ATMOSPHERIC IMPACT REPORT: APPLICATION FOR POSTPONEMENT OF THE MINIMUM EMISSION STANDARDS AT THE AEL MINING SERVICES: MODDERFONTEIN INDUSTRIAL COMPLEX Project done on behalf of: AEL Mining Services Limited
Project Compiled by: N Grobler R von Gruenewaldt
Project Manager H Liebenberg-Enslin
Report No: 14AEL01 | Date: February 2015
Address: 480 Smuts Drive, Halfway Gardens | Postal: P O Box 5260, Halfway House, 1685 Tel: +27 (0)11 805 1940 | Fax: +27 (0)11 805 7010
www.airshed.co.za
Report Details
Project Name
Atmospheric Impact Report: Application For Postponement Of The Minimum Emission Standards At The AEL Mining Services: Modderfontein Industrial Complex
Client
AEL Mining Services Limited
Report Number
14AEL01
Report Version
Final
Date
February 2015 Nick Grobler, BEng (Chem), BEng (Hons) (Env) (University of Pretoria)
Prepared by
Hanlie Liebenberg-Enslin, PhD (University of Johannesburg)
Notice
Airshed Planning Professionals (Pty) Ltd is a consulting company located in Midrand, South Africa, specialising in all aspects of air quality, ranging from nearby neighbourhood concerns to regional air pollution impacts as well as noise impact assessments. The company originated in 1990 as Environmental Management Services, which amalgamated with its sister company, Matrix Environmental Consultants, in 2003.
Declaration
Airshed is an independent consulting firm with no interest in the project other than to fulfil the contract between the client and the consultant for delivery of specialised services as stipulated in the terms of reference.
Copyright Warning
Unless otherwise noted, the copyright in all text and other matter (including the manner of presentation) is the exclusive property of Airshed Planning Professionals (Pty) Ltd. It is a criminal offence to reproduce and/or use, without written consent, any matter, technical procedure and/or technique contained in this document.
Revision Record Version
Date
Section(s) Revised
Summary Description of Revision(s)
Draft
January 2015
Entire report
Technical and editorial review
Final
February 2015
Entire report
Incorporation of changes and addition of modelling scenarios
Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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Preface AEL Mining Services’ operations at the Modderfontein Industrial Complex are required to comply with the Minimum Emission Standards, which came into effect in terms of Section 21 of the National Environment Management: Air Quality Act (Act No 39 of 2004) on 22 November 2013. These standards require the operations to comply with the “existing plant” limits by 1 April 2015, and with more stringent “new plant” limits by 1 April 2020. AEL Mining Services intends submitting an application for extension of the compliance timeframes. In support of the submissions and to fulfil the requirements for these applications stipulated in the Air Quality Act and the Minimum Emission Standards, air quality studies are required to substantiate the motivations for the extension. Operations at the AEL Mining Services Modderfontein site include the manufacture of nitrogen based chemicals, bulk explosives and initiating systems. The AEL Mining Services operations are situated in the Modderfontein Industrial Complex, which comprises mainly industrial and commercial land, some of which is currently vacant land owned by AECI (the parent company of AEL Mining Services). Sensitive receptors in proximity to the operations include the residential areas of Thornhill Estate, Thornhill Manor, Lakeside, Linbro Park, Greenstone Hill, Esther Park, Edleen, Terenure (and Kempton Park West), Birch Acres, Chloorkop, Klipfontein View and other parts of Edenvale, Tembisa and Kempton Park. Airshed Planning Professionals (Pty) Ltd was appointed by AEL Mining Services Limited to provide independent and competent services for the compilation of an Atmospheric Impact Report as set out in the Regulations and detailing the results of dispersion modelling simulations. The tasks undertaken consisted of: 1. Preparing meteorological data for inclusion in a suitable atmospheric dispersion model; 2. Preparing emissions inventory for the current emissions from the AEL Mining Services Modderfontein operations; 3. Simulating dispersion of particulate, sulphur dioxide, oxides of nitrogen and ammonia emissions and calculating ground level concentrations for various averaging periods, including hourly, daily and annual averages; 4. Reporting incremental concentration plots on base maps of the region. If the NAAQS limit values are exceeded, the frequency of exceedance will also be reported at selected locations; 5. Comparing predicted ground level pollutant concentrations with values measured at AEL Mining Services Modderfontein Station; and, 6. Preparing a comprehensive report with a. A summary of all baseline monitoring results, b. Emissions inventory, c. Model input parameter description, d. Model results, e. Discussion of model results, with specific reference to the motivation for the AEL postponement. Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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Table of Contents 1
2
Enterprise Details ........................................................................................................................................... 8 1.1
Description of Surrounding Land Use (within 5 km radius) .................................................................... 9
1.2
Atmospheric Emission Licence and other Authorisations ...................................................................... 9
Nature of the Process................................................................................................................................... 11 2.1
Listed Activities .................................................................................................................................... 11
2.2
Process Description............................................................................................................................. 11
2.3
Unit Processes .................................................................................................................................... 14
3
Technical Information ................................................................................................................................... 16
4
Atmospheric Emissions ................................................................................................................................ 19
5
4.1
Point Source Emissions ....................................................................................................................... 19
4.2
Fugitive Emissions............................................................................................................................... 26
4.3
Emergency Incidents ........................................................................................................................... 28
Impact of Enterprise on the Receiving Environment .................................................................................... 29 5.1
Ambient Air Quality Impact Assessment Criteria ................................................................................. 29
5.1.1
Listed Activities and Minimum Emission Standards ........................................................................ 29
5.1.2
Controlled Emitters and Emission Standards .................................................................................. 31
5.1.3
National Ambient Air Quality Standards for Criteria Pollutants ........................................................ 32
5.1.4
Screening Criteria for NH3 ............................................................................................................... 32
5.2
Atmospheric Dispersion Potential ........................................................................................................ 34
5.2.1
Local wind field................................................................................................................................ 34
5.2.2
Ambient Temperature...................................................................................................................... 36
5.2.3
Precipitation .................................................................................................................................... 36
5.3
Air Quality Monitoring Data .................................................................................................................. 37
5.4
Atmospheric Dispersion Modelling Methodology ................................................................................. 43
5.5
Dispersion Modelling Results .............................................................................................................. 47
5.5.1
NOx emissions ................................................................................................................................. 47
5.5.2
SO2 emissions ................................................................................................................................. 51
5.5.3
PM10 emissions ............................................................................................................................... 53
5.5.4
NH3 emissions ................................................................................................................................. 57
5.5.5
Comparison of Measured and Predicted Concentrations ................................................................ 61 Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex
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5.5.6 5.6
