Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Brak River stream profiling Study for the proposed Berenice Colliery in ward 21 of the Makhado Local Municipality in the Vhembe District of the Limpopo Province
Dihlashana Consulting Corporation (Pty) Ltd
Maxwell Office Park Building 1, Magwa Crescent West,
Waterfall City, Midrand, 1685
Contact Details: +27 11 254 4800/ 072 899 3300/ 084 397 4840
Contact Person: Dipitseng Manamela
Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Title Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province Issue 02 Date 28 March 2017 Classification Privileged Status Draft
Details of the Applicant
Company Details
Name Universal Coal Development II (Pty) Ltd
Responsible Person Ms. Minah Moabi
Contact Person Project Manager
Contact Details 012 460 0805
Address P O Box 0075
Brooklyn Square
0075
Consultant Details
Company Dihlashana Consulting Corporation (Pty) Ltd
Compiled by Mpho Ramalivhana,
Qualification BSc Hons (Botany)
Affiliation SACNASP (400395/14), IAIAsa and SAAB
Contact Details 072 899 3300
Reviewed by Lazola Mnyaka
Qualification BSS Hons (Geography and Environmental Management)
Approved by Dipitseng Manamela
Qualification MSc (Environmental Science)
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Contents
GLOSSARY ...... 6
ACRONYMS ...... 7
1. INTRODUCTION ...... 8
1.1 Aim and Objectives ...... 9
1.2 Study Limitations ...... 9
2. STUDY AREA ...... 10
2.1 Locality ...... 10
2.2 Water Management Area ...... 11
2.3 Ecoregion ...... 12
2.4 Vegetation ...... 14
2.4.1 Biome ...... 14
2.4.2 Broad-vegetation ...... 14
3. MATERIALS AND METHODS...... 16
3.1. Desktop study ...... 16
3.2. Site Assessment ...... 16
3.3. Water Quality Analysis ...... 16
3.4. Invertebrate Habitat Assessment...... 16
3.5. Aquatic Macro Invertebrates ...... 16
4. FINDINGS AND DISCUSSION ...... 17
4.1. Habitat integrity/Suitability ...... 17
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
5. Impact Assessment and mitigation measures ...... 26
5.1. Methodology in determine significance ...... 26
5.1.1. Consequence ...... 26
5.1.2. Likelihood ...... 28
5.1.3. Environmental Significance ...... 29
5.2. Impact assessment ...... 29
5.2.1. Construction phase ...... 29
5.2.2. Operational phase ...... 33
6. Conclusion and recommendations ...... 36
7. REFERENCES ...... 37
List of figures
Figure 1: Locality Map for the proposed Berenice Colliery ...... 11
Figure 2: Limpopo Quaternary Catchment ...... 12
Figure 3: Level 1 Ecoregions of South Africa ...... 13
Figure 4: Vegetation map for the proposed site ...... 15
List of Tables
Table 1: Summary of the location of study area ...... 10
Table 2: Habitat Integrity Categories ...... 17
Table 3: Sites Characterization ...... 19
Table 4: Assessment and Rating of Severity ...... 26
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Table 5: Assessment and Rating of Duration ...... 27
Table 6: Assessment and Rating of Extent ...... 27
Table 7: Determination of Consequence ...... 28
Table 8: Assessment and Rating of Frequency ...... 28
Table 9: Assessment and Rating of Probability...... 28
Table 10: Determination of Likelihood ...... 29
Table 11: Determination of Environmental Significance ...... 29
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
GLOSSARY
Aquatic ecosystem: ecosystem which provides a medium for habitat by aquatic organisms and sustains aquatic ecological process.
Biomonitoring: the gathering of biological information in both the laboratory and the field for the purpose of making an assessment or decision or in determining whether quality objectives are being met.
Ecosystem: any unit that includes all of the organisms (i.e. the community) in a given area interacting with the physical environment so that a flow of energy leads to clear defined trophic structure, biodiversity and material cycles (i.e. exchange of material between living and non-living parts) within the ecosystem.
Geomorphology: the study of the origin of secondary topographic features which are carved by erosion in the primary elements and built up of the erosional debris.
