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17/2/3/GS-59
Draft Environmental Impact Report for the Secunda Growth
Programme (SGP) 1B (New): Proposed Retrofitting of Two Gas
Turbines, Mpumalanga
December 2012 A Project for: Sasol Synfuels (Pty) Ltd
Tel: +27 (0) 12 367 5973 Email:[email protected] Fountain
Square, 78 Kalkoen Street, Monument Park Ext. 2, Pretoria, 0181
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DOCUMENT DESCRIPTION
Client: Sasol Synfuels (Pty) Ltd Project Name: Draft
Environmental Impact Report for the Proposed Retroffiting of Two
Gas Turbines, Secunda SSI Environmental Reference Number:
E02.PTA.000407 Authority Reference: 17/2/3/GS-59 Compiled by:
Phyllis Kalele Date: December 2012 Location: Pretoria Reviewer:
Prashika Reddy
_____________________________ Signature
Approval: Prashika Reddy ______________________________
Signature
© SSI Environmental All rights reserved No part of this
publication may be reproduced or transmitted in any form or by any
means, electronic or mechanical, without the written permission
from SSI Environmental.
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TABLE OF CONTENTS
1 INTRODUCTION 1 1.1
NEED AND BACKGROUND 1 1.2
APPROACH TO THE EIA STUDIES
2 1.2.1 ENVIRONMENTAL SCOPING STUDY
2 1.2.2 ENVIRONMENTAL IMPACT STUDY
2 1.3
DETAILS OF THE ENVIRONMENTAL ASSESSMENT PRACTITIONER
3 1.4 STRUCTURE OF THE REPORT
4
2 PROJECT DESCRIPTION 5 2.1
PROJECT LOCATION 5 2.2
ELECTRICITY GENERATION FROM AROMATIC NAPHTHA
7 2.3
FACILITIES FOR RETROFITTING THE GAS TURBINES
8
3 PROJECT ALTERNATIVES 11 3.1
SITE ALTERNATIVES – AROMATIC NAPHTHA TANK
11 3.1.1 SITE 1 (PREFERRED)
11 3.1.2 SITE 2 (ALTERNATIVE 1)
11 3.2 NO‐GO ALTERNATIVE 11
4
GENERAL DESCRIPTION OF THE STUDY AREA
12 4.1 GEOLOGY 12 4.2
TOPOGRAPHY AND SOILS 12 4.3
WATER RESOURCES 12 4.3.1
GEOHYDROLOGY (GROUNDWATER) 12 4.3.2
HYDROLOGY (SURFACE WATER) 12 4.4
CLIMATE AND LOCAL WEATHER CONDITIONS
13 4.4.1 WIND 13 4.4.2
ATMOSPHERIC STABILITY 15 4.4.3
TEMPERATURE AND HUMIDITY 16 4.4.4
PRECIPITATION 17 4.5 AIR QUALITY
18 4.5.1 IDENTIFIED SENSITIVE RECEPTORS
18 4.5.2
EXISTING SOURCES OF AIR POLLUTION
18 4.5.3 AGRICULTURE 19 4.5.4
DOMESTIC FUEL BURNING 19 4.5.5
MINING ACTIVITIES 20 4.5.6
VELD FIRES 20 4.5.7 POWER STATIONS
21 4.5.8 OTHER SASOL OPERATIONS
21 4.5.9 AIR QUALITY SITUATION
21 4.6 NOISE 30 4.7 SOCIAL
30 4.8 LAND‐USE 30 4.9
HEALTH AND SAFETY 30 4.10 HERITAGE
30
5
ENVIRONMENTAL IMPACT ASSESSMENT METHODOLOGY AND APPROACH
31 5.1
APPROACH TO UNDERTAKING THE STUDY
31
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5.2 ENVIRONMENTAL SCOPING STUDY
31 5.3 AUTHORITY CONSULTATION
31 5.3.1
CONSULTATION WITH DECISION‐MAKING AUTHORITY
31 5.3.2 ENVIRONMENTAL IMPACT ASSESSMENT
31 5.3.3
METHODOLOGY – ASSESSMENT OF IMPACTS
32 5.3.4 IMPACT ASSESSMENT METHODOLOGY
32 5.4 EIA REPORT (EIR)
34 5.5
DRAFT ENVIRONMENTAL MANAGEMENT PROGRAMME
35 5.6 SPECIALIST STUDIES 35 5.7
ASSUMPTIONS AND LIMITATIONS 35
6 PUBLIC PARTICIPATION PROCESS
37 6.1
AIMS OF THE PUBLIC PARTICIPATION PROCESS
37 6.1.1
CONSULTATION WITH RELEVANT AUTHORITIES AND KEY STAKEHOLDERS
37 6.1.2 ADVERTISING 38 6.1.3
IDENTIFICATION OF INTERESTED AND AFFECTED PARTIES
38 6.1.4 I&AP DATABASE
38 6.1.5 ISSUES TRAIL 38 6.1.6
PUBLIC REVIEW OF THE DRAFT ENVIRONMENTAL IMPACT REPORT
39 6.1.7
AUTHORITY REVIEW OF THE DRAFT ENVIRONMENTAL IMPACT REPORT
39 6.1.8 ENVIRONMENTAL AUTHORISATION
39
7
POTENTIAL IMPACTS ASSOCIATED WITH THE PROJECT
40 7.1
CONSTRUCTION PHASE IMPACTS ‐ AROMATIC NAPHTHA TANK
40 7.1.1 GEOLOGY 40 7.1.2 SOILS
40 7.1.3 WATER RESOURCES 42 7.1.4
DUST AND EMISSIONS DURING CONSTRUCTION
43 7.1.5 NOISE 44 7.1.6 WASTE
45 7.1.7 HEALTH AND SAFETY
46 7.1.8 SOCIAL 47 7.2
CONSTRUCTION PHASE IMPACTS – ADDITIONAL INFRASTRUCTURE
48 7.3
OPERATIONAL PHASE IMPACTS ‐ AROMATIC NAPHTHA TANK
51 7.3.1 SOILS 51 7.3.2
GEOHYDROLOGY (GROUNDWATER) AND HYDROLOGY (SURFACE WATER)
52 7.3.3 AIR QUALITY ‐ EMISSIONS
53 7.3.4 WASTE 54 7.3.5 SAFETY
55 7.4
OPERATIONAL PHASE IMPACTS – ADDITIONAL INFRASTRUCTURE (
56 7.5 CUMULATIVE IMPACTS 59 7.5.1
EMISSIONS 60 7.6 DECOMMISSIONING PHASE
60
8 CONCLUSIONS AND RECOMMENDATIONS
61 8.1 CONCLUDING REMARKS 61 8.2
FINAL RECOMMENDATIONS 62
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TABLE OF FIGURES
FIGURE 1: ENVIRONMENTAL STUDIES FLOWCHART
3
FIGURE 2: LOCATION OF THE AROMATIC NAPHTHA, MFO, CETANE & OCTANE TANKS AND FLARE
6 FIGURE 3: EXAMPLE OF AN ENCLOSED GROUND FLARE (COURTESY: JOHN ZINK®)
9 FIGURE 4: EXAMPLE OF AN ELEVATED FLARE (COURTESY: JOHN ZINK®)
10 FIGURE 5: PERIOD WIND ROSE FOR SASOL CLUB & LANGVERWACHT STATIONS (JAN 2006 – DEC 2010)
14 FIGURE 6: DIURNAL WIND ROSES FOR SASOL CLUB & LANGVERWACHT STATIONS (JAN 2006 – DEC 2010) 14 FIGURE 7: SEASONAL WIND ROSES FOR SASOL CLUB & LANGVERWACHT STATIONS JAN 2006 – DEC 2010 15 FIGURE 8: STABILITY CLASS FREQUENCY DISTRIBUTION FOR SASOL CLUB & LANGERWACHT STATIONS
16 FIGURE 9: AVERAGE MONTHLY TEMPERATURE & HUMIDITY FOR SASOL CLUB & LANGVERWACHT (JAN 2006
– DEC 2010)
17 FIGURE 10: ANNUAL AVERAGE BENZENE CONCENTRATION (PPB) RECORDED AT TWO SASOL STATIONS
22 FIGURE 11: DAILY AVERAGE PM10 CONCENTRATIONS RECORDED AT THE SASOL STATIONS
23 FIGURE 12: DAILY AVERAGE PM10 CONCENTRATIONS RECORDED AT THE DEA STATION
24 FIGURE 13: DIURNAL PM10 CONCENTRATIONS RECORDED AT THE SASOL STATIONS
24 FIGURE 14: HOURLY AVERAGE NO2 CONCENTRATIONS RECORDED AT THE SASOL STATIONS (JAN – DEC 2009)
25 FIGURE 15: HOURLY AVERAGE NO2 CONCENTRATIONS
(PPB) RECORDED AT THE DEA STATION
(JAN – DEC
2009)
26 FIGURE 16: DIURNAL NO2 CONCENTRATIONS (PPB) RECORDED AT THE SASOL STATIONS
27
LIST OF TABLES
TABLE 1: DETAILS OF THE EAP
3
TABLE 2: REPORT STRUCTURE
4 TABLE 3: COORDINATES OF THE DIFFERENT COMPONENTS OF THE PROPOSED PROJECT
5 TABLE 4: ATMOSPHERIC STABILITY CLASSES (PASQUILL GIFFORD)
15 TABLE 5: IDENTIFIED SENSITIVE RECEPTORS SURROUNDING THE SITE
18 TABLE 6: ANNUAL AVERAGE BENZENE (PPB) CONCENTRATIONS FOR ALL MONITORING STATIONS FOR THE
PERIOD 2006 – 2010
22 TABLE 7: MAXIMUM HOURLY, DAILY AND ANNUAL AVERAGE PM10, SO2 AND NO2 CONCENTRATIONS FOR
ALL MONITORING STATIONS FOR THE PERIOD 2006 – 2010
28 TABLE 8: ANNUAL AVERAGE PM10, SO2 AND NO2 CONCENTRATIONS FOR ALL MONITORING STATIONS FOR
THE PERIOD 2006 – 2010
29 TABLE 9: EXCEEDANCES OF THE
NATIONAL STANDARDS (WHERE APPLICABLE)
AT ALL MONITORING
STATIONS FOR THE PERIOD 2006 – 2010
29 TABLE 10: CRITERIA FOR THE RATING OF IMPACTS
33 TABLE 11: CRITERIA FOR THE RATING OF CLASSIFIED IMPACTS
34 TABLE 12: KEY STAKEHOLDERS CONTACTED AS PART OF PP PROCESS
37 TABLE 13: SUMMARY OF CONSTRUCTION PHASE IMPACTS
48 TABLE 14: SUMMARY OF OPERATIONAL PHASE IMPACTS
56
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APPENDICES APPENDIX A: LOCALITY MAP
APPENDIX B: PROCESS FLOW DIAGRAM APPENDIX C: PROPERTIES OF AROMATIC NAPHTHA APPENDIX D: APPROVAL OF SCOPING STUDY APPENDIX E: AIR QUALITY IMPACT ASSESSMENT APPENDIX F: PUBLIC NOTIFICATIONS APPENDIX G: I&AP DATABASE AND ISSUES TRAIL APPENDIX H: ENVIRONMENTAL MANAGEMENT PROGRAMME
ACRONYMS CCR Continuous Catalyst Regeneration (part of the
Platforming units) CO Carbon monoxide CTN Coal Tar Naphtha DHT
Distillate Hydrotreater DSC Distillate Selective Cracker H2S
Hydrogen sulphide EAP Environmental Assessment Practitioner EIA
Environmental Impact Assessment EMPr Environmental Management
Programme ESS Environmental Scoping Study ESR Environmental Scoping
Report I&AP Interested and Affected Party MDEDET Mpumalanga
Department of Economic Development, Environment and Tourism MFO
Medium Fuel Oil NEMA National Environmental Management Act NHT
Naphtha Hydrotreater NO Nitrogen monoxide NO2 Nitrogen dioxide O3
Ozone PHT Poly Hydrotreater RON Research Octane Number SCC Synfuels
Catalytic Cracker SCF2 Secunda Clean Fuels 2 SGP Secunda Growth
Programme SO2 Sulphur dioxide TAME Tertiary Amyl Methyl Ether
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1 INTRODUCTION Due to the new fuel specifications, Sasol
Technology proposes the retrofitting of two existing gas turbines
as the basis for the Secunda Growth Programme (SGP) 1B (new)
project (also referred to as Secunda Clean Fuels (SCF2) project.