Conclusion ...................................................................................................................................... 62 Analysis of Emissions’ Impact on the Environment ............................................................................. 62
6
Complaints ................................................................................................................................................... 62
7
Current or planned air quality management interventions ............................................................................ 63 7.1
Air Quality Improvements to date ........................................................................................................ 63
7.2
Future Air Quality Management Interventions ..................................................................................... 63
7.2.1
Stills................................................................................................................................................. 63
7.2.2
PETN Plant ..................................................................................................................................... 63
7.2.3
ANS 1 and 2 Plants and ANNSER Plant ......................................................................................... 64
7.2.4
No. 3 Ammonium Nitrate Evaporator .............................................................................................. 64
7.2.5
No. 9 Nitric Acid Plant ..................................................................................................................... 64
7.2.6
No. 11 Nitric Acid Plant ................................................................................................................... 64
8
Compliance and enforcement history ........................................................................................................... 71
9
Additional Information................................................................................................................................... 71 9.1
References .......................................................................................................................................... 71
10
Annexure A................................................................................................................................................... 72
11
Annexure B................................................................................................................................................... 73
12
Annexure C – Complaints Register .............................................................................................................. 74
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List of Tables Table 1-1: Enterprise details ................................................................................................................................... 8 Table 1-2: Contact details of responsible person .................................................................................................... 8 Table 1-3: Location and extent of the plant ............................................................................................................. 8 Table 2-1: Listed activities..................................................................................................................................... 11 Table 2-2: Controlled Emitter ................................................................................................................................ 11 Table 2-3: List of unit processes considered as listed activities under NEMAQA ................................................. 14 Table 2-4: List of non-listed activity unit processes ............................................................................................... 14 Table 2-5: Location of unit processes ................................................................................................................... 15 Table 3-1: Raw materials used ............................................................................................................................. 16 Table 3-2: Production Rates ................................................................................................................................. 17 Table 3-3: By-Product Production Rates ............................................................................................................... 17 Table 3-4: Materials used in energy sources ........................................................................................................ 17 Table 3-5: Appliances and abatement equipment control technology ................................................................... 18 Table 4-1: Point source parameters ...................................................................................................................... 19 Table 4-2: Point source emission rates during normal operating conditions ......................................................... 21 Table 4-3: Point source current emissions monitoring .......................................................................................... 22 Table 4-4: Point Source Maximum Emission Rates during Start-up, Maintenance and/or Shut-down.................. 24 Table 4-5: Fugitive emission source parameters .................................................................................................. 26 Table 4-6: Fugitive emission rates ........................................................................................................................ 27 Table 4-7: Basis of calculation for fugitive emission rates..................................................................................... 28 Table 5-1: Listed activity – Subcategory 7.2 – Production of Acids ...................................................................... 29 Table 5-2: Listed activity – Subcategory 7.3 – Production of Chemical Fertilizer.................................................. 30 Table 5-3: Listed activity – Subcategory 8.3 – Burning Grounds .......................................................................... 30 Table 5-4: Controlled emitter – Solid fuel-fired small boiler................................................................................... 31 Table 5-5: National Ambient Air Quality Standards for criteria pollutants ............................................................. 32 Table 5-6: International guidelines for ammonia ................................................................................................... 33 Table 5-7: Long-Term Average Monthly Rainfall for the Period 1951 – 1984 (Schulze, 1986). ............................ 37 Table 5-8: Summary of air quality monitoring data at the AEL Mining Services Modderfontein monitoring station (2010 – 2014)........................................................................................................................................................ 37 Table 5-9: Meteorological Data Availability ........................................................................................................... 44 Table 5-10: NOx emission sources that are in exceedance of the MES. ............................................................... 47 Table 5-11: Simulated NOx concentrations at sensitive receptor locations. .......................................................... 48 Table 5-12: Simulated SO2 concentrations at sensitive receptor locations. .......................................................... 51 Table 5-13: PM10 emission sources that are in exceedance of the 2015 MES. .................................................... 53 Table 5-14: Simulated PM10 concentrations at sensitive receptor locations.......................................................... 54 Table 5-15: NH3 emission sources that are in exceedance of the 2015 MES. ...................................................... 57 Table 5-16: Simulated NH3 concentrations at sensitive receptor locations. .......................................................... 58 Table 5-17: Comparison of Measured and Predicted Concentrations .................................................................. 61 Table 8-1: The AEL Mining Services Modderfontein operations’ compliance with the NEM: AQA. ...................... 71 Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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List of Figures Figure 1-1: Location and Surrounding Land Use .................................................................................................. 10 Figure 2-1: Process Flow Diagram........................................................................................................................ 13 Figure 5-1: Period average and diurnal wind roses (On-site data, 2010 - 2014)................................................... 35 Figure 5-2: Seasonal wind roses (On-site data, 2010 - 2014)............................................................................... 35 Figure 5-3: Diurnal temperature profile (On-site data, 2010 - 2012) ..................................................................... 36 Figure 5-4: NOx polar plot for the AEL Mining Services Modderfontein monitoring station .................................. 39 Figure 5-5: Diurnal NOx profile for the AEL Mining Services Modderfontein monitoring station ........................... 39 Figure 5-6: SO2 polar plot for the AEL Mining Services Modderfontein monitoring station .................................. 40 Figure 5-7: Diurnal SO2 profile for the AEL Mining Services Modderfontein monitoring station ........................... 