the Saffy site. • Apply for exemption in Water Use License Application (WULA) given that the available storage to contain the 1:50-year storm event is insufficient. If exemption is not approved, the existing stormwater dam should be upgraded with increased storage capacity and a HDPE liner to allow stormwater to gravitate from the Saffy Shaft cut-off channel via a trapezoidal concrete-lined channel. This will prevent spillage from the cut-off channel discharging into the environment. The upgrade is to incorporate and a pump station delivering stormwater to the Erikson Tank via a 100MM mPVC pipeline. • Construct evaporation paddocks to collect runoff from the waste rock dump.

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Table 5: Saffy Shaft cleanwater diversion bund characteristics

BOTTOM LENGTH DEPTH TOP WIDTH SITE WIDTH (m) (m) (m) (m)

Bund-Saffy 307 0.5 1.0 4.0 Shaft

Table 6: Saffy Shaft culvert characteristics

1:50-YEAR BOTTOM ROUGHNESS DEPTH NO OF SITE FLOW WIDTH “n” (m) CULVERTS RATE (m) (m³/s) Saffy Shaft 1.38 0.013 0.9 0.9 2

Table 7: Saffy Shaft dirty water catchment characteristics

1:50-YEAR SHAFT AVERAGE 1:50-YEAR FLOW SITE AREA SLOPE CN VOL RATE (m²) (m/m) (m³) (m³/s) Saffy Shaft 62.677 0.002 98 2.2 12,300

Table 8: Saffy Shaft stormwater channel to stormwater containment dam

CHANNEL CHANNEL BOTTOM FLOW DEPTH SITE LENGTH SLOPE WIDTH RATE (m) (m) (m/m) (m) (m³/s) Saffy 170 0.002 0.5 0.9 2.2 Channel

6.3.2. EPL PLANT

• Construct a clean stormwater diversion bund upstream of the plant terminating at an existing road culvert to allow clean stormwater to discharge into the watercourse; • Discontinue the use of the existing EPL plant surge dams for stormwater storage and consider removing the dams for processing within the plant; • Construct a lined stormwater dam large enough to contain dirty stormwater for the 1:50-year storm event and other plant spillage and overflow. The stormwater dam is to be constructed with a double Hyson-cell lining with a bitumen inter-layer to allow earth moving equipment (inter-layer) access for sediment removal and prevention of dirty water ingress into the groundwater. The dam is to incorporate a pump station delivering stormwater back to the plant Thickeners via a 100mm mPVC pipeline. The lined stormwater dam is to be sited adjacent to the EPC access road with final location determined following clarification on the extent of the proposed chrome plant and stockpile; • Construct evaporation paddocks to collect runoff from the rock dump.

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Table 9: EPL plant clean water diversion bund characteristics

LENGTH DEPTH TOP WIDTH BOTTOM SITE (m) (m) (m) WIDTH (m) Bund-EPL 300 1.0 1.0 4.0 plant

Table 10: EPL dirty water catchment and required stormwater containment dam

PLANT STORAGE AVERAGE DAM LINER SITE AREA VOLUME DEPTH AREA (m²) TYPE (m²) (m³) (m) Bund-Saffy Hyson- 103,750 20,125 15,450 2.5 Shaft cell

6.3.3. EPC PLANT

• Construct a clean stormwater diversion bund from the rock dump between EPL and EPC plants. • Upgrade the existing stormwater containment pond by increasing the storage capacity and lining with a double Hyson-cell lining with bitumen interlayer to allow EMV access for sediment removal and prevention of dirty water ingress into the groundwater. The dam is to incorporate a pump station delivering stormwater back to the plant thickeners via a 100mm PVC pipeline. • Construct clay-lined stormwater containment bunds to convey dirty overland flow to the upgraded stormwater containment pond and prevent discharge into the environment.

Table 11: EPC plant clean water diversion bund characteristics

LENGTH DEPTH TOP WIDTH BOTTOM SITE (m) (m) (m) WIDTH (m) Bund-EPL 170 0.5 1.0 2.5 plant

Table 12: EPC dirty water catchment and required stormwater containment dam

PLANT STORAGE DAM AVERAGE LINER SITE AREA VOLUME AREA DEPTH TYPE (m²) (m³) (m²) (m) Bund-Saffy Hyson- 94,170 18,300 6,240 4.1 Shaft cell

Table 13: EPC plant dirtywater containment bund characteristics

BOTTOM LENGTH DEPTH TOP WIDTH SITE WIDTH (m) (m) (m) (m) Northern Bund 320 1.0 1.0 4.0 Southern Bund 95 1.0 1.0 4.0

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6.4. GEOTECHNICAL INVESTIGATION FOR PROPOSED NEW EPC GN704 STORMWATER CONTROL DAM

SRK Consulting has been appointed to carry out the design of the proposed new EPC GN704 stormwater control dam for Lonmin Marikana.

As part of the consulting services, SRK undertook a geotechnical investigation to determine the prevailing geological and geotechnical conditions on site.

The objective of this geotechnical investigation was to identify the predominant soil types encountered below the site and determine their engineering properties with respect to construction of the dam.

Key findings at EPC Plant stormwater control dam (Refer to APPENDIX G):

6.4.1. EPC NORTH

• Black turf extends to 1.0m below ground surface;

• No residual soils present, bedrock at approximately 1.0m;

• No groundwater seepage observed.

6.4.2. EPC EAST

• Black turf extends to 1.0m below ground surface;

• Residual soils variable developed to depths of between 1.3m and 2.0m. Bedrock encountered between 1.5m and 2.0m;

• Groundwater seepage observed at 1.5m.

6.4.3. EPC SOUTH

• Black turf extends to between 1.2m and 1.4m below ground surface;

• Residual soils developed to depths of between 1.4m and 3,4m;

• Shallow bedrock outcrops encountered from surface. Bedrock encountered from 1.4m to 3,4m in the test pits;

• Groundwater seepage observed from 2.2m to 3,4m.

6.4.4. ENGINEERING PROPERTIES OF THE SOILS ARE AS FOLLOWS:

• The site is underlain by a mantle of clayey black turf soils which are potentially highly expansive. The soils have an average thickness of approximately 1.0m and grade to residual norite. The residual norite however is poorly developed across the footprint of the study area and was only encountered below the EPC South and partially below the EPC East sites;

• The ubiquitous developed clayey black turf soils have a plasticity index of 37% and a liquid limit range of 63% with a clay content of about 40%;

• The cohesive black turf soils are practically impermeable but have moderate in-situ shear strength characteristics. These soils are more suitable for starter walls and embankments than the sandy residual norite;

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• The plasticity indices and liquid obtained from the residual norite samples are generally variable between non-plastic and 32%. These soils have low potential expansiveness and clay content between 2% and 8%. The estimated in-situ permeability of these soils is approximately 10-5m/s to 10-6m/s which equates to poor drainage. These soils are less suitable for starter walls and embankments than the clayey black turf materials;

• The conclusion on shear strength characteristics is that the rate of testing of the one sample was too high and that the actual values to be used should be ɸ=19o to 22o. Usually the cohesion for such materials is zero, as the density is too low to develop a proper cohesion.

