GEOTECHNICAL ASSESSMENT

Public
REPORT

Dalmanutha Wind Energy Facility

Geotechnical Desktop Assessment
WSP Africa

Submitted to:
Ashlea Strong
Knightsbridge
33 Sloane Street
Bryanston
2191

Submitted by:
WSP Group Africa (Pty) Ltd.
Building 1, Maxwell Office Park, Magwa Crescent West, Waterfall City, Midrand, 1685, South Africa
P.O. Box 6001, Halfway House, 1685

+27 11 254 4800

21500715-352637-3_Rev2

18 May 2023
18 May 2023 21500715-352637-3_Rev2

Distribution List
1 x Electronic Copy to WSP Africa

1 x Electronic Copy to WSP Golder SharePoint Project File

1 x Electronic Copy to WSP Golder Library

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Record of Issue

Company Client Contact Version Date Issued Method of Delivery

WSP Africa Ashlea Strong Rev0 2 June 2022 Electronic

WSP Africa Ashlea Strong Rev1 28 April 2023 Electronic

WSP Africa Ashlea Strong Rev2 19 May 2023 Electronic

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Table of Contents
1.0 INTRODUCTION ......................................................................................................................................... 1

1.1 Project Description ........................................................................................................................... 1

1.2 Scope of Work .................................................................................................................................. 4

1.3 Specialist Credentials ....................................................................................................................... 4

2.0 STUDY AREA INFORMATION ................................................................................................................... 4

2.1 Site Location and Physical Description ............................................................................................ 4

2.2 Drainage and Topography ............................................................................................................... 5

3.0 GEOLOGY ................................................................................................................................................... 7

4.0 RESULTS OF THE DESKTOP STUDY ...................................................................................................... 9

4.1 Engineering Geology of Encountered Formations ......................................................................... 11

5.0 GEOTECHNICAL EVALUATION ............................................................................................................. 15

5.1 Excavatibility .................................................................................................................................. 15

5.2 Foundations for Wind Turbines ...................................................................................................... 17

6.0 GEOTECHNICAL IMPACT ASSESSMENT ............................................................................................. 18

7.0 FURTHER GEOTECHNICAL RECOMMENDATIONS ............................................................................. 18

8.0 CONCLUSIONS ........................................................................................................................................ 19

9.0 ASSUMPTIONS AND LIMITATIONS ....................................................................................................... 19

10.0 REFERENCES .......................................................................................................................................... 19

TABLES
Table 1: Key technical details of the Dalmanutha WEF ....................................................................................... 1
Table 2: Lithostratigraphy of the area ................................................................................................................... 9
Table 3: Geological Formations Underlying the Alternative 1 Turbines and associated infrastructure ............. 11
Table 4: Geological Formations Underlying the Alternative 2 Turbines and Associated Infrastructure ............. 11
Table 5: Excavation Classes .............................................................................................................................. 16
Table 6: Excavatibility ......................................................................................................................................... 17

FIGURES
Figure 1: Locality of the Project Site ..................................................................................................................... 5
Figure 2: Elevation Map of the Project Site (Alternative 1 and Alternative 2) ...................................................... 6

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Figure 3: Slope Map of the Project Site (Alternative 1 and Alternative 2) ............................................................ 6
Figure 4: Proposed WEF Area Characterized by Hilly Terrain (Photos Taken from WTG7 Facing WTG63) ...... 7
Figure 5: Geology Map of Alternative Project Site ............................................................................................... 8
Figure 6: Geology Map of Alternative 2 Project Site ............................................................................................ 8
Figure 7: Seismic Hazard Map of South Africa .................................................................................................. 10
Figure 8: Position of Turbines in the Dalmanutha WEF Alternative 1 and Alternative 2 .................................... 12
Figure 10: Small Vryheid Shale Borrow Pit Observed on Site Close to WTG37 on the Northern Portion ......... 12
Figure 11: Diabase Hill with Boulders, Located Close to WTG49, Side Profile (Left) and Top (Right) .............. 13
Figure 12: Quartzite on Surface, Photo Taken Facing WTG45 (Left) and Facing WTG16 (Right) .................... 14
Figure 13: Quartzite on Surface ......................................................................................................................... 14
Figure 14: Silverton Shale .................................................................................................................................. 15

APPENDICES
APPENDIX A
Specialist CVs
APPENDIX B
Geotechnical Impact Assessment
APPENDIX C
Document Limitations

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1.0 INTRODUCTION
WSP Golder Pty Ltd (Golder) was appointed by WSP Africa (WSP) to provide a geotechnical desktop
assessment for the proposed Dalmanutha Wind Energy Facility (WEF). WSP was appointed by Dalmanutha
Wind (Pty) Ltd to carry out an Environmental Impact Assessment (EIA) for the WEF development. The purpose
of this desktop study is to provide preliminary geotechnical information regarding the feasibility for the proposed
project and to indicate potential geotechnical constraints.

P Africa

This report presents the results of the desktop study.

1.1 Project Description

Two alternatives are proposed for the Dalmanutha WEF. Alternative 1 is a full wind energy facility, with a
capacity of up to 300MW, comprising up to 70 wind turbines; Alternative 2 is a hybrid facility, with a capacity of
up to 300MW, comprising 44 turbines and two solar fields. The Dalmanutha WEF alternatives will comprise the
following:
Table 1: Key technical details of the Dalmanutha WEF

Component Description

Development Dalmanutha Wind Energy Facility Alternative 1

Berg-en-Dal 378 JT (Portions 1 and 9) Vogelstruispoort 384 JT (Portion 5 and 7)

Waaikraal 385 JT (Portions 6, 7, 8, 10, Leeuwkloof 403 JT (Portions 3 and 4)

12,13 and 24)
Affected farms
Leeuwkloof 404 JT (Portions 1 and 2) Geluk 405 JT (Portion 3)

Camelia 467 JT (Portion 0) Welgevonden 412 JT (Portion 1

Extent approximately 9 197 ha.

approximately 400ha (subject to finalisation based on technical and environmental
Buildable area
requirements)
Capacity Up to 300MW

Up to 70 turbines, each with a foundation of approximately 25m2 in diameter (500m2 area

and requiring ~2 500m3 concrete each) and approximately 3m depth

Turbine hub height of up to 200m

Wind turbines
Rotor diameter up to 200m

Permanent hard standing area for each wind turbine (approximately 1ha).

IPP portion onsite substation of up to 4ha. The substation will consist of a high voltage
On-site IPP
substation yard to allow for multiple up to 132kV feeder bays and transformers, control
substation and
Battery Energy building, telecommunication infrastructure, access road, etc.
Storage
System (BESS) The Battery Energy Storage System (BESS) storage capacity will be up to 300MW/1200
megawatt-hour (MWh) with up to four hours of storage. It is proposed that Lithium Battery

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Component Description

Technologies, such as Lithium Iron Phosphate, Lithium Nickel Manganese Cobalt oxides or
Vanadium Redox flow technologies will be considered as the preferred battery technology;
however, the specific technology will only be determined following Engineering,
Procurement, and Construction (EPC) procurement. The main components of the BESS
include the batteries, power conversion system and transformer which will all be stored in
various rows of containers.

Operations and maintenance (O&M) building infrastructure will be required to support the
functioning of the WEF and for services required by operations and maintenance staff. The O&M
building infrastructure will be near the onsite substation and will include:

Operations building of approximately 200m 2

Operations and
Maintenance Workshop and stores area of approximately 150m 2
(O&M) building
footprint Stores area of approximately 150m2

Refuse area for temporary waste and septic/conservancy tanks with portable toilets to
service ablution facilities.

The total combined area of the buildings will not exceed 5 000m 2.

Temporary laydown or staging area -Typical area 220m x 100m = 22000m².

Laydown area could increase to 30000m² for concrete towers, should they be required.

Sewage: septic and/or conservancy tanks and portable toilets.