40 Figure 5-8: PM10 polar plot for the AEL Mining Services Modderfontein monitoring station ................................. 41 Figure 5-9: Diurnal PM10 profile for the AEL Mining Services Modderfontein monitoring station ......................... 41 Figure 5-10: PM2.5 polar plot for the AEL Mining Services Modderfontein monitoring station .............................. 42 Figure 5-11: Diurnal PM2.5 profile for the AEL Mining Services Modderfontein monitoring station ....................... 42 Figure 5-12: Simulated highest hourly NOx concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 49 Figure 5-13: Simulated highest hourly NOx concentration due to AEL Mining Services Modderfontein operations in compliance with 2020 MES. .............................................................................................................................. 49 Figure 5-14: Simulated annual average NOx concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 50 Figure 5-15: Simulated annual average NOx concentration due to AEL Mining Services Modderfontein operations in compliance with 2020 MES. .............................................................................................................................. 50 Figure 5-16: Simulated highest hourly SO2 concentration due to AEL Mining Services Modderfontein operations. .............................................................................................................................................................................. 52 Figure 5-17: Simulated highest daily SO2 concentration due to AEL Mining Services Modderfontein operations. 52 Figure 5-18: Simulated annual average SO2 concentration due to AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 53 Figure 5-19: Simulated highest daily PM10 concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 55 Figure 5-20: Simulated highest daily PM10 concentration due to AEL Mining Services Modderfontein operations in compliance with 2020 MES. .................................................................................................................................. 55 Figure 5-21: Simulated annual average PM10 concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 56 Figure 5-22: Simulated annual average PM10 concentration due to AEL Mining Services Modderfontein operations in compliance with 202 MES. .............................................................................................................. 56 Figure 5-23: Simulated highest hourly NH3 concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 58 Figure 5-24: Simulated highest hourly NH3 concentration due to AEL Mining Services Modderfontein operations in compliance with the 2020 MES. ........................................................................................................................ 59 Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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Figure 5-25: Simulated highest daily NH3 concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 59 Figure 5-26: Simulated highest daily NH3 concentration due to AEL Mining Services Modderfontein operations in compliance with the 2020 MES. ............................................................................................................................ 60 Figure 5-27: Simulated annual average NH3 concentration due to current AEL Mining Services Modderfontein operations. ............................................................................................................................................................ 60 Figure 5-28: Simulated annual average NH3 concentration due to AEL Mining Services Modderfontein operations in compliance with the 2020 MES. ........................................................................................................................ 61 Figure 7-1: Roadmap to compliance for the Stills ................................................................................................. 65 Figure 7-2: Roadmap to compliance for the PETN Plant ...................................................................................... 66 Figure 7-3: Roadmap to compliance for ANS 1 and 2 and the ANNSER Plant ..................................................... 67 Figure 7-4: Roadmap to compliance for No. 3 Ammonium Nitrate Plant including the evaporator ....................... 68 Figure 7-5: Roadmap to compliance for No. 9 Nitric Acid Plant ............................................................................ 69 Figure 7-6: Roadmap to compliance for No. 11 Nitric Acid Plant .......................................................................... 70
Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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Atmospheric Impact Report
1
ENTERPRISE DETAILS
The details of the AEL Mining Services Modderfontein operations are summarised in Table 1-1. The contact details of the responsible person are provided in Table 1-2. The surrounding land use and communities are shown in Table 1-3. Table 1-1: Enterprise details Enterprise Name
AEL Mining Services Limited
Trading as
AEL Mining Services Limited
Company Registration Number Registered Address
1973/008610/06 AECI Place, 1st Floor, 24 The Woodlands, Woodlands Drive, Woodmead, Sandton, Republic of South Africa
Telephone Number (General)
(011) 606 0000
Industry Type/Nature of Trade
Manufacture of nitrogen based chemicals, bulk explosives and initiating systems.
Land Use Zoning as per Town Planning Scheme
Industrial 1,2 and 3
Table 1-2: Contact details of responsible person Responsible Person
Ellen van Dongen
Telephone Number
011 606 0000
Cell Number
082 813 9611
Fax Number
011 605 0843
Email Address
[email protected]
After Hours Contact Details
082 813 9611
Table 1-3: Location and extent of the plant Physical Address of the Plant
Modderfontein Industrial Complex, Standerton Avenue, Modderfontein.
Description of Site (Where no Street Address) Coordinates of Approximate Centre of Operations
Latitude: 28°10’18” Longitude:26°05’27”
Extent
11 km²
Elevation Above Sea Level
1639 m
Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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Province
Gauteng
Metropolitan/District Municipality
City of Johannesburg
Local Municipality
City of Johannesburg
Designated Priority Area
1.1
N/A
Description of Surrounding Land Use (within 5 km radius)
The land use surrounding the Modderfontein Industrial Complex comprises mainly industrial, commercial and residential land some of which is currently vacant land which is owned by AECI. Industrial areas include Chloorkop, Sebenza, Spartan and Croyden. Commercial areas include Founders View, Longmeadow Business Estate and Greenstone. Residential areas include Thornhill Estate, Thornhill Manor, Lakeside, Linbro Park, Greenstone Hill, Esther Park, Edleen, Terenure (and Kempton Park West), Birch Acres, Chloorkop, Klipfontein View and other parts of Edenvale, Tembisa and Kempton Park. There are a number of schools and clinics in the vicinity of the Modderfontein Industrial Complex as shown in Figure 1-1.
1.2
Atmospheric Emission Licence and other Authorisations
The following authorisations, permits and licences related to air quality management are applicable:
Air Pollution Prevention Act (APPA) Registration Certificates: o 135/11 – 4 – Nitric Acid Processes o 135/14 – 4 - Nitric Acid Processes o 135/22 – 4 Nitric Acid Processes o 135/34 - 4 – Nitric Acid Processes o 135/12 – 23 – Lead Processes o 135/8 -29 – Power Generation Processes o 135/9 – 29 - Power Generation Processes o 135/31 – 39 – Waste Incineration Processes o 135/32 – 39 - Waste Incineration Processes o 135/33 – 39 - Waste Incineration Processes o 135/35 – 39 - Waste Incineration Processes o 135/4 – 43 – Ammonia Processes o 135/5 – 43 – Ammonia Processes o 135/10 – 43 – Ammonia Processes o 135/30 – 43 – Ammonia Processes
Atmospheric Emission License: o AEL (AQ/REGE/AEL003)
Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01 Draft
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Figure 1-1: Location and Surrounding Land Use Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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2
NATURE OF THE PROCESS 2.1
Listed Activities
A summary of listed activities currently undertaken at the AEL Mining Services Modderfontein operations is provided in Table 2-1., with the controlled emitter source listed in Table 2-2. Table 2-1: Listed activities Listed Activity
Listed Activity Name
Description of the Listed Activity
Number The production, bulk handling and or use in manufacturing of hydrofluoric, hydrochloric, nitric and sulphuric acid (including oleum) in concentration
7.2
Production of acids
exceeding 10%; also processes in which oxides of sulphur are emitted through the production of acid sulphites of alkalis or alkaline earths or through the production of liquid sulphur or sulphurous acid and secondary production of hydrochloric acid through regeneration. Application: All installations producing, hjandling and or using more than 100 tons per annum of any of the listed compounds (Excluding metallurgical processes related activites regulated under category 4)
Production of chemical
7.3
fertilizer
The production of superphosphates, ammonium nitrate, ammonium phosphates and or ammonium sulphate and their processing into fertiliser mixtures (NPK mixtures). Application: All installations producing and or processing more than 10 tons per month. Facilities where waste material from the manufacture of explosives and
8.3
Burning grounds
contaminated explosive packaging material are destroyed. Application: All installations disposing of more the 100 kg of material per week.