6.4.5. GENERAL RECOMMENDATIONS

• Strip and stockpile the upper 300mm topsoil layer for rehabilitation purposes;

• Remove all mounds of stockpiled materials. Stockpile the fill material for use in the embankment;

• Place fill material in layers not exceeding 150mm and compact to 95% of Proctor maximum dry density at the materials optimum moisture content;

• Slope embankment to 1v:3h;

• Install a geomembrane lining system across prepared earth-fill embankment and dam basin;

• Vegetate exposed slopes of embankment to reduce erosion and install appropriate drainage measures such as drains and stormwater berms around perimeter of embankment.

6.5. GN704 STORMWATER UPGRADE MEASURES DESIGN CRITERIA AND PROJECT SCOPE STATEMENT

Lonmin Marikana appointed SRK Consulting during 2006 to compile a comprehensive SWMP for the Eastern Platinum Limited (EPL) operations such that the subsequent implementation of this plan will achieve full compliance with Regulation 704 (GN704) of the National Water Act (NWA, Act 36, 1998). The investigation addressed various EPL infrastructure including the EPL Plant. The final report (Report 355395/1, 2006) recommended that upgrading of the stormwater drainage system needs to be undertaken in order for EPL to meet GN704 of the NWA.

The measures detailed in this report, once constructed, will contribute to the EPL Plant meeting GN704 requirements. Stormwater generated upstream of EPL Plant will be diverted away from the site. Dirty water generated at the EPL Plant will be contained on site.

Table 14: EPL Plant – upgrade stormwater dam storage requirements

SITE AREA REQUIRED STORAGE VOLUME NAME (m²) (m³) 1: 50-YEAR OPERATIONAL EPL Plant 232,500 33,800 5,070 Total required storage volume 33,800

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6.6. CONCEPTUAL STORMWATER MANAGEMENT PLAN FOR EPC CONCENTRATOR

Praxos 741 CC has been appointed by Lonmin Marikana to develop an overarching Water Conservation/Water Demand Management Strategy for the Lonmin Marikana Operations. The scope of this project includes the need to assess/develop appropriate conceptual stormwater management plans for each operation at Lonmin Marikana. These plans will also form an important component of Lonmin Marikana’s Integrated Water Use License Application (IWULA), submitted to the Department of Water Affairs (DWA).

Key findings (Refer to APPENDIX I):

• It is recommended that discussions are held with the DWA regarding the lining requirements for stormwater management infrastructure, to ensure that the flood hydrology calculations can be revised accordingly during detailed design and prior to construction of infrastructure.

• It is recommended that additional storage capacity be considered at the proposed stormwater dam during the detail design phase to accommodate additional operational storage volume.

Table 15: Dirty catchment characteristics and peak flow rates for 1:50-year flood event

TIME OF PEAK FLOW AREA CATCHMENT CONCENTRATION RATE (km²) (minutes) (m3/s) Dirty Water A 0.106 21 3.1

Table 16: Dirty water containment facility volume requirements for 1:50-year flood event

MINIMUM VOLUME CATCHMENT NAME (m3)

Dirty Water A 12,795

6.7. CONCEPTUAL STORMWATER MANAGEMENT PLAN FOR EPL CONCENTRATOR

Praxos 741 CC has been appointed by Lonmin Marikana to develop an overarching Water Conservation/Water Demand Management Strategy for the Lonmin Marikana Operations. The scope of this project includes the need to assess/develop appropriate conceptual stormwater management plans for each operation at Lonmin Marikana. These plans will also form an important component of Lonmin Marikana’s Integrated Water Use License Application (IWULA), submitted to the Department of Water Affairs (DWA).

Key findings (Refer to APPENDIX J):

• It is recommended that discussions are held with the DWA regarding the lining requirements for stormwater management infrastructure, to ensure that the flood hydrology calculations can be revised accordingly during detailed design and prior to construction of infrastructure;

• It is recommended that additional storage capacity be considered at the proposed stormwater dam during the detail design phase to accommodate additional operational storage volume.

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Table 17: Dirty catchment characteristics and peak flow rates for 1:50-year flood event

TIME OF PEAK FLOW AREA CATCHMENT CONCENTRATION RATE (km²) (minutes) (m3/s) Dirty Water A 0.129 23 4.0

Table 18: Dirty water containment facility volume requirements for 1:50-year flood event

MINIMUM VOLUME CATCHMENT NAME (m3)

Dirty Water A 16,169

6.8. GN704 STORMWATER UPGRADE MEASURES DESIGN CRITERIA AND PROJECT SCOPE STATEMENT

Lonmin Marikana appointed SRK Consulting during 2006 to compile a comprehensive stormwater management plan for the Eastern Platinum Limited (EPL) operations such that the subsequent implementation of this plan will achieve full compliance with Regulation 704 (GN704) of the National Water Act (NWA, Act 36, 1998). The investigation addressed various EPL infrastructure including the EPL Plant. The final report (Report 355395/1, 2006) recommended that upgrading of the stormwater drainage system needs to be undertaken in order for EPL to meet GN704 of the NWA.

The measures detailed in this report, once constructed, will contribute to the EPL Plant meeting GN704 requirements. Stormwater generated upstream of EPL Plant will be diverted away from the site. Dirty water generated at the EPL Plant will be contained on site.

Key findings:

• The re-construction of the existing earth channel from the south-eastern corner of the plant to the position of the new stormwater dam. The new channel will be constructed using 75mm thick 3D Bubble Lock Hyson Cells filled with 25/19mm strength concrete. The Hyson Cells will be constructed on a 25mm thick sand bedding layer;

• Construction of the new lined stormwater dam with storage capacity of 33,800m3 at Full Supply Level (FSL). A weir overflow will be constructed at FSL. The dam will be 3.4m deep with 1:3 side slopes. The dam will be divided in 2 compartments with a dividing wall separating the compartments. The smaller compartment will act as a silt trap and will be lined with two layers of 75mm 3D Bubble Lock Hyson Cells with a 3mm thick bitumen waterproofing layer between them. An access ramp with slopes 1:10 will enable small machines to access this compartment to clean out the silt. The liner will be cast on a 25mm sand layer overlaying a leakage detection system comprising an A7 nonwoven geotextile top layer, 75mm thick washed 19mm stone layer and a Viasel bitumen impregnated Waterblok bottom layer. A drainage network consisting of M65 geo- pipes will discharge via a 160mm ND PE100 Class 10 HDPE pipe to a sump constructed on the eastern side of the new stormwater dam. EPL Plant will provide a submersible pump at the manhole with a pipeline to the stormwater dam;

• At request of the mine, the design of the bigger compartment was altered from the two layers of 75mm 3D Bubble Lock Hyson Cell layers to comprise a multi-layer HDPE system. This consists E-TEK Consulting: RPT 100279 Page 23 LONMIN EASTERN PLATINUM – SURFACE WATER SPECIALIST REPORT

of the 2mm HDPE on top of a Hydrain 750 cuspated sheet that is underlain by a 1.5mm HDPE sheet that is at least mono textured;

• Based on the limited suite of analysis available, the water in the EPL dam classified as a Type 3, which would require disposal in a facility with a barrier system that meets the requirements of a Class C barrier system.

