8.2.3 Atmospheric Dispersion Potential

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1 (d) Areas characterised by lelatively good air quality, i.e. ambient concentrations between the percentage of the standard/guideline constituted by background concentrations (pollutant-specific) and 50% of the relevant standard and/or guideline. (e) Pristine environments, in which ambient concentrations are less than, or equal to the background concentrations of each pollutants as a percentage of the selected guidelines and/or standards. For the purpose of the scoping procedure the latter three categories were grouped together as representing an acceptable class of air quality. Projects which are to be constructed in environments classified within this average urban - pristine grouping will be allowed to PROCEED to the subsequent phase, the low concentrations of pollutants currently in the region rendering it unlikely that emissions from the proposed development will result in the exceedance of air quality guidelines. Proposed developments within environments classified as being at risk of non-compliance with relevant ambient air quality gm'mines and/or standards, will be given a cautionary note but will be allowed to proceed should no PROCEED WITH CAUTION notes have been indicated in previous phases. Areas currently in non-compliance with relevant ambient air quality guidelines will be classified as unacceptable for the location of additional sources. hi instances where developments are proposed for a non-compliance area, it may be recommended that the user select an alternative site. Alternatively, it may be recommended that the user consider the possibility of buying an existing industry s pollution rights. The purchasing of so called pollution rights, more commonly referred to as emissions trading, is widely practised in various European countries and within the United States. According to this option, a project proposer would need to persuade existing sources within the region to achieve sufficient additional emission reductions. The project proposers may even find it desirable to provide the capital for an existing source to reduce its emissions so as to achieve lower ambient air pollution concentrations Atmospheric Dispersion Potential The dispersion potential model base serves to reconcile the macro- and meso-ventilation potentials of the proposed site and to categorize the ventilation potential in one of the following classes (Section 6.5.5): (a) Good dispersion potential; (b) Fairly good dispersion potential; (c) Potential risk of poor dispersion, caution recommended; and (d) Poor dispersion potential. 8-5

2 The manner in which such macro and meso-ventilation potentials are reconciled for a particular source location is given in Table 6.2. Proposed developments which are to be located at sites included in the first or second categories are entitled to PROCEED to '"ie next level. For proposed sites included in the third category (i.e. potential risk of poor dispersion), proposed developments are instructed to PROCEED WITH CAUTION. All proposed projects within the final category are not allowed to proceed to the next level and the scoping procedure is terminated. Li such instances it should be recommended that the project proposer consider various alternatives to the project proposal, such as the selection of an alternative site, and possible alterations to stack heights. Should such project changes not prove successful or feasible, it will be recommended that the proposed development be subject to a comprehensive air pollution impact assessment Sensitivity of Receiving Environment In the proposed scoping procedure the sensitivity of the recei kg t -rviromr.ent was classified according to three classes, viz.: sensitive, potentially sensitive and nonsensitive (Section 7.6). The air pollution scoping procedure is terminated for developments which are to be located within environments classified as being sensitive. It is recommended that such proposed developments be subject to comprehensive air pollution impact assessments. Developments within environments categorised as being potentially sensitive are allowed to PROCEED WITH CAUTION (should no previous cautionary note have been returned), whereas for nv:;-sensitive environments, project proposals are allowed to PROCEED Final Decision Making Phase Following the completion of all phases, with a maximum of one PROCEED WITH CAUTION returned, the proposed development will be given the GO AHEAD. It is expected that atmospheric emissions from such developments will have no significant impact on the receiving environment. The implementation of the proposed air pollution scoping procedure outlined is beneficial even if the proposed project is not allowed to proceed without further assessments being undertaken. Information gained during the scoping procedure would serve to i d e n t i f y and assign priority to issues requiring further investigation, thus facilitating the tailoring of air pollution impact assessments and reducing the costs and durations of such assessments. 8-6

3 8.3 Conclusion The methodological framework outlined in this section is designed to allow for scenario analysis. Opportunities are provided for the review of initial proposals and for the integration of alternatives to such proposals in instances where the impact of the proposals are found to be unacceptable. Such scenario analysis is fundamental to the integration of environmental planning into the project development process, rather than environmental impact assessments being viewed as an activity to be undertaken once the project plans have been finalised. Due to the data constraints within which the proposed scoping procedure is to be implemented, it was necessary to include several subjective principles and procedures m the methodological framework. Such subjective stipulations include the decision to terminate the scoping procedure following the second proceed with caution note returned, and the manner in which atmospheric dispersion potentials and the sensitivity of receiving environments are classified. Each of these stipulations should be seen to be open to review and revision, particularly should improved information become available. 8-7

4 CHAPTER 9 - RECOMMENDATIONS AND CONCLUSIONS 9.1 Introduction A real need exists for the successful incorporation of environmental considerations into planning and development strategies. The DEAT adopted the Integrated Environmental Management approach in the early 1990s, and recently rendered scoping and impact assessments mandatory for various activities. The implementation of IBM continues, however, to be undermined by the unavailability of comprehensive data bases and scientific procedures. Recent international and local shifts towards environmental management, based on the integrated pollution control (1PC) principle, have served to highlight this obstacle to the efiective integration of environmental assessment into the planning process. Implicit in the IRC approach is a shift from an air pollution control approach based solely on source-based controls to an air quality management approach incorporating effectsbased controls. Air pollution investigations in South Africa are particularly affected by methodological and data constraints. The use of air pollution impact scoping or screening has been impeded by the absence of objective scoping criteria and a readily accessible dispersion climatology data base. A clear need exists for the development and implementation of a methodological framework able to facilitate the scoping studies which will undoubtedly form an essential component of IBM, IPC and the new EIA regulations. A conceptual methodological framework for air pollution impact scoping was developed in the current study. The utility and strengths, current limitations and possible future development of each component of this framework is discussed in the sections below. 9.2 Structure of Methodological Framework The conceptual framework, designed to facilitate an assessment of whether proposed developments will impact significantly on the receiving environment, comprises five analytical phases: establishment of the type and extent of the proposed development s emissions; «assessment of existing ambient air pollution concentrations at the proposed site; characterisation of the atmospheric dispersion potential of the site; e analysis of the sensitivity of the receiving environment; and e integration of conclusions reached in the initial four stages into a decision making process. 9-1