Table 2-2: Controlled Emitter Controlled Emitter
Solid fuel-fired small boiler
2.2
Description Solid fuel (excluding biomass) combustion installations used primarily for steam raising or electricity generation. Application: All installations with design capacity less than 50 MW heat input per unit, based on the lower calorific value of the fuel used. The AEL Fluidized Bed Boiler has a heat input of 34 MW. The No.2 boiler has a heat input of 31 MW. Both of these boilers are less than 50 MW and are considered controlled emitters.
Process Description
Liquid ammonia is received at Nitrates Storage and Distribution and is offloaded into either LP5 ammonia storage tank or sent directly to the consumer plants. Aqueous ammonia solution is produced at Storage and Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Distribution. Incidental sources would be ammonia gas escaping from the offloading and loading of ammonia and the production of aqueous ammonia solution. Emergency releases of ammonia through one of two flares are also possible. Liquid ammonia is pumped to two nitric acid plants (No 9 and No 11) where the ammonia is catalytically oxidised and then absorbed to form nitric acid. Both plants have stacks for the release of tail gas. The air emissions are made up of mostly nitrogen oxides and nitrogen with some residual oxygen. During the storage of nitric acid some fuming might occur. Liquid ammonia is sent to the ammonium nitrate solution plants (ANS1 and ANS2) along with some of the nitric acid to react and form ammonium nitrate. The ammonium nitrate produced is in the form of a 92% concentration solution. During the process heat is evolved and steam is generated. The steam contains unreacted ammonia and entrained ammonium nitrate which is then fed to the ANSSER (Ammonium Nitrate Solution Stack Emission Reduction) plant where the steam is condensed and the ammonia recovered. The ammonium nitrate solution generated from the ANSSER plant is re-used in the process. During start-up the ANS plant emissions are vented to atmosphere prior to being routed into the ANSSER plant. Some of the ANS is sent to the prilling plants (No 3 and 4) to be prilled for the production of porous prill ammonium nitrate (PPAN). The process consists of spraying the ANS from the top of the prilling towers where the falling droplets are cooled and solidified by the air draft from the bottom of the tower. The solidified droplets are dried in rotating drying drums. The spraying process creates fine ammonium nitrate entrainment in the air that exits at the top of the prill tower. During the drying process fine ammonium nitrate entrainment in the air also occurs and this is scrubbed prior to release to atmosphere. A DAF (dissolved air flotation) plant is used to handle and treat the effluent streams from Nitrates. Part of the DAF plant is an evaporator (Recycle evaporator) that is used to concentrate the effluent to make it suitable for sale. The evaporator discharges into atmosphere, but most of it reports as fall-out within the plant footprint. The prills from the prilling plants are sent to the Bagging Shed and Bulk Store where the product is stored in bulk, bagged and loaded for transport. Some ammonium nitrate dust generation might occur during the handling of the prill. Some of the ANS is sent to the Central Bulk Emulsion Plant (CBEP) to produce emulsion explosive. This plant does not have any air emissions. The remaining ANS is stored and loaded for transport at the Tank Farm. This Tank Farm has no air emissions other than steam from the ANS storage tanks. At the Still plant the 60% nitric acid produced by the nitric acid plants is concentrated to 96% strength for use in explosives manufacturing. Through azeotropic distillation the nitric acid is concentrated. During the process some nitrogen oxide gas is generated and this is scrubbed by the NOx scrubber. The scrubbed gas is then discharged into atmosphere. Some of the Ammonium Nitrate porous prill is sent to the Anfex plant where it is mixed with fuel oil to form an explosive that is then bagged and transported. This plant has a small amount of fuel phase vapour generation within the building. Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Steam is used mainly for heating and to drive the steam turbines in the Nitric Acid plants and is generated by either of two boilers. The boiler commonly used is the Fly Ash Boiler (FAB) and derives its name from the fact that the boiler was designed to use fly ash. The FAB flue gas is filtered in a bag house before being released through the stack. The No 2 boiler is smaller than the FAB and is used as a back-up boiler. The flue gas passes through a multiple inclined cyclone prior to being discharged to atmosphere. The manufacture of pentaerythritoltetranitrate (PETN) involves the nitration of pentaerythritol with the 96% nitric acid. The spent nitric acid (80% concentration) is sent to the Still tank farm where it is mixed with the Still’s scrubber solution to produce a saleable product. The manufacture of PETN operates under an explosive licence issued by the Department of Labour under the Explosives Act. Scrap lead from the various explosive manufacturing production units is placed in a temperature controlled cast iron melting pot and heated to 350°C. The molten lead so produced is drawn off and placed in a mould to solidify. The dross consisting of all impurities is removed and sent to a hazardous waste site.