The turbines will be retrofitted for co-firing using aromatic
naphtha and gas simultaneously, as these were originally designed
only for gas firing. Currently 100 MW of electricity (per turbine)
is generated in a closed cycle system in the turbines and it should
be noted there will be no change in the amount of electricity
generated. Aromatic naphtha is the liquid fuel hydrocarbon stream
that contains approximately 40% benzene. The sources of the
aromatic naphtha streams are the Synfuels Catalytic Cracker (Unit
293) gasoline and the Coal Tar Naphtha (CTN) Hydrogenation units
(Units 15 and 215). Each of these stream sources will be sent to
separate fractionators to obtain a benzene-rich stream which will
be combusted in the gas turbines to generate electricity. In
support of the retrofitting of the two gas turbines, Sasol Synfuels
therefore proposes to install: i. A hold up tank with a capacity of
approximately 11500 m3 to store aromatic naphtha. The hold up tank
will be
located in the Eastern tank farm. ii. A Medium Fuel Oil (MFO)
tank with a capacity of approximately 2000 m3 in the Western tank
farm. iii. A tank with a capacity of approximately 6000 m3 for the
Octane booster system in the Western tank farm. iv. A tank with a
capacity of approximately 100 m3 tank for the Cetane booster system
in the Western tank farm.
After the Environmental Scoping Study was concluded and
subsequently accepted by the Mpumalanga Department of Economic
Development, Environment and Tourism (MDEDET) on 07 February 2012,
the Sasol engineering team indicated that the liquid feed systems
required on the gas turbines, to enable electricity generation,
will require protection systems on the process equipment. The
Pressure Safety Systems will need to be routed to a safe
location/system. It was originally proposed that a vapour line from
the liquid knock-out system will be routed to the existing LP flare
header. Routing this vapour to this destination requires
significant civil work (foundations) and a new pipe rack to be
installed for an ad hoc vapour flow from the safety systems.
Routing such a line to the LP Flare header would hinder access (for
cranes during turnarounds) to various units in the vicinity and
therefore is not deemed suitable or practical to deal with relief
loads. Therefore, it was proposed to install a flare on the Closed
Cycle Power Generation Plant (Unit 543) (already authorised MDEDET
Ref. No. 17/2/22/3/GS 2) plot plan to handle the ad hoc vapours
flows, due to emergency conditions, from the liquid hydrocarbon
feed system. This would protect the unit and maintain its safety
integrity. The flare will require pilots to be lit to ensure that
it is available at all times, the fuelling gas to keep these pilots
lit is likely to be natural gas (NG) and/or Methane Rich Gas (MRG).
It should be noted that no new listed activities in terms of the
Environmental Impact Assessment Regulations (2012) GN R 544 – 546
will be triggered by the addition of the flare. The proposed
project is situated within the Sasol Industrial Complex in Secunda
(refer to Appendix A for the locality map).
1.1 Need and Background The purpose of the SGP 1B (new) project
is to achieve compliance with the clean fuel specifications (Euro V
specifications effective, 01 July 2017)) which were published in
Government Notice R.421 of 31 May 2012. According to the Euro V
specifications, South Africa has to comply with international best
practice and specify the content of benzene in fuel. For the Petrol
pool, the intent is to reduce the benzene content in fuel from 3
volume% to a maximum of 1 volume% and achieve the 18 volume%
olefins specifications, while for the Distillate pool the T95
specification of 360 °C is to be met. The 1 volume% benzene content
of the fuel pool will be met by generating electricity from the
aromatic naphtha stream. The 18 volume% olefin specification will
be met within the existing operational parameters of the Synfuels
complex. The future T95 specification will be met by fractionation
optimisation and minor modifications of the existing Distillate
Hydrotreaters and the Distillate Selective Cracker.
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To ensure compliance with the EIA regulations (2010) made under
section 24 (5) of the National Environmental Management Act - NEMA
(Act No. 107 of 1998) (as amended) and environmental best practice,
Sasol Synfuels (Pty) Ltd appointed SSI Environmental as the
independent Environmental Assessment Practitioner (EAP) to conduct
the necessary studies to obtain Environmental Authorisation to
undertake the proposed project. It should be noted, that the
retrofitting of the gas turbines is not the trigger for the EIA but
rather the construction of the various tanks mentioned in points i
– iv as the installation of the gas turbines and generation of
electricity was authorised as part of the Power Generation from
Waste Energy project (MDEDET Ref. No. 17/2/22/3/GS 2).
1.2 Approach to the EIA Studies The environmental impacts
associated with the proposed project require investigation in
compliance with the Environmental Impact Assessment Regulations
(2010) published in Government Notice No. R. 543 and No. R. 545 and
read with Section 24 (5) of the National Environmental Management
Act (NEMA-Act No 107 of 1998) (as amended). The required
environmental studies include the undertaking of an Environmental
Impact Assessment (EIA) process. This process is being undertaken
in two phases: Phase 1 - Environmental Scoping Study (ESS)
including Plan of Study for EIA - complete; and Phase 2 -
Environmental Impact Assessment (EIA) and Environmental Management
Programme (EMPr).
1.2.1 Environmental Scoping Study The ESS provided a description
of the receiving environment and how the environment may be
affected by the development of the proposed project. Desktop
studies making use of existing information were used to highlight
and assist in the identification of potential significant impacts
(both social and biophysical) associated with the proposed project.
Additional issues for consideration were extracted from feedback
from the public participation process, which commenced at the
beginning of the Scoping phase, and will continue throughout the
duration of the project. All issues identified during this Scoping
study were documented within the final Environmental Scoping Report
(ESR) which was accepted by the MDEDET on 07 February 2012.
1.2.2 Environmental Impact Study The Environmental Impact
Assessment phase will aim to achieve the following: to provide an
overall assessment of the social and biophysical environments of
the affected area by the
proposed project; to undertake a detailed assessment of the
preferred site/alternatives in terms of environmental criteria
including the rating of significant impacts; to identify and
recommend appropriate mitigation measures (to be included in an
EMPr) for potentially
significant environmental impacts; and to undertake a fully
inclusive public participation process to ensure that I&AP
issues and concerns are
recorded and commented on and addressed in the EIA process.
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FIGURE 1: ENVIRONMENTAL STUDIES FLOWCHART
1.3 Details of the Environmental Assessment Practitioner SSI
Environmental has been appointed as the independent Environmental
Assessment Practitioner (EAP) by Sasol Synfuels, to undertake the
appropriate environmental studies for this proposed project. The
professional team of SSI Environmental has considerable experience
in the environmental management and EIA fields. SSI Environmental
has been involved in and/or managed several of the largest
Environmental Impact Assessments undertaken in South Africa to
date. A specialist area of focus is on assessment of multi-faceted
projects, including the establishment of linear developments
(national and provincial roads, and power lines), bulk
infrastructure and supply (e.g. wastewater treatment works,
pipelines, landfills), electricity generation and transmission, the
mining industry, urban, rural and township developments,
environmental aspects of Local Integrated Development Plans
(LIDPs), as well as general environmental planning, development and
management.