Table 19: EPL Plant – upgrade stormwater dam storage requirements

SITE AREA REQUIRED STORAGE VOLUME NAME (m²) (m³)

1:50-YEAR OPERATIONAL

EPL Plant 232,500 33,800 5,070

Total required storage volume 33,800

7. TOPOGRAPHICAL SURVEY OF THE PROJECT SITE

7.1. TOPOGRAPHICAL SURVEY

A site topographical survey conducted in November 2017 together with Lidar data obtained from relevant software was used for the compilation of a digital terrain model used for the determination of the floodlines skirting the proposed project site.

7.2. DIGITAL TERRAIN MODEL

The survey and Lidar data were merged and then utilised to build a digital terrain model (DTM) of the area under consideration (Figure 5). An aerial image was used as a backdrop for the survey data to support a visual interpretation of the site. Further calculations of the floodlines and exclusion zones were based on this data.

7.3. INTERPRETATION OF TOPOGRAPHY

The terrain has an average surface slope of 3-10%. This was derived from the contours generated from the data obtained. Depicted in Figure 5 are the computer-generated elevations. The resultant drainage of the area is in an eastern direction.

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Figure 5: Height shading: merged GPS survey and Lidar data

Table 20: Elevations table

MINIMUM MAXIMUM AREA COLOUR ELEVATION ELEVATION (ha) (m) (m) 1140.79 1146.74 14,41

1146.74 1149.690 11,49

1149.69 1151.990 9,49

1151.99 1162.300 8,39

8. CATCHMENT PROPERTIES AND HYDROLOGY

8.1. GENERAL CATHMENT PROPERTIES

8.1.1. VEGETATION

Refer to APPENDIX D.

The proposed site (Refer to APPENDIX E and APPENDIX M) is found within the savanna biome which is the largest terrestrial biome in and it consists out of a mixture of a lower grass layer and an upper woody layer (which usually covers less than 75% of the area). If the woody component is dense in savanna areas, it is usually referred to as “bushveld”. The amount of woody species are also largely determined by fire and grazing and this should be managed to lessen the chance of bush encroachment. (Van Oudthoorn, 2012) .

The bioregion in which the Lonmin EPC is found is described by (Mucina and Rutherford, 2006), as the Central Bushveld Bioregion and the specific vegetation unit where the Lonmin EPC is found is described as the Marikana Thornveld. According to Mucina and Rutherford (2006), the vegetation unit

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is also described as a mixture of Sourish Mixed Bushveld and Other Turf Thornveld by Acocks (1953) as well as Clay Thornveld by Low and Rebelo (1996).

The Marikana Thornveld vegetation unit consists mainly out of open woodland areas comprising mostly out of Vachellia karroo (Sweet thorn) trees. Areas where shrubs are denser include rocky outcrops as well as next to drainage lines and other areas where fire cannot easily control the woody species. Other tree species in the area include Senegalia burkei (Black monkey thorn), Searsia lancea (Karee) and Ziziphus mucronata (Buffalo thorn). Shrubs include Olea europaea subsp. africana (Wild olive), Euclea crispa subsp. crispa (Blue guarri) and Grewia flava (Raisin bush). Grass species in the area include Themeda triandra (Red grass), Eragrostis lehmanniana (Lehmann’s love grass), Setaria sphacelata (Bristle grass) and Melinis nerviglumis (Bristle-leaved red-top) (Mucina & Rutherford, 2006; Van Oudtshoorn, 2012).

8.1.2. GEOLOGY

Refer to APPENDIX B indicating that the site is not within a dolomite area..

The proposed site (refer to APPENDIX E and APPENDIX M) is located in the Bushveld Complex. The Bushveld Complex holds most of the world’s chromium, platinum (Merensky Reef and UG2 are two layers found in the Bushveld Complex containing platinum), vanadium and refractory minerals. It has three components, namely the Layered Suite, Lebowa Granite Suite and the Rooiberg Group. Rocks in the Complex consists out of volcanic rocks as well as basaltic magmas which created a large chamber underground. After the intrusion of basalt, another rock intruded the primary rocks, namely granite. The Complex was then covered by sedimentary rocks which have been eroded to expose the present day geologic formations of the Complex. (McCarthy, 2005). Basaltic rocks typically weather into basic (alkaline) soils with a higher clay content, while granite rocks weather into more acidic sandy soils with a low clay content. Soils in the area include mainly vertic melanic clays with some dystrophic or mesotrophic plinthic catenas and some areas consisting out of free draining deep soils (Mucina and Rutherford, 2006)

8.2. CATCHMENT DELINEATION:

The hydrology of the clean water catchments upstream of the proposed site (Refer to APPENDIX E and APPENDIX M) was investigated and the peak flows associated with the 24-hour storms of various recurrence intervals were calculated.

Table 21: Contributing clean water catchment data

CATCHMENT ABBREVIATED AREA HYDRAULIC AVERAGE WEIGHTED NAME CATCHMENT (ha) LENGTH SLOPE CURVE NAME (km) (m/m) NUMBER

Clean CC-A 7.99 0.658 0.013 70 Catchment A Clean CC-B 10.91 0.718 0.011 76 Catchment B Clean CC-C 2.14 0.392 0.010 79 Catchment C Clean CC-D 4.23 0.318 0.021 70 Catchment D Clean CC-E 34.35 1.428 0.017 70 Catchment E E-TEK Consulting: RPT 100279 Page 26 LONMIN EASTERN PLATINUM – SURFACE WATER SPECIALIST REPORT

CATCHMENT ABBREVIATED AREA HYDRAULIC AVERAGE WEIGHTED NAME CATCHMENT (ha) LENGTH SLOPE CURVE NAME (km) (m/m) NUMBER

Clean CC-F 185.18 2.680 0.016 73 Catchment F Clean CC-G 153.79 2.369 0.017 72 Catchment G Clean CC-H 53.23 1.336 0.015 77 Catchment H

Refer to the reference map of the clean water catchment layout in APPENDIX K.

Table 22: Contributing dirty water catchment data

CATCHMENT ABBREVIATED AREA HYDRAULIC AVERAG WEIGHTED NAME CATCHMENT (ha) LENGTH E SLOPE CURVE NAME (km) (m/m) NUMBER

Dirty Catchment A DC-A 10.6 570 0.008 83

Dirty Catchment DC-B & DC-C 21 857 0.008 83 B-C Dirty Catchment D DC-D 6.268 300 0.002 89

Dirty Catchment E DC-E 3.620 0.280 0.010 98

Refer to the reference map of the dirty water catchment in APPENDIX L.