Temporary cement batching plant, wind tower factory & yard of approximately 7ha,
Construction comprising amongst others, a concrete storage area, batching plant, electrical infrastructure
Camp Laydown and substation, generators and fuel stores, gantries and loading facilities, offices, material
stores (rebar, concrete, aggregate and associated materials), mess rooms, workshops,
laydown and storage areas, sewage and toilet facilities, offices and boardrooms, labour
mess and changerooms, mixers, moulds and casting areas, water and settling tanks,
pumps, silos and hoppers, a laboratory, parking areas, internal and access roads - Gravel
and sand will be stored in separate heaps whilst the cement will be contained in a silo. The
maximum height of the silo will be 20m

The Project site can be accessed easily via either the tarred R33 or the N4 national road
which run along the northern and western boundaries of the site.

There is an existing road that goes through the land parcels to allow for direct access to the
project development area.
Access roads
Internal and access roads with a width of between 8m and 10m, which can be increased to
approximately 12m on bends. The roads will be positioned within a 20m wide corridor to
accommodate cable trenches, stormwater channels and bypass /circles of up to 20m during
construction. Length of the internal roads will be approximately 60km.

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Component Description

Cables up to and including 33kV that run underground, except where a technical assessment
suggest that overhead lines are required, within the facility connecting the turbines to the onsite
Cables substation.
Over the fence 132kV cable to connect the onsite IPP substation to the Common Collector
Switching Station.

Fencing of up to 4m high around Lightning protection Telecommunication

the construction camp and infrastructure
lighting

Stormwater channels Water pipelines Offices

Associated Operational control centre Operation and Ablution facilities

infrastructure Maintenance Area /
Warehouse/workshop

A gatehouse Control centre, offices, Security building

warehouses

Substation building

Development Dalmanutha Wind Energy Facility Alternative 2: Hybrid Energy Facility

Extent Approximately 9 197ha

Buildable area Approximately 400ha

Up to 44 turbines, each with a foundation of approximately 25m 2 in diameter (500m2 area

and requiring ~2 500m3 concrete each) and approximately 3m depth

Turbine hub height of up to 200m

Wind turbines
Rotor diameter up to 200m

Permanent hard standing area for each wind turbine (approximately 1ha per turbine)

Solar PV array comprising PV modules (solar panels), which convert the solar radiation into
direct current (DC)

PV panels will be up to a height of 6m (when the panel is horizontal) and will be mounted
on fixed tilt, single axis tracking or dual axis tracking mounting structures. Monofacial or
Solar Fields bifacial Solar PV Modules are both considered

Footprint: ~160 ha

Inverters, transformers and other required associated electrical infrastructure and

components

Associated The associated infrastructure is the same as for Alternative 1

infrastructure

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1.2 Scope of Work

The geotechnical desktop study scope of work includes the following:

A review of available published and unpublished information including, but not limited to, geological data,
geological maps, topographical maps and aerial images of the study area

A site reconnaissance to observe general site characteristics

An assessment of relevant geotechnical and geological fatal flaws within the study area

Recommendations regarding requirements for subsequent detailed geotechnical investigations

1.3 Specialist Credentials

The geotechnical desktop study was undertaken by an experienced professionally registered engineering
geologist and the work was overseen by a professionally registered senior geotechnical engineer.

Khuthadzo Bulala is an engineering geologist with a Bachelor of Science Honors Degree from the University
of Limpopo. She is registered as a Professional Scientist (Pr.Sci.Nat 116482). Khuthadzo has seven years of
experience in engineering geology, geotechnical engineering, environmental geology, and soil surveys. She
has extensive experience in conducting renewable energy geotechnical assessments and detailed geotechnical
investigations.

The desktop studies will be reviewed and authorized by Heather Davis. Heather is a qualified Professional
Engineer (Pr.Eng 960229) with 40 years of experience. She obtained a BSc Honours degree in Engineering
Geology and Geotechnics from the University of Portsmouth (UK) in 1982. A post graduate diploma was
obtained from the University of the Witwatersrand in 1993 which focused on geotechnical engineering and rock
mechanics. She is currently the geotechnical team lead at WSP Golder. Her responsibilities include providing
geotechnical inputs to various projects, quality assurance on all geotechnical work and provision of reports. She
has accumulated extensive experience in Sub Saharan Africa which has included work on the Medupi and
Kusile Power Plants and on renewable projects such as the Sere Wind Farm, for Eskom, in the Northern Cape.

Heather Davis are included in APPENDIX A.

2.0 STUDY AREA INFORMATION

2.1 Site Location and Physical Description
The proposed Dalmanutha WEF is located approximately 7km southeast of the town of Belfast within the
Emakhazeni Local Municipality, Mpumalanga Province.

A locality plan is presented as Figure 1. The site is accessed via the N4, which is approximately 220 meters
north from the proposed development area. There is an existing gravel road that goes through the parcels of
land from north to south to allow for direct access to the project development area. The majority of the farms
are utilized for cattle and horse farming. Minor agricultural activities were also observed during the site
reconnaissance. Most of the areas is characterized by short grass and sparse trees.

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Figure 1: Locality of the Project Site

2.2 Drainage and Topography

The site lies within the Quaternary catchment X11D. This catchment receives 744mm rainfall per year and
experiences 1413mm of evaporation annually. Numerous non-perennial rivers drain in an easterly direction into
the perennial Waalkraalloop river and in a westerly and southerly direction into the perennial Klein Komati River.

Marsh/vlei features are indicated on Figure 2 to the north and south of the site.

The terrain consists of rolling hills with flat hill tops. The proposed WEF lies at an elevation of approximately
1630m in the northern section to 1888m in the southern section. Areas with a relatively high elevation are shown
in green on Figure 2. whilst areas with a relatively low elevation are shown in pink.

The majority of the WEF has a slope of between 4.4o and 10.2o. The central part of the site is generally flat with
a range in slope from 0.0o to 4.4o as shown in Figure 3. The southern portion is characterized by hills leading to
steeper slopes of between 10.2o 34.4o. However, all the turbines and the western solar field in this area are
located on the flat hill tops. The eastern solar field is located across a valley and is characterized by steep
slopes. A general view of the site is provided in Figure 4.

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Figure 2: Elevation Map of the Project Site (Alternative 1 and Alternative 2)

Figure 3: Slope Map of the Project Site (Alternative 1 and Alternative 2)

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Figure 4: Proposed WEF Area Characterized by Hilly Terrain (Photos Taken from WTG7 Facing WTG63)

3.0 GEOLOGY
According to the published 1: 250 000 geological map (Sheet 2530 Barberton), the western and northeastern
portions of the study area are underlain by the Vryheid Formation (Pv), Ecca Group, Karoo Supergroup. This
comprises quartzitic, cross-bedded sandstone, pebbly near its base, gritty sandstone and shale.

A small portion of the western boundary is underlain by the Vermont Formation (Vv) comprising fine-grained
hornfels, with sedimentary structures, near the top and base, layers of silt and sandstone and minor layers of
carbonate and calc-silicate rocks, Hornfels was not observed on site during the reconnaissance. However,
baked shale was encountered.

The central portion of the site is underlain by the Magaliesberg Formation (Vm) which comprises pure, coarse-
grained, white quartzite containing sporadic impersistent shale layers in places, upper part comprising
interlayered shale, siltstone and quartzite, and lower part shale.

The eastern portion is underlain by the Silverton Formation (Vsl) comprising greenish, fine-grained, laminated
shale and subordinate mudstone, interlayered carbonate layers rare, hornfels in places.

The Vermont, Magaliesberg and Silverton Formations form part of the Pretoria Group, Transvaal Supergroup.
These formations have been intruded by diabase (Vdi). Recent surficial deposits (Q), alluvium and scree blanket
a small section of the study area.

Excerpt of the published geological map showing the two alternative project areas are presented as Figure 5
and Figure 6 respectively.

The lithostratigraphy of the area is presented in Table 2.