TABLE 1: DETAILS OF THE EAP CONSULTANT: SSI ENVIRONMENTAL
Contact Persons: Prashika Reddy and Phyllis Kalele Postal Address
PO Box 25302, Monument Park, 0105 Telephone: 012 367 5973 / 5916
Facsimile: 012 367 5878 E-mail: [email protected] /
[email protected] Expertise: Prashika Reddy is a senior
environmental scientist / associate
(BSc Honours – Geography) with experience in various
environmental fields including: environmental impact assessments,
environmental management programmes, public participation and
environmental monitoring and auditing. Ms Reddy has extensive
experience in compiling environmental reports (Screening, Scoping,
EIA and Status Quo Reports). She is a registered Professional
Natural Scientist (Pr Sci Nat 400133/10) with the South African
Council for Natural Scientific Professions (SACNASP). Phyllis
Kalele is a senior environmental consultant with experience in
various facets of environmental management. These include
conducting the Public Participation process; compiling
Environmental Impact Reports; compiling Environmental Management
Programmes; conducting environmental awareness training; and
conducting legal compliance audits. She is a registered
Professional Natural
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CONSULTANT: SSI ENVIRONMENTAL Scientist (Pr Sci Nat 400456/11)
with SACNASP.
1.4 Structure of the Report
TABLE 2: REPORT STRUCTURE CHAPTER CONTENT
Chapter 1 – Introduction Introduction to project Chapter 2 -
Project Description Provides the technical description of the
project as well as a
description of the infrastructure Chapter 3 - Project
Alternatives Consideration of alternatives (design/layout, site and
do-nothing)
for the project Chapter 4 - General Description of the Study
Area
A description of the biophysical and social environment
Chapter 5 – Environmental Impact Assessment Methodology and
Approach
Methodology used in the assessment of significant impacts
Chapter 6 - Public Participation Process Overview of the public
participation process conducted to date Chapter 7 – Potential
Impacts associated with the Project
A description and assessment of construction, operations,
decommissioning and cumulative impacts
Chapter 8 - Conclusions and Recommendations
Conclusions and recommendations of the Environmental Impact
Assessment Study
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2 PROJECT DESCRIPTION
2.1 Project Location The project will take place within the
primary area of the Sasol Secunda Complex. The tanks proposed to be
constructed will be located in the areas as shown in Figure 2
below. The coordinates of the different components of the project
are shown in Table 3 below.
TABLE 3: COORDINATES OF THE DIFFERENT COMPONENTS OF THE PROPOSED
PROJECT PROPOSED ACTIVITY COORDINATES
New Aromatic Naphtha Tank (Eastern Tank Farm) -Preferred
site
26°32'49.14"S; 29°10'1.90"E
New Aromatic Naphtha Tank (Western Tank Farm) -Alternative
site
26°32'37.45"S; 29°9'18.49"E
New MFO Tank (Western Tank Farm) 26°32'49.62"S;
29°8'57.98"E Modifications to the existing Refinery Plants
(East) 26°33'8.23"S; 29°10'9.41"E Modifications to the
existing Gas Turbines 26°33'55.63"S; 29°9'53.15"E Octane
Booster tanks (Western Tank Farm) 26°32'37.45"S; 29°9'18.49"E
Cetane Booster tanks (Western Tank Farm) 26°32’39.20”S;
29°9’11.74”E Flare 26°33’50.6”S; 29°09’56.8”E
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FIGURE 2: LOCATION OF THE AROMATIC NAPHTHA, MFO, CETANE &
OCTANE TANKS AND FLARE (Courtesy Google Earth, 2010)
Western Tank Farm
Eastern Tank Farm
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2.2 Electricity Generation from Aromatic Naphtha Aromatic
naphtha is the liquid fuel stream and it contains an average
concentration of approximately 40% benzene. The sources of the
aromatic naphtha streams are the Synfuels Catalytic Cracker - SCC
(Unit 293), gasoline and the Coal Tar Naphtha (CTN) Hydrogenation
units (Units 15 and 215). Each of these stream sources will be sent
to separate fractionators1 to obtain a benzene-rich stream which
will be combusted in the gas turbines to generate electricity. At
Units 15 and 215 (CTN Hydrogenation units), new CTN fractionation
columns will be installed to remove benzene from the CTN. The CTN
aromatic naphtha (with benzene content of approximately 40wt%) will
be recovered in the CTN fractionator overhead stream and pumped to
the hold up aromatic naphtha storage tank. The CTN fractionation
bottoms will be routed to the existing Naphtha Hydrotreatment (NHT)
feed tanks. SCC aromatic naphtha is prone to gum formation and will
be dosed with an additive to prevent gumming. This stream will be
routed to an intermediate storage tank (256TK-1509) prior to being
routed to the gas turbines. This will ensure that gas turbines
receive a stable feed to minimise interruptions to power generation
at Unit 543. The SCC aromatic naphtha and CTN aromatic naphtha are
both fed to the Closed Cycle Power Generation Plant - Unit 543, via
tanks, where it will be combusted in the gas turbines (to be
retrofitted) for the purpose of electricity generation. At the NHT
units (Units 30 and 230), new Dehexanizer columns will be installed
to recover benzene precursors as an overhead product that will be
routed to low octane fuel component tanks (256TK-3201/2) as a
petrol blending component. Both 256TK-3201 and 256TK-3202 are
currently in CTN service and the impact due to a change of service
will be investigated. Dehexanizer overheads can also be routed to
the gas turbines at Unit 543 should the need arise, typically
during upset scenarios. Benzene, having a RON of 101, is
contributing significantly to Secunda’s octane pool. Once the
benzene content is reduced to 1 volume%, it will become
increasingly difficult to meet the unleaded petrol (ULP) 93 RON
target during upset conditions. In order to improve the petrol
pool’s RON, it is proposed to implement side-draw streams on the
Poly Hydrotreatment (PHT) splitters at both Units 33 and 233
(33/233VL-101). Despite the proposed efforts to improve the petrol
pool’s RON, there is still a significant risk of a RON deficit
during upset scenarios such as when the Tertiary Amyl Methyl Ether
(TAME) block and SCC are offline. It was therefore proposed to make
use of a chemical fuel additive to ensure that the RON target be
met at all times. ChimecFA0612 was identified as the additive of
choice. New offloading, storage and dosing facilities will be
required to introduce this additive into the fuel pool. The Diesel
Hydrotreater units (Unit 35 DHT and Unit 235 DHT) are the final
processing step for distillate streams of the diesel value chain
for the factory. Unit 35 is divided into the Distillate
Hydrotreater (DHT) and the Distillate Selective Cracker (DSC). The
DHT fractionation system produces naphtha, light diesel and a heavy
stream. This heavy stream is the feed to the DSC unit. The DSC unit
produces a naphtha stream, a heavy diesel and a Medium Fuel Oil
(MFO). In order to meet the T95 diesel specification, the post SGP
1B (new) operation of the DSC fractionators will result in a higher
yield of MFO. It is expected that the MFO production will increase
from 4.0 m3/h to 12.8 m3/h. As a result, the MFO slate will also
become lighter. To accommodate the expected increase in MFO
production, additional storage (in the form of a new 2000 m3 tank
in the Western tank farm) will be required. The process flow
diagram in Appendix B illustrates the process of generating
electricity from aromatic naphtha.
1 Fractionation is a separation process in which a certain
quantity of a mixture (solid, liquid, solute, suspension or
isotope) is divided up in a
number of smaller quantities (fractions) in which the
composition changes according to a gradient.
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2.3 Facilities for Retrofitting the Gas Turbines The proposed
retrofitting of the gas turbines will involve modifications in
various sections of the Secunda plant; these include:
i. West Refinery Plant The plant will be modified by:
Routing of aromatic naphtha into Unit 32 (Cat Poly). Upgrading
of side-draw on existing tower within Unit 33 (PHT). Installation
of a Dehexaniser with associated equipment at Unit 30 (NHT).
Modifications will be
required within the existing Unit 30 NHT, Platforming and
Continuous Catalyst Regeneration (CCR) units to process the
feedstocks to meet future fuel requirements.
Debottlenecking of the Medium Fuel Oil (MFO) product rundown
line in Unit 35 Distillate Selective Cracking (DSC).
Construction of a new CTN fractionation tower and associated
equipment in Unit 15 (Naphtha Hydrogenation) to generate a stream
of aromatic naphtha.
ii. Western Tank Farm (Unit 56) Installation of a steam heated
tank with a capacity of approximately 2000 m3 in Unit 56 for
MFO.
The tank will be a thermal insulated fixed roof storage tank.
Installation of an Octane booster system in Unit 56 which will be
comprised of an off-loading
facility, a tank with a capacity of approximately 6000 m3 and
blending pumps. The tank will be a thermal insulated fixed roof
storage tank.
Installation of a Cetane booster system in Unit 56 which will be
comprised of an off-loading facility, a tank with a capacity of
approximately 100 m3 and blending pumps. The tank will be a thermal
insulated fixed roof storage tank.
iii. Eastern Tank Farm (Unit 256) Installation of an
approximately 11500 m3 hold up tank in Unit 256 to store aromatic
naphtha. The
hold up tank will have a floating roof and the tank’s main role
will be the storage of aromatic naphtha.
iv. East Refinery Plant The plant will be modified by:
Upgrading of side-draw on the existing tower within Unit 233
(Polymer Hydrotreater). Installation of a Dehexaniser with
associated equipment in Unit 230 (Naphtha Hydrotreater).
Modifications will be required within the existing Unit 230 NHT,
Platforming and CCR units to process the feedstocks to meet future
fuel requirements.
Installation of a new charge heater in Unit 235 (Distillate
Hydrotreater) and other modifications to ensure unit can maintain
nameplate capacity with new fuel specification requirements.