5 The application of the decision making framework ensures that informed, transparent and reproducible decisions are made with regard to the acceptability of the proposed development, or the need for further assessment. The data bases, model bases and user interfaces for each of the five stages are outlined in the preceding chapters. The data bases were structured to provide the information required for the decision making, process, offsetting the need for extensive data collection and collation during the scoping procedure. Information on existing ambient air pollution concentration levels, macro- and meso-ventilation potentials, and the effects of criteria pollutants on various environmental components were included in the data base. The computation of industrial emission rates necessitates a detailed industrial data base containing various emissio i factors and information on industrial processes. The iron and steel industry was therefore selected for inclusion in the data base to demonstrate the utility of the firamework. In the establishment of the data base, use was made of the best available data. In certain instances where data were unavailable or insufficient, particularly within the dispersion climatological field, an attempt was made to generate such data. Model bases included in the scoping procedure were structured to fulfil the following functions: development of an emissions inventory for the proposed iron and steel plant, evaluation of existing ambient air pollutant concentrations, and the atmospheric dispersion potential at the proposed site, assessment of environmental sensitivity, and finally, evaluation of the acceptability of the proposed plant and the need for further more detailed investigations. The model bases draw on information, calculations and procedures contained in the data base, and on information pro vided by the user. 9.3 Acceptability of Predicted Emissions from Proposed Development An industrial data base should include data required for the inventory of emissions, in addition to information on air pollution control techniques which may be implemented by the industry, An emission inventory represents the starting point for any assessment of a proposed development s impact on the environment. Information on abatement measures facilitates the review of design and control options which may be considered to reduce the potential emissions from a proposed process. Should the relevant information be readily available, the industrial data base may also include information needed to assets the cost and control efficiency of such control measures, in addition to calculating the percentage of additional control required to ensure compliance with emission limits. 9-2

6 An industrial data base thus provides the information necessary for scenario analysis within the project planning phase. Options which may be considered should emissions be predicted to exceed acceptable thresholds (emission limits) may include: alterations to the type or amount of raw materials to be used; «changes in the process operations; implementation of additional or alternative abatement techniques; or * a combination of all of the aformentioned changes. Scenario analysis is designed to integrate environmental planning into the project development process. Environmental impact assessments should not be perceived as an activity to be undertaken once the project plans have been finalised. Emission limits, promulgated by the Chief Air Pollution Control Officer (CAPCO), represent emission levels achievable through the application of best practicable means. It is not currently possible to include the DEAT s emission limits in the industrial data base since such limits are generally finalised, following discussions between CAPCO and the project proposers as to what constitutes best practicable means. In the methodological framework, project proposals are classified based on comparisons between estimated emissions and the limits imposed by CAPCO (as input by the user). This classification provides a straightforward way of assessing the acceptability of emissions from the proposed plant, and integrating the results into the final decision making framework. In instances of non-compliance proposed developments would need to be altered or additional air pollution abatement techniques adopted. Alternatively, the existing emission limits may be renegotiated with CAPCO. The utility of the iron and steel data and model base is not limited to applications within air pollution scoping studies, but may also be applied in air pollution impact assessments. Should it be recommended in the final decision making phase that further evaluation of the proposed industry s impact is needed, the emission inventory established would provide the necessary basis for a full-scale air pollution impact assessment. 9.4 Incremental Impacts on Ambient Air Quality Existing ambient pollution concentrations at the proposed site need to be considered in order to assess the potential incremental effects of the proposed industry s emissions on the air quality of the region. Ambient air quality may either be assessed based on the compilation of an emissions inventory for existing sources and the modelling of dispersion from such sources to establish air quality levels, or on the basis of monitored levels of pollutants. In the current study, use was made of monitored levels of sulphur dioxide and particulates, measured at a large number of sites throughout South Africa. It is 9-3

7 recommended that existing air pollutant concentrations at a proposed site be compared to ambient air quality guidelines and standards in order to asses the potential which exists for further emissions within the rce In the calculation of air quality indices, reference was made to the ambient air quality standards and goals of various countries and organisations, including the US, the EU and the WHO, in addition to local air quality guidelines. Although local guidelines represent the basis on which the acceptability of air quality is determined, the evaluation and inclusion of the air quality standards of other countries in the deta base is recommended since: e current guidelines may be revised in the near future; there is currently escalating public pressure for the implementation of stricter air quality standards; «multinational corporations and bankers are increasingly placing pressure on local concerns to adhere to international standards; and «the consideration of more stringent standards is in line with the precautionary principle outlined in the new environmental legislation recently promulgated in South Africa (BEAT, 1998a; 1998b). The development of a single air quality index based on various air quality standards for application in air pollution scoping studies is problematic. Ambient air quality currently needs to be assessed on the basis of DEAT guidelines due to the legal implications of such guidelines. The development of a single air quality index, based solely on local guidelines would not, however, adequately reflect the acceptability of air quality in terms of human health and the natural and built environment. Three different indices (AQ-I, AQ-II, AQ-DJ) were, therefore, proposed for use in the scoping procedure: AQI-I reflects the relationship between monitored levels of pollutants and DEAT guidelines. AQI-n incorporates a combination of primary local and international guidelines and standards (i.e. standards are aimed primarily at the protection of human health).» AQI-1II defines air quality in terms of the relationship of measured levels of pollutants to secondary, more stringent air quality guidelines and standards designed to protect human welfare and the natural and built environment. Ambient concentrations of TSP, SO2 and PM10 monitored over various averaging periods (daily, annual) were used in the calculation of each of the three air quality indices, and the indices classified as follows: 9-4