Instream vegetation: submerged vegetation, including algal mats. Maybe in-current or out-of-current.
Invertebrates: animal lacking backbone and internal skeleton.
Marginal vegetation: emergent vegetation associated with river banks. Synonymous with fringing vegetation. Maybe in-current or out-of-current.
Macro-invertebrates: invertebrates retained by mesh size 200µm.
Riparian: living or located on the banks of streams or rivers.
Suspended Solids: inorganic and organic matter, such as clay, minerals, decay products and living organisms, that remains in suspension in water. In surface waters it is usually associated with erosion or runoff after rainfall events.
Taxon (plural Taxa): general term for a taxonomic group in a formal system of nomenclature, whatever its rank. A taxonomic group refers to the systematic ordering and naming of plants and animals according to their presumed natural relationships.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
ACRONYMS
ASPT Average Score Per Taxa
DO Dissolved Oxygen
DS Downstream
EC Electrical Conductivity
EC50 50% Effective Concentration
GPS Global Positioning System
IHAS Invertebrate Habitat Assessment System
PES Present Ecological Status
RHP River Health Programme
SASS5 South African Scoring System
TDS Total Dissolved Salts
TSS Total Suspended Solids
TWQR Target Water Quality Range
US Upstream
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
1. INTRODUCTION South Africa is a semi-arid country with only 8.6% of the rainfall available as surface water. South Africa’s rainfall is almost 400mm below the worldwide average of 860mm a year, the lowest conversions in the world. Therefore, responsible utilisation of water in a sustainable manner is essential for the future of the country. The freshwater resources of the country are already under stress. For instance, most of the country’s major rivers have been dammed to provide water for the increasing population (Davies, et al., 1993). In more than half of the country, South Africans are using more water than what’s available. South Africans are already using 98% of available water supply, and a staggering 37% of clean, drinkable water is being lost through inefficient ways of using water such as leaking pipes, dripping taps – and that is what’s being reported, the figure could be much higher” (Thelwell, 2014).
The scarcity of water is compounded by pollution of the surface and ground water resources. Typical pollutants of South Africa’s fresh water include industrial effluents, domestic and commercial sewage, acid mine drainage (AMD), agricultural run-off and litter (Hobbs and Kennedy, 2011). The availability of water, now and in the future, is heavily dependent on climate, water use and management and land use practice (Walmsley, et al., 1999).
Aquatic ecosystem can be defined as any unit that includes all of its organisms in a given area, interacting with the physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity and material cycles within the system (Odum, 1971). The ecological integrity of ecosystem can be defined as the ability of the system to support and maintain a balanced, integrated composition of physico-chemical and habitat characteristics, as well as biotic components on temporal and spatial scale, that are comparable to the natural state of that ecosystem. It therefore, refers to the structure and functioning of an ecosystem under natural conditions or a state unimpaired by anthropogenic stresses (Roux, 1999).
It can therefore, be deduced that the overall ecological integrity of a system is determined by the following aspects, its physical, physic-chemical and biological (biotic) integrity and energy source input. In nature these aspects cannot be seen as separate entities as they are interlinked.
To investigate the water quality in the Brak River and its network/system linked with the proposed site for the development of the Berenice Colliery, Headwaters cc appointed Dihlashana Consulting Corporation (Pty) Ltd to undertake ecological assessment of aquatic ecosystem to determine the aquatic health of the Brak River and the possible impacts that the proposed mine might cause on the stream (watercourse). This report is based on the findings gained during the first quarter (Month of February) of 2017. The assessment protocol applied in this study will give a clear reflection of the potential impacts on aquatic ecosystems. The study includes the assessment of general habitat condition and availability as well as biotic integrity.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
1.1 Aim and Objectives
It is a legal requirement (National Water Act, 36 of 1998) to monitor the quality and effect of discharged water into an aquatic ecosystem. The primary objective of this study was to assess the quality of aquatic resources associated with the proposed Berenice Colliery. In order to achieve this, the following objectives have been assigned:
To assess the state of aquatic ecosystem upstream and downstream of the proposed Berenice Colliery on the Brak River; To understand the variation of water quality upstream and downstream of the proposed Berenice Colliery on the Brak River; To assess and identify potential possible impacts, and To develop mitigation measures.