8.3. HYDROLOGICAL DATA OF CONTRIBUTING AREAS

The closest rainfall stations are Wolhuters (512344) (Refer to APPENDIX C) which is approximately 9.7 km from the proposed site (Refer to APPENDIX E and APPENDIX M). The stations have 54 years of rainfall records and a mean annual precipitation of 701 mm. The highest elevation of the catchments considered is approximately 1149m above sea level.

The site is located in quaternary catchment A21J (refer to APPENDIX A), in the Crocodile River catchment near dam.

Table 23: TR102 storm rainfall depths

DURATION RETURN PERIOD (DAYS) 2 5 10 20 50 100 200 24hr 71 100 123 149 186 219 255 1 Day 64 90 111 134 168 197 230 2 Days 82 118 146 178 224 264 309 3 Days 90 128 158 190 237 277 322 7 Days 116 168 209 252 316 370 429

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Table 24: Smithers and Shulze storm rainfall depths

DURATION RETURN PERIOD (DAYS) 2 5 10 20 50 100 200 24hr 69 93 111 129 154 175 196 1 Day 62 84.1 100.1 116.4 139.1 157.5 177 2 Days 76.5 104.7 124.8 145.6 174.3 197.5 222 3 Days 87 118.6 141.3 164.4 196.5 222.1 249.3 7 Days 113.4 154.8 183.7 212.9 252.8 284.2 316.9

8.4. ADOPTED FLOOD PEAKS AND VOLUMES

The magnitude of the flood peaks is dependent on the catchment characteristics, rainfall and existing stormwater control measures.

Determination of flood peaks was performed using four different methods. Methods used were the Alternative Rational method (ARM), Standard Design Flood (SDF) method, Soil Conservation System Technique (SCS) method and the SCS-TR55.

Table 25: Flood peaks of the clean water catchments

CLEAN CATCHMENT ESTIMATED 1:50-YEAR ESTIMATED 1IN100-YEAR NUMBER PEAK FLOW PEAK FLOW (m³/s) (m³/s) CC-A 1.22 1.52 CC-B 3.25 3.93

CC-C 0.87 1.04 CC-D 1.05 1.31 CC-E 6.49 8.08 CC-F 21.98 27.04 CC-G 19.58 24.12 CC-H 11.44 13.85

Table 26: Flood peaks of the dirty water catchments

DIRTY CATCHMENT ESTIMATED 1:50-YEAR ESTIMATED 1IN100-YEAR NUMBER PEAK FLOW (m³/s) PEAK FLOW (m³/s)

DC-A 4.06 4.78 DC-B&C 6.77 8 DC-D 2.84 3.23 DC-E 2.01 2.29

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Table 27: Proposed Site – stormwater dam storage requirements

DIRTY CATCHMENT SITE AREA REQUIRED STORAGE VOLUME NUMBER (m²) (m³) 1:50-YEAR OPERATIONAL2 DC-E 32,200 5,350 2,150 Total required storage volume 7,500

9. CULVERT REVIEW

APPENDIX P depicts the position of existing culverts affecting the floodlines near the proposed site. Table 28 indicate all the parameters of the existing culverts with the pictures depicted in Table 29.Table 28: Culvert data

Table 28: Culvert data

CULVERT CULVERT THROUGH FLOW CULVERT INSIDE INSIDE QUANTITY SHAPE MATERIAL BEFORE NAME WIDTH HEIGHT OVERTOPPING (m) (m) (m3/s)

C1-2 1 Box 2.2 0.8 Concrete 3.0

C3-C4 1 Box 1.0 0.6 Concrete 1.5

C9-C10 1 Box 1.4 1.4 Concrete N/A

C12-C13 1 Box 3.0 1.6 Concrete N/A

C14-C15 1 Box 1.4 1.2 Concrete 4.0

C16-C17 1 Round 0.6 (Diameter) Concrete 1.0

C20-C21 2 Round 0.6 (Diameter) Steel 1.98

C22-C23 1 Box 2.3 1.7 Concrete N/A

C24-C25 2 Box 1.1 1.1 Concrete 7.4

2 Supplied by Glencor – P. Magee (9 Jan 2018)

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Table 29: Culvert imagery

CULVERT PHOTO 1 PHOTO 2 NR

C1-2

C3-C4

C9-C10

C12-C13

C14-C15

C16-C17

C20-C21

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CULVERT PHOTO 1 PHOTO 2 NR

C22-C23

C24-C25

10. FLOODLINES: STREAM HYDRAULIC ANALYSIS

10.1. RIVER REACHES

Only one non-perennial stream passes the proposed site (refer to APPENDIX E and APPENDIX M) and analysed accordingly.

10.2. HYDRAULICS

The hydraulic calculations were performed using HEC-RAS (version 4.1.0) a computer program that models the hydraulics of water flow through natural rivers.3

10.3. MANNING’S ROUGHNESS VALUE

The manning’s coefficient determines the frictional resistance of the conveyance structure and is a dimensionless value determined by Chow (1959). The roughness value of certain sections was captured during the site visit and evaluated independently from one another. A roughness value was allocated to each cross-section and incorporated into the design software.

10.4. FROUDE NUMBER VALUE

The Froude number is a dimensionless number and is determined to illustrate the flow conditions in the conveyance structures.

푄2퐵 퐹푅2 = 푔퐴3

퐹푅 = 퐹푟표푢푑푒 푛푢푚푏푒푟 푑𝑖푚푒푛푠𝑖표푛푙푒푠푠 푛푢푚푏푒푟

푚3 푄 = 퐷𝑖푠푐ℎ푎푟푔푒 𝑖푛 푡ℎ푒 푐표푛푣푒푦푎푛푐푒 푠푡푟푢푐푡푢푟푒 ( ⁄푠)

퐵 = 푇표푝 푤𝑖푑푡ℎ 표푓 푡ℎ푒 푐표푛푣푒푦푎푛푐푒 푠푡푟푢푐푡푢푟푒 (푚)

3 The Hydrologic Engineering Center (HEC) in Davis, California developed the River Analysis System (RAS) to aid hydraulic engineers in channel flow analysis and floodplain determination.

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푚 푔 = 퐺푟푎푣𝑖푡푦 9.81 ( ⁄푠2)

퐴 = 푊푒푡푡푒푑 푓푙표푤 푎푟푒푎 (푚2)

Flow conditions of the Froude Number are as follow:

• Froude Number > 1 = Supercritical flow in conveyance structure.

• Froude Number < 1 = Subcritical flow in conveyance structure.

• Froude Number = 1 =Critical flow conditions in conveyance structure.

Supercritical flow conditions are typical shallow flow depths with high velocities where subcritical flow conditions are deeper flow depths with slower velocities.

10.5. RESULTS

Floodlines were simulated using the Hec-Ras Computer Program. This program comprises of a separate hydrological analysis component, data storage and reporting system. One of the steps required, is to draw in the river system schematics, by entering cross-section data.

A detailed contour survey was used to run the model.