8 Air Quality Class Definition of Class Ambient Concentrations as % of Standard or Guideline 1 non-compliance >100 2 risk of non-compliance average (urban) air quality relatively good air quality BC pristine environment < BC BC represents the background concentration of each pollutant as a percentage of selected guideline or standard. The lowest air quality class estimated for all pollutants over all averaging periods, was taken to be indicative of the air quality of the station. This was done to provide a conservative estimate of the pollution levels present in the region. For the purpose of the scoping procedure, air quality classes 3, 4 and 5 were taken to represent acceptable air quality. Proposed projects located in environments classified within this average urban - pristine group are allowed to proceed to the subsequent phase. The low pollution concentrations at such sites render it unlikely that emissions from the proposed development will result in the exceedance of air quality guidelines. Proposed developments within environments classified as being at risk of non-compliance with relevant ambient air quality guidelines and/or standards (air quality class 2), are given a cautionary note but are allowed to proceed, should no previous note of caution have been issued. Areas currently in non-compliance with relevant ambient air quality guidelines (class 1 sites) are categorised by the decision making framework as representing unsuitable sites for additional sources. In instances where developments are proposed for noncompliance areas, it is recommended that an alternative site be selected, or alternatively, that the project proposer consider the possibility of emissions trading so that the overall pollution burden is not increased. The current ambient air quality data base needs to be periodically updated so as to take into account changes in ambient nollutant concentrations. In the current scoping procedure, a proposed development is rej< cted should ambient concentrations of any of the pollutants taken into account, viz. TSP, PM10 and S02, be demonstrated to be in non-compliance with relevant air quality guidelines. The levels of such pollutants are thus perceived as being indicative of the general air quality of the area. The data base could in future be extended to include the evaluation of air quality based on ambient concentrations of additional pollutants, should such data become available. 9.5 Characterisation of Atmospheric Dispersion Potentials An atmospheric dispersion climatology data base provides the cornerstone for effective air pollution scoping studies. No readily accessible dispersion climatology data base is available for the assessment of regional dispersion potentials within South Africa. In the current study a data and model base able to provide a realistic qualitative description of the 9-5

9 air pollution dispersion potential of sites within South Africa, based on a limited number of input parameters, was developed. The dispersion climatology data base generated incorporates macro-scale ventilation potentials for all regions within South Africa, in addition to ventilation potentials for various meso-scale circulation scenarios Macro-scale Ventilation Potentials The macro-ventilation characteristics of a region are a function of the meteorological properties, spatial and temporal trends, frequency of occurrence, persistence, sequence of occurrence of prevailing synoptic systems and weather disturbances. The frequency and sequence of occurrence, and persistence of synoptic systems have, to date, only been investigated on a national scale. Such information is inadequate to facilitate the estimation of the regional dispersion potentials required for the dispersion climatology data base. A temporal air mass-based synoptic climatology was established in an attempt to provide the necessary information required for the calculation of regional ventilation potentials. The air mass-based synoptic climatology was generated, based on three years of upper air data for each of the nine rawisonde stations in South Africa, and the resulting synoptic classifications generalised for each region. Results from the three year air mass-based synoptic climatology were used to provide a single index of the macro-scale ventilation potential of each region for winter and summer. Synoptic systems identified were classified as either stagnating, ventilating or neutral systems, based on the consideration of the vertically averaged wind speeds, mixing depths and precipitation potentials characterising such systems at each station. The macro-scale ventilation potential was defined as the ratio of the percentage stagnating days within an episode to the percentage of days on which ventilating systems predominated. An episode was defined as a period in which stagnating systems persisted for four or more days. Based on the estimated macro-ventilation potential, regions were classified according to three classes; (i) pione- to poor dispersion, (ii) median dispersion potential; and (iii) good dispersion potential. Although it was intended that the synoptic climatology be undertaken for all seasons, it was only possible to include winter and summertime synoptics. Despite the initial inclusion of autumn and spring months in the assessment, the analysis of these seasons was terminated since the use of upper air meteorological data recorded at twelve hourly intervals proved inadequate to reflect the rapid transition between circulation patterns characteristic of these periods with the analytical technique selected accurately. It is recommended that further techniques be evaluated to facilitate such analyses, so that the synop tic climatology established may be expanded to include all seasons. In the establishment of a synoptic climatology for autumn and spring (based on the available twelve hourly interval upper air data), the use of alternative input parameters may improve the results generated. Relative 9-6