Construction of a new CTN fractionation tower and associated
equipment in Unit 215 (Naphtha Hydrogenation) to generate a stream
of aromatic naphtha.
v. Closed Cycle Power Generation Units (Unit 543) The two
existing gas turbines in Unit 543 will be retrofitted in order to
utilise a liquid feed to
generate electricity.
vi. Handling of Relief Streams at the Gas Turbines using a Flare
The liquid feed systems required on the gas turbines, to enable
electricity generation, will require protection systems on the
process equipment. The pressure safety systems will need to be
routed to a safe location / system. It was originally proposed that
a vapour line from the liquid knock-out system will be routed to
the existing LP flare header. Routing this vapour to this
destination requires significant civil work (foundations) and a new
pipe rack to be installed for an ad hoc vapour flow from the safety
systems. Routing such a line to the LP Flare header would hinder
access (for cranes during turnarounds) to various units in the
vicinity and therefore is not deemed suitable or practical to deal
with relief loads. It is therefore proposed to install a flare –
either enclosed ground flare or an elevated flare (see example in
Figure 3 and Figure 4 ) on the U543 plot plan to handle the ad hoc
vapours flows, due to emergency conditions, from the liquid
hydrocarbon feed system. This would protect the unit and maintain
its safety
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integrity. The flare will require pilots to be lit to ensure
that it is available at all times; the fuelling gas to keep these
pilots lit is likely to be Natural Gas (NG) and/or Methane Rich Gas
(MRG).
The dimensions of the enclosed ground flare are 6.8 m diameter,
21 m total height and the plot space requirements is 20 x 20 m2.
The lined combustion chamber will be surrounded by a wind fence
(approximately 11.1 diameter) which also encloses the pilot and
burner manifolding. The wind fence would most probably be built out
of concrete blocks supported on concrete pillars. The preliminary
dimensions of an elevated flare are unknown at this stage therefore
only the enclosed ground flare will be included in the air quality
modelling, however, the impacts of both the ground and elevated
flare will be included in the Air Quality Impact Assessment
(AQIA).
FIGURE 3: EXAMPLE OF AN ENCLOSED GROUND FLARE (COURTESY: JOHN
ZINK®)2
2 http://www.johnzink.com
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FIGURE 4: EXAMPLE OF AN ELEVATED FLARE (COURTESY: JOHN
ZINK®)3
3 http://www.johnzink.com
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3 PROJECT ALTERNATIVES In terms of the EIA Regulations,
Section.28 (1) (c) feasible alternatives are required to be
considered as part of the environmental investigations. In
addition, the obligation that alternatives are investigated is also
a requirement of Section 24(4) of the National Environmental
Management Act (Act 107 of 1998) (as amended). An alternative in
relation to a proposed activity refers to the different means of
meeting the general purpose and requirements of the activity (as
defined in Government Notice R.543 of the EIA Regulations, 2010),
which may include alternatives to: a) the property on which or
location where it is proposed to undertake the activity; b) the
type of activity to be undertaken; c) the design or layout of the
activity; d) the technology to be used in the activity; e) the
operational aspects of the activity; and f) the option of not
implementing the activity. For this project, only feasible site
alternatives are applicable and are discussed in further detail in
the subsequent sections.
3.1 Site Alternatives – Aromatic Naphtha Tank Currently, two
site alternatives within the Sasol Industrial Complex are under
consideration for the installation of the hold up tank with a
capacity of approximately 11500 m3 for storing aromatic
naphtha:
3.1.1 Site 1 (Preferred) This site is located in the Eastern
tank farm and the tank is proposed to be located in Unit 256 within
a footprint of approximately 35 m by 65 m. This site is preferred
because of its proximity to the existing SCC aromatic naphtha tank,
process feed and maintenance tanks which allows synergy. The
proposed CTN and existing SCC aromatic naphtha tanks will be
interchangeable with each other doing tank turnarounds.
3.1.2 Site 2 (Alternative 1) This site is located in the Western
tank farm and the tank is proposed to be located in Unit 56 within
a footprint of approximately 35 m by 65 m. Site 2 is some distance
away from the process feed and maintenance tanks. This site has
been selected as an alternative because it can accommodate the
biggest size tank.
3.2 No-go Alternative Nationally, the reduction of benzene in
fuel is being undertaken under the Clean Fuels 2 Programme. The
anticipated deadline – 2017, is the year by which fuel produced in
South Africa must adhere to the fuel specifications (i.e. reduce
the benzene content in fuel from 3 volume% to 1 volume %),
standards and Euro V emissions (Department of Energy, 2011)4. If
this project does not go ahead, Sasol Synfuels will not be able to
comply timeously with the fuel specifications, standards and Euro V
emissions. As a result, South Africa will be restricted from
exporting fuel to other countries that purchase fuel compliant to
the Euro V emissions and this will in turn increase the country’s
dependency on imported crude.
4 Department of Energy, 2011. Discussion document on the review
of fuel specifications and standards for South Africa.
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4 GENERAL DESCRIPTION OF THE STUDY AREA
4.1 Geology Sasol’s Secunda plant is underlain by rocks
belonging to the Vryheid Formation of the Ecca Group, Karoo
Supergroup. These rocks primarily consist of sandstones, shales and
coal beds and are extensively intruded by dolerites of Jurassic
age. The dolerites occur both as sills and linear dyke structures
that may extend over tens of kilometers.
4.2 Topography and Soils The topography of the greater study
area is relatively flat and stable with little agricultural
potential. The greater study area falls within the Karoo
Supergroup, however the proposed site is highly transformed. The
highest point of the site elevation is 1600 m above sea level.
Soils in the proposed area have been disturbed with the historical
establishment of the Secunda Complex in the 1970’s where the
existing soil was replaced with a 1:1 mixture of dolerite and ash.
The importation and compaction of fill material has inherently
created a near impermeable soil horizon, minimizing the potential
for the ingress of contaminants from surface into the underlying
subsoil.
4.3 Water Resources
4.3.1 Geohydrology (Groundwater) The groundwater at the Sasol
Complex is characterised by two groundwater aquifers, including a
weathered aquifer occurring at a depth of between 8 and 14 m below
existing ground level, and a fractured rock aquifer occurring at
depths greater than 20 m below existing ground level. The weathered
aquifer occurs within the weathered shale, siltstone and mudstones
of the Karoo Formation, this aquifer consequently has a low
permeability of, on average, 0.005 m/day, whereas the fractured
rock aquifer has a very low permeability of, on average, 0.0004
m/day. The low permeability’s of the weathered and fractures rock
aquifer will limit the movement of contaminants within the
groundwater system. Groundwater flows in a northerly direction
towards the Klipspruit with a relatively low hydraulic gradient of
0.08, based on topographical elevations.
4.3.1.1 Groundwater Quality Monitoring boreholes located within
the factory and to the north of the Klipspruit have indicated the
character of the groundwater quality to be dominated by inorganic
components, calcium, sodium, nitrate, ammonia, sulphate, iron and
manganese. As could be expected, groundwater quality monitoring
boreholes in close proximity of contaminant sources reflect
localized elevated contaminant levels. Usually, this occurs at a
shallow depth of about 5 m. However, it should be noted that
background total dissolved concentrations in boreholes within the
greater Secunda area could reflect values up to about 850 mg/l. It
is noted that a 5 km exclusion zone has been established in terms
of groundwater abstractive use around the Complex. Consequently
there are no direct users of groundwater within the area of
potential influence.
4.3.2 Hydrology (Surface Water) The Sasol Secunda Industrial and
Mining Complex is located in the upper reaches of the Waterval
River, affecting the following tributaries of this river: Klein and
Groot Bossiespruit Brandspruit Klipspruit Trichardspruit
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The above streams combine into the Trichardspruit and after the
confluence with the Grootspruit, the Trichardspruit joins the
Waterval River. The water quality and flow profile of the Waterval
River changed substantially from the time Sasol Industrial and
Mining Complex was established in the late 1970’s. A notable
portion of the salinity generated in the Waterval River catchment
now originates from the Trichardspruit sub-catchment in which the
Sasol Secunda Industrial and Mining Complex is located.
4.3.2.1 Surface Water Quality Sasol Synfuels monitors the
quality of water in the adjacent surface water streams in
accordance with license conditions. A review of Sasol Synfuels
monitoring data for the Klipspruit (RESM 17) being the upper
catchment, RESM 7 being midpoint of the Northern Boundary section
of the Klipspruit of the Complex and RESM 6 being at the Charlie 2
Bridge exit of the Northern Boundary section of the Klipspruit,
indicates some variability in water quality, principally associated
with the seasonality of flow in the Klipspruit, and extended
periods of no flow or low flow. The surface water qualities are
principally characterised by the presence of inorganics. Elevated
salts concentrations have been observed to occur during periods of
relatively high flow, suggesting that salts accumulated in the
upper catchment are washed into the Klipspruit at such times. It is
noted that stormwater is not released directly to the Klipspruit
from the Complex but routed through the API containment dams and
quality checked for compliance before release, treatment or reuse.
RESM 11 and 13 are surface water quality monitoring points on the
Bossiespruit, forming the southern boundary of the Sasol Synfuels
Complex. RESM 1 is the water use license compliance monitoring
point after the convergence of the Bossiespruit and the Klipspruit
and prior to the watercourse leaving the Complex boundary.
4.4 Climate and Local Weather Conditions Local meteorological
data was obtained from Sasol which operates a network of monitoring
stations in the area. Meteorological data for the period January
2006 – December 2010 was obtained from the Club and Langverwacht
stations. Meteorological parameters recorded at these stations
include wind speed, wind direction, temperature, humidity and solar
radiation. Given the close proximity of these stations to the site
under investigation, data from these stations is considered to be
representative of the prevailing meteorological conditions in the
area.