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Figure 5: Geology Map of Alternative 1 Project Site

Figure 6: Geology Map of Alternative 2 Project Site

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Table 2: Lithostratigraphy of the area

Super- Group Formation Member Lithology Map
group symbol
Dolerite Vdi

Karoo Ecca Vryheid Quartzitic, cross bedded, sandstone, gritty Pv

sandstone & shale

Transvaal Pretoria Vermont Fine grained hornfels. Layers of siltstone Vv

and sandstone. Minor layers of carbonate
and calc-silicate rocks
Magaliesberg Pure, coarse-grained quartzite with some Vm
shale layers in places. Upper part
comprises interlayered shale, siltstone and
quartzite.
Silverton Lydenburg Greenish, fine grained, laminated shale and Vsl
Shale subordinate mudstone. Interlayered
carbonate layers are rare. Hornfels in
places

4.0 RESULTS OF THE DESKTOP STUDY

A site reconnaissance of the study area was conducted by Golder personnel on Monday 14th March 2022.

A summary of the key findings from the desktop study and site reconnaissance is provided below.

Climate

The climatic regime of the present and of the relatively recent times plays a fundamental role in the development
of the soil profile. The site falls within the sub-humid part of South Africa where Weinerts climatic N-value is less
than 5 which promotes chemical weathering and results in thick deeply weathered residual soils. Pedocretes,
where present, are likely to be in the form of ferricrete. However, during the site reconnaissance, surface and
subsurface rock was observed. Thicker soil profiles are anticipated in the valleys.

Undermining

Subsidence at surface in undermined areas is caused by collapse and failure of the underground mining void
relatively close to the surface (Heath and Engelbrecht, 2011). The Dalmanutha WEF site is located
approximately 8km southeast of the North Block Complex Belfast Coal Mine and approximately 10km east of
the Exxaro Belfast Mine. Both mines are operating as open cast mines and, hence, there is no undermining at
the WEF site, and no mine related subsidence is expected.

Flooding

Flooding affects flat lying areas, areas confined to drained channels and flood plains. All the turbines are located
on flat hill tops where water ponding is a possibility. Stormwater management is recommended at all flat areas
to facilitate water run-off and to alleviate the possibility of standing water at the positions of foundations.

Erosion

The topography of the site and erosion are interrelated. The slope on site, as well as the soil structure will
influence the amount of erosion. Land on steeper slopes will be more prone to erosion.

It must be noted that no significant erosion channels were encountered during the reconnaissance with the
exception of erosion gullies along the farm road cuttings.

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The proposed turbine locations and solar fields are covered with grass and sparse trees, and there is therefore
a reduced risk of erodibility problems. The possibility of erosion must be mitigated, at each turbine position, by
revegetation after construction.

Seismicity

According to the published seismic hazard map of South Africa (Kijko, et al., 2003), the probability of a seismic
event occurring is low with a value for peak ground acceleration at the site being between 0.08 and 0.12m/s as
illustrated in Figure 7.

A 10% probability exists that this value will be exceeded in a 50-year period.

Figure 7: Seismic Hazard Map of South Africa

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4.1 Engineering Geology of Encountered Formations

The turbine and solar fields positions are underlain by four different geological formations as listed in Table 3
below.

Plans indicating the layout of the proposed positions of the turbines and solar fields in Dalmanutha WEF
alternative 1 and Dalmanutha WEF alternative 2 are presented as Figure 8.

Table 3: Geological Formations Underlying the Alternative 1 Layout

Geology Turbines Associated Infrastructure

Diabase WTG59

Vryheid Formation WTG01 to WTG9 WTG30 to WTG39 On-site IPP Substation and BESS
WTG13 WTG45 WTG50 Laydown and construction camp
WTG15 to WTG18 WTG67 Batching plant and wind tower
WTG23 to WTG28 factory

Vermont Formation WTG29

Magaliesberg Formation WTG12 to WTG12 WTG63 to WTG64

WTG14 WTG68 to WTG70
WTG21 to WTG22

Silverton Formation WTG19 to WTG20 WTG51 to WTG58

WTG51 WTG60 to WTG62
WTG40 to WTG44 WTG65 to WTG66

Table 4: Geological Formations Underlying the Alternative 2 Layout

Geology Turbines Associated Infrastructure

Diabase No turbines, solar or associated structure

Vryheid Formation WTG01 to WTG7 WTG22 to WTG26 On-site IPP Substation and BESS
WTG10 to WTG11 WTG29 Laydown and construction camp 1 & 2
WTG13 to WTG16 WTG33 Batching plant and wind tower factory 1 & 2
WTG18 to WTG20 WTG43 Majority of solar 1

Vermont Formation WTG21

Magaliesberg WTG8 to WTG9 WTG27 Southern section of solar 1

Formation WTG12 WTG34
WTG17 WTG42
WTG44

Silverton Formation WTG28 Solar 2

WTG30 to WTG32
WTG35 to WTG41

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Figure 8: Position of Turbines in the Dalmanutha WEF Alternative 1 and Alternative 2

Vryheid Formation

On site, shale of the Vryheid Formation was observed in a small borrow pit situated close to WTG37. The profile
in the pit comprised a thin layer of transported and residual soil underlain by shale as illustrated in Figure 9.

Figure 9: Small Vryheid Shale Borrow Pit Observed on Site Close to WTG37 on the Northern Portion

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Vryheid shale generally weathers to a clayey residual soil which is often compressible and potentially expansive.
Expansive soils are those materials that exhibit volume change with a change in moisture content. These
moisture content
increases. Where the residual shale profile is thinly developed, it is recommended that the material should be
stripped. Where thickly developed, the structural design needs to take cognizance of the potential
expansiveness.

Some shale breaks down rapidly after exposure to the elements with micro-cracks developing as a result of
moisture loss or stress relief. Mudrocks such as shale, are generally not considered suitable for use as
construction materials. This is due to their potential expansiveness, excessive absorption of water, poor
engineering performance and lack of durability. However, some shale material is considered suitable for use as
selected layers in road construction (wearing coarse for gravel roads). However, the durability and potential
expansiveness should be ascertained beforehand.

Diabase (Dolerite)

Diabase was not observed in outcrop across the site during the site reconnaissance. A hill with diabase boulders
was observed approximately 0.35m south-west of WTG49, Figure 10. According to the published geological
map, WTG54 is underlain by diabase. According to the Google Earth image, diabase boulders may be present
in the area of WTG54.

Generally, the residual soil is relatively thickly developed above diabase rock with the profile becoming coarser
with depth. Cobbles and boulders are often present above the rock grading into gravel, sand and finally residual
clay. Cobbles and boulders of diabase, however, are often present throughout the residual profile.

Residual clay is generally compressible and potentially expansive in the range. Where a
structure straddle residual diabase and a different soil type, the structure should be moved to avoid differential
settlement or designed accordingly.

Diabase rock, cobbles, boulders, gravel and sand a generally durable and are suitable for a variety of purposes.
It is commonly quarried and used as a construction material such as for concrete aggregate and road
construction material.

Figure 10: Diabase Hill with Boulders, Located Close to WTG49, Side Profile (Left) and Top (Right)

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Magaliesberg Formation

Quartzite outcrop was observed on surface across the center of the WEF on the flat hilltop. The sides of the
slopes are characterized by quartzite boulders as shown in Figure 11 and Figure 12. The quartzite encountered
is cream white, moderately weathered, medium to coarse grained, medium hard to hard rock. Where present,
residual soils are likely to be thinly developed.

Figure 11: Quartzite on Surface, Photo Taken Facing WTG45 (Left) and Facing WTG16 (Right)

Although not observed on site, the residual soil tends to comprise loose silty sand or clayey sand with a thickness
of less than 2m. The residual quartzitic clayey/silty sand may be potentially collapsible.

Soils with a collapsible structure experience additional settlement when subjected to an inundation of some
kind. This occurs without an increase in loading and may occur many years after construction. Soil improvement,
by means of compaction with the addition of water to -1% to +2% of optimum moisture content might be required
where the residual soil is thickly developed. This is, however, not expected as rock is expected to be
encountered within the 3m excavation required for the turbine bases.