10 humidity could, for instance, be replaced by vapour pressure, and mixing heights could be computed for each twelve hour period and included as an input parameter. For the purpose of the current study it was necessary to limit the period for which the air mass-based synoptic climatology was established to three years. The development of such synoptic climatologies abroad have frequently been based on up to 30 years of data. The nature and usefulness of the results produced indicates that it would be worthwhile to extend the climatology to include an additional number of years. The consideration of a longer period would facilitate an analysis of the inter-annual variations in dispersion potentials. The proposed extension of the synoptic climatology would, however, require careful review of the availability and accuracy of the upper air data required, and the availability of considerable computational capacity to facilitate the manipulation of the large meteorological data sets. The air mass-based synoptic climatology, and the extension of this data base may provide valuable information for various areas of study. Temporal synoptic climatologies may be linked to large scale transportation patterns. In the US and UK, inter annual variations in the frequency of occurrence and meteorological characteristics of the synoptic types identified as part of synoptic climatologies are examined to facilitate climate change studies. Local studies are currently underway to assess the potential of fog as a source of potable water for rural communities in the eastern Drakensburg. The quantity of water which could be collected on a fog fence (per unit area) for each synoptic system, including ridging anticyclones, cold fronts and cut-off lows has been assessed. The development of a longterm synoptic climatology and the examination of inter-annual variations in the frequency of occurrence and meteorological characteristics of synoptic types could provide valuable information as to the ranges in the total water yield from this source Meso-scale Ventilation Potentials Ventilation characteristics for various generic meso-scale circulation systems were included in the data base to demonstrate the manner in which such circulations may be incorporated into the assessment of the dispersion potential at a specific site. Due to the complexity of establishing such generic models, meso-scale systems related to uneven terrain were selected for inclusion in the data base. Such systems included the impact of hills and valleys on the low-level wind field and atmospheric stability regime. Basjd on the nature of the proposed source (e.g. height of emission, location within the valley, proximity to hill), and the characteristics of the relief of the site (e.g. valley depth, hill slope and height), three meso-ventilation potential classes were defined: (i) poor dispersion potential (high probability of fumigation conditions), (ii) potential risk of poor 9-7

11 dispersion (macro-ventilation potentials need to be considered), and (iii) no risk foreseen due to meso-scale circulations (macro-ventilation potentials need to be taken into account) Reconciliation of Macro- and Meso-ventilation Potentials It is unlikely that all potential sources will be excluded for an entire region which is prone to poor dispersion. It was therefore decided that macro-ventilation potentials should only serve to provide a cautionary note rather than a decisive recommendation as to whether or not a planned development be allowed to continue. Meso-ventilation potentials were thus given a greater wei girting than were macro-ventilation potentials in the final classification of the overall dispersion potential of the site into one of four classes, viz.: (i) poor dispersion potential, (ii) potential risk of poor dispersion, caution recommended, (iii) fairly good dispersion potential, and (iv) good dispersion potential. It is proposed that the air pollution scoping procedure be terminated for proposed sites which are classified as being characterised by poor dispersion potentials. In such instances it should be recommended that the project proposed consider an alternative site, or that the proposed development be subject to a comprehensive air pollution impact assessment. 9.6 Sensitivity of Receiving Environments Air pollution impact assessment studies need to include an appraisal of the associated environmental risk. Such risk assessments comprise identification of potentially sensitive environmental components in the vicinity of the site, and characterisation of the risk to such receptors posed by the estimated emissions. During the air pollution scoping phase it is not possible to undertake a dose-response analysis and exposure assessment needed to quantify risks. The identification of potential risks was, however, included in the scoping procedure. The integration of risk identification not only provides for a more comprehensive assessment of the impact of a proposed industry during the scoping phase, but also provides the basis for risk assessment studies should a more detailed air pollution impact assessment be required for such an industry. In the proposed scoping procedure the sensitivity of the receiving environment was classified according to the following criteria: (i) whether or not the receiving environment is included in the list of environments identified by the DEAT as necessitating a full-scale impact assessment, (ii) proximity of sensitive receptors to the proposed site, (iii) dispersion potential of the site, and (iv) extent of emissions anticipated. Receiving environments are classified into one of three classes, viz.: sensitive, potentially sensitive and nonsensitive. The air pollution scoping procedure is terminated for developments which are to be located within environments classified as being sensitive,. It is recommended that such proposed developments be subject to comprehensive air pollution impact assessments. 9-8

12 9.7 Strengths and Limitations of Proposed Decision Making Framework The conceptual methodological framework comprises a holistic approach to air quality management, incorporating both source-based and efiects-based controls. The acceptability of a proposed industry's emissions is determined on the basis of source-based controls; emission inventory results being compared with emission limits promulgated by CAPCO. The inclusion of an assessment of existing ambient air quality, based on local and international air quality standards, reflects the integration of an effects-based approach. The analysis of atmospheric dispersion potentials and sensitivity of receiving environments also forms an integral component of the efiects-based approach. The integration of assessments regarding types and extents of emissions, existing pollution concentrations, site-specific dispersion potentials, and environmental sensitivities into the decision-making process posed a significant challenge. In order to ensure the integration of all aspects in a transparent and consistent manner, it was necessary to establish a well documented scoping procedure. Such a procedure is not only important to ensure the transparency during the scoping phase, but may also provide the precedent for subsequent ah' pollution impact assessments. The methodological framework incorporates several subjective principles and procedures. The more important of these include: the stipulation that the scoping procedure be terminated following the second cautionary note, classification of macro- and mesoventilation potentials into classes and the manner in which such ventilation potentials are reconciled for a particular site, and the criteria used in used in the classification of receiving environments. Each of these stipulations may be subject to review and revision. The potential revision of various components within the methodological framework, particularly in instances where additional information becomes available, would serve to enhance the validity of the framework. Such revisions need to be well documented so as to ensure the continued transparency and reproducibility of the decision making process. A fine line exists between attempting to store too much data in the data base required for air pollution scoping, and maintaining sufficient data to facilitate informed decision making. In the development of the current data base an attempt was made to incorporate only data essential to the decision making process. Should the data base be extended, all industrial, climatological, socio-economic data (etc.) incorporated should be shown to contribute significantly to the decision making process. The implementation of the proposed air pollution scoping procedure outlined is beneficial even if the proposed project is not allowed to proceed without further assessments being undertaken. Information gained during the scoping procedure would serve to identify and assign priority to issues requiring further investigation, thus facilitating the tailoring of air pollution impact assessments and reducing the costs and durations of such assessments. 9-9