4.4.1 Wind Wind roses comprise of 16 spokes which represent the
directions from which winds blew during the period. The colours
reflect the different categories of wind speeds. The dotted circles
provide information regarding the frequency of occurrence of wind
speed and direction categories. Based on an evaluation of the
meteorological data provided, winds for both stations generally
predominate from the north-easterly and north-westerly sectors
(Figure 5). However, winds at the Club station have a higher
frequency of occurrence from the north-westerly sector than
observed at the Langverwacht station. In general, moderate to fast
winds are recorded at both stations, although faster winds are
noted to occur at the Langverwacht station. Calm wind speeds, which
are designated as wind speeds less than 0.5 m/s, occur infrequently
at both stations.
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FIGURE 5: PERIOD WIND ROSE FOR THE SASOL CLUB (LEFT) AND
LANGVERWACHT (RIGHT) MONITORING STATIONS FOR THE PERIOD JAN 2006 –
DEC 2010
A diurnal trend in the wind field is recorded at both stations
(Figure 6). At the Club station, winds originate predominantly from
the north-east, east-north-east and east during the night–time
(12:00 – 06:00). A shift is observed during the day-time (06:00 –
18:00), with a higher frequency of winds originating from the
west-north-west over this period. At the Langverwacht station,
winds originate predominantly from the east-north-east and
north-east during the night-time (Figure 6). During the day-time,
winds occur with a higher frequency of occurrence from the westerly
and northerly sectors. As would be expected, faster winds are
recorded during the day-time period compared to the night-time at
both stations. Club Station
0:00 – 06:00
06:00 – 12:00
12:00 – 18:00
18:00 – 24:00
Langverwacht Station
00:00 – 06:00
06:00 – 12:00 12:00 – 18:00 18:00 – 24:00
FIGURE 6: DIURNAL WIND ROSES FOR THE SASOL CLUB AND LANGVERWACHT
MONITORING STATIONS FOR THE PERIOD JAN 2006 – DEC 2010
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The seasonal variability in the wind field at both stations is
shown in Figure 7. A similar wind field is recorded at the Club
station during all seasons, with winds originating predominantly
from the westerly and easterly sectors. Winds occur with a higher
frequency of occurrence from the easterly sector during the spring
(September, October and November) and summer months (December,
January and February). At the Langverwacht station, winds originate
predominantly from the west-south-west and south-west,
south-south-east during the spring and summer months. During autumn
and winter, a different wind field is observed with additional
components recorded from the north-east and east-north-east during
these seasons.
Summer
Autumn
Winter
Spring
Summer
Autumn
Winter
Spring
FIGURE 7: SEASONAL WIND ROSES FOR THE SASOL CLUB (TOP) AND
LANGVERWACHT (BOTTOM) MONITORING STATIONS FOR THE PERIOD JAN 2006 –
DEC 2010
4.4.2 Atmospheric Stability Atmospheric stability is commonly
categorised into six stability classes (Table 4). The atmospheric
boundary layer is usually unstable during the day due to turbulence
caused by the sun's heating effect on the Earth's surface. The
depth of this mixing layer depends mainly on the amount of solar
radiation, increasing in size gradually from sunrise to reach a
maximum at about 5 - 6 hours after sunrise. The degree of thermal
turbulence is increased on clear warm days with light winds. During
the night-time a stable layer, with limited vertical mixing,
exists. During windy and/or cloudy conditions, the atmosphere is
normally neutral.
TABLE 4: ATMOSPHERIC STABILITY CLASSES (PASQUILL GIFFORD) A Very
unstable Calm wind, clear skies, hot daytime
conditions B Moderately unstable Clear skies, daytime conditions
C Unstable Moderate wind, slightly overcast daytime
conditions D Neutral High winds or cloudy days and nights E
Stable Moderate wind, slightly overcast night-
time conditions F Very stable Low winds, clear skies, cold
night-time
conditions In general, the site experiences very stable (Class
F) atmospheric conditions (Figure 8). This is expected given the
predominance of a high-pressure anticyclone over South Africa which
produces stable, clear conditions.
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FIGURE 8: STABILITY CLASS FREQUENCY DISTRIBUTION FOR SASOL CLUB
(TOP) AND
LANGERWACHT (BOTTOM) MONITORING STATIONS
4.4.3 Temperature and Humidity Temperature affects the
formation, action, and interactions of pollutants in various ways5.
Chemical reaction rates tend to increase with temperature and the
warmer the air, the more water it can hold and hence the higher the
humidity. When relative humidity exceeds 70%, light scattering by
suspended particles begins to increase, as a function of increased
water uptake by the particles6. This results in decreased
visibility due to the resultant haze. Many pollutants may also
dissolve in water to form acids. Temperature also provides an
indication of the rate of development and dissipation of the mixing
layer.
5 Kupchella, C.E. and M.C. Hyland, 1993. Environmental Science.
Living Within the System of Nature. Prentice Hall, New
Jersey. 6 CEPA/FPAC Working Group, 1999. National Ambient Air
Quality Objectives for Particulate Matter. Part 1: Science
Assessment Document. Minister, Public Works and Government
Services, Ontario. Available at URL:
http://www.hc-sc.gc.ca/bch.
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Average monthly temperature and humidity at both stations for
the period Jan 2006 – Dec 2010 is given in Figure 9. Daily average
summer temperatures range between ~18°C and ~19 °C while winter
temperatures range between ~7 °C and ~11 °C. Relative humidity is
lowest during autumn and winter and highest in summer and
spring.
FIGURE 9: AVERAGE MONTHLY TEMPERATURE AND HUMIDITY FOR SASOL
CLUB (TOP) AND
LANGVERWACHT (BOTTOM) FOR THE PERIOD JAN 2006 – DEC 2010
4.4.4 Precipitation The area under investigation lies in the
summer rainfall region of South Africa, receiving a total annual
rainfall of 418 mm for the Club site during 2006 and 603.6 mm for
the Langverwacht site during the same period.
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4.5 Air Quality On 23 November 2007 the Highveld was declared a
priority area, referred to as the Highveld Priority Area, in terms
of section 18(1) of the National Environmental Management: Air
Quality Act, 2004 (Act No 39 of 2004). This implies that the
ambient air quality within the Highveld Priority Area exceeds or
may exceed ambient air quality standards, alternatively, that a
situation exists within the Highveld Priority Area, which is
causing or may cause a significant negative impact on air quality
in the area, and that the area requires specific air quality
management action to rectify the situation. The area declared as
such, includes inter alia the local municipalities of Govan Mbeki,
Dipaleseng, Lekwa, Msukaligwa, and Pixley ka Seme. Hence, five of
the seven local municipalities constituting the District form part
of the Highveld Priority Area.
4.5.1 Identified Sensitive Receptors A sensitive receptor for
the purposes of the current investigation is defined as a person or
place where involuntary exposure to pollutants released by the
project could take place. Receptors surrounding Sasol were
identified from satellite images and are given in Table 5. Local
communities in close proximity to Sasol include the towns of
Secunda, Evander and Trichardt with the informal area of Embalenhle
to the immediate west of the Sasol Complex.
TABLE 5: IDENTIFIED SENSITIVE RECEPTORS SURROUNDING THE SITE
Receptor Name Distance from Plant Direction from Plant
Secunda ~3 km NNE
Embalenhle ~5 km W
Evander ~7 km NNW Trichardt ~8 km NE
Kinross ~ 15 km NW
Standerton ~ 15 km SW Springbokdraai ~13 km W
Brendan Village ~15 km NW
4.5.2 Existing Sources of Air Pollution The Sasol Complex falls
within the Highveld Priority Area which was declared a priority
area by the Minister of Environmental Affairs and Tourism on 23
November 2007. The Highveld area in South Africa is characterised
by poor ambient air quality and elevated concentrations of criteria
pollutants due to the concentration of industrial and
non-industrial sources7. The priority area is comprised of parts of
Gauteng and Mpumalanga Provinces8. Secunda was identified to be an
air quality ‘hotspot’ in the Highveld Priority Area Air Quality
Management Plan due to frequent exceedances of the SO2 standards,
mainly due to emissions from the petrochemical industry and energy
sector in the region. Emission reduction measures, not specific to
each industrial sector, have been recommended in the Air Quality
Management Plan9. Such measures include the: Development and
maintenance of a site emission inventory, including greenhouse
gases; Development and implementation of a plant maintenance plan;
Development of a fugitive emission management plan; Implementation
of appropriate interventions to reduce fugitive emissions;
Installation and maintenance of appropriate abatement technologies;
Research into improving abatement technology and reducing
retrofitting costs.
7 Held G., Gore B.J., Surridge A.D., Tosen G.R., Turner C.R. and
Walmsley R.D. (eds), 1996. Air pollution and its impacts
on the South African Highveld, Environmental Scientific
Association, Cleveland, South Africa. 8 Zunckel., M, Naicker, Y.,
Raghunandan, A., Fischer, T., Crouse, H., Ebrahim, A and Carter,
W., 2011. The Highveld
Priority Area Air Quality Management Plan, Department of
Environmental Affairs, Pretoria. 9 See reference above.
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Sources of air pollution within the immediate area surrounding
the plant were identified from satellite imagery and a site
description of the area. Surrounding sources were identified to be:
Agriculture; Domestic Fuel Burning; Mining Activities; Veld Fires;
Power stations; and Other Sasol operations. A qualitative
discussion of each identified sources is provided in the
subsections below. The aim is to highlight the potential
contribution of surrounding sources to the overall ambient air
quality situation in the area. These sources have not been
quantified as part of this assessment, rather a qualitative
assessment of impacts is provided.
4.5.3 Agriculture Agricultural activity can be considered a
significant contributor to particulate emissions, although tilling,
harvesting and other activities associated with field preparation
are seasonally based. The main focus internationally with respect
to emissions generated due to agricultural activity is related to
animal husbandry, with special reference to malodours generated as
a result of the feeding and cleaning of animal. The types of
livestock assessed included pigs, sheep, goats and chickens.