Table 30: Hec-Ras output table

WATER FLOW TOP CHAINAGE FLOW SURFACE VELOCITY FROUDE AREA WIDTH (m) (m3/s) ELEVATION (m/s) NUMBER (m2) (m) (m) 828 69 1150.2 1.18 58.7 68.56 0.41 779 69 1149.99 1.2 57.39 62.26 0.4 728 69 1149.8 1.2 57.72 57.44 0.38 678 69 1149.61 1.27 54.53 51.38 0.39 628 69 1149.4 1.33 51.82 46.83 0.4 578 69 1149.2 1.38 50.15 42.5 0.4 528 69 1148.98 1.49 46.32 38.03 0.43 478 69 1148.59 1.98 34.92 31.54 0.6 428 69 1147.92 2.3 30.05 36.42 0.81 425 69 1147.76 2.63 26.25 37.8 1.01 415 69 1147.37 2.7 25.58 54.81 1.26 410 69 1147.16 2.57 26.87 73.96 1.36 382 69 1146.38 1.8 38.36 119.99 1.02 339 69 1145.41 1.41 48.89 111.62 0.68 305 79 1145.06 1.12 70.55 113.36 0.45 247 79 1144.53 1.56 50.65 105.87 0.72 200 79 1144.16 1.09 72.31 115.81 0.44 170 79 1144.07 0.83 95.01 135.55 0.32 150 79 1144.04 0.6 132.03 205.12 0.24

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WATER FLOW TOP CHAINAGE FLOW SURFACE VELOCITY FROUDE AREA WIDTH (m) (m3/s) ELEVATION (m/s) NUMBER (m2) (m) (m) 130 Culvert 114 79 1143.33 1.17 67.36 134 0.53 80 79 1142.64 2.15 36.76 80.14 1.01 45 79 1142.37 1.16 68.37 91.98 0.43

Lonmin-EPL-Concentrator-2 Plan: River 2 - Test 2018/01/10 Riv er 2 Hec-RAs 1152 Le gend

EG 1:100 WS 1:100 Crit 1:100 Ground

1150

1148

1146 Elevation (m) Elevation

1144

1142

1140 0 200 400 600 800 Main Channel Distance (m)

Figure 6: Long section of the stream passing the Proposed Site

10.6. INTERPRETATION

The project will be compliant with floodline and exclusion zone regulations:

• The site is outside the 1in100-year floodline (Refer to APPENDIX N).

• The site is further than 100m from the centre of the drainage line (Refer to APPENDIX O)

• The floodline levels should be shown on all relevant drawings.

• All environmental, municipal and legal requirements need to be adhered to.

• The floodlines are available in digital format (geo-referenced CAD drawings - .dwg and .dxf)

11. COMPLIANCE WITH LEGISLATION

(Refer to § 2.1) GN704 regulations

11.1. FLOODLINES: REG. 4: RESTRICTIONS ON LOCALITY)

• The facility is positioned close to a drainage line. The floodline assessment confirms that the proposed facility is outside the 1:100 yr floodlines. (Refer to: APPENDIX N: 1 IN 100-YEAR FLOODLINE BOUNDARY and

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• Floodlines for drainage lines from catchments smaller than 1 km2 have been ignored.

11.2. 100 M EXCLUSION ZONE: REG. 4: RESTRICTIONS ON LOCALITY

• The facility is positioned outside the drainage exclusion zones APPENDIX O: 100m EXCLUSION BOUNDARY

11.3. CLEAN AND DIRTY WATER SEPARATION: REG. 6: CAPACITY REQUIREMENTS OF CLEAN AND DIRTY WATER

The facility as a whole can be seen as dirty in terms of the GN704 regulations. Pollution control containment facilities are required to contain all dirty surface runoff from industrial-related activities.

11.4. DRAINAGE: REG 7: PROTECTION OF WATER RESOURCES

• The surface area of the site is 3,2 ha. Runoff is from a bunded paved terrace which is contained in a concrete lined PCD.

• Runoff in the drainage line passing the site is not affected by the construction of the plant.

11.5. ROADS: REG 7: PROTECTION OF WATER RESOURCES.

High volumes of heavy vehicles will be using the gravel road crossing Culvert C20-C21 (Refer to APPENDIX P: CULVERT LAYOUT). In order to contain silt generated during construction. The culvert crossing can be upgraded to include a silt trap which can be removed post construction. The silt trap needs to be monitored and cleaned during the construction phase and removed during the decommissioning phase. (APPENDIX T: TYPICAL DESIGN OF CULVERT CROSSING

11.6. REUSE OF WATER (REGULATION 7: PROTECTION OF WATER RESOURCES)

All the stormwater from the site. will be reused. No discharge is allowed.

12. STORMWATER MANAGEMENT PLAN: INFRASTRUCTURE REQUIREMENTS

The construction will take place on bunded concreted terraces. All dirty runoff will report to a pollution control dam where it will be contained for reuse.

Runoff rates of clean water will not be affected by the project and therefore no provision needs to be made

12.1. POLLUTION CONTROL DAM

The PCD has been sized according to legislation (Refer to §2).

Refer to APPENDIX Q to APPENDIX S

The pollution control dam (PCD) design capacity will be a minimum of 7 500 m3 at FSL. The normal operating level (NOL) of the PCD is assumed to be 2150 m34. The dam must however be operated as empty as possible and should not be used to store additional stormwater runoff, above the (NOL), for later use.

4 Glencor – P. Magee (9 Jan 2018)

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The required storage volume is based on the stormwater runoff associated with the 1:50-year storm event, risk of a repeated storm and a volume for the process water required for the plant operations.

A PCD measuring 38 x 99 x 3m deep with 1:3 inners side slopes will have a full supply storage (at spillway invert) of approximately 7 637m3. This is sufficient to comply with the requirements of GN704 as follows:

• The 50-year storm volume (5 350 mᵌ) plus mean operating level (2 150mᵌ) equals 7 500 m3.

12.2. PUMPSTATION

A pump station will be constructed at the PCD with sufficient pumping capacity to reduce the PCD level to the NOL within 24 hours. to receive a subsequent 50-year storm volume. The pump station will be constructed on top of the PCD embankment with vertical spindle pumps. Two pumps will be installed to ensure backup capacity. A float switch will be installed to activate the pump should the water level rise above the NOL. Due to the design of the pumps, no pump house building will be constructed. All pipe work at the pump station will be of hot dip galvanized and the pumps will be installed on top of reinforced concrete footing.

The proposed plant will require make up water at a rate of 228m3/hr. The 1:50-year storm volume is 5 350m3 as described above. The PCD level can thus be lowered to the NOL within 24hours should a 1:50-year storm occur at a rate of 228m3/hr.

12.3. SPILLWAY SIZING

The spillway on the pollution control dam will need to cater for storm water generated from the dirty upstream catchment, plus direct rainfall on the dam as shown below in Table 31: Spillway sizing.