13 The conceptual decision-making framework for air pollution scoping studies proposed in the current study may play a much needed role in preparing common ground between -t proposers, environmental authorities, and interested and affected parties. The t asparent and consistent nature of decisions made within such a framework could enhance communication, promote the review of project options early on in the planning phase, and assist in the resolution of disputes with regarding the proposed process. Where no compromises are possible, or where the impact of the proposed development requires further study, the methodological framework not only provides useful baseline information, but also establishes the precedent for transparency and consistency in subsequent air pollution impact assessments. 9-10

14 APPENDIX A INDUSTRIAL DATA BASE, MODEL BASE AND USER INTERFACE The detailed industrial data base, model base and user interface compiled for the integrated iron and steel industry so as to demonstrate die utility of the conceptual framework is presented in Appendix A. This appendix is contained in electronic format on the accompanying computer disk. A-l

15 APPENDIX B Table B.l. Final air quality classes(a) assigned each of the sampling sites. Sampling Site(b) Air Quality Index Sampling Site(b) Air Quality Index I n III I n m GAUTENG Johannesburg Albertan City Hall (C) New Redruth (C) Fordsburg (T) Alrode (I) Kempton Park Newmarket (I/R) CBD (C) Benoni Fisonsnywerheid (T) CBD (C) Sandton Industrial area (I) Marlboro (T) Westdene (R) Sandown (PR) Daveyton (R) Rivonia (R) Boksburg Meyerton CBD (C) CBD (C) Cinderella (I Bothdene (C/R) E aksburg North (UR) Kookrus (C/R) Lilianton (R) Pretoria Boksburg East (R) CBD (C) Reiger Park (R) Visage Str (I) Edenvale Myburg Str (UR) Bliondale (R) Arcadia (R) CBD (C) Scientia (R/T) Sebenze (I) Randburg Terrace Road (I/R) Blairgowrie (R) Germiston Malans Hof (I/A161R) CBD (C) Randparkrif (R) Wadeville (I) Roodepoort De'vilJe (UR) CBD (C) Primrose (R) Florida (R) Tembisa (R) Weltevredenpark (R) Kathlehong (R) Wilropark (R) Bedfordview (R) Veereniging Brakpan Powerville (I) CBD (C) CBD (C) Gelulcsdal (R) Drieriviere (R) Leachville (R) Bedworthpark (R) 3 2 2

16 Table B.l. Final air quality indices for each of the sampling sites (continued). Sampling Site(b) Air Quality Sampling Site(b) Air Quality Index Index I n HI I H HI GAUTENG MPUMALANGA Springs Middleburg CBD (C) CBD (C) New Era (1) Weber Str (I) Nuffield (I) Fontein Str (R) Bus Terminus (C) Nelspruit Selection Park (R) CBD (C) Petersfield (R) Industrial Area (I) Vanderbijlpark Lowveld High School (R) CBD (C) Witbank Municipal workshop (T) CBD (C) ' Municipal test ground (PR) Ferrobank (I) Municipal licence office (PR) Extention 10 (R) Municipal pool (R) TasbetPark(R) Lekoa (Sebokeng) (RUR) NORTHERN PROVINCE FREE STATE Pietersburg Bethlehem CBD (C) CBD (C) Armadale (PR) Workshop (I) NORTH WEST PROVINCE Jordaine (R) Klerksdorp Bohlokong (R) CBD (C) Bloemfontein Joubeiton (R) CBD (C) Potchefstroom Lang Str (T) CBD (C) Bayswater (R) Gouws Str (R) Mkuhlone Str (R) Tlokwe (R) Kroonstad Dassie Rand (R) Municipal workshop (C/PR) KWAZULU NATAL Voortrekker Hospital (PR) Durban Seisoville (R) City Hall (C) Welkom Municipal Centre (C) CBD (C) Congella Fire Station (T) Municipal workshop (I) Southern Sewerage works (I) Thabong (R) South Bluff Reservoir (PR) Sasolburg Wentworth Reservoir (PR) CBD (C) Brighton Beach Reservoir (R) Magasyn (T) Durban North (R) Grootfontein (R) University (R) Vaalpark (I) Merebank (RyT) B-2

17 Table B.l. Final air quality indices for each of the sampling sites (continued). Sampling Site(b) Air Quality Index Sampling Site(b) Air Quality Index I n m I n m KWAZULU NATAL EASTERN CAPE Durban East London Riverside (R/T) CBD (C) Isipicgo (R/T) Cambridge Clinic (R) Chatsworth (R) Port Elizabeth Bluff Army Base (R/T) CBD (C) Amanzimtoti Deal Party Estate (T) CBD (C) Markman Township (T) Industrial Area (1) Perseverance (I) Fire Station (R) Neave Township (I/R) Estcourt North End (TZR) Alfred Str (C) Sidewell (TZR) Connor Str (C) Mount Croix (R) Newcastle Kwazakele (R) Allen Str (C) WESTERN CAPE Edison Str (I) Cape Town Flame Cres. (1) Foreshore (C) Drakensberg Commando (R) Drill Hail (C) Pinetown Epping Market (T) CBD (C) Paarden Eiland (J) Cowie's Hill (R) Other Gillits Rd (I) Bellville South (R) Pietermaritzburg Edgemead (R/I) CBD (C) Pinelands Nerine Cres. (R) Mason's Mill (I) Parow (R) Joliffe (1/R) Goodwood (R) Old Beer Hall (Ml) Elsies River (R) Northdale (R/I) Khayalitsha (R) Chase Valley (R) Richards Bay Alton (I) Polaris (I) Arboretum Ext 1 (R) Meerensee (R) Water works Arboretum (R) Air Qual Lab (R) (a) T he definition o f the air quality classes are defined as follows: (1) non-compliance w ith guidelinesor standards; (2) risk o f non-com plknce; (3) average/urban air quality; (4) relatively good air quality; and (5) pristine environment. (b) The nature o f sampling sites are given by the following letters: C - Central urban areas; I - Industrial areas; R - Residential areas; and R U R - Rural areas. B-3