Emissions assessed include ammonia and hydrogen sulphide10 (USEPA,
1996). Little information is available with respect to the
emissions generated due to the growing of crops. The activities
responsible for the release of particulates and gases to atmosphere
would however include: Particulate emissions generated due to wind
erosion from exposed areas; Particulate emissions generated due to
the mechanical action of equipment used for tilling and
harvesting
operations; Vehicle entrained dust on paved and unpaved road
surfaces; Gaseous and particulate emissions due to fertilizer
treatment; and Gaseous emissions due to the application of
herbicides and pesticides.
4.5.4 Domestic Fuel Burning Due to the close proximity of
residential developments, it is anticipated that low income
households in the area are likely to combust domestic fuels for
space heating and/ or cooking purposes. Exposure to indoor air
pollution (IAP) from the combustion of solid fuels is an important
cause of morbidity and mortality in developing countries. Biomass
and coal smoke contain a large number of pollutants and known
health hazards, including PM, CO, NO2, SO2 (mainly from coal),
formaldehyde, and polycyclic organic matter, including carcinogens
such as benzo[a]pyrene11. Exposure to indoor air pollution (IAP)
from the combustion of solid fuels has been implicated, with
varying degrees of evidence, as a causal agent of several diseases
in developing countries, including acute respiratory infections
(ARI) and otitis media (middle ear infection), chronic obstructive
pulmonary disease (COPD), lung cancer (from coal smoke), asthma,
cancer of the nasopharynx and larynx, tuberculosis, perinatal
conditions and low birth weight, and diseases of the eye such as
cataract and blindness12.
10 U.S Environmental Protection Agency, 1996. Compilation of Air
Pollution Emission Factors (AP-42), 6th Edition, Volume
1, as contained in the AirCHIEF (AIR Clearinghouse for
Inventories and Emission Factors) CD-ROM (compact disk read only
memory), US Environmental Protection Agency, Research Triangle
Park, North Carolina. Also available at URL:
http://www.epa.gov/ttn/chief/ap42/.
11 Ezzati, M. and D.M. Kammen, 2002. Environmental Health
Perspective. The health impacts of exposure to indoor air pollution
from solid fuels in developing countries: Knowledge, Gaps and data
needs. Risk Resource and Environmental Management Divisions,
Resources for the future, Washington DC, USA, Energy and Resources
Group and Goldman School of Public Policy, University of
California, Berkley California, USA.
12 See reference in Footnote 11 above.
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Monitoring of pollution and personal exposures in
biomass-burning households has shown concentrations are many times
higher than those in industrialized countries. The latest
International Ambient Air Quality Standards for instance, required
the daily average concentration of PM10 to be < 180 µg/m3
(annual average < 60 µg/m3). In contrast, a typical 24-hr
average concentration of PM10 in homes using bio fuels may range
from 200 to 5 000 µg/m3 or more throughout the year, depending on
the type of fuel, stove, and housing. Concentration levels, of
course, depend on where and when monitoring takes place, because
significant temporal and spatial variations may occur within a
house. Field measurements, for example, recorded peak
concentrations of > 50 000 µg/m3 in the immediate vicinity of
the fire, with concentrations falling significantly with increasing
distance from the fire. Overall, it has been estimated that
approximately 80% of total global exposure to airborne particulate
matter occurs indoors in developing nations. Levels of CO and other
pollutants also often exceed international guidelines13. Although a
high percentage of households in the area are electrified, the
burning of domestic fuels for heating and cooking purposes is
likely to occur in informal areas surrounding Sasol. Even in
electrified areas, households make use of domestic fuels due to
high electricity costs and the traditional use of such fuels. Based
on the Census 2001, coal and paraffin are predominantly also used
in the nearby informal area of Embalenhle, which is located
approximately 5 km to the west of Sasol.
4.5.5 Mining Activities Mining activities surrounding Sasol
include Winkelhaak Mines (Evander Goldfield). Mining activities and
the extraction of material results in the formation of discard or
slimes dams to accommodate the waste material. The surrounding
residential areas of Evander, Embalenhle, Secunda and Trichardt
will likely be exposed to elevated dust levels from the
neighbouring slimes dams. Dust originating from slimes dams has in
recent times become more than a nuisance factor. The health
implications of this dust are now being studied in more detail and
as the information becomes available local communities are becoming
more emotional and concerned in regards to their health.
4.5.6 Veld Fires A veld fire is a large-scale natural combustion
process that consumes various ages, sizes, and types of flora
growing outdoors in a geographical area. Consequently, veld fires
are potential sources of large amounts of air pollutants that
should be considered when attempting to relate emissions to air
quality. The size and intensity, even the occurrence, of a veld
fires depend directly on such variables as meteorological
conditions, the species of vegetation involved and their moisture
content, and the weight of consumable fuel per hectare (available
fuel loading). Once a fire begins, the dry combustible material is
consumed first. If the energy released is large and of sufficient
duration, the drying of green, live material occurs, with
subsequent burning of this material as well. Under suitable
environmental and fuel conditions, this process may initiate a
chain reaction that results in a widespread conflagration. It has
been hypothesized, but not proven, that the nature and amounts of
air pollutant emissions are directly related to the intensity and
direction (relative to the wind) of the veld fire, and are
indirectly related to the rate at which the fire spreads. The
factors that affect the rate of spread are (1) weather (wind
velocity, ambient temperature, relative humidity); (2) fuels (fuel
type, fuel bed array, moisture content, fuel size); and (3)
topography (slope and profile). However, logistical problems (such
as size of the burning area) and difficulties in safely situating
personnel and equipment close to the fire have prevented the
collection of any reliable emissions data on actual veld fires, so
that it is not possible to verify or disprove the hypothesis.
13 Ezzati, M. and D.M. Kammen, 2002. Environmental Health
Perspective. The health impacts of exposure to indoor air
pollution from solid fuels in developing countries: Knowledge,
Gaps and data needs. Risk Resource and Environmental Management
Divisions, Resources for the future, Washington DC, USA, Energy and
Resources Group and Goldman School of Public Policy, University of
California, Berkley California, USA.
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The major pollutants from veld burning are PM, CO and VOCs.
Nitrogen oxides are emitted at rates of from 1 to 4 g/kg burned,
depending on combustion temperatures14. Emissions of SOx are
negligible15. A study of biomass burning in the African savannah
estimated that the annual flux of particulate carbon into the
atmosphere is estimated to be of the order of 8 Tg C, which rivals
particulate carbon emissions from anthropogenic activities in
temperate regions16.
4.5.7 Power stations There are numerous Eskom coal powered
stations such as Duvha, Kriel and Tutuka that are located within
the Highveld Priority area. The burning of coal for power
generation results in significant emissions being generated. At the
power stations surrounding the pipeline route, various mitigation
measures have been put in place at the stations to reduce the
emissions before entering the atmosphere, these include bag filters
or electrostatic precipitator (ESPs) for the removal of particulate
matter and ash, scrubbers for sulphur dioxide and over air burners
for oxides of nitrogen.
4.5.8 Other Sasol Operations The Sasol chemical complex in
Secunda operates numerous chemical processes. The products
manufactured include olefins, surfactants, polymers, solvents,
ammonia, wax etc. Emissions released during refining as they relate
to combustion processes include sulphur dioxide, carbon monoxide,
carbon dioxide, oxides of nitrogen and particulate matter. Other
pollutants released include various levels of volatile organic
compounds or heavy metals.
4.5.9 Air Quality Situation Sasol operates meteorological and
ambient air quality monitoring stations in Secunda (Club,
Bossiespruit and Langverwacht). These stations measure
meteorological and pollutant parameters including ambient CO, SO2,
H2S, NO, NO2, O3, PM10 and BTEX concentrations. The Department of
Environmental Affairs (DEA) also operates an ambient air quality
monitoring station in eMbalenhle. For the purpose of the study,
benzene, NO2 and PM10 were assessed in the Air Quality Impact
Assessment (AQIA).
4.5.9.1 Benzene Concentrations Annual average benzene
concentrations are in compliance with the annual average standard
of 3.2 ppb over the monitoring period at the Club and Langverwacht
stations (Figure 10). Annual average concentrations for 2009 and
2010 at the DEA monitoring station are also in compliance. Annual
average concentrations range from 0.34 – 0.56 ppb at the Club
station and 0.60 – 0.95 ppb at the Langverwacht station. An annual
average concentration of 0.01 and 1.66 ppb was recorded at the DEA
station in 2009 and 2010, respectively. The annual average benzene
concentration at all monitoring stations are presented in Table 6.
14 U.S Environmental Protection Agency, 1996. Compilation of Air
Pollution Emission Factors (AP-42), 6th Edition, Volume
1, as contained in the AirCHIEF (AIR Clearinghouse for
Inventories and Emission Factors) CD-ROM (compact disk read only
memory), US Environmental Protection Agency, Research Triangle
Park, North Carolina. Also available at URL:
http://www.epa.gov/ttn/chief/ap42/.
15 See reference in Footnote 14 above. 16 Cachier, H., Liousse,
C., Buat-Menard, P. and Gaudichet, A. 1995. Particulate content of
savanna fire emissions. J.
Atmos. Chem., 22(1-2), 123-148.