Quartzite is often quarried and used as concrete aggregate and in road pavement layers.

Figure 12: Quartzite on Surface

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Silverton Formation (Shale)

Silverton shale underlies the majority of the eastern side of the site. Shale outcrop was encountered on a road
near to WTG25 (Figure 13). The rock is light grey, moderately weathered, fine grained, thinly laminated, with
light yellow silty sand infill along the bedding planes, soft rock shale. The rock was overlain by a thin (0.30m)
layer of residual shale profiled as slightly moist, light brown to beige, soft, intact, sandy silt. A slightly moist, light
greyish brown, loose, silty sand topsoil blanketed the area.

Figure 13: Silverton Shale

The residual profile is generally thinly developed above the Silverton shale, less than 2m thick, and is expected
to comprise a clay/silt material. The residual clay is generally potentially expansive and compressible.

Areas of subsurface or surface shale are present throughout the site and give rise to restricted drainage. Where
a shallow water table is proven during the detailed investigation or the flat areas on top of the slopes, water
ponding must be prevented to avoid the oversaturation of the residual soils. Residual shale soils are
impermeable, which will lead to water ponding in and around the foundation. This can lead to differential
settlement of the foundations, hence, stormwater management in the area is imperative.

Silverton shale can be used as sub-base and even base-course material, but usually the material will require
mixing with granular material to improve the grading or blending to decrease the plasticity.

5.0 GEOTECHNICAL EVALUATION

It is anticipated that areas of outcrop, shallow rock and relatively thinly developed soil will be present across
much of the Dalmanutha site.

5.1 Excavatibility
The excavation characteristics of the soil horizons has been evaluated according to the South African Bureau
of Standards standardized excavation classification for earthworks (SABS 1200D). The definition of the
excavation classes is indicated in Table 5 and the assessment of the in-situ profile in Table 6.

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Table 5: Excavation Classes

Class of General Definition

Excavation

Soft Excavation in material which can be efficiently removed or loaded by any of the following
plant without prior ripping: -
A bulldozer with a mass of at least 22 tons (which includes the mass of the ripper, if fitted)
and an engine developing approximately 145kW at the flywheel. Or
A tractor-scraper unit with a mass of at least 28 tons and an engine developing approximately
245kW at the flywheel, pushed during loading by a bulldozer as specified for intermediate
excavation. Or
A track type front end loader with a mass of at least 22 tons and an engine developing
approximately 140kW at the flywheel

Intermediate Excavation (excluding soft excavation) in material which can be efficiently ripped by a
bulldozer with a mass of at least 35 tons when fitted with a single tine ripper and an engine
developing approximately 220kW at the flywheel.

Hard Excavation (excluding boulder excavation) in material which cannot be efficiently ripped by a
bulldozer with properties equivalent to those described for intermediate excavation. This type
of excavation generally includes excavation in material such as formations of unweathered
rock, which can be removed only after blasting.

Boulder a) Excavation in material containing in excess of 40% by volume of boulders between

Class A 0.03m3 and 20m3 in size, in a matrix of softer material or smaller boulders.
b) Excavation of fissured or fractured rock shall not be classed as boulder excavation but
as hard or intermediate excavation according to the nature of the material.

Boulder Where material contains 40% or less by volume of boulders in a matrix or soft material or
Class B smaller boulders.

The ease of excavation is a critical financial factor for any development. As evidenced during site
reconnaissance, surface and subsurface rock characterizes majority of the area.

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Table 6: Excavatibility

Material Excavation Class

Quartzite
Shale
Diabase

Transported material Soft excavation.

Diabase Soft excavation in residual clay, sand and gravel.

Boulder Class A and Boulder Class B where boulders are encountered.
Hard excavation in diabase rock

Vryheid shale and Soft excavation in residual shale and very soft to soft rock.
residual soil Intermediate to hard excavation in medium hard and harder rock

Vermont Formation Soft excavation in residual hornfels and very soft to soft rock.
Intermediate to hard excavation in medium hard and harder rock

Magaliesberg Soft excavation where residual quartzite is present.

quartzite and residual Intermediate to hard excavation from surface where outcrop is present and from a
soil shallow depth where rock is encountered.

Silverton shale and Soft excavation in residual shale and very soft to soft rock.
residual soil Intermediate to hard excavation in medium hard and harder rock

Up to a depth of 3m, all excavations should be excavated at a batter of 1:1 in soil where no water or seepage
is evident and to 1:2, or flatter, where water is encountered. Rock can be excavated at a batter of 1:0.5 or
vertically in the temporary case up to a depth of 3m.

According to the published geological map the regional dip of the shale and quartzite is approximately 8° to the
northwest. Instability is, therefore, not expected in rock slopes as the regional dip is less than the expected
shear strength parameters of the rock.

Depending on the embedment depth, blasting may be required for cable trenches. Alternatively, surface
conduits or pole mounted cables may be considered to alleviate the costs of blasting.

5.2 Foundations for Wind Turbines and Solar Pylons

Turbines

The proposed foundation bases are 25m2 in area and the concrete base is 3m deep. The structures exert a
static load. However, it is loading as a result of the high wind shear that drives the selection of founding medium.
A high strength material is required for founding to provide sufficient bearing capacity and strength

Rock is expected across much of the site at a depth of less than 3m and, therefore founding in rock is
recommended. It is recommended that test pits be excavated at each turbine position during the geotechnical
site investigation to determine the depth to rock and the strength characteristics thereof. Some rotary cored
boreholes would be required to determine the rock strength with depth in, particularly, the shales. The quartzite
is expected to be medium hard to hard from surface or from a shallow depth.

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Solar Pylons

The structures exert a static load. However, it is loading as a result of the high wind shear that drives the
selection of founding medium. A high strength material is required for founding to provide sufficient bearing
capacity and strength.

Due to the variation in the geotechnical conditions across the site, the foundation recommendations will vary
depending on the geotechnical ground conditions.

In the areas underlain by quartzite, rock is expected on surface or in depth shallower than approximately 1.50m,
and conventional founding in rock is recommended. The depth to rock in the areas underlain by mudrock (shales
and siltstones) is expected to be >3m.

Proposed foundation types recommended are driven piles (areas with boulders and shallow bedrock excluded)
and cast in-situ concrete piles (an appropriate piling method that can pierce through boulders and shallow soft
to very soft rock).

6.0 GEOTECHNICAL IMPACT ASSESSMENT

Geotechnical impacts need to be taken into account as part of the WEF development. The identified risks can
typically be mitigated by the implementation of an appropriate and effective plan. Mitigation measures must be
implemented to avoid or reduce negative impacts during the construction, operation and decommissioning
phases.

The geotechnical impact assessment applies for the two alternative WEF sites: Dalmanutha WEF and
Dalmanutha Hybrid Energy Facility. The associated infrastructure falls within the same geology and slope
characteristics and the either option is recommended for construction.

Based on the impact assessment matrix undertaken for this project, from a geotechnical perspective the impact
of the Dalmanutha WEF was found to be to high impact - The anticipated impact will have
The assessment impact assessment matrix is presented as
APPENDIX B.

The WEF application site is considered suitable for the proposed development provided that the
recommendations presented in this report are adhered too and which need to be verified by more detailed
geotechnical investigations during detailed design.

7.0 FURTHER GEOTECHNICAL RECOMMENDATIONS

A detailed intrusive site investigation is recommended to further characterize site conditions, to better
understand the key geotechnical risks characteristics in order to refine the development of the WEF. Based on
the current lack of previous geotechnical investigation data, the primary objectives of the proposed intrusive
investigation must include:

Determination of the founding conditions for all structures. The scope of the intrusive investigation should
comprise test pitting, the drilling of a representative number of boreholes and laboratory testing.

Investigation of subgrade conditions for service roads.

Investigation for materials to be used during construction.