18 Table B.2 Specific air quality classes(a) for each pollutant over each averaging peric Letters A to G, which represent the pollutant and averaging period taken into account, are defined following the table. Classes generated for all three air quality indices (AQI) are given. Iit0 I B ; 0 1& «s Hra k 3 I u * o to U P3 o to U fo m cn xf*'sh rt ^ m Tf Tf Xj* Xh Ti' ^ ^ X?- Xf*Xf" Tf Tj" 'd cn sf Tf Tf rj- m xh fn xh ^ xj- 'd- =*rf rn xj- m rj- xj- cn m ^ xt- Tf Tf e n c N ^ t Tf Tf Tf T-< ^ c n s t s t c s m xt- rj- m m cn xt- -=d- xr Tf- Tt xi- xt- un rj* xh in vn in xt vi Tf m in m cn cn m cn cn x}*xj- ^ xt* xt1 xf- xf- rj- xf" Tt xf xt" Tf Tf Tf Tf inxhxh xh m xf xh xj- xl* m x}- xf- xh x t cn sj- xj* xj- xt- xf- xr xh xi* xfxt- m xf- xl* xt- xf- m c o x l 'x f x h c S c ^ Xt* xh ^ Xl- Xf- xh Xi- X?* x*- CN xl* xf* xh x t (N xf xj- xh xl* cn xl* xh xf xt x}* x)- xr xf xfin xj- m xt- xt- xt- xf- in xh x}- in in in xf- in xt* in <n m (4 M ^ ^ xf 'tr "rf xf ^ xt xf xf 'v' Ii i.b O (n cnm xf xj* xh xf* xf- in xf-x } - g a OT1 "< 6 M m m m m ft) rr> R 0 1 s$ pi e rrl d 1 l 1 x}* xh xj- xh xh xj- xt* xt* xf* xj- xh xj* xj- xt- xl* x t x h r t x j-x j-x t- x h x h x h x h xh xt- xj- xt* xf* xj* x j- x t- x h * * xj* xf- xh x}- xj" xf xf" in xj* in xt- ^ x t in xf- xf in vi in xr <n ' f in in i. e cd 6. S- g 0 iii iii (2 ^ 1 P O A B-4

19 «S a 'B Ist<i ts» M m Tf m rr m m y N N -f m n -e ^ '»»>* I? 1 O'k e f=i "st "<3""3" Tf Tf Tf Tf Tf ^ p % H ft U sf* cn xr rf rj* rj* in vi m ^ Tfco Tf Tf ^ xh ^ m co <n x$*m "^f- d*xf* "sh^ -sj* cn -^t* rn m id- rj* cs ^l*cn xh ^ xj- m m xh en t}* ^ xi* xt* r^co cn xh co co Tf- CO r-1 xh Xj* CO ' T t j - o ) CS uo CO CS ^ ' n* rj* -?} el* Tf" Tf" Tf 'sh ^ tn in xh in xj- xj* xi- xt* x}* «n in «9 s i % ii s a i! % o p=( U < «s I I % 6)Has u & Is & o T*" M ^ co COT?* cs co -Tf^Tf eo COTf (O M"ti* ^ rf xl* ^ rh tj* "d' xj* xj* r}* 'd* 'd- 'd- "3" %TTf- "3" r t co xt 'd' co xt- 'd- xl- 'd* xh xf co d* in in»n 'd- 'd* '4* 'T "^h "d- co "'d* 'd* sj* xh co xh xj* xj- coco»n xt cn xt st* "cf xh xhrj* T t CN ^ c o CO ^ rj* CS T f CO xf- xf- CO CO n * rj* CO St* -st* r t 'd* r l- rjxh cn xh xh "d* d* «d' co ro in co cn ish ^ ed* 'd- 'dxj* -d- in Tf T^- in Tf Tj- 'd- xf rj- rj- rf ^ in m T}*T? M* CO d ^ It ^ Sf Th XTTf Tf ^ 't "d- 'd* 'dxt* xf xj- co xj- xj- xt* xt- 'd* 'd- d- "d* 'd- xf* 'd- Tf- -a- in Tf Tj- Tf in rftj-xf id' xj- xj- xt* xt* ^ in in rd* Xh r*- r j - id - ^ d* 'd- 'd* xfin in in 'd- 'd- 'd* 'd" 'd- Tf- xt* xf xt* xf- xt* 'd" -sh -sj- in xf1xh -^d- <d* d* 'd- ^d- 'd' B-5 % S I g& Ill1 1 1l! u lik3 6 t 61nil ' u i s II6 g'l i28 ^11! ( 3 a 2(58 5 ( f: is i s a a, I I