1.2 Study Limitations
The following limitations were identified during the assessment:
During the assessment all sites were dry. Due to this, water quality analysis and aquatic assessment (SASS5) were not undertaken. Information from Department of Water and Sanitation (both national and provincial) were sought but nothing regarding the Brak River in the Limpopo Province could be found.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
2. STUDY AREA
2.1 Locality
The proposed Berenice Colliery is located in Ward 21 of Makhado Local Municipality within Vhembe District Municipality, Limpopo Province. The project site is approximately 110 km North West of Makhado in Limpopo Province, between the town of Vivo and Alldays. The site is approximately 1800 ha in extent and bordered to the north-west by the Brak River, which is a non-perennial tributary of the Sand River. The table below indicates the site codes, river/stream, and GPS co-ordinates of each sampling point.
Table 1: Summary of the location of study area
Stream CODE GPS Locations (WGS84) Point Latitude (S) Longitude (E) number 1 Brak River DS 22° 40’ 24.6” 29° 30’ 55.4” 2 Brak River US 22° 44’ 49.8” 29° 22’ 10.6” 3 Drainage line to the Brak River DL 1 22° 40’ 19.7” 29° 30’ 10.4” DL 2 22° 40’ 36.2” 29° 29’ 42.9” 4 Drainage line to the Brak River DL 3 22° 43’ 44.2” 29° 25’ 13.8” 5 Drainage line to the Brak River DL 4 22° 40’ 45.03” 29° 23’ 11.17” 6 Drainage line to the Brak River Dl 5 22° 44’ 31.98” 29° 22’ 43.05” 7 Drainage line to the Brak River
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Figure 1 below presents the locality map for the sampling points against the proposed site for the proposed Berenice Colliery Mine.
Figure 1: Locality Map for the proposed Berenice Colliery
2.2 Water Management Area The study area falls within the rivers and streams of the Limpopo Water Management Area (WMA), more specifically in the A71J and A72B quaternary catchment areas. Major rivers within this WMA include the Limpopo, Matlabas, Mokolo, Lephalala, Mogalakwena Sand and Nzhelele. The study area is however located adjacent to the Brak River which is the tributary of the Sand River.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Figure 2: Limpopo Quaternary Catchment
2.3 Ecoregion
An Ecoregion is an area with similar physical characteristics, and is expected to support a unique combination of flora and fauna (Kleynhans et al, 2007). The study area is located within Level 1 Ecoregion (Limpopo Plain). This Ecoregion is characterized by plains and lowlands with a low moderate relief and vegetation consisting mostly of Bushveld types and Mopane veld. Generally, this is a low lying, dry to arid, hot region with virtually no perennial streams originating in the area itself.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Figure 3: Level 1 Ecoregions of South Africa
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
2.4 Vegetation
2.4.1 Biome Mucina and Rutherfordl (2010) described the project as falling within the Savanna Biome. The Savanna Biome is the largest Biome in southern Africa, occupying 46% of its area, and over one-third the area of South Africa. It is well developed over the lowveld and Kalahari region of South Africa and is also the dominant vegetation in neighbouring countries such as Botswana, Namibia and Zimbabwe. It is characterized by a grassy ground layer and a distinct upper layer of woody plants. Where this upper layer is near the ground vegetation may be referred to as Shrubveld, where it is dense as Woodland, and the intermediate stages are locally known as Bushveld.
The environmental factors delimiting the biome are complex: altitude ranges from sea level to 2000 m; rainfall varies from 235 to 1000 mm per year; frost may occur from 0 to 120 days per year; and almost every major geological and soil type occurs within the biome. A major factor delimiting the biome is the lack of sufficient rainfall which prevents the upper tree layer from dominating, coupled with fires and grazing, which keep the grass layer dominant. Summer rainfall is essential for grass dominance, which, with its fine material, fuels near-annual fires. In fact, almost all species are adapted to survive fires, usually with less than 10% of plants, both in the grass and tree layer, killed by fire. Even with severe burning, most species can re-sprout from the stem bases.