Non-intrusive investigation techniques, such as geophysical (seismic refraction) surveys, thermal and
electrical resistivity for ground earthing requirement.

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8.0 CONCLUSIONS
Based on desktop study, the proposed Dalmanutha site is suitable for the operation of a
WEF.

negative moderate to very high impact was assessed, from a geotechnical perspective, for the pre-mitigation
situation for the Dalmanutha WEF. Post-mitigation, the assessed impact decreases significantly to

A geotechnical site investigation must be undertaken to provide detailed geotechnical information for the design
of the proposed structures and roads.

9.0 ASSUMPTIONS AND LIMITATIONS

Your attention is drawn to APPENDIX C
are intended to advise you of what your realistic expectations of this report should be, and to present you with
recommendations on how to minimize the risks associated with the groundworks for this project. The document
is not intended to reduce the level of responsibility accepted by WSP Golder, but rather to ensure that all parties
who may rely on this report are aware of the responsibilities each assumes in so doing.

10.0 REFERENCES
1: 250 000 Geological Map Series (2530 Barberton). Published by the Council of Geoscience.

Brink. A.B.A (1979). Engineering Geology of Southern Africa: The first 2000 million years of geological time.
Volume 1. Building Publications: Pretoria.

Brink. A.B.A (1983). Engineering Geology of Southern Africa: The Karoo Sequence. Volume 3. Building
Publications: Pretoria.

Heath G. and Engelbrecht J. (2011). Deformation due to Mining Activities. Council for Geoscience. Report
Number 2011-065.

Kijko, A., Graham, G., Bejaichund, M., Roblin, D., Brand, M.B.C. (2003). Probabilistic Peak Ground
Acceleration and Spectral Seismic Hazard Maps for South Africa. Council for Geoscience. Report no. 2003
0053.

South African National Standards 1200D: Earthworks, (1998).

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18 May 2023 21500715-352637-3_Rev2

Signature Page

WSP Group Africa (Pty) Ltd.

Khuthadzo Bulala (Pr. Sci. Nat) Heather Davis (Pr. Eng)

Engineering Geologist Geotechnical Team Lead

KB/HD/mk

\\corp.pbwan.net\za\central_data\projects\41100xxx\41103722 - dalmanutha wef\41 mo\rev2-client comments\dalmanutha wef\21500715-352637-3_rep_dalmanutha wef

desktop_rev2_20230517.docx

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18 May 2023 21500715-352637-3_Rev2

APPENDIX A

Specialist CVs
 Khuthadzo Bulala
Engineering Geologist

PROFESSIONAL SUMMARY

Khuthadzo Bulala, Pr.Sci.Nat. - is an engineering geologist with 6 years'

experience in geotechnical investigations. Her experience and technical skills
include:

Compilation of geotechnical investigation reports

Education Geotechnical core logging
BSc. (Honours) in Core orientation for inclines boreholes
Geological Sciences, Planning, managing, and executing in-situ testing (test-pitting,
University of Limpopo, geotechnical drilling operations, DCP testing and piezometer
South Africa, 2013 installations) for geotechnical investigations
Laboratory testing selection and liaison with laboratories
BSc. Degree in Geological
Analysis and interpretation of laboratory and in-situ test data
Sciences, University of
Geological mapping and sourcing of construction materials and
Johannesburg (Auckland
aggregates
Park Campus), South
Sourcing, testing and specification of construction materials and
Africa, 2011
aggregates
Certifications Health and safety documentation for fieldwork projects
South African Council for Project management including resource management and client liaison
Natural Professions
(SACNASP) - Pr. Sci. Nat EMPLOYMENT HISTORY
(116482)
Golder Associates Africa (Pty) Ltd Midrand, Gauteng

Engineering Geologist (Oct 2021 to Present)

Geotechnical investigations for renewable energy

Geotechnical desktop studies for railway lines
Geotechnical investigations for infrastructure

JG Afrika (Pty) Ltd Pietermaritzburg, Kwa-Zulu Natal

Junior Engineering Geologist (Sept 2016 to Sept 2021)

Geotechnical investigations (Phase-1 & 2) and report reviews for

housing development as per NHBRC requirements.
Geotechnical investigation for renewable energy projects (wind energy
facilities, solar farms, and their associated structures)
Geotechnical investigations for roads and bridge structures.
Evaluation of sites for cemetery and landfill developments or
extensions.
Geotechnical investigation for dams, pipelines, water treatment works,
and waste-water treatment works projects.
Geotechnical investigation for buildings (refurbishments, damaged,
new structures).
Material source investigation for construction projects.
Site supervision for rotary and percussion drilling projects.
Agricultural soil survey to assessment site potential.

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Lesotho Highlands Development Agency (LHDA) Polihali, Lesotho

Engineering Geology Intern (March 2016 to August 2016)

Geotechnical investigation for the Polihali Dam investigation based

on site full time

RELEVANT EXPERIENCE

Geotechnical Investigation for the ArcelorMittal Mine Extensions

Tokadeh, Liberia
Geotechnical report writing for the ArcelorMittal facilities; Tokadeh pit, Tokadeh
infrastructure, Gangra Pit, Water Storage Dam, Tailings Management Facility,
and Bucanan Port.
Geotechnical Investigation for Polihali Dam, the Diversion Tunnel and the
Transfer Tunnel
Tlokeng, Lesotho
Site supervision (drilling, water pressure tests, installation of piezometers),
rotary core logging for the dam site, the saddle dam, the coffer dam, the
diversion tunnel, the Katse Dam transfer tunnel and the proposed borrow pits.
Geotechnical Investigation for Rietfontein Dam
Eastern Cape, South Africa
Project management, trial pitting for the dam foundation, spillway construction
and the construction material at the site. Evaluation of engineering properties of
subsurface material. Geotechnical reporting for dam design purposes.
Geotechnical investigation and reporting for construction material borrow pits.

Geotechnical Investigation for Darvil Dam

Pietermaritzburg, Kwa-Zulu Natal, South Africa
In-situ investigation including test pitting for geotechnical soil profiles of the
proposed dam site to determine the dam foundation depth. Project
management and selection of laboratory tests for study objectives subsequent
to the fieldwork. Compilation of a geotechnical report for the dam design and fr
the construction material.
Geotechnical Investigation for Gluckstadt Water Supply Scheme
Gluckstaadt, Kwa-Zulu Natal, South Africa
Site engineer responsible for augering and logging. Collation of data and report
writing including recommendations for the installation of the proposed pipeline.
Project manager ensuring the quality and client satisfaction.
Geotechnical Investigation for Nkobongweni Water Supply
Tugela Ferry, Kwa-Zulu Natal, South Africa
Project management and field geologist for the evaluation along the proposed
water supply pipeline, at the proposed borehole structures and at the proposed
reservoir. Assessment of geotechnical properties of potential bedding material
for construction. Ntabamhlophe Tank Project manager responsible for the
field investigation and the report writing for the proposed tank.
Geotechnical Investigation for Ntabamhlophe Tank
Wembezi, Kwa-Zulu Natal, South Africa
Project manager and client liaison. Field investigation including test pitting and
sampling. Report writing and foundation recommendation. Foundation
assessment during construction.