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21 II e vi -rf c n x j- c n x t x i ' x f x r c n * * x r c n xj* CN xj- xf* x f x}* I «s o s 5 ^ «u Tf m Th 'd* cn rj- rj* ^ <N T f T f CO "3" Tf Tf Tf Tf Tf CN x h CN ^ x f x h xj* x f x t- c n x t- x h x t xfx+* xt* c n xt* xi* xi- xjx ^ x f r x } * x t xj- xt* x j- c n xt* x f x}* xt* xj- x f x h xj- c n d* x h 1% P3 rf cn st cn CN x f x? c n c n x h x t x l- x f x}* x f x r x f xt* c n x i- x f III o ^ CN xh T f x f Xj- x f x f x f v n V ) x f xj- x}* v n i n xj* x h i n x j i n x h x f ( N ^ x f <n x f x f (N x f x f x f c n x f X f c n x f X f x f x f c n X f X f X f x f x f x f m x f x f x f X f fc l x f x f X f x f x f x f c n X f x f x f x f x f m X f x f x f x f c n ^ x f x f x f i! 55 S p. u x f c n x f CN x f c n x f x f x f x f x f x f x f x f cn x f x f CN x f x f x f x f x f x f x f x f x f x f x f c n x f x f x f x f x f x f x f x f x f c n x f x f m I& «X f CN x f c n x f x f c n x f x f x f c n x f x f x f x r x f x f x f m x f x f c n x f x f x f x f x f x f x f i n x f x f x f i n i n x f x f m x f m x f ^ a n y x f T f x f x f x f r f x f x f x f X f X f c n x f ^ x f ^ X f X f o vi ^ -gf x f x f x f x f 1 3 aa 9 # 1 4 & Ec M X f x f X f x f c n x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f x f i n x f x f x f x f x f c n x f x f x f x f x f x f x f x f X f x f x f x f x f x f x f x f x f x f x f x f i n i n xj* x f i n x f m x f a I H3f. 1 II Hi! I e I. Ig t cdxj 3 P. as «! CQ*3 m 8 S 2 8 S 3 5 $ S

22 II 8 S* N M N ^ m m m 1-4 M ^ ^ N m m e 'd- cn «i xt r~<o~i ^ 'd- cs xi* xi* xt* s o I K g - "d 8s! S' «8 i l l I k N u xf 0 i n T f xi* rj - xf* cn cn ^ c^ xf- xh m x h r t xh xf Tf Tf "3" "f Tj* Xf "^r xt-,y-,st m xf xf xh ^ Tf cs <N cn xf Tf" Xl* Tf" TT Tf N Vn Xf x f x f -H Xf- T i m x f xt- m Xj* Xj* X}* x r x f x t x h xl* x f xj* x h t j - c n xt* x h tj- c n c n xf- x f xt- xj* rj* ^ m m c n xt* x f x t c n ^ x}- xj- xf- x h x h r*v C 4 c n xt* in in cn cn cn*n xj* r f x}* x f x f x f T f x f * n x}- xi* xt* x}- Xt Tf x? <s <s e«^ tn eo vh ra h <s xs* xf m m co xf x h x h x h (N x h cn x h x h x h m x h x h x h m x h "^h xh xh m m f - 1 <N xh x h c n xh xh xh i ii P w u xh Xj- Xj- Xl* x j- x f x h xj- o n x}* x f x h CN <N CM x h x h x h x h x j- 7-4 m x h x h c n x h xt- x h Th xh xh xh xh xh x h xh xi* xh cn xh xh xh m r o xh xh xh x h xh xh vo m r o xh B-8!«& M xh xh xh xh f n in xh xh m xh xj- xh xh xh x<- xh c n cn i n m x h m m i n xh xh ""d* xh xh xh xh xl1 i n xh xh xh n S' o Tj* ^ x h x h fo «/> w r-*<<n ^ xh w "sh xf* rh x h x h x h x h xh x h CN x h CS x h x h xh m xh x h xh if=< 1 if«i n x h x h x h x h 3- m in x h x h i n t n x h x h x h i n x h x h m u n x h xh xh m cn t- < c<l xh xh cn xh xh xh xh ^h xh co c o ( S co xh xh c o ^ xh xh xh xh xh xh xh xh xh xh xh x h xh xh xh xh r t xh ^ xh xh xh i n x h xh xh xh e I If B U M Bfl a I ill s lli! % u di f e w ill im il! ll y 1 g

23 s 8 a T3 I I, a 0 ^ m m m roco Tf rj- r^- *sf Tf" Tj- Tf ^ Tf rf1 Tf- Tf Tj" Tf" Tj" Tf Tf Tf Tj" ^ T*" ^ *Sf rj* Xj* xf* x h «r> ^ '^j- 0*1 Tf Tj* Tj- -Tj- Tj- Tf- Tf rf cn Tf Tf Tj- Tj- ^ "n* en ^ cn m * cn cn "^t s? ^ cn ^ n Tf in TT Tj- Tj- Tj" Tj- Tj- in TT Tj- M Tf" T)- TT ^ Tj- Tf- T)" Tj- Tf cn Tf cn Tf 'Tj* cn ^ rd- xt- ^ '4* Tf Tf Ti Tf- cn ^ 'T r t Tf Tj- in cn T)- Tf vf -^r in»n vn if ^ cn if cn if cn cn if if if if it- if «Vi m cn cn cn cn in in in in if if cn rf cn in cn cn if if if m in m n m m m Tj-rj- inmmm if if if if if in if - f if m in in in in 1 a g vi 8 8 #3 «% 0 if if Tf If if if if if If If if if If If If If If If if If If if If If if If if if if if in if if cn if Tf if if if if f f i f f if cn f f f f <n cn cn cn cn cn in in in in in m wn in f f m m m in r f r f M r f rf ) r f f f ) ff ) r f r f r f f f ) r f (f) f in if f if f if f in if f *f f* cn f f f - f f f - f f f i f if cn i f cn if if cn if if if if if if if if if if cn f if if if if in cn if if if if in in in f if cn f cn f cn cn f f f f *f f if f f f cn in cn cn if f f m in in f if f f f m if f f* in in in in in B-9 f,f,f "f f -f f f f f f cn f f f f f f f f cn f cn e l ii i itw % e $ f i f f *f f f f f f f f f f f f f - f f f f f f f f f f f f f f in f f f f f in m m m in in in m f f in in in m e _ s m «IIB M B 15 M S A III M.3 5 -q X M I m Plle e? 0s m s 1 f n f f f f f f i n f f f f c n f f f f f f f f f f f cn f cn f f cn f f f f f f f f f f c n f f f f f m f f f f f in in in f f f f f i n f f f m in in in m g & i ia I JfflSlllllls :li I In l l I I Q