INPUT PROCESS OUTPUT
Ammonia (rail tankers)
OBJECTIVE: TO CONVERT AMMONIA INTO NITRIC ACID, AMMONIUM NITRATE SOLUTION, AMMONIUM NITRATE PRILL, ANFEX AND EMULSION AS PER OUR CUTOMER'S REQUIREMENTS
Lagoon
Ammonia Storage and Distribution Ammoni a
Anhydrous Ammonia Refridge grade
ANS Blending Tanks
25 % Ammonia Solution
88 % ANS Solution Explosives Fertilizers Speciallised Use
Tank Farm 88 % ANS Solution
Fuel Oil / waste Oil
ANSSER
Nitric Acid Plants No 9 & No 11 NA
Ammonium Nitrate Solution Plants No 1 and 2 ANS 92 % Solution
Emulsion Plant
Waste / Crystallized Emulsion
60 % Nitric Acid
Underground Emulsion UBS
Ammonium
Ammonium
Nitrate Ammoniu Plants m Nitrate No 3 and No Plants
Nitrate
No. 4 Plant Stills Plant
Base Emulsion Surface Emulsion P100
Melting & Disolving Tank
4PPAN
98 % Sulphuric Acid
Liquid Fertilizers
Normal bulk density
Porous Prill
Low bulk density
Ammonium Nitrate ANFLOW
Uncoated Coated
96 % Nitric Acid Fuel Oil / Waste Oil
Sulphuric Acid
ANFEX Anfex Plant Plant
ANFEX
RAW MATERIALS
PRODUCTS
PETN Plant
80 % Nitric Acid
PETN
Figure 2-1: Process Flow Diagram Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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2.3
Unit Processes
Unit process considered listed activities under the National Environmental Management Air Quality Act (NEMAQA) are summarised in Table 2-3. Other unit processes that may result in atmospheric emission which are, however, not considered listed activities are summarised in Table 2-4. The location of the unit processes are shown in Table 2-5. Table 2-3: List of unit processes considered as listed activities under NEMAQA Unit Process Function
Batch or Continuous Process
Listed Activity Subcategory
ANS 1
Production of ammonium nitrate solution
Continuous
7.3
ANS 2
Production of ammonium nitrate solution
Continuous
7.3
No. 9 Nitric Acid
Production of nitric acid
Continuous
7.2
No. 11 Nitric Acid
Production of nitric acid
Continuous
7.2
No. 3 Ammonium Nitrate
Production of ammonium nitrate
Continuous
7.3
No. 4 Ammonium Nitrate
Production of ammonium nitrate
Continuous
7.3
Stills
Production of concentrated nitric acid
Continuous
7.2
IC 100 burning ground
Destruction of explosive waste by open burning
Batch
8.3
Packaged Explosive burning ground
Destruction of explosive waste by open burning
Batch
8.3
Cordtex burning ground
Destruction of explosive waste by open burning
Batch
8.3
Pentolite burning ground
Destruction of explosive waste by open burning
Batch
8.3
PETN nitration
Production of PETN primary explosive
Batch
7.2
Name of the Unit Process
Table 2-4: List of non-listed activity unit processes Name of the Unit Process
Unit Process Function
Batch or Continuous Process
ANSSER plant
Plant condenses the steam produced by the ANS plants and recovers the unreacted ammonia and ammonium nitrate.
Continuous
Fluidized Bed Boiler
Production of steam
Continuous
No. 2 Boiler
Production of steam
Continuous
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Table 2-5: Location of unit processes Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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3
TECHNICAL INFORMATION
Raw material consumption and production rates are tabulated in Table 3-1 and Table 3-2 respectively. Information regarding the materials used as energy sources is provided in Table 3-4. Pollution abatement technologies employed at AEL Mining Services Modderfontein operations’ listed activities, and technical specifications thereof, are provided in Table 3-5. Table 3-1: Raw materials used Raw Material Type
Design Consumption Rate
Rate Unit
Anhydrous ammonia (as 100%)
600
tons/day
60% nitric acid (as 100%)
1129
tons/day
92% ANS (as 100%)
730
tons/day
Coal (FAB)
130
tons/day
Coal (No.2)
115
tons/day (when operational)
Camp A 2000 kg Explosive and explosive contaminated waste (IC 100 burning ground)
Camp B 500 kg Camp C 400 kg
kg/day
(determined by the explosive license issued under the Explosives Act) Explosive and explosive contaminated waste (Packaged Explosive burning ground)
Explosive and explosive contaminated waste (Cordtex burning ground)*
Explosive and explosive contaminated waste (Pentolite burning ground)
PETN Nitric acid (96%)
SLF7 1500 kg SLF6 630 kg (determined by the explosive license issued under the
kg/day
Explosives Act) 150 kg (determined by the explosive license issued under the Explosives Act)
kg/day
250 kg (determined by the explosive license issued under the Explosives Act) 12 tons Nitric Acid 2 tons Pentaerythritol
kg/day
tons/day
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Table 3-2: Production Rates Product Name
Design Production Capacity (Quantity)
Units (Quantity/Period)
60% nitric acid (as 100%)
1020
tons/day
92% ANS (as 100%)
1400
tons/day
Ammonium nitrate porous prill
730
tons/day
Ammonium nitrate dense prill
400
tons/day
93%-99% nitric acid (as 100%)
16
tons/day
68%-71% sulphuric acid
68
tons/day
Steam (FAB)
950
tons/day
Steam (No.2 Boiler)
820
tons/day
PETN
3996
kg/day
By-Product Name
Design Production Capacity (Quantity)
Units (Quantity/Period)
68%-71% sulphuric acid (Stills)
68
ton/day
Ash (FAB flyash)
24.6
ton/day
Ash No.2 (coarse ash)
21
ton/day
Spent acid (PETN)
7.43
ton/day
Table 3-3: By-Product Production Rates
Table 3-4: Materials used in energy sources Materials for Energy
Sulphur Content of the Material (%)
Ash Content of Material (%)
Design Consumption Rate (Quantity)
Units (Quantity/Period)
Coal (FAB)
0.7%
20%
130
ton/day
Coal (No.2)
0.7%
20%
115
ton/day
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Table 3-5: Appliances and abatement equipment control technology Associated Unique Stack ID
Abatement Equipment Name and Model
Abatement Equipment Technology Type
ANPP3Rotopre
Type W Rotoclone – Model APC-3-512-Q
Wet centrifugal Collector Fan with water sprays
ANPP3Rotodrier
Type W Rotoclone – Model APC-3-512-Q
Wet centrifugal Collector Fan with water sprays
ANPP3Rotocooler
Type W Rotoclone – Model APC-3-512-Q
Wet centrifugal Collector Fan with water sprays
ANPP4Scrubber
Centrifugal scrubber with water sprays
ANS1
Brink Filter Unit with demister pads
Monsanto Demister Pads
ANS1
Packed bed scrubber unit with circulating water flow