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Text Text

Geotechnical Investigation for Kenhardt Solar Farm

Kenhardt, Northern Cape, South Africa
Project and subcontract management. Drilling supervision, in-situ investigation
for site characterization. Management and selection of laboratory tests for study
objectives. Client liaison and geotechnical report for pylon foundations,
substation foundation and access road construction.
Geotechnical Desktop Assessment for the Dalmanutha Wind Energy
Facility
Belfast, Mpumalanga, South Africa
Project management and client liaison. Geotechnical desktop study for three
wind energy facilities and their associated structures to supplement a project
Environmental Impact Assessment.
Geotechnical Investigation for the Oya and Yemaya Solar and Wind
Energy Facility
Maitjiesfontein, Western Cape, South Africa
Geotechnical desktop study reports for the two sites for the two solar sites. Test
pitting and sample selection for required tests for the Oya site. Analysing and
interpreting fieldwork data and laboratory results.
Geotechnical Desktop Assessment for the Koup 1 and Koup 2 Wind
Energy Facility
Leeu Gamka, Western Cape, South Africa
Project management and client liaison. Geotechnical desktop study for two wind
energy facilities and their associated structures to supplement a project
Environmental Impact Assessment.
Geotechnical Desktop Assessment for three Wind Energy Facilities
Northern and Western Cape, South Africa
Project management and client liaison. Geotechnical desktop studies for the
proposed Brandvalley, Karreebosch and Rietkloof wind farm energy facilities
and three 33kV powerlines and their associated structures.
Geotechnical Desktop Assessment for Uvuvuselela Railway Line
Extensions
South Africa
Project management and client liaison. Geotechnical desktop studies for the
proposed Transnet Railway Loop extensions, Port Elizabeth Port extensions
and loading yards in Gauteng.
Geotechnical Gap Analysis for the Debswana Mine Facilities
Central District, Botswana
Geotechnical desktop study, gap analysis and additional investigation
executions plans for Damtshaa, Orapa and Letlhakane mine facilities.
Geotechnical Investigation for the N2 Pongola to Kangela
Kwa-Zulu Natal, South Africa
Field geologist responsible for trial pitting, logging, and sample collection for
laboratory analysis for the N2 construction borrow pits. Collation of field data
and laboratory data.
Geotechnical Investigation for the N3 Borrow Pits
Kwa-Zulu Natal, South Africa
Rotary core logging and percussion chips logging for the proposed borrow pits
located between Durban and Pietermaritzburg for the N3 construction.

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Geotechnical Investigation for the Mfulamuni Access Road and

Aggregates
Pomeroy, Kwa-Zulu Natal, South Africa
Project management and client liaison. Fieldwork for the realignment and the
re-gravelling of the Mfulamuni access road. Ensuring adequate laboratory
testing for the road and the potential borrow pits. Report compilation for the road
and the material investigation.

Geotechnical Investigation for the P77 Culverts

Dududu, Kwa-Zulu Natal, South Africa
Field engineering geologist responsible for trial pitting, logging and DPL testing
to determine the subsurface characteristics for the proposed seven culverts.
Compilation of an interpretive geotechnical report highlighting the foundation
depths for each culvert and the geotechnical constraints thereof.
Geotechnical Investigation for Kikwood to Addo Borrow Pit and Retaining
Walls
Kirkwood, Eastern Cape, South Africa
Soil profiling and interpretation of the field profiles and laboratory results for the
borrow pit and retaining walls. Material volume calculations for the borrow pits.
Dynamic cone penetration and interpretation for the competent foundations for
the retaining walls. Data assimilation and assessment for report writing
Geotechnical Investigation for Eastwood Pedestrian Bridge
Pietermaritzburg, Kwa-Zulu Natal, South Africa
Project management and client liaison for the construction of a pedestrian
bridge. Fieldwork including test pitting and DPL testing. Analysing and
interpreting the field data to recommend foundation levels.
Geotechnical Study for the Refurbishment of 9 Eskom Towers
Eastern Cape, South Africa
Test pitting for geotechnical ground profiles of each site. Management and
selection of laboratory tests for study objectives. Foundation recommendations
for each site. Geotechnical report for design purposes.
Geotechnical Investigation for Nkweletsheni Primary School
Richmond, Kwa-Zulu Natal, South Africa
Project management and client liaison school refurbishment. Test pitting,
percolation testing and DPL testing for geotechnical ground profiles of the site.
Management and selection of laboratory tests for study objectives.
Geotechnical report for foundations, recommendations for the soak-away and
for the multi purpose sports ground.
Geotechnical Investigation for Zwelisha Moyeni Water Treatment Works
Bergville, Kwa-Zulu Natal, South Africa
Project management and client liaison. Test pitting and DPL testing for
geotechnical ground profiles of the site. Management and selection of
laboratory tests for study objectives. Geotechnical report for foundations of
treatment works structure founded at depth of 4-5m below NGL.
Geotechnical Investigation for Hammersdale Waste-Water Treatment
Works
Hammersdale, Kwa-Zulu Natal, South Africa
Client liaison and project management. Subsurface profiling and DPL testing for
the extensions to the existing Hammersdale WWTW. Analysis of the profiles

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and selection of laboratory tests for study objectives. Data analysis and report
compilation for structure foundations.
Geotechnical Investigation for the Proposed Giba Industrial Development
Pinetown, Kwa-Zulu Natal, South Africa
Test pitting for soil profiling, disturbed and undisturbed sampling, delineation of
groudndwater seepage areas. Management and selection of laboratory tests.
Analysing and interpretation of laboratory test results. Compilation of
geotechnical report for foundations and groundwater management
recommendations.
Geotechnical Investigation for the Cornubia Fills
Cornubia, Kwa-Zulu Natal, South Africa
Project management and client liaison. In-situ testing for geotechnical soil
profiles of the site and general site characterization for fills for the proposed
housing development. Engineering geological report for the study for the fills.
Reviewing the rotary drilling report for the client.
Geotechnical Investigation for Ward 7 Community Hall
Taylors Halt, Kwa-Zulu Natal, South Africa
Project management and liaising with Client. Conducting the geotechnical
investigation that included trial pitting, laboratory testing and percolation testing.
Fieldwork and laboratory data processing for geotechnical report compilation.
Geotechnical Investigation for Mandalathi Community Hall
Kwa-Zulu Natal, South Africa
Project management and liaising with Client. Conducting the geotechnical
investigation that included trial pitting, laboratory testing and percolation testing.
Fieldwork and laboratory data processing for geotechnical report compilation.
Geotechnical Investigation for Austerville Sites
Durban, Kwa-Zulu Natal, South Africa
Project management and client liaison. In situ soil profiling and interpretation of
the profiles. Consistency tests (DPL) and interpretation of the results evaluate

for temporary housing development and recommending relevant foundation

measures.
Geotechnical Investigation for five ADA Rabbitry Sites
Kwa-Zulu Natal, South Africa
Project management and client liaison. In situ soil profiling and interpretation of
the profiles. Consistency tests (DPL) and interpretation of the results evaluate
the EASPB and sample collection for laboratory analysis. Report compilation
with foundation recommendations.
Geotechnical Investigation for Several Intaba Ridge Estate Houses
Pietermaritzburg, Kwa-Zulu Natal, South Africa
Project management and client liaison with several property developers. In situ
soil profiling, conducting in-situ consistency tests (DPL) and sampling for

house developments and recommending foundation depths and types as per

NHBRC guidelines.
Geotechnical Investigation for a Proposed Student Accommodation
Pietermaritzburg, Kwa-Zulu Natal, South Africa
Project management and client liaison for the proposed three storey student
accommodation development. In situ soil profiling, conducting in-situ

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consistency tests (DPL) and sampling for laboratory analysis. Report writing to

foundation depths and type as per NHBRC guidelines.