Table 31: Spillway sizing

DAM 1:50-YEAR 1:100-YEAR SPILLWAY 1:50-YEAR 1:100-YEAR FLOOD PEAK FLOOD PEAK WIDTH FLOW DEPTH FLOW DEPTH m3/s m3/s m m m PCD 2.01 2.29 m3/s 38 m 0.099 m 0.106 m

12.4. BUNDING AND ACCESS RAMPS

In order to contain all runoff generated on the footprint of the facility, a reinforced concrete bund wall will be constructed around the paved site.

Access will be obtained by crossing the bund over an access ramp.

12.5. CULVERT – SILT TRAP

Culvert C20-C21 needs to be upgraded to handle the expected heavy vehicle traffic and silt load generated on the gravel road giving access to the construction site.

13. MANAGEMENT AND MITIGATION

13.1.1. CONSTRUCTION PHASE REQUIREMENTS OF THE PLANT:

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• In order to limit erosion, provide permanent water management structures in vulnerable areas where erosion could occur or spills need to be contained;

• Bury pipes and cables at a minimum depth of 500 mm below natural ground level. This will negate the need to remove them at closure;

• In order to prevent the transportation of silt to the drainage lines and low-lying areas, construct silt traps in the main drainage line at Culvert C20-C21;

• Limit the movement of people to construction areas to prevent unnecessary trampling of undisturbed areas. Destruction of vegetation results in exposed soils, which are prone to erosion;

• Prevent or minimise contamination of the site due to spillages of oil, grease, rubber and diesel from vehicles and contaminated servicing areas. Construct hydrocarbon management facilities at point of source and implement management measures to ensure that spills are contained and cleaned and drip trays are used if no paved and bunded area is available;

• Prevent contamination of the surface water system:

o Prevent incorrect waste management practices by ensuring that proper waste management processes and facilities are implemented at all waste streams.

o Control contaminated water runoff from fabrication, batch plant and laydown areas.

o Ensure that working areas are cleaned daily and that all potential sources of pollution are removed and contained as soon as possible via workshop and waste management practices.

• Treat and recycle wash water to prevent water wastage and the discharge of dirty water.

• Prohibit washing of concrete mixer trucks or other vehicles on site. Equip all wash bays to deal with silt and hydrocarbon waste.

• Contain construction water for reuse where possible.

13.1.2. OPERATIONAL PHASE REQUIREMENTS OF THE PLANT:

• In order to prevent the transportation of silt to the drainage lines and low-lying areas, maintain silt trap at the culvert crossing

• Limit the movement of people to paved areas to prevent unnecessary trampling of undisturbed areas. Destruction of vegetation results in exposed soils, which are prone to erosion.

• Prevent or minimise contamination of the site due to spillages of oil, grease, rubber and diesel from vehicles and contaminated serving areas. Construct hydrocarbon management facilities at point of source and implement management measures to ensure that spills are contained and cleaned and that and drip trays are used if no paved and bunded area is available.

• Prevent contamination of the surface water system: o Prevent incorrect waste management practices by ensuring that proper waste management processes and facilities are implemented at all waste streams. o Ensure that the working areas are cleaned daily and that all potential sources of pollution are removed and contained as soon as possible via workshop and waste management practices.

• Recycle wash/domestic water to prevent water wastage. Discharge into the PCD.

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• Prohibit random washing or maintenance of vehicles on site except within the allocated wash bays. Service the facilities regularly by removing silt and hydrocarbon waste.

13.1.3. CLOSURE PHASE REQUIREMENTS OF THE PLANT (ACTIVE DECOMMISSIONING):

• In order to limit erosion, provide permanent water management structures in vulnerable areas where erosion could occur or spills need to be contained.

• In order to prevent the transportation of silt to the drainage lines and low-lying areas, construct silt traps and spreading structures in the main drainage line running from or past the site.

• Limit the movement of people to operational areas during decommissioning to prevent unnecessary trampling of undisturbed areas. Destruction of vegetation results in exposed soils, which are prone to erosion.

• Prevent or minimise contamination of the site due to spillages of oil, grease, rubber and diesel from vehicles and contaminated serving areas. Construct hydrocarbon management facilities at point of source and implement management measures to ensure that spills are contained and cleaned and that drip trays are used if no paved and bunded area is available.

• Prevent contamination of the surface water system: o Prevent incorrect waste management practices by ensuring that proper waste management processes and facilities are implemented at all waste streams. o Control contaminated water runoff from fabrication and laydown areas. o Ensure that the working areas are cleaned daily and that all potential sources of pollution are removed and contained as soon as possible via workshop and waste management practices.

• Treat and recycle wash water to prevent water wastage and the discharge of dirty water.

• Prohibit washing of vehicles on site once wash bays have been removed.

• Implement a well-designed decommissioning plan to ensure that no waste remains on site for extended periods and that waste is disposed of in the correct manner.

• Implement well-designed rehabilitation plans: o Remove the culvert crossing. o Restore natural drainage patterns as soon as surface infrastructure is removed. o Bury all pipelines deeper than 500 mm during the construction phase, which makes removal unnecessary at closure.

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14. IMPACT ASSESSMENT

14.1. IMPACT ASSESSMENT METHODOLOGY

Evaluation Rating scale and description/criteria component

10 – Very high: Bio-physical and/or social functions and/or processes might be severely altered. MAGNITUDE OF 8 – High: Bio-physical and/or social functions and/or processes might be considerably altered. NEGATIVE IMPACT (at the 6 – Medium: Bio-physical and/or social functions and/or processes might be notably altered. indicated spatial 4 – Low: Bio-physical and/or social functions and/or processes might be slightly altered. scale) 2 – Very low: Bio-physical and/or social functions and/or processes might be negligibly altered. 0 – Zero: Bio-physical and/or social functions and/or processes will remain unaltered. 10 – Very high (positive): Bio-physical and/or social functions and/or processes might be substantially enhanced. MAGNITUDE OF 8 – High (positive): Bio-physical and/or social functions and/or processes might be considerably enhanced. POSITIVE IMPACT (at the indicated 6 – Medium (positive): Bio-physical and/or social functions and/or processes might be notably enhanced. spatial scale) 4 – Low (positive): Bio-physical and/or social functions and/or processes might be slightly enhanced. 2 – Very low (positive): Bio-physical and/or social functions and/or processes might be negligibly enhanced. 0 – Zero (positive): Bio-physical and/or social functions and/or processes will remain unaltered. 5 – Permanent 4 – Long term: Impact ceases after operational phase/life of the activity – >60 years. DURATION 3 – Medium term: Impact might occur during the operational phase/life of the activity – 60 years. 2 – Short term: Impact might occur during the construction phase – <3 years. 1 – Immediate 5 – International: Beyond national boundaries. EXTENT 4 – National: Beyond provincial boundaries and within national boundaries. (or spatial 3 – Regional: Beyond 5 km of the proposed development and within provincial boundaries. scale/influence of 2 – Local: Within 5 km of the proposed development. impact) 1 – Site-specific: On site or within 100 m of the site boundary. 0 – None 5 – Definite loss of irreplaceable resources. 4 – High potential for loss of irreplaceable resources. IRREPLACEABLE 3 – Moderate potential for loss of irreplaceable resources. loss of resources 2 – Low potential for loss of irreplaceable resources. 1 – Very low potential for loss of irreplaceable resources. 0 – None 5 – Impact cannot be reversed. 4 – Low potential that impact might be reversed. REVERSIBILITY of 3 – Moderate potential that impact might be reversed. impact 2 – High potential that impact might be reversed. 1 – Impact will be reversible. 0 – No impact. 5 – Definite: >95% chance of the potential impact occurring. PROBABILITY (of 4 – High probability: 75–95% chance of the potential impact occurring. occurrence) 3 – Medium probability: 25–75% chance of the potential impact occurring 2 – Low probability: 5–25% chance of the potential impact occurring. 1 – Improbable: <5% chance of the potential impact occurring. Evaluation Component Rating Scale and Description/criteria