Original equipment manufacturer –
ANS2
Brink Filter Unit with demister pads
Monsanto Demister Pads
ANS2
Packed bed scrubber unit with circulating water flow
Original equipment manufacturer
ANS2
Monsanto spray panels with circulating acidified weak ammonium nitrate solution
Monsanto Original equipment manufacturer –
ANSSER
Plate Heat Exchanger with acidified weak ANS solution circulating spray
Absorption and neutralization Process
Stills
NOx absorbed Nitric acid column
Original Equipment Manufacturer
FAB
Bag Filter Unit
Bag Filter Unit
2Boiler
Original Equipment Manufacturer
Cyclone
PETNboiling
Boiling Tube Condenser unit
In house design by CIL Canada
Centrifugal scrubber with water sprays
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4
ATMOSPHERIC EMISSIONS
4.1
Point Source Emissions
The establishment of a comprehensive emission inventory formed the basis for the assessment of the air quality impacts from AEL Mining Services Modderfontein operations on the receiving environment. Table 4-1: Point source parameters Latitude
Longitude
Height of
Actual Gas
Actual Gas
Actual Gas
Height Above
Diameter at
Nearby Building (m)
Stack Tip / Vent Exit (m)
Exit Temperature (°C)
Volumetric Flow (m³/hr)
Exit Velocity (m/s)
Unique Stack ID
Source Name
(decimal degrees)
(decimal degrees)
Release Above Ground (m)
NA9
No. 9 Nitric Acid stack
-26.0955
28.1744
67
55
0.762
160
58 680
35.7
NA11
No. 11 Nitric Acid stack
-26.0972
28.1738
63
40
1.42
160
85 000
31.2
ANPP3Prill
No. 3 Ammonium Nitrate Porous Prill: Prilling tower
-26.0941
28.1752
50
40
1.219
41
329 400
9.8
-26.0941
28.1752
63
56
0.375
140
5 760
13.2
-26.0941
28.1752
17
0
35
25 920
11.9
-26.0941
28.1752
17
0
31
23 400
10.7
-26.0941
28.1752
17
0
29
31 680
14.5
ANPP3Evap
No. 3 Ammonium Nitrate Porous Prill: Evaporator No. 3 Ammonium Nitrate
ANPP3Rotopre
ANPP3Rotodrier
ANPP3Rotocooler
Porous Prill: Pre-drier rotoclone No. 3 Ammonium Nitrate Porous Prill: Drier rotoclone No. 3 Ammonium Nitrate Porous Prill: Cooler rotoclone
0.78 x 0.78 (square duct) 0.78 x 0.78 (square duct) 0.78 x 0.78 (square duct)
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Unique Stack ID
Source Name
ANPP4Prill
No. 4 Ammonium Nitrate Porous Prill: Prilling tower
ANPP4Scrubber
No. 4 Ammonium Nitrate Porous Prill: Scrubber
Latitude
Longitude
(decimal degrees)
(decimal degrees)
-26.0947
28.1741
-26.0947
Height of Release
Actual Gas Exit
Diameter at
Nearby Building (m)
Stack Tip / Vent Exit (m)
52
28
5.8
29
163 800
1
28.1741
24
2
1.7
30
151 560
18.6
Above Ground (m)
Temperature (°C)
Actual Gas
Actual Gas Exit
Height Above
Volumetric Flow (m³/hr)
Velocity (m/s)
ANS1
No. 1 Ammonium Nitrate Solution stack
-26.0936
28.1738
30
10
0.5
97
10 440
15
ANS2
No. 2 Ammonium Nitrate Solution stack
-26.0944
28.1727
25
5
0.6
97
12 960
12.8
ANSSER
ANSSER plant stack
-26.0636
28.1738
5
0
0.08
35
320
13.8
Stills
Stills stack
-26.0950
28.1744
26
0
0.2
25
1 080
10.2
FAB
Flyash Boiler stack
-26.0847
28.1755
50
20
2
170
207 000
16.8
2Boiler
No. 2 Boiler Stack
-26.0833
28.1811
43.3
20
1.9
175
65 160
6.9
PETNboiling
PETN boiling tube stack
-26.0807
28.1746
11.5
7.5
0.1
21
0.0518
0.0002
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Table 4-2: Point source emission rates during normal operating conditions ID
Maximum Release Rate
Pollutant Name (mg/Nm³)
(mg/Am³)
(g/s)
Emission Hours
Type of Emissions(Continuous/Routine but Intermittent/Emergency Only)
NA9
NOx
360
226
3.6
24
Continuous
NA11
NOx
168
106
2.5
24
Continuous
ANPP3Prill
Particulates
56
43
1.6
24
Continuous
ANPP3Evap
Particulates
1 026
678
3.2
24
Continuous
ANPP3Evap
Ammonia
456
255
0.1
24
Continuous
ANPP3Rotopre
Particulates
20
17
0.1
24
Continuous
ANPP3Rotodrier
Particulates
45
40
0.2
24
Continuous
ANPP3Rotocooler
Particulates
8.2
7.4
0.1
24
Continuous
ANPP4Prill
Particulates
78
70
1.0
24
Continuous
ANPP4Scrubber
Particulates
43
38
0.6
24
Continuous
ANS1
Ammonia
10 180
7 511
18.5
Emissions from the ANS1 stack only when the ANSSER plant is offline
ANS2
Ammonia
2 430
1 792
5.4
Emissions from the ANS2 stack only when the ANSSER plant is offline
ANSSER
Ammonia
779
577
0.04
24
Continuous
Stills
NOx
3 396
3 111
1
24
Continuous
FAB
Particulates
22
42
0.8
24
Continuous
FAB
SO2
444
236
8.7
24
Continuous
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ID
Pollutant Name
Maximum Release Rate
Emission Hours
FAB
NOx
449
239
8.8
2Boiler
Particulates
1 128
580
15.1
2Boiler
SO2
794
408
9.6
2Boiler
NOx
371
180
4.9
PETNboiling
NOx
2 003 000
1 860 000
0.027
24
Type of Emissions(Continuous/Routine but Intermittent/Emergency Only) Continuous
The No. 2 Boiler is used as a back-up when the Flyash boiler is offline
24
Batch
Table 4-3: Point source current emissions monitoring ID
Emission Sampling / Monitoring Method
Sampling Frequency
Sampling Duration
Measured Parameters
NA9
Automatic Monitor
Every 5 seconds
Continuous
NOx, N2O
NA9
MDF 113 Revision C
12 hourly
10 minutes
NOx
NA11
Automatic Monitor
Every 5 seconds
Continuous
NOx, N2O
NA11
MDF 113 Revision C
12 hourly
10 minutes
NOx
ANPP3Prill
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
3 hours
ANPP3Evap
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
2 hours
ANPP3Rotopre
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
60 minutes
ANPP3Rotodrier
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
60 minutes
ANPP3Rotocooler
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
60 minutes
ANPP4Pril
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
2 hours
PM, NH3, HF
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ID
Emission Sampling / Monitoring Method
Sampling Frequency
Sampling Duration
Measured Parameters
ANPP4Scrubber
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
1 hour
ANS1
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
1 hour
ANS2
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
1 hour
ANSSER
ISO Standard 9096: 2003 MDF 700 / 2 (colorimetric) EPA Method 13 B
Bi-annually
2 hours
Stills
MDF 113 Revision C
12 hourly
10 minutes
NOx
FAB
ISO Standard 9096: 2003 EPA Method 6 EPA Method 3B EPA Method 7 C
Bi-annually
2 hours
PM, SO2, CO2, NO, CO
FAB
ISO Standard 9096: 2003
Continuous
Continuous
PM