The grass layer is dominated by C 4-type grasses, which are at an advantage where the growing season is hot. But where rainfall has a stronger winter component, C 3-type grasses dominate. The shrub-tree layer may vary from 1 to 20 m in height, but in Bushveld typically varies from 3 to 7 m. The shrub-tree element may come to dominate the vegetation in areas which are being overgrazed. Most of the savanna vegetation types are used for grazing, mainly by cattle or game. In the southernmost savanna types, goats are a major stock. In some areas crops and subtropical fruit are cultivated. These mainly include the Clay Thorn Bushveld, parts of Mixed Bushveld, and Sweet Lowveld Bushveld.
Conservation status of savanna is comparatively good, mainly due to the presence of the Kruger and Kalahari Gemsbok National Parks within the biome. However, the high area conserved in South Africa, belies the fact that half of savanna vegetation types are inadequately conserved, in having less than 5% of their area in reserves and, much of the area is used for game-farming and can thus be considered effectively preserved, provided that sustainable stocking levels are maintained. The importance of tourism and big game hunting in the conservation of the area must not be underestimated.
2.4.2 Broad-vegetation
The study area falls within the Musina Mopane Bushveld (SVmp 1). The vegetation unit is distributed in Limpopo Province: undulating plains around Baines Drift and Alldays in the west, remaining north of the Soutpansberg and south of the Limpopo River, through Musina and Tshipise to Malongavlakte, Masisi and Banyinyi in the east.
14 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
The vegetation unit receives summer rainfall with very dry winters. The mean annual precipitation ranges about 300-400 mm with frost fairly infrequent. This vegetation unit is classified as Least Threatened with the target of 19% with about 2% conserved in the statutorily reserves mainly in the Mapungubwe National Park and the Nwanedi and Honnet Nature Reserves.
Figure 4: Vegetation map for the proposed site
15 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
3. MATERIALS AND METHODS
3.1. Desktop study
A desktop study was undertaken to gather background information pertaining to the proposed culverts sites. This includes assessment of general habitat condition and availability as well as biotic integrity.
3.2. Site Assessment
This entails assessing the area visually and identifying possible impacts that might occur as a result of the proposed project activities. In addition, photographs of each site are taken in order to present the condition of the area at the time of survey (10th February 2017). The following factors were taken into consideration;
Channel condition; Channel morphology; and Riparian vegetation cover.
3.3. Water Quality Analysis
During the survey period all monitoring sites were dry. Due to that both in situ and laboratory water quality analysis were not undertaken.
3.4. Invertebrate Habitat Assessment
The main aim of habitat assessment is to evaluate the suitability for a given organism to persist within a specific area. An organism will only remain at a site if suitable habitat and/or food are available and it is therefore essential to assess not only the habitat quantity but also the diversity of available biotopes. Due to the dryness of the area Invertebrate Habitat Assessment (IHAS) protocol was not applicable in all sites during the survey.
3.5. Aquatic Macro Invertebrates
The SASS5 protocol is used as a biotic index to quantify the Present Ecological State (PES) of the stream. This method entails the collection and identification of aquatic macro-invertebrates in three distinct biotopes, namely stones/bedrock, marginal and aquatic vegetation, and gravel/sand/mud (in and out-of-current). Sensitivity ratings are allocated to each taxon, and these ranges from 1 (very tolerant) to 15 (very sensitive to pollution). The scores of taxa encountered within the different biotopes at a selected monitoring point are added to determine a Total SASS5 Score, and the total is then divided by the number of families encountered to determine the Average Score Per Taxon (ASPT). However, due to the dry conditions the SASS5 assessment was not applicable to all sites during the survey and as such this led to conducting stream profiling.
16 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
4. FINDINGS AND DISCUSSION
This section describes all monitoring sites along with detailed findings which include photos and tables presenting the ecological status at each site. It should be noted that most of the aquatic (biological) assessment methods mentioned in the previous section above were not applicable due to the lack of water flow during the survey period, 10th February 2017. However, information regarding he previous water quality and aquatic health of the Brak River was sought from the Department of Water and Sanitation but to no success.