24 3 g 1 3. S I e I III u % P3 T f T f IT) U") Tf" T f "d* T f Tf" T f Xf" Tf" ^3" T f ^3- IT) *st m T t e n T t m m c S ^ T t *n s ^ ' c o ^ t ' s f ' T t ' c t n ^ t O st sf tt Tt tn 'tf if't* St St si" m Tt Tt \n Tt Tj" Tt sf Tt Tf (T) Tt Tf" Tt Tt <t Tt Tt "(f HI ^ Tt Tf Tf Tt Tt Tg- Ttm^t in sf tr>rf st "V ^ Tt "StTfrf "Stxt -y- Tf st Tt Tt Tt sfinrt m in in Tf Cti ir> T t ^ f t t T t ' ^ t ' s t m m ' ^ t m tn rf st «n m Tt in m in Tt 3 g 1 1 I O ' k 6 «" 8 g #1 I U 1 fa o fe 05 y mymymmmyy y y y M y y y yyyy Tt r t in in -st Tt x t x t x t x t ro x t x t m x t x t x t T t T f r f I t -ST 'd* Xt x f x f x t t n xj- xt* xh x f T T x t xt xt xh xt xf xh xh <n x t x t x t x t x t x t x t i n x t xf c n x t c n x f m c n c N x t x t m xtxtxtxtxtxtcnm xt x t xh xh m x t x f xf x t x t x f x t x f <" " f x f m x f m x t in x t x t x f Xt xf X f xf X f Xf xf Xf xf xf xf xf xf xf in xf in in in xf in x t x f x t x t x t x t x t m x t m in xf xf in in xf m in m xf x f ^ ^ x f x f x f x f B-2 0 %-ns s s O fa fa x f x f in in x f x f xf x f x f x f Xf x f x f x f x f x f x f x f xf in x f x f x f x f x f x f x f i n x f xf xf xf co xf xf m xf xf xf xf xf Xf CO Xf Xf Xf Xf Xf ef 'd* xf xf co i f x f ^ - xf xf xf xf xf xf xf xf in xf in in m xf in x f x f x f x f x f x f x f i n x f in m xf xf in m xf m, in in xf Cti f I o B5 U1 III, l l llfllm &% e e e ii g& y,u aril ill fl 1g a g g f f i g g g i s i a a gi

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26 APPENDIX C RESULTS OF A THREE YEAR AIR MASS-BASED SEASONAL (SUMMER AND WINTER) SYNOPTIC CLIMATOLOGY FOR SOUTH AFRICA 1, INTRODUCTION The results of the three year air mass-based synoptic climatology established for each of the nine rawisonde stations for summer (December, January, February) and winter (June, July, August) seasons are presented in this Appendix. The percentage of winter and summer days for each station, for which sufficient data was available to enable statistical analysis and classification, is presented in Table C.l. Although the autumn and spring seasons were initially included in the assessment, the analysis of these periods was terminated since the use of upper air meteorological data recorded at twelve hour intervals proved inadequate to accurately reflect the rapid transition between circulation patterns characteristic of these periods with the technique selected. The synoptic types identified as influencing each of the nine stations during summer and winter months are presented. The meteorological characteristics of synoptic types are discussed separately for coastal and inland stations due to the frequently distinctly different vertical profiles which characterise the atmosphere of coastal and inland regions under the influence of a particular synoptic type. The synoptic trends noted for each station are perceived to be representative of the region in which the station occurs, viz. Pietersburg, Irene,, Bloemfontein, Bethlehem and Upington represent the Northern, Central, Southeastern, Eastern and Western Plateau respectively; whereas Cape Town, Springbok, Port Elizabeth and Durban represent the Southern, Western, Southeastern, and Eastern Coasts respectively. Table C.l: Total number of days for which data were available for use in the establishment of the seasonal synoptic climatology. STATION: No. (PERCENTAGE) DAYS USED IN ANALYSIS WINTER SUMMER Bethlehem 213 (77.2%) 192(71.1%) Bloemfontein 188(68.1%) 179 (66.3%) Cape Town 232 (84.1%) 218 (80.7%) Durban 208 (75.4%) 180 (66.7%) Irene 182 (66%) 206 (76.3%) Pietermaritzburg 206 (74.6%) 198 (73.3%) Pc'i Elizabeth 245 (88.8%) 80 (29.6%)(a) Spiingbok 174 (63%) 157 (58%) Upington 197 (71.4%) 202 (74.8%) a) Due the magnitude of missing data in December and January months, only February months were used in the analysis for PE. Surface pressure and vertical profiles of temperature, humidity and zonal and meridional wind components are illustrated for each synoptic type at each station for both winter and summer (Figures C.l - C.18). Tables indicating the frequency of occurrence and persistence (including the average and maximum number of days over which synoptic patterns exits) of each of the C-1