2Boiler
SO Standard 9096: 2003 EPA Method 6 EPA Method 3B EPA Method 7 C
Bi-annually
2 hours
PM, SO2, CO2, NO, CO
2Boiler
ISO Standard 9096: 2003
Continuous
Continuous
PM
PETNboiling
EPA Method 7 C
Bi annually
2 hours
NOx
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Table 4-4: Point Source Maximum Emission Rates during Start-up, Maintenance and/or Shut-down
Unit Process
No. 3 Ammonium Nitrate – Rotoclones - Start Up, maintenance, shutdown, upset conditions
Description of Occurrence of Potential Releases
Equipment operational before plant on line, Maintenance only done when plant off line, Shutdown – product out of plant prior to
No. 4 Ammonium Nitrate – Maintenance, shutdown, upset conditions
Associated Amount of Emissions
Nil
shutdown, Upset conditions no effect on emissions
No. 3 Ammonium Nitrate – Prill Tower - Start Up, maintenance, shutdown, upset conditions
Pollutants and
Emissions from the prill tower as per normal operation
Equipment operational before plant on line, Maintenance only done when plant off line, Shutdown – product out of plant prior to
Ammonium nitrate fume and microprill
Prill Tower - Start Up, Normal operation, upset conditions
No. 1 ANS Plant - Start up and operation,
Emissions from the prill tower as per normal operation
Start-up – Steam vented to atmosphere until ANSSER Plant brought into Operation. ANSSER timer 10 minutes started after the ANS plant
Up Plan
Plant shutdown until equipment repaired
Not applicable – normal operation
Nil
Plant shutdown until equipment repaired
Ammonium nitrate fume and microprill
Not applicable – normal operation
Steam and Ammonia
Not applicable
shutdown, Upset conditions no effect on emissions
No. 4 Ammonium Nitrate –
Briefly Outline Back
Start-up timer (30 minutes) has timed out No. 1 ANS Plant - Upset Conditions – plant off line No. 1 ANS Plant - offline, Shutdown, Maintenance
No. 2 ANS Plant - Start up and operation,
Potential plant trips
Steam and Ammonia
Not applicable
No emissions
No applicable
Not applicable
Start-up – Steam vented to atmosphere until ANSSER Plant brought into operation. ANSSER timer 15 minutes started after the ANS plant start-
Steam and Ammonia
Not applicable
up timer (30 minutes) has timed out No. 2 ANS Plant - Upset Conditions – plant off line No. 2 ANS Plant - offline,
Potentially plant trips No emissions
Steam and Ammonia No applicable
Not applicable Not applicable
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Unit Process
Description of Occurrence of Potential Releases
Pollutants and Associated Amount of Emissions
Briefly Outline Back Up Plan
Shutdown, Maintenance Start Up – Bag house bypassed until the boiler Flyash Boiler – Start up
has reached operating temperature so as to prevent condensation on the bags in the bag house
High levels of Flyash Dust
Not Applicable
8 Compartments available. For maintenance one Flyash Boiler Maintenance
Maintenance on a bag house cell
No change
compartment is isolated and opened for repair. The flue gases pass through other 7 compartments
No. 2 Power Station – Shutdown, Upset Operation PETN Nitration Fume off
No emissions
No emissions
Not applicable
Fume off resulting from a runaway nitration reaction
NOx Fumes
Shut down the plant
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4.2
Fugitive Emissions
Over and above point source process emissions, the AEL Mining Services Modderfontein operations also results in fugitive emissions from ash dumps and burning grounds. Emission sources and emission rates from fugitive sources are described in Table 4-5 and Table 4-6 respectively. The basis for the calculation of fugitive emission rates are given in Table 4-7. Table 4-5: Fugitive emission source parameters Unique
Latitude
Longitude
(decimal degrees) of SW corner
(decimal degrees) of SW corner
Height of
Length
Width
Angle of
Release Above Ground (m)
of Area (m)
of Area (m)
Rotation from True North (°)
Source Name
Source Description
Ashdumps
Ash dump 2, 3 and coarse ash
Dump for slurried fly ash from the Fly ash boiler and coarse ash from the No.2 Boiler.
-26.0932
28.1790
Depends on dump height
433
261
23
IC100BG
IC 100 burning ground
Open burning ground for the destruction of explosive waste and explosive contaminated waste
-26.0817
28.1641
0
74
26
31
PEBG A
Packaged Explosive burning ground A
Open burning ground for the destruction of explosive waste and explosive contaminated waste
-26.0812
28.1545
0
74
26
41
PEBG B
Packaged Explosive burning ground B
Open burning ground for the destruction of explosive waste and explosive contaminated waste
-26.0825
28.1545
0
27
76
25
CordtexBG
Cordtex burning ground
-26.0809
28.1728
0
14
27
14
PentoliteBG
Pentolite burning ground
-26.0773
28.1652
0
6
7
60
Area Source ID
Open burning ground for the destruction of detonation cord, PETN, felt mats, saverall waste, cartons, plastic bags Open burning ground for the destruction of pentolite, PETN, TNT, DNT, cartons, plastic bags, charcoal
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Table 4-6: Fugitive emission rates Maximum Release
Average Annual
Wind
ID
Pollutant Name
Rate (quantity per period)
Release Rate (quantity per period)
Emission Hours
Type of Emission (Continuous / Intermittent)
Ashdumps
Particulates
0.01
0.32
24 Hours
Intermittent
Yes
Particulates
9.26
34.8
SO2
0.2
0.8
10h00 to 14h00
Routine but intermittent
No
NOx
1.61
6
Particulates
6.8
35.8
SO2
0.15
0.8
09h00 and 13h00
Routine but intermittent
No
NOx
1.18
6.2
Particulates
6.8
35.8
SO2
0.15
0.8
09h00 and 13h00
Routine but intermittent
No
NOx
1.18
6.2
Particulates
0.19
2.5
NH3
0.01
0.1
07h00 to 17h00
Routine but intermittent
No
Particulates
0.32
1.8
NH3
0.05
0.3
07h00 to 17h00
Routine but intermittent
No
IC100BG
PEBG A
PEBG B
CordtexBG
PentoliteBG
Dependent(Yes / No)
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Table 4-7: Basis of calculation for fugitive emission rates Source ID Ashdumps
Basis of Emissions Rate Calculated using the US-EPA AP42 Section 12.2.4 (Aggregate Handling and Storage Piles) empirical emissions factor equation for materials handling, using a moisture content of 0.1% and a wind speed of 1.05 m/s (obtained from meteorological data).