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FIGURE 10: ANNUAL AVERAGE BENZENE CONCENTRATION (PPB) RECORDED
AT TWO SASOL
STATIONS
TABLE 6: ANNUAL AVERAGE BENZENE (PPB) CONCENTRATIONS FOR ALL
MONITORINGSTATIONS FOR THE PERIOD 2006 – 2010. EXCEEDANCES OF THE
ANNUAL STANDARDS ARE HIGHLIGHTED IN
BOLD
Pollutant Station Annual Average
2006 2007 2008 2009 2010
Benzene
Club 0.40 0.44 0.37 0.34 0.34
Langverwacht 0.60 0.70 0.77 0.69 0.74
Secunda x x - 0.01 1.66
Notes:
x indicates station was not operational
– indicates insufficient data is available to determine annual
average
4.5.9.2 PM10 Concentrations Daily average PM10 concentrations
generally fall below the current National daily standard of 120
µg/m3 at the Sasol stations, although five exceedances were
recorded at the Langverwacht station in 2010, resulting in
non-compliance (Figure 11). Maximum daily average concentrations
range from 87 – 127.8 µg/m3 at the Club station and 85.16 – 192.5
µg/m3 at the Langverwacht station (Table 7). Higher concentrations
are recorded at the DEA monitoring station, with exceedances of the
daily standard frequently recorded at this site. The higher
concentrations recorded at this site are interesting given the
close proximity to the Langverwacht station (approx. 3 km). The DEA
monitoring station is located in Embalenhle, the burning of biomass
and domestic fuel in this area could contribute to the PM10 levels.
Maximum daily average concentrations range from 321.29 - 537.04
µg/m3 at this station (Table 7). A similar pattern is recorded at
all stations over the monitoring period, with a distinct
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seasonal trend evident in the datasets. Ambient PM10
concentrations increase during the winter months due to the
prevailing meteorological conditions which promote the stagnation
of pollution. Annual average PM10 concentrations are in compliance
with the annual standard at the Sasol stations and non-compliance
at the DEA station.
FIGURE 11: DAILY AVERAGE PM10 CONCENTRATIONS (µg/m3) RECORDED AT
THE SASOL STATIONS.
THE RED LINE REPRESENTS THE DAILY AVERAGE PM10 STANDARD OF 120
µg/m3
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FIGURE 12: DAILY AVERAGE PM10 CONCENTRATIONS (µg/m3) RECORDED AT
THE DEA STATION. THE
RED LINE REPRESENTS THE DAILY AVERAGE PM10 STANDARD OF 120 µg/m3
A similar diurnal signature is observed in diurnal PM10
concentrations at all three stations, although a sharper morning
and evening peak is recorded by the DEA station (see Figure 12).
This diurnal signature is consistent with domestic fuel burning
with elevated concentrations recorded in the early morning (05:00 –
09:00) and evening (17:00 – 21:00) periods. Increased domestic fuel
burning together with stable meteorological conditions promotes the
increase in pollution during these periods.
FIGURE 13: DIURNAL PM10 CONCENTRATIONS (µg/m3) RECORDED AT THE
SASOL STATIONS
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4.5.9.3 NO2 Concentrations Maximum hourly average NO2
concentrations are generally in compliance with the hourly standard
of 106 ppb and allowable frequency of exceedance for all monitoring
stations (Table 7) However, hourly average concentrations were in
non-compliance at the Sasol stations in 2009 (Figure 14), although
this is not observed at the DEA station (Figure 15). Lower NO2
concentrations are recorded at the DEA station compared to the two
Sasol stations. A seasonal trend is also observed in ambient NO2
concentrations at all stations. Annual average NO2 concentrations
are in compliance with the annual standard at all stations (Table
9).
FIGURE 14: HOURLY AVERAGE NO2 CONCENTRATIONS (PPB) RECORDED AT
THE SASOL STATIONS
FOR THE PERIOD JAN – DEC 2009. THE RED LINE REPRESENTS THE
HOURLY AVERAGE NO2 STANDARD OF 106 PPB
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FIGURE 15: HOURLY AVERAGE NO2 CONCENTRATIONS (PPB) RECORDED AT
THE DEA STATION FOR THE PERIOD JAN – DEC 2009. THE RED LINE
REPRESENTS THE HOURLY AVERAGE NO2 STANDARD OF
106 PPB Diurnal NO2 concentrations are given in Figure 16. A
similar diurnal signature is recorded at all three stations, with
elevated concentrations in the early morning (04:00 – 08:00) and
evening (16:00 – 22:00) periods. However, a much sharper peak in
concentrations is recorded in the morning at Langverwacht while the
evening peak also extends much later at the Langverwacht station.
These periods coincide with increased traffic volumes as well as
possible emissions from domestic fuel burning.
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FIGURE 16: DIURNAL NO2 CONCENTRATIONS (PPB) RECORDED AT THE
SASOL STATIONS
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TABLE 7: MAXIMUM HOURLY, DAILY AND ANNUAL AVERAGE PM10 (µg/m3),
SO2 AND NO2 CONCENTRATIONS FOR ALL MONITORING
STATIONS FOR THE PERIOD 2006 – 2010. EXCEEDANCES OF THE
STANDARDS AND ALLOWABLE FREQUENCY OF EXCEEDANCE (WHERE APPLICABLE)
ARE HIGHLIGHTED IN BOLD
Pollutant Station Max Hour Average Max Daily Average
2006 2007 2008 2009 2010 2006 2007 2008 2009 2010
PM10
Club N/A N/A N/A N/A N/A 87.00 92.58 94.65 87.38 127.8
Langverwacht N/A N/A N/A N/A N/A 103.64 85.16 102.65 130.49
192.5
Secunda(1) N/A N/A N/A N/A N/A x x 321.29 362.31 537.04
SO2
Club 171.49 93.35 222.22 177.82 176.4 38.22 20.60 49.88 32.45
29.1
Langverwacht 234.43 272.47 241.64 324.34 185.3 43.64 54.34 41.62
39.48 31.1
Secunda x x 67.13 194.26 164.24 x x 18.11 38.11 44.61
NO2
Club 59.30 132.21 107.26 262.54 257.2 N/A N/A N/A N/A N/A
Langverwacht 186.08 84.57 124.01 370.80 72.7 N/A N/A N/A N/A
N/A
Secunda x x 83.83 120.60 287.55 N/A N/A N/A N/A N/A
Notes: (1) Maximum daily average for 2008 is given for the
period Aug – Dec 2008
x indicates station was not operational
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TABLE 8: ANNUAL AVERAGE PM10 (µg/m3), SO2 AND NO2 CONCENTRATIONS
FOR ALL MONITORING STATIONS FOR THE PERIOD 2006 – 2010. EXCEEDANCES
OF THE ANNUAL STANDARDS ARE
HIGHLIGHTED IN BOLD
Pollutant Station Annual Average
2006 2007 2008 2009 2010
PM10
Club 28.08 25.62 30.54 - 30.4
Langverwacht 36.77 28.24 29.93 30.30 44.9
Secunda x x - 72.82 88.52
SO2
Club 6.36 2.82 6.01 6.99 7.2
Langverwacht 8.53 9.40 7.61 6.15 6.7
Secunda x x - 8.54 10.99
NO2
Club 3.92 6.99 5.89 13.20 10.8
Langverwacht 7.80 6.21 8.77 18.81 9.8
Secunda x x - 15.37 20.14
Notes:
x indicates station was not operational
– indicates insufficient data is available to determine annual
average TABLE 9: EXCEEDANCES OF THE NATIONAL STANDARDS (WHERE
APPLICABLE) AT ALL MONITORING
STATIONS FOR THE PERIOD 2006 – 2010
Pollutant Station Hourly Exceedances Daily Exceedances
2006 2007 2008 2009 2010 2006 2007 2008 2009 2010
PM10
Club N/A N/A N/A N/A N/A 0 0 0 0 1
Langverwacht N/A N/A N/A N/A N/A 0 0 0 3 5
Secunda N/A N/A N/A N/A N/A x x 21 64 98
SO2
Club 3 0 5 6 4 0 0 1 0 0
Langverwacht 13 21 16 4 7 0 1 0 0 0
Secunda x x 0 2 6 x x 0 0 0
NO2
Club 0 3 1 73 10 N/A N/A N/A N/A N/A
Langverwacht 1 0 3 190 0 N/A N/A N/A N/A N/A
Secunda x x 0 2 9 N/A N/A N/A N/A N/A
Notes:
x indicates station was not operational
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4.6 Noise The Sasol Synfuels Complex is a source of existing
noise as a result of current industrial processes that are taking
place. The noise at the Complex is within 85 dBA.
4.7 Social The proposed project falls within the Govan Mbeki
Local Municipality (GMLM) which is located in the north west of the
Gert Sibande District Municipality (GSDM). The GMLM has the most
diversified economy within the GSDM, dominated by the petrochemical
industry (Sasol II and III complexes) and coal and gold mining.
Secunda and Embalenhle are the closest town/communities to the
study area. The study area extends potentially across much of the
Govan Mbeki Municipality, which consists of Secunda, Embalenhle,
Kinross, Evander, Trichardt, Charl Cilliers, Leslie/Leandra,
Lebohang, Eendracht, Bethal and eMzinoni. The Govan Mbeki Local
Municipality has the largest number (53.8% or 99201 people)17 and
highest level of employment within the District. This could be
attributed to the fact that the GMLM is one of two local
municipalities that hosts the majority of all the mining,
manufacturing and agricultural activity taking place within the
District.
4.8 Land-use The Sasol Synfuels Industrial Complex is surrounded
by a number of different land uses i.e. industrial, residential,
commercial and agricultural. The middle to high income residential
area of Secunda is located approximately 5 km north-east of the
Complex and includes a variety of commercial activities. In turn,
the low cost housing development of Embalenhle is located 10 km
north-west of the site. Due to the highly industrialised nature of
the area there is an extensive infrastructural development
including an extensive road and rail network. The project will not
have an impact on the land-use.
4.9 Health and Safety The nature of Sasol’s business brings with
it substantial inherent safety, health and environmental (SH&E)
risks. The group’s annual sustainable development reporting
includes a comprehensive list of these potential risks, the most
substantial of which are: the risk of fire or explosion at sites
that host inventories of flammable hydrocarbons above ground; risks
associated with extensive underground coal operations; and toxicity
risks associated with the wide range of hazardous chemicals that
are produced. Sasol’s Safety and Health Essential Requirements are
compulsory and applicable to all new projects such as the proposed
project retrofitting of the gas turbines. The properties of
aromatic naphtha are attached as Appendix C.