4.1. Habitat integrity/Suitability
The habitat integrity assessment is based on the assessment of the impacts of two components of the river, the riparian zone and instream habitat. The quality of the instream and riparian habitat has a direct influence on the aquatic community. The availability of and diversity of habitats are major determinants of aquatic biota that are present in the stream. Therefore, it is important to assess the impacts of human disturbance on riparian and instream habitat such as bed and channel modification, invasive plants, reduction and transformation of indigenous riparian plants and litter. The tabulation below presents the habitat integrity categories.
Table 2: Habitat Integrity Categories
Category Invertebrate Habitat Description Score (% of total)
A Unmodified, natural 90-100
B Largely natural with few modifications. A small change in the natural habitats 80-89 and biota may have taken place but the ecosystem functions are essentially unchanged.
C Moderately modified. A loss and change of natural habitat and biota have 60-79 occurred but the basic ecosystem functions are still predominantly unchanged.
D Largely modified. A large loss of natural habitat, biota and basic ecosystem 40-59 functions has occurred.
E The loss of natural habitat, biota and basic ecosystem functions is extensive. 20-39
F Modification has reached a critical level and the lotic system has been <20 modified completely with an almost complete loss of natural habitat and biota.
17 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
The habitat integrity of the watercourses in the study area was homogenous and largely modified (C/D). The major impact pressure within the area ranges from road, cultivation, stock grazing and other domestic land uses.
In addition, the riparian vegetation/zone was largely modified in all monitoring sites. The major impacts include vegetation transformation, livestock grazing, farming and pollution (waste). The impact on the aquatic ecosystem is increased by lack of good marginal vegetation. Furthermore, the greater concern was the high degree of domestic waste especially nappies in almost all the monitoring sites. Human excretes contain a wide variety of dissolved and suspended impurities which contain disease-causing microbes to human and also animals. Table 3 indicates the condition of all monitoring sites during the survey.
18 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Table 3: Sites Characterization
Site Site Description and observation
The site is located under a bridge and just after the proposed site of the Berenice Colliery, The site is charachterised by terrestrial plant species such as Acacia nigrescens, Cinerea dichrostachys, Grewia Flava. The grass layer is also terrestrial grasses than aquatic. Invasive species such as Xanthium sibiricum, Datura stramonium, Argemone Americana and Ricinus communis occur on the banks of the river. No water was following. No signs of erosion of pollution was noted on site
Picture 1: Downstream point of the Brak River
19 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Site Site Description and observation
This is site is located downstream of Kudu Lodge. A pool of water was encountered onsite but SASS 5 could not be conducted due to no flow of water. Also the site is characterized by more of terrestrial plants such as Ziziphus mucronata, Combretum apiculatum, Melia azedarach, and Grewia occidentalis. Invasive plants such as Xanthium sibiricum and Solanum mariantanum were recorded. No signs of erosion or any dumping was recorded or seen on site. Erosion and bank scouring was visible.
Picture 2: Upstream point of the Brak River
20 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Site Site Description and observation
This point is located west of the downstream point. It is located on a non-perennial stream that collects water from the neighboring farm prior to it reaching the Brak River The site was found to be shallow and dry charachterised by fine sand Grass species such as Aristida adscensionis, Eragrostis lehmanniana, Melinis repens were recorded. With tall species such as Cinerea dichrostachys, Grewia occidentalis and Grewia bicolor noticed.
Picture 3: DL 1 point
21 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Site Site Description and observation
The site/point is located on a non-perennial drainage line flowing to the Brak River. No water was encountered. The site has more herb layer than the tree layer. Species such as Solanum mariantanum, Melinis repens, Momordica balsamina, and Acacia tortilis were recorded.
Picture 4: DL 2 – drainage line to the Brak River
22 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Site Site Description and observation
The site/point is located south-west of the Brak River and the flow is to the east. The site is not different from DL 2, because it does not have water flowing as it is a non-perennial drainage line. No signs of erosion were recorded Terrestrial species such as Ipomea spp., Sida cordofolia, Sporobolus spp., were recorded.