Geotechnical Investigation for the 220 Murray Road Development
Pietermaritzburg, Kwa-Zulu Natal, South Africa
Project management and client liaison. Report writing and field data analysis for
the infill geotechnical investigation report for a multi-story development in
Hayfields. The development includes a school, a shopping complex, a drive
through, a petrol filling station and a residential area.
Geotechnical Investigation for the Heidelberg Cemetery Extension
Heidelberg, Gauteng, South Africa
Project management and client liaison for the extension of the existing
Heidelberg cemetery. Subsurface profiling and interpretation of the profiles.
Field sampling for laboratory analysis. Geotechnical report writing and
evaluating the site as per the South African Council for Geoscience Guidelines
for Cemeteries.
Geotechnical Investigation for Three Proposed Umhlathuze Cemeteries
Empangeni, Kwa-Zulu Natal, South Africa
Project management and client liaison for the development of three cemetery
sites. Subsurface profiling, percolation testing and field sampling for laboratory
analysis. Geotechnical report writing, evaluating nd rating the sites as per the
South African Council for Geoscience Guidelines for Cemetery Development.
Geotechnical Investigation for the Proposed Alfred Duma Cemeteries
Ladysmith, Kwa-Zulu Natal, South Africa
Project management and client liaison for the development of cemetery sites I
the municipality. Geotechnical desktop studies to evaluate and rate the
proposed sites in Colenso, Ladysmith and Ezakheni. The desktop study reports
were written as per the South African Council for Geoscience Guidelines for
Cemeteries.
Geotechnical Investigation for the Closure of Acaciavale Landfill Site
Ladysmith, Kwa-Zulu Natal, South Africa
Fieldwork including test pit profiling and interpretation from test pitting and
sampling for study objectives. Data analysis and report compilation for the
closure of the landfill site and recommendations on closure material.
Geotechnical Investigation for the Proposed Danskraal Landfill Site
Ladysmith, Kwa-Zulu Natal, South Africa
Geotechnical desktop study report including GIS work to identify and shortlist
potential landfill sites. Fieldwork including test pit profiling and interpretation
from test pitting for landfill site development investigation. Data analysis and
report compilation.
Site Supervision for the Proposed UMgungundlovu Landfill Site
Pietermaritzburg, Kwa-Zulu Natal, South Africa
Supervision for the percussion drilling contract for the proposed new landfill site.
Subcontractor management and client liaison. Percussion chip logging.
Borehole water level and yield measurements. Hydrocensus and sampling
existing boreholes in a 1km radius.
Agricultural Soil Survey for the Harry Gwala District Municipality
Umzimkhulu, Kwa-Zulu Natal, South Africa

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Project management and client liaison. Agricultural soil survey and sampling.
Data analysis and report compilation for the agricultural potential and the
irrigation potential of 7500ha land in the district municipality. Presentation of the
final findings to the client.

TRAINING

ArcGIS1, Introduction to Geographic Information System, JG Afrika, 2018

Civil Engineering and Renewable Energy, Geopile Africa, 2020

Geotubes and Dewatering, Kaytech, 2019

Site Monitoring Workshop, JG Afrika, 2019

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APPENDIX B

Geotechnical Impact Assessment

IMPACT ASSESSMENT METHODOLOGY

SCOPING PHASE

REPORTING REQUIREMENTS
Project Description

Legislative Context (as applicable)

Assumptions and limitations

Description of Baseline Environment including sensitivity mapping

Identification and high-level screening of impacts

Plan of Study for EIA

HIGH-LEVEL SCREENING OF IMPACTS AND MITIGATION

Appendix 2 of GNR 982, as amended, requires the identification of the significance of potential impacts during scoping. To this
end, an impact screening tool has been used in the scoping phase. The screening tool is based on two criteria, namely probability;
and, consequence (Table 0-3), where the latter is based on general consideration to the intensity, extent, and duration.

The scales and descriptors used for scoring probability and consequence are detailed in Table 0-1 and Table 0-2 respectively.
Table 0-1: Significance Screening Tool

CONSEQUENCE SCALE
PROBABILITY 1 2 3 4
SCALE 1 Very Low Very Low Low Medium

2 Very Low Low Medium Medium

3 Low Medium Medium High

4 Medium Medium High High

Table 0-2: Probability Scores and Descriptors

SCORE DESCRIPTOR
4 Definite: The impact will occur regardless of any prevention measures

3 Highly Probable: It is most likely that the impact will occur

2 Probable: There is a good possibility that the impact will occur

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1 Improbable: The possibility of the impact occurring is very low

Table 0-3: Consequence Score Descriptions

SCORE NEGATIVE POSITIVE

4 Very severe: An irreversible and permanent change Very beneficial: A permanent and very substantial benefit to
to the affected system(s) or party(ies) which cannot the affected system(s) or party(ies), with no real alternative
be mitigated. to achieving this benefit.

3 Severe: A long term impacts on the affected Beneficial: A long term impact and substantial benefit to the
system(s) or party(ies) that could be mitigated. affected system(s) or party(ies). Alternative ways of
However, this mitigation would be difficult, achieving this benefit would be difficult, expensive or time
expensive or time consuming or some combination of consuming, or some combination of these.
these.

2 Moderately severe: A medium to long term impacts Moderately beneficial: A medium to long term impact of
on the affected system(s) or party (ies) that could be real benefit to the affected system(s) or party(ies). Other
mitigated. ways of optimising the beneficial effects are equally
difficult, expensive and time consuming (or some
combination of these), as achieving them in this way.

1 Negligible: A short to medium term impacts on the Negligible: A short to medium term impact and negligible
affected system(s) or party(ies). Mitigation is very benefit to the affected system(s) or party(ies). Other ways of
easy, cheap, less time consuming or not necessary. optimising the beneficial effects are easier, cheaper and
quicker, or some combination of these.

The nature of the impact must be characterised as to whether the impact is deemed to be positive (+ve) (i.e. beneficial) or negative
(-ve) (i.e. harmful) to the receiving environment/receptor. For ease of reference, a colour reference system (Table 0-4) has been
applied according to the nature and significance of the identified impacts.
Table 0-4: Impact Significance Colour Reference System to Indicate the Nature of the Impact

Negative Impacts (-ve) Positive Impacts (+ve)

Negligible Negligible

Very Low Very Low

Low Low

Medium Medium

High High

Page 2
EIA PHASE

REPORTING REQUIREMENTS
Project Description

Legislative Context (as applicable)

Assumptions and limitations

Description of methodology (as required)

Update and/or confirmation of Baseline Environment including update and / or confirmation of sensitivity mapping

Identification and description of Impacts

Full impact assessment (including Cumulative)

Mitigation measures

Impact Statement

ASSESSMENT OF IMPACTS AND MITIGATION

The assessment of impacts and mitigation evaluates the likely extent and significance of the potential impacts on identified
receptors and resources against defined assessment criteria, to develop and describe measures that will be taken to avoid, minimise
or compensate for any adverse environmental impacts, to enhance positive impacts, and to report the significance of residual
impacts that occur following mitigation.
The key objectives of the risk assessment methodology are to identify any additional potential environmental issues and
associated impacts likely to arise from the proposed project, and to propose a significance ranking. Issues / aspects will be
reviewed and ranked against a series of significance criteria to identify and record interactions between activities and aspects, and
resources and receptors to provide a detailed discussion of impacts. The assessment considers direct 1, indirect2, secondary3 as well
as cumulative4 impacts.
A standard risk assessment methodology is used for the ranking of the identified environmental impacts pre-and post-mitigation
(i.e. residual impact). The significance of environmental aspects is determined and ranked by considering the criteria 5 presented in
Table 0-5.
Table 0-5: Impact Assessment Criteria and Scoring System

CRITERIA SCORE 1 SCORE 2 SCORE 3 SCORE 4 SCORE 5

Impact Magnitude (M) Very low: Low: Medium: High: Very High:
The degree of alteration of the affected No impact on Slight impact on Processes Processes Permanent
environmental receptor processes processes continue but in a temporarily cessation of
modified way cease processes

1 Impacts that arise directly from activities that form an integral part of the Project.
2 Impacts that arise indirectly from activities not explicitly forming part of the Project.
3 Secondary or induced impacts caused by a change in the Project environment.
4 Impacts are those impacts arising from the combination of multiple impacts from existing projects, the Project and/or future projects.
5 The definitions given are for guidance only, and not all the definitions will apply to all the environmental receptors and resources being

assessed. Impact significance was assessed with and without mitigation measures in place.
Page 3
CRITERIA SCORE 1 SCORE 2 SCORE 3 SCORE 4 SCORE 5