4.10 Heritage The Sasol Synfuels Complex is a highly developed
Industrial area that has been in operation for more than 30 years,
the landscape has been changed by the development. None of the
structures have aesthetic, historic, research or historical
significance. There are no sites of archaeological or cultural
significance known on the proposed study area. Sasol will ensure
that all requirements of Chapter II, Section 38 of the National
Heritage Resources Act, Act 25 of 1999, are complied with in the
EIA process and that the comments and/or recommendations of the
relevant heritage resources authority responsible for the area in
which the development is proposed, are considered.
17 Gert Sibande District Municipality, 2009. Spatial Development
Framework.
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5 ENVIRONMENTAL IMPACT ASSESSMENT METHODOLOGY AND APPROACH
5.1 Approach to Undertaking the Study An EIA for the proposed
SGP 1B (new) project has been undertaken in accordance with the
Environmental Impact Assessment (EIA) Regulations published in
Government Notice No. R. 543, R. 544 and R. 545 of 2010 in terms of
Section 24 (5) of the National Environmental Management Act (Act No
107 of 1998) (as amended). The environmental studies are following
a two-phased approach: Phase 1: Environmental Scoping Study (ESS) –
complete. Phase 2: Environmental Impact Assessment (EIA) – this
report, including an Environmental Management
Programme (EMPr) to address impacts identified during the ESS
and EIA.
5.2 Environmental Scoping Study An issues-based ESS was first
undertaken for the project. Existing information and input from the
Authorities as well as Interested and Affected Parties (I&APs)
were used to identify and evaluate potential environmental impacts
(both social and biophysical) associated with the proposed project.
No fatal flaws associated with the proposed project were identified
through the ESS, although potentially significant environmental
impacts were identified as requiring further in-depth study within
the EIA. The Scoping Phase of the environmental studies provided
I&APs with the opportunity to receive information regarding the
project, participate in the EIA process and raise issues of
concern. The draft Environmental Scoping Report (ESR) was made
available at public places for I&AP review and comment from 15
November 2011 to 13 January 2012. All the comments, concerns and
suggestions received during the public participation process for
the Scoping Phase and from the draft report review period were
included in the final Environmental Scoping Report, which was
submitted to the MDEDET for review and decision-making and
subsequently the acceptance was signed on 07 February 2012 and
received on 11 April 2012.
5.3 Authority Consultation
5.3.1 Consultation with Decision-Making Authority The relevant
authority (MDEDET) providing input into the proposed project has
been consulted from the onset of this study, and will continue to
be engaged throughout the project process. The consultation process
to date with MDEDET aimed to determine specific authority
requirements with regards to the project, and ensure inclusion of
these in the environmental studies. Authority consultation to date
also included the following activities: Submission of an
application for environmental authorisation in terms of Section 26
of the EIA Regulations
(2010) on 14 September 2011. Approval of the application
documentation by MDEDET was received on 04 October 2011. Site visit
with MDEDET official, Mr Bheki Mndawe on 01 November 2011.
Submission of the final Environmental Scoping Report and Plan of
Study for EIA on 30 January 2012. Acceptance of the final
Environmental Scoping Report and Plan of Study for EIA was received
on
11 April 2012 (Appendix D).
5.3.2 Environmental Impact Assessment As part of the overall
project planning process, this EIA aims to achieve the following:
to supplement, where necessary, the assessment of the social and
biophysical environments affected by the
proposed project during the Scoping study; to assess impacts on
the study area in terms of environmental criteria; to identify and
recommend appropriate mitigation measures for potentially
significant environmental impacts;
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to complete an Environmental Management Programme (EMPr) for the
inclusion of proposed mitigation measures; and
to undertake a fully inclusive public participation process to
ensure that I&AP issues and concerns are recorded and
addressed.
5.3.3 Methodology – Assessment of Impacts Impact assessment must
take account of the nature, scale and duration of effects on the
environment, whether such effects are positive (beneficial) or
negative (detrimental). Each issue/impact is also assessed
according to the project stages from planning, through construction
and operation to the decommissioning phase. Where necessary, the
proposal for mitigation or optimisation of an impact is noted. A
brief discussion of the impact and the rationale behind the
assessment of its significance is provided below.
5.3.4 Impact Assessment Methodology The potential environmental
impacts associated with the project will be evaluated according to
it nature, extent, duration, intensity, probability and
significance of the impacts, whereby: Nature: A brief written
statement of the environmental aspect being impacted upon by a
particular action or
activity. Extent: The area over which the impact will be
expressed. Typically, the severity and significance of an
impact have different scales and as such bracketing ranges are
often required. This is often useful during the detailed assessment
phase of a project in terms of further defining the determined
significance or intensity of an impact. For example, high at a
local scale, but low at a regional scale;
Duration: Indicates what the lifetime of the impact will be;
Intensity: Describes whether an impact is destructive or benign;
Probability: Describes the likelihood of an impact actually
occurring; and Cumulative: In relation to an activity, means the
impact of an activity that in itself may not be significant but
may become significant when added to the existing and potential
impacts eventuating from similar or diverse activities or
undertakings in the area.
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TABLE 10: CRITERIA FOR THE RATING OF IMPACTS
CRITERIA DESCRIPTION
EXTENT National (4)
The whole of South Africa Regional (3)
Provincial and parts of neighbouring provinces
Local (2) Within a radius of 2 km of the
construction site
Site (1) Within the construction site
DURATION
Permanent (4) Mitigation either by man or
natural process will not occur in such a way or in such a time
span that the impact can be
considered transient
Long-term (3) The impact will continue or last for the entire
operational life of the development, but will be mitigated by
direct human
action or by natural processes thereafter. The only class of
impact which will be non-transitory
Medium-term (2) The impact will last for the period of the
construction
phase, where after it will be entirely negated
Short-term (1) The impact will either
disappear with mitigation or will be mitigated through
natural
process in a span shorter than the construction phase
INTENSITY
Very High (4) Natural, cultural and social
functions and processes are altered to extent that they
permanently cease
High (3) Natural, cultural and social
functions and processes are altered to extent that they
temporarily cease
Moderate (2) Affected environment is
altered, but natural, cultural and social functions and
processes continue albeit in a modified way
Low (1) Impact affects the environment
in such a way that natural, cultural and social functions
and processes are not affected
PROBABILTY OF
OCCURANCE
Definite (4) Impact will certainly occur
Highly Probable (3) Most likely that the impact will
occur
Possible (2) The impact may occur
Improbable (1) Likelihood of the impact materialising is very
low
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Significance is determined through a synthesis of impact
characteristics. Significance is also an indication of the
importance of the impact in terms of both physical extent and time
scale, and therefore indicates the level of mitigation required.
The total number of points scored for each impact indicates the
level of significance of the impact.
TABLE 11: CRITERIA FOR THE RATING OF CLASSIFIED IMPACTS
Low impact (4 -6 points)
A low impact has no permanent impact of significance. Mitigation
measures are feasible and are readily instituted as part of a
standing design, construction or operating procedure.
Medium impact (7 -9 points)
Mitigation is possible with additional design and construction
inputs.
High impact (10 -12 points)
The design of the site may be affected. Mitigation and possible
remediation are needed during the construction and/or operational
phases. The effects of the impact may affect the broader
environment.
Very high impact (12 - 14 points)
Permanent and important impacts. The design of the site may be
affected. Intensive remediation is needed during construction
and/or operational phases. Any activity which results in a “very
high impact” is likely to be a fatal flaw.
Status Denotes the perceived effect of the impact on the
affected area. Positive (+) Beneficial impact. Negative (-)
Deleterious or adverse impact. Neutral (/) Impact is neither
beneficial nor adverse. It is important to note that the status of
an impact is assigned based on the status quo – i.e. should the
project not proceed. Therefore not all negative impacts are equally
significant. The suitability and feasibility of all proposed
mitigation measures will be included in the assessment of
significant impacts. This will be achieved through the comparison
of the significance of the impact before and after the proposed
mitigation measure is implemented. Mitigation measures identified
as necessary will be included in an EMPr.
5.4 EIA Report (EIR) This Environmental Impact Assessment Report
(EIR) contains the following: Details of the EAP who compiled the
report and their expertise to carry out an EIA; Detailed
description of the activity/ies; Description of the property on
which the activity is being undertaken; A description of the
environment that might be affected by the activity and the manner
in which the physical,
biological, social, economic and cultural aspects of the
environment may be affected by the activity; Details of the public
participation process conducted during the Scoping Phase and the
ongoing consultation
during the EIA phase; Description of the need and desirability
of the activity including advantages and disadvantages that the
activity may have on the environment and the community that may
be affected by the activity; An indication of the methodology used
in determining the significance of potential environmental impacts;
A summary of the findings and recommendations of any specialist
report or report on a specialised process; A description of all
environmental issues that were identified during the environmental
impact assessment
process, an assessment of the significance of each issue and an
indication of the extent to which the issue could be addressed by
the adoption of mitigation measures;
An assessment of each identified potentially significant impact,
including cumulative impacts, the nature of the impact, the extent
and duration of the impact, the probability of the impact
occurring, the degree to which the impact can be reversed, the
degree to which the impact may cause irreplaceable loss of
resources and the degree to which the impact can be mitigated;
A description of any assumptions, uncertainties and gaps in
knowledge; An opinion as to whether the activity should or should
not be authorised, and if the opinion is that it should be
authorised, any conditions that should be made in respect of
that authorisation;
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An environmental impact statement which contains a summary of
the key findings of the environmental impact assessment; and a
comparative assessment of the positive and negative implications of
the activity.
A draft e