Picture 5: DL 3 – Drainage line of the Brak River
23 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Site Site Description and observation
No water was flowing during the survey The site is charachterised by grasses No sign of erosion was observed The drainage line flows to the northern direction until it feeds to the Brak River
Picture 6: Point DL 4
24 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Site Site Description and observation
The point is located on a non-perennial drainage line that feed the Brak River The site is dominated by grasses such as Eragrostis curvula, Melinis repens, Urochloa mosambicens No water flow was encountered
Picture 7: DL 5 point
25 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
5. Impact Assessment and mitigation measures
A development has several impacts on the surrounding environment and particularly on a riparian area. The development changes habitats, the ecological environment, infiltration rates, amount of runoff and runoff intensity of stormwater, and therefore the hydrological regime of the site. A range of management measures are available to address threats posed to watercourses. In the context of the proposed development, the mitigation measures proposed below are intended to prevent further degradation to the riparian area as a result of the construction and operation. It is important to note that this section aims to highlight areas of concern. The details of the mitigation measures that are finally put in place should ideally be based on these issues, but must necessarily take into consideration the physical and economic feasibility of mitigation. It is important that any mitigation be implemented in the context of an Environmental Management Plan in order to ensure accountability and ultimately the success of the mitigation.
5.1. Methodology in determine significance
The potential environmental impacts of the proposed project were evaluated according to their severity, duration, extent and significance of the impact, and include the cumulative impact. The Risk Assessment Methodology was used for the ranking of the impacts. This system derives environmental significance on the basis of the consequence of the impact on the environment and the likelihood of the impact occurring.
5.1.1. Consequence
Consequence is calculated as the average of the sum of the ratings of severity, duration and extent of the environmental impact. Likelihood considers the frequency of the activity together with the probability of an environmental impact occurring. The following tables (Table 4 to Table 11) describe the process in detail:
Table 4: Assessment and Rating of Severity
Rating Description
1 Negligible / non-harmful / minimal deterioration (0 – 20%)
2 Minor / potentially harmful / measurable deterioration (20 – 40%)
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
3 Moderate / harmful / moderate deterioration (40 – 60%)
4 Significant / very harmful / substantial deterioration (60 – 80%)
5 Irreversible / permanent / death (80 – 100%)
Table 5: Assessment and Rating of Duration
Rating Description
1 Less than 1 month / quickly reversible
2 Less than 1 year / quickly reversible
3 More than 1 year / reversible over time
4 More than 10 years / reversible over time / life of project or facility
5 Beyond life of project of facility / permanent
Table 6: Assessment and Rating of Extent
Rating Description
1 Within immediate area of activity
2 Surrounding area within project boundary
3 Beyond project boundary
4 Regional / provincial
5 National / international
Consequence is calculated as the average of the sum of the ratings of severity, duration and extent of the environmental impact.
27 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Table 7: Determination of Consequence
Determination of Consequence (C) (Severity + Duration + Extent) / 3
5.1.2. Likelihood
Likelihood considers the frequency of the activity together with the probability of the environmental impact associated with that activity occurring.
Table 8: Assessment and Rating of Frequency
Rating Description
1 Less than once a year
2 Once in a year
3 Quarterly
4 Weekly
5 Daily
Table 9: Assessment and Rating of Probability
Rating Description
1 Almost impossible
2 Unlikely
3 Probable
4 Highly likely
5 Definite
28 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Table 10: Determination of Likelihood
Determination of Likelihood (L) = (Frequency + Probability) / 2
5.1.3. Environmental Significance
Environmental significance is the product of the consequence and likelihood values.
Table 11: Determination of Environmental Significance
Environmental Significance (Impact) = C × L Description
L (1 – 4.9) Low environmental significance
LM (5 – 9.9) Low to medium environmental significance
M (10 – 14.99) Medium environmental significance
MH (15 – 19.9) Medium to high environmental significance
H (20 – 25) High environmental significance. Likely to be a fatal flaw.