Impact Extent (E) The geographical Site: Site only Local: Inside Regional: National: International:
extent of the impact on a given activity area Outside activity National scope Across borders
environmental receptor area or level or boundaries
Impact Reversibility (R) The ability Reversible: Recoverable: Irreversible: Not
of the environmental receptor to Recovery Recovery with possible despite
rehabilitate or restore after the activity without rehabilitation action
has caused environmental change rehabilitation
Impact Duration (D) The length of Immediate: Short term: Medium term: Long term: Permanent:
permanence of the impact on the On impact 0-5 years 5-15 years Project life Indefinite
environmental receptor
Probability of Occurrence (P) The Improbable Low Probability Probable Highly Definite
likelihood of an impact occurring in the Probability
absence of pertinent environmental
management measures or mitigation
Significance (S) is determined by
combining the above criteria in the
following formula:

IMPACT SIGNIFICANCE RATING

Total Score 4 to 15 16 to 30 31 to 60 61 to 80 81 to 100

Environmental Significance Rating Very low Low Moderate High Very High
(Negative (-))
Environmental Significance Rating Very low Low Moderate High Very High
(Positive (+))

IMPACT MITIGATION
The impact significance without mitigation measures will be assessed with the design controls in place. Impacts without

facilitate understanding of how and why mitigation measures were identified. The residual impact is what remains following the
application of mitigation and management measures and is thus the final level of impact associated with the development.
Residual impacts also serve as the focus of management and monitoring activities during Project implementation to verify that
actual impacts are the same as those predicted in this report.
The mitigation measures chosen are based on the mitigation sequence/hierarchy which allows for consideration of five (5)
different levels, which include avoid/prevent, minimise, rehabilitate/restore, offset and no-go in that order. The idea is that when
project impacts are considered, the first option should be to avoid or prevent the impacts from occurring in the first place if
possible, however, this is not always feasible. If this is not attainable, the impacts can be allowed, however they must be
minimised as far as possible by considering reducing the footprint of the development for example so that little damage is
encountered. If impacts are unavoidable, the next goal is to rehabilitate or restore the areas impacted back to their original form
after project completion. Offsets are then considered if all the other measures described above fail to remedy high/significant
residual negative impacts. If no offsets can be achieved on a potential impact, which results in full destruction of any ecosystem
for example, the no-go option is considered so that another activity or location is considered in place of the original plan.
The mitigation sequence/hierarchy is shown in Figure 1 below.

Page 4
Figure 1: Mitigation Sequence/Hierarchy

Page 5
Project Name H b
Impact Assessment

Impact Pre-Mitigation Post-Mitigation Mitigation Measures

Aspect Description Stage Character Ease of Mitigation
number (M+ E+ R+ D)x P= S Rating (M+ E+ R+ D)x P= S Rating
The displacement of natural earth
material and overlying vegetation leading
to:

of vegetation.
Impact 1: Soil Erosion Construction Negative 4 3 3 3 5 65 N4 2 1 1 2 2 12 N1

as into surrounding drainage channels

leading to sedimentaton.

exacerbated during periods of heavy

rainfall.
Significance N4 - High N1 - Very Low
Contamination of ground and surface
water resources from heavy plant leading propoer soil protection.
Impact 2: Oil Spillages Construction Negative 5 3 5 5 5 90 N5 2 2 3 1 2 16 N2
to quality deterioration of the water
resources.
Significance N5 - Very High N2 - Low

Impact Pre-Mitigation Post-Mitigation

Receptor Description Stage Character Ease of Mitigation
number (M+ E+ R+ D)x P= S (M+ E+ R+ D)x P= S

Displacement of natural earth material

Impact 1: Soil Erosion Operational Negative 2 1 3 2 2 16 N2 1 1 1 1 1 4 N1
during maintenance

Significance N2 - Low #N/A

Potential oil spillages from service

Impact 2: Potential Oil Spillages Operational Negative 3 2 5 5 3 45 N3 2 1 3 2 2 16 N2
vehicles and heavy plant.

Significance N3 - Moderate N2 - Low

Impact Pre-Mitigation Post-Mitigation

Receptor Description Stage Character Ease of Mitigation
number (M+ E+ R+ D)x P= S (M+ E+ R+ D)x P= S

temporary berms and drainage channels to divert

surface water.
clearance of structures.
Impact 1: Erosion Decommissioning Negative 4 2 3 3 4 48 N3 2 1 1 2 2 12 N1
Rehabilitation of affected areas (such as revegetation).
vegettion by vehicles
Reinstate channelized drainage features.
Significance N3 - Moderate N1 - Very Low

Impact 2: Potential oil spillages Decommissioning Negative 4 3 5 5 4 68 N4 3 1 3 1 2 16 N2 propoer soil protection.

of structures.

Significance N4 - High N2 - Low

Impact Pre-Mitigation Post-Mitigation

Receptor Description Stage Character Ease of Mitigation
number (M+ E+ R+ D)x P= S (M+ E+ R+ D)x P= S
The displacement of natural earth
material and overlying vegetation leading temporary berms and drainage channels to divert
to: surface water.

Rehabilitation of affected areas (such as revegetation).

Impact 1: Erosion Cumulative Negative 3 2 3 3 4 44 N3 2 1 1 2 2 12 N1
channels leading to sedimentaton. Reinstate channelized drainage features.

exacerbated during periods of heavy

rainfall.
Significance N3 - Moderate N1 - Very Low
Contamination of ground and surface
water resources from heavy plant leading
Impact 2: Potential Oil Spillages Cumulative Negative 4 3 5 5 4 68 N4 2 1 3 1 2 14 N1 propoer soil protection.
to quality deterioration of the water
resources.
Significance N4 - High N1 - Very Low
18 May 2023 21500715-352637-3_Rev2

APPENDIX C

Document Limitations
 WSP

i) This Document has been prepared for the particular purpose outlined in WSP
accepted for the use of this Document, in whole or in part, in other contexts or for any other purpose.
ii) The scope and the period of WSP es are as described in WSP
and limitations. WSP did not perform a complete assessment of all possible conditions or circumstances that
may exist at the site referenced in the Document. If a service is not expressly indicated, do not assume it has
been provided. If a matter is not addressed, do not assume that any determination has been made by WSP in
regard to it.

iii) Conditions may exist which were undetectable given the limited nature of the enquiry WSP was retained to
undertake with respect to the site. Variations in conditions may occur between investigatory locations, and there
may be special conditions pertaining to the site which have not been revealed by the investigation and which
have not therefore been taken into account in the Document. Accordingly, additional studies and actions may be
required.

iv) In addition, it is recognised that the passage of time affects the information and assessment provided in this
Document. WSP that existed at the time of the production of the
Document. It is understood that the Services provided allowed WSP to form no more than an opinion of the
actual conditions of the site at the time the site was visited and cannot be used to assess the effect of any
subsequent changes in the quality of the site, or its surroundings, or any laws or regulations.

v) Any assessments made in this Document are based on the conditions indicated from published sources and the
investigation described. No warranty is included, either express or implied, that the actual conditions will conform
exactly to the assessments contained in this Document.

vi) Where data supplied by the client or other external sources, including previous site investigation data, have been
used, it has been assumed that the information is correct unless otherwise stated. No responsibility is accepted
by WSP for incomplete or inaccurate data supplied by others.

vii) The Client acknowledges that WSP may have retained sub-consultants affiliated with WSP to provide Services
for the benefit of WSP. WSP will be fully responsible to the Client for the Services and work done by all its sub-
consultants and subcontractors. The Client agrees that it will only assert claims against and seek to recover
losses, damages or other liabilities from WSP and not WSP
allowed by law, the Client acknowledges and agrees it will not have any legal recourse, and waives any expense,
loss, claim, demand, or cause of action, against WSP filiated companies, and their employees, officers and
directors.
viii) This Document is provided for sole use by the Client and is confidential to it and its professional advisers. No
responsibility whatsoever for the contents of this Document will be accepted to any person other than the Client.
Any use which a third party makes of this Document, or any reliance on or decisions to be made based on it, is
the responsibility of such third parties. WSP accepts no responsibility for damages, if any, suffered by any third
party because of decisions made or actions based on this Document.

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