High: The activity is one of several similar past, present or future activities in the same geographical area, and might contribute to a very significant combined impact on the natural, cultural and/or socio-economic resources of local, regional or national concern. CUMULATIVE Medium: The activity is one of a few similar past, present or future activities in the same geographical area, impacts and might have a combined impact of moderate significance on the natural, cultural and/or socio-economic resources of local, regional or national concern. Low: The activity is localised and might have a negligible cumulative impact. None: No cumulative impact on the environment.

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Once the Environmental Risk Ratings have been evaluated for each potential environmental impact, the Significance Score of each potential environmental impact is calculated by using the following formula:

• SS (Significance Score) = (magnitude + duration + extent + irreplaceable + reversibility) x probability.

The maximum Significance Score value is 150.

The Significance Score is then used to rate the Environmental Significance of each potential environmental impact as per Table 8.2 below. The Environmental Significance rating process is completed for all identified potential environmental impacts both before and after implementation of the recommended mitigation measures.

Table 32: Table indicating the significance criteria

Significance Environmental Description/criteria score significance

Very high (VH) An impact of very high significance will mean that the project cannot proceed, and 125–150 that impacts are irreversible, regardless of available mitigation options.

High (H) An impact of high significance which could influence a decision about whether or not 100–124 to proceed with the proposed project, regardless of available mitigation options.

Medium-high If left unmanaged, an impact of medium-high significance could influence a decision 75–99 (MH) about whether or not to proceed with a proposed project. Mitigation options should be relooked. Medium (M) If left unmanaged, an impact of moderate significance could influence a decision 40–74 about whether or not to proceed with a proposed project.

Low (L) An impact of low is likely to contribute to positive decisions about whether or not to <40 proceed with the project. It will have little real effect and is unlikely to have an influence on project design or alternative motivation.

Positive impact A positive impact is likely to result in a positive consequence/effect, and is likely to + (+) contribute to positive decisions about whether or not to proceed with the project.

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Table 33: Impact assessment – Construction phase

(PRINT A3)

ENVIRONMENTAL SIGNIFICANCE ENVIRONMENTAL SIGNIFICANCE POTENTIAL ENVIRONMENTAL RECOMMENDED MITIGATION MEASURES/ ACTIVITY BEFORE MITIGATION Cumulative Status AFTER MITIGATION IMPACT REMARKS M D S I R P TOTAL SP M D S I R P TOTAL SP Hydrology Loss of topsoil and agricultural potential due to uncontrolled surface • Provide temporary w ater management structures at vulnerable Loss of soil from the site 8 4 2 3 4 3 63 M LOW N 4 2 1 2 2 2 22 L runoff (e.g. storm events, spillages) areas during construction Siltation due to the transportation of soil during increased w ater Siltation of surface w ater features 8 2 2 3 3 4 72 M LOW N • Construct silt trap in the main drainage lines running from the site 4 2 1 2 2 2 22 L flow (e.g. storm events) on disturbed soils A percentage of runoff w ater is contained on site during this phase Reduction in catchment yield 4 4 3 2 3 4 64 M LOW N • No mitigation possible 4 4 3 2 3 4 64 M affecting the catchment yield • Hydrocarbon management facilities to be constructed at point of Surface w ater contamination: Contamination to surface w ater systems due to spillages of oil, source 6 3 2 3 4 4 72 M MED N 4 4 2 2 3 2 30 L Hydrocarbons grease, rubber and diesel from vehicles and contaminated areas • Management measures to ensure spills are contained, cleaned up and drip trays are used if no paved and bunded area is available

Surface w ater contamination: Contamination to surface w ater systems due to incorrect w aste • Ensure proper w aste management processes and facilities are 6 3 2 3 2 4 64 M MED N 4 2 2 2 1 2 22 L Domestic w aste and littering management practices implemented to ensure all w aste streams are properly managed • Workshop and w aste management practises must ensure the w orking areas are clean Surface w ater contamination: Contamination to surface w ater systems due to contaminated w ater 8 4 3 3 3 4 84 MH MED N • All potential sources of pollution are removed and contained as 6 3 2 2 3 2 32 L Industrial w aste runoff from fabricated areas, batch plant and laydow n areas soon as possible • Wash w ater must be recycled • Ensure suffient and accessable facilities are available Surface w ater contamination: Contamination to surface w ater systems due to inadequate ablution 4 2 3 3 3 3 45 M LOW N • Proper maintenance of temporary ablution facilities and emergency 4 2 2 2 3 2 26 L Sew age facilities and maintenance plans should be in place • No w ashing of concrete mixer trucks on site Surface w ater contamination: Contamination to surface w ater systems due to on-site vehicle 6 2 2 2 2 3 42 M MED N • All w ash bays must be equiped to deal w ith silt and hydrocarbon 2 2 1 1 2 2 16 L Wash w ater w ashing (e.g. concrete / mud) w aste • Ensure w ater management structures are constructed in a manner Preferential flow paths forming due to disturbances, temporary Change of flow regime from site 8 4 2 4 3 4 84 MH LOW N as to allow as much as possible natural overland flow to pass 4 2 1 3 3 3 39 L w ater pipes on surface (w hich are subject to damage) and roads through the disturbed areas Alteration to local topography Changes to topography due to bulk excavations and profiling 6 3 1 2 2 5 70 M LOW N • Landscape affected areas to blend w ith the natural topography 4 3 1 2 2 3 36 L Additional surface w ater • Stringent w ater saving measures should be implemented Additional w ater use 8 3 3 4 4 4 88 MH LOW N 6 3 3 3 3 3 54 M consumption • Water to be contained for re-use w here possible

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Table 34: Impact assessment – Operational phase

(PRINT A3)