5.2. Impact assessment
The potential possible impacts identified for both construction and operational phases and their management/mitigation measures associated with the construction and operation of the Berenice Colliery are outlined in table 12 and 13 below.
5.2.1. Construction phase
Construction activities such as vegetation clearance could cause erosion which will lead to high volumes of sediment entering streams. Also, hydrocarbon (oil, petrol and diesel) spills and/or leakages from construction vehicles and/or equipment could result in secondary contamination of the surface water should they occur simultaneously with a heavy rainfall event. This could lead to:
29 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Changing the quantity and fluctuation properties of the watercourse; Changing the amount of sediment entering water resource and associated change in turbidity (increasing or decreasing the amount); Alteration of water quality – increasing the amounts of nutrients and toxins; and Changing the physical structure within a water resource (habitat).
30 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Severity Duration Extent Consequence Frequency Probability Likelihood Status Significance
With no 4 3 3 3.3 5 4 4.5 Negative 14.9 (M) mitigation
Mitigation measures:
Centralize the mine layout to affect as few surface watercourses as possible. Capture and contain all dirty water from the construction operations. Management of on-site water use and prevent stormwater or contaminated water directly entering the watercourse (thus treat and reuse dirty water within construction activities). Treat all surplus dirty water. Consider this water for treatment and discharge to receiving streams, or to third party users. Given the sensitive nature of the receiving watercourses and the potentially far reaching effects within the River system, these recommendations should be coupled with the requirements of GN704. If possible construction should preferably take place during the dry season. All construction vehicles should be kept in good working condition to avoid. All construction vehicles should be parked in demarcated areas when not in use and drip trays should be placed under vehicles to collect any spillages/ leaks. Formalise access roads and make use of existing roads and tracks where feasible, rather than creating new routes through naturally vegetated areas. Monitor rehabilitation and the occurrence of erosion twice during the rainy season for at least two years and take immediate corrective action where needed. Monitor the establishment of alien invasive species within the areas affected by the construction and maintenance of the proposed infrastructure and take
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
immediate corrective action where invasive species are observed to establish. During the construction phase, measures must be put in place to control the flow of excess water so that it does not impact on the surface vegetation. Protect all areas susceptible to erosion and ensure that there is no undue soil erosion resultant from activities within and adjacent to the construction camp and work areas. Demarcate the riparian areas and buffer zones to limit disturbance, clearly mark these areas as no-go areas. Provision of adequate sanitation facilities located outside of the riparian area or its associated buffer zone. Establishment of buffer zones to reduce nutrient inputs in diffuse flow Implementation of appropriate stormwater management measures around the excavation to prevent the ingress of run-off into the excavation. Any activities within 50m of riparian areas are subject to authorization by means of a water use license. Construction in and around watercourses must be restricted to the dryer winter months where responsible. A temporary fence or demarcation must be erected around the works area to prevent access to sensitive environs. The works areas generally include the servitude, construction camps, areas where material is stored and the actual footprint of the infrastructure Planning of the construction site must include eventual rehabilitation / restoration of indigenous vegetative cover Have oil/diesel spill kits on site. Confirm surface water monitoring protocol and plans. Recommended that surface water monitoring be undertaken on a quarterly basis.
With Mitigation 3 3 2 2.7 5 3 4 Negative 10.8 (Medium)
Significance of the impact:
The significance of this impact is regarded as medium without mitigation, however, if the above mitigation measures are implemented successfully, the significance will remain the same but the magnitude of the impact will be minimised.
32 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
5.2.2. Operational phase
Hydrocarbon (oil, petrol and diesel) spills and/or leakages could occur from vehicles and/or equipment. These spills could contaminate the surface and ground water should they occur simultaneously with a heavy rainfall event.
Operational activities such as the establishment of increased hard surfaces could cause erosion which will lead to high volumes of sediment entering streams. This could again lead to increased silt loads entering the water bodies, especially under flood conditions (decreasing storage capacity). The mine’s pollution control dams also pose a risk of contamination of surface water during flood events.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Severity Duration Extent Consequence Frequency Probability Likelihood Status Significance
With no 4 4 3 3.7 2 4 3 Negative 11.1 (M) mitigation
Mitigation Measures
Centralise the mine layout to affect as few surface watercourses as possible, and ideally only one;
Capture and contain all dirty water from the operations activities;
Treat and reuse dirty water within construction activities;
Treat as a water resource all surplus dirty water. Consider this water for treatment and discharge to receiving streams, or to third party users;
All operational vehicles should be kept in good working condition, and should be parked in demarcated areas when not in use and drip trays should be placed under vehicles to collect any spillages/ leaks.
Keep dirty areas like stockpiles, workshops and oil and diesel storage areas as small as possible; and
Contain poor quality runoff from dirty areas and divert this water to pollution control dam for re-use.
Have oil/diesel spill kits on site.
Confirm surface water monitoring protocol and plans. Recommended that monitoring be conducted on a quarterly basis.
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Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
Where possible, maintenance within watercourses must be restricted to the drier winter months. Maintenance activities should not impact on rehabilitated areas and where soil or vegetation disturbances took place, this should be rehabilitated immediately.
With Mitigation 3 4 1 2.7 2 3 2.5 Negative 6.8 (LM)
Significance of the impact
The significance of this impact is regarded as medium without mitigation, however, if the above mitigation measures are implemented successfully, the significance will be reduced to low medium.
35 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
6. Conclusion and recommendations
Due to the lack of water flow during the assessment period the SASS5 protocol was not used to determine the overall ecological status of the sites. All sites were assessed and evaluated in terms of their surrounding habitat and possible impacts to the aquatic ecosystem.
All proposed mitigation measures should be adhered to during both construction and operation phases to ensure the watercourses condition does not deteriorate any further.
The following recommendations were made:
Construct erosion control measures (rip rap, silt trap, gabions, etc.) especially at the stream banks as well as the inlet and outlet of the culverts; Implement a weed control measures within the stream during construction and maintain the riparian zone at low to no invasion levels through regular weed control follow-ups; Rehabilitation of disturbed area must be undertaken concurrently with construction activities; It is also recommended that construction be undertaken during dry season.
36 Brak River stream profiling study for the proposed Berenice Colliery in Limpopo Province
7. REFERENCES 1. Dalls, H. F. (2007).River Health Programmes: South African Scoring System (SASS) Data Interpretation Guidelines. Institute of Natural Resources. Cape Town: Department of Water Affairs and Forestry 2. Department of Water Affairs and Forestry (1996). South African Water Quality Guidelines: volume 7: Aquatic Ecosystem. Department of Water Affairs and Forestry, Pretoria 3. Department of Water Affairs and Forestry (DWAF) second edition 1996. South African Water Quality Guidelines Volume 8: Field Guide. Pretoria. 4. Department of Water Affairs and Forestry (DWAF) 2001. River Health Programme: [Online] Available at: http://www.dwa.gov.za/iwqs/rhp/state_of_rivers/letluv_01_toc.html. 5. Kleynhans, C. J., & Louw, M. D. (2007). Module A: EcoClassification and EcoStatus determination in River EcoClassification: Manual for EcoStatus Determination (version 2). Water Research Commission, Department of Water Affairs. Pretoria: WRC Report No. TT 329/08. 6. McMillan, P. H. (1998). An integrated habitat assessment system (IHAS version 2) for the rapid biological assessment of rivers and streams. Council for Scientific and Industrial Research, Water Resources Management Programme. Pretoria: CSIR Report No. ENV-P-I 98132. 7. Odum, E. P. (1971). Fundamental of Ecology. Third Edition. W. B. Saunders Co. London. 8. Ollis, D.J., Boucher, C., Dallas, H.F. & Esler, K.J. 2006. Preliminary testing of the Integrated Habitat Assessment System (IHAS) for aquatic macro-invertebrates. African Journal of Aquatic Science, 31(1) 1-14. 9. Roux D. J. (1999). Integrating stressor and response monitoring into a Resource-Based Water Quality Assessment Framework. Environmental Management 23(1) 15-30.
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