ENVIRONMENTAL SIGNIFICANCE ENVIRONMENTAL SIGNIFICANCE RECOMMENDED MITIGATION MEASURES/ POTENTIAL ENVIRONMENTAL IMPACT ACTIVITY BEFORE MITIGATION Cumulative Status AFTER MITIGATION REMARKS M D S I R P TOTAL SP M D S I R P TOTAL SP Hydrology • Provide permanent w ater management structures at vulnerable Loss of topsoil and agricultural potential through erosion due areas Loss of soil from the site 2 3 1 2 3 3 33 L Low N 2 3 1 1 2 2 18 L uncontrolled surface runoff (e.g. storm events, spillages) • Limit the movement of people to the paved areas • Install concrete surfaces Siltation due to the transportation of soil during increased w ater Siltation of surface w ater features 2 3 1 2 2 3 30 L Low N • Maintain silt traps in the main drainage lines running from the site 2 3 1 1 2 2 18 L flow (e.g. storm events) on disturbed soils A percentage of runoff w ater is contained on site during this phase Reduction in catchment yield 4 4 3 2 3 4 64 M Low N • No mitigation possible 4 4 3 2 3 4 64 M affecting catchment yield • Hydrocarbon management facilities to be constructed at point of Contamination to surface w ater systems due to spillages of oil, source Surface w ater contamination: Hydrocarbons 4 3 2 3 4 3 48 M Low N 2 3 2 1 4 3 36 L grease, rubber and diesel from vehicles and contaminated areas • Vehicles to be serviced regularly • Clean-up of parking areas to occur once a day Surface w ater contamination: Domestic w aste and Contamination to surface w ater systems due to incorrect w aste • Ensure proper w aste management processes and facilities are 4 3 1 2 2 4 48 M Low N 2 3 1 2 2 3 30 L littering management practices implemented to ensure all w aste streams are properly managed Contamination to surface w ater systems due to inadequate ablution • Ensure suffient and accessable facilities are available Surface w ater contamination: Sew age 6 3 2 2 3 3 48 M Low N 2 3 1 2 3 2 22 L facilities and maintenance • Proper maintenance and emergency plans should be in place • Ensure w ater management structures are constructed in a manner Preferential flow paths forming due to disturbances, temporary Change of flow regime from site 4 3 2 3 3 3 45 M low N as to allow as much as possible natural overland flow to pass 2 3 2 2 3 3 36 L w ater pipes on surface (w hich are subject to damage) and roads through the disturbed areas • Stringent w ater saving measures should be implemented Additional surface w ater consumption Additional w ater use 8 3 3 2 2 4 72 M Medium N 6 3 2 2 2 3 45 M • Water to be contained for re-use w here possible

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Table 35: Impact assessment – Decommissioning and closure phase

(PRINT A3)

ENVIRONMENTAL SIGNIFICANCE ENVIRONMENTAL SIGNIFICANCE POTENTIAL ENVIRONMENTAL RECOMMENDED MITIGATION MEASURES/ ACTIVITY BEFORE MITIGATION Cumalative Status AFTER MITIGATION IMPACT REMARKS M D S I R P TOTAL SP M D S I R P TOTAL SP Hydrology • Provide permanent w ater management structures at vulnerable Loss of soil from the site (silt Loss of topsoil and agricultural potential due to uncontrolled surface 4 2 1 2 2 3 33 L Low N areas 2 2 1 2 2 3 27 L deposition) runoff (e.g. storm events, spillages) from freshly disturbed soils • Limit the movement of people to the paved areas A percentage of runoff w ater is contained on site during this phase Reduction in catchment yield 4 2 2 3 2 3 39 L Low N • Maintain silt traps in the main drainage lines running from the site 2 2 1 2 2 3 27 L affecting the catchment yield Surface w ater contamination: Contamination to surface w ater system due to spillages of oil, • Management measures to ensure spills are contained and cleaned 4 2 2 3 3 4 56 M Medium N 4 2 1 2 2 3 33 L Hydrocarbons grease, rubber and diesel from vehicles up and drip trays are used Surface w ater contamination: Contamination to surface w ater system due to incorrecy w aste • Ensure proper w aste management processes and facilities are 4 2 1 2 2 3 33 L Low N 2 2 1 2 2 2 18 L Domestic w aste and littering management practicesduring the ramp dow n phase implemented to ensure all w aste streams are properly managed Contamination to surface w ater systems due to spillages from / to Surface w ater contamination: • The w ater management structures should be the last to be w ater treatment areas (e.g. w ater purification plant and sew age 6 2 3 2 3 3 48 M Low N 6 2 3 2 2 2 30 L Sew age removed plant). High risk periods are during the removal of infrastructure Surface w ater contamination: Contamination to surface w ater systems due to demolition and • Implementation of a w ell planned decommissioning plan w ould Concrete, steel and other industrial removal of infrastructure (rebar and concrete structures and 6 2 2 2 2 3 42 M Low N ensure no w aste remains on site for extended periods of time and is 4 2 2 2 2 3 36 L w aste bulding rubble) disposed of in the correct manner

Rehabilitation plans must be w ell designed to allow for the follow ing: • Restoration of natural flow patterns and must be implemented as Preferential flow paths forming due to reshaping of rehabilitated Change of flow regime from site 6 2 1 2 2 3 39 L Low N soon as surface infrastructure is removed 4 2 1 2 2 3 33 L areas • All pipelines must be buried deeper than 500mm during the construction phase making removal unnecessary at closure

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15. REFERENCES

Department of Water Affairs and Forestry; Directorate: Resource Protection and Waste. (June 2006). Best Practice Guideline G1: Storm Water Management.

McCarthy, P. a. (2005). The story of earth and life: A Southern African perspective on a billion year journey. Cape Town: Struik nature.

Mucina and Rutherford, M. (2006). The vegetation of South Africa, Lesotho and Swaziland. : SANBI.

Van Oudthoorn, F. (2012). Guide to grasses of southern africa. Pretoria: Briz publications.

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APPENDIX A: QUATERNARY CATCHMENTS

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APPENDIX B: DOLOMITIC AREAS

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APPENDIX C: RAINFALL AND STREAM FLOW STATIONS

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APPENDIX D: VEGETATION

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APPENDIX E: GENERAL ARRANGEMENT

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APPENDIX F: SRK STORMWATER MANAGEMENT PLAN

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APPENDIX G: EPC PLANT TEST PITS

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APPENDIX H: EPL PLANT TEST PITS

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APPENDIX I: PRAXOSS CC STORMWATER MANAGEMENT PLAN FOR EPC PLANT

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APPENDIX J: PRAXOSS CC STORMWATER MANAGEMENT PLAN FOR EPL PLANT

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APPENDIX K: CONTRIBUTING CLEAN CATCHMENTS

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APPENDIX L: CONTRIBUTING DIRTY CATCHMENTS

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APPENDIX M: PROPOSED SITE LAYOUT

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APPENDIX N: 1 IN 100-YEAR FLOODLINE BOUNDARY

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APPENDIX O: 100m EXCLUSION BOUNDARY

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APPENDIX P: CULVERT LAYOUT

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APPENDIX Q: DETAIL SITE LAYOUT

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APPENDIX R: PCD LAYOUT

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APPENDIX S: TYPICAL DETAIL DRAWINGS OF PROPOSED INFRASTRUCTURE

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APPENDIX T: TYPICAL DESIGN OF CULVERT CROSSING

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