IC100BG
Calculated using the US-EPA AP 42 Section 13.3 (Explosives Detonation) emissions factor for ANFO detonation. Pollutants not described in AP42 Section 13.3 were estimated using US-EPA AP 42 Section 2.5 (Open Burning) emissions factor for General Refuse burning.
PEBG A
Calculated using the US-EPA AP 42 Section 13.3 (Explosives Detonation) emissions factor for ANFO detonation. Pollutants not described in AP42 Section 13.3 were estimated using US-EPA AP 42 Section 2.5 (Open Burning) emissions factor for General Refuse burning.
PEBG B
Calculated using the US-EPA AP 42 Section 13.3 (Explosives Detonation) emissions factor for ANFO detonation. Pollutants not described in AP42 Section 13.3 were estimated using US-EPA AP 42 Section 2.5 (Open Burning) emissions factor for General Refuse burning.
CordtexBG
Calculated using the US-EPA AP 42 Section 13.3 (Explosives Detonation) emissions factor for PETN detonation.
PentoliteBG
Calculated using the US-EPA AP 42 Section 13.3 (Explosives Detonation) emissions factor for TNT and PETN detonation.
4.3
Emergency Incidents
No emergency incidents were reported at the AEL Mining Services Modderfontein operations over the last two years.
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IMPACT OF ENTERPRISE ON THE RECEIVING ENVIRONMENT
5 5.1
Ambient Air Quality Impact Assessment Criteria
Prior to assessing the impact of operations at AEL Mining Services Modderfontein on human health and the environment, reference needs to be made to the environmental regulations governing the impact of such operations i.e. ambient air quality standards and guidelines. Air quality guidelines and standards are fundamental to effective air quality management, providing the link between the source of atmospheric emissions and the user of that air at the downstream receptor site. Ambient air quality standards and guideline values indicate safe daily exposure levels for the majority of the population, including the very young and the elderly, throughout an individual’s lifetime. Air quality guidelines and standards are normally given for specific averaging or exposure periods. This section summarises national and international legislation pertaining to air quality for pollutants relevant to the current study. 5.1.1 Listed Activities and Minimum Emission Standards AEL Mining Services has to comply with the existing plant Minimum Emission Standards (MES) for the listed activities as described in Section 2.1. The plant will however have to comply with new plant emission limits from 2020 onwards. The minimum emission limits for the production of acids (Table 5-1), production of chemical fertilizer (Table 5-2) and burning grounds (Table 5-3) are given below. Table 5-1: Listed activity – Subcategory 7.2 – Production of Acids Subcategory 7.2 – Production of Acids Description:
The production, bulk hand and oruse of nitric acid in concentrations exceeding 10%
Application:
All installations producing, handling or using more than 100 tons per annum of nitric acid
Substance or Mixture of Substances Common Name
Chemical Symbol
Oxides of nitrogen expressed as NO2
NOx
Sulphur dioxide
SO2
Limit value (dry mg/Nm³ under Plant Status
normal conditions of 273 Kelvin and 101.3 kPa)
New
350
Existing
2000
New
350
Existing
2800
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Table 5-2: Listed activity – Subcategory 7.3 – Production of Chemical Fertilizer Subcategory 7.3 – Production of Chemical Fertilizer Description:
The production of ammonium nitrate
Application:
All installations producing or processing more than 10 tons per month.
Substance or Mixture of Substances Common Name
Chemical Symbol
Particulate matter
PM
Total fluoride measured as hydrogen fluoride
HF
Ammonia
NH3
Limit value (dry mg/Nm³ under Plant Status
normal conditions of 273 Kelvin and 101.3 kPa)
New
50
Existing
100
New
5
Existing
30
New
50
Existing
100
Table 5-3: Listed activity – Subcategory 8.3 – Burning Grounds Subcategory 8.3 – Burning Grounds Description:
Facilities where waste material from the manufacture of explosives and contaminated explosive packaging material are destroyed.
Application:
All installations disposing of more the 100kg of material per week.
Substance or Mixture of Substances Common Name
Chemical Symbol
Dust fall
N/A
Sulphur dioxide
SO2
Limit value (dry mg/Nm³ under Plant Status
normal conditions of 273 Kelvin and 101.3 kPa)
New
a
Existing
a
New
b
Existing
b
a)
Three months running average not to exceed limit value for adjacent land use according to dust control regulations
b)
promulgated in terms of section 32 of the NEM: AQA, 2004 (Act No.39 of 2004) in eight principal wind directions. Twelve months running average not to exceed limit value as per GN 1210 of 24 December 2009. Passive diffusive measurements approved by the licensing authority carried out monthly.
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5.1.2 Controlled Emitters and Emission Standards The two boilers at the AEL Mining Services Modderfontein operations, both with a heat input of less than 50 MW, are considered controlled emitters, and should comply with the minimum emission standards described in Table 5-4. Table 5-4: Controlled emitter – Solid fuel-fired small boiler Controlled Emitter – Solid fuel-fired small boiler Description:
Small boilers fuelled with sold fuels
Application:
All small boilers fuelled with hydrocarbon based solid fuel, excluding biomass.
Substance or Mixture of Substances Common Name
Chemical Symbol
Particulate Matter
N/A
Sulphur dioxide
SO2
Limit value (dry mg/Nm³ under Plant Status
normal conditions of 10% O2, 273 Kelvin and 101.3 kPa)
New
120
Existing
250
New
2800
Existing
2800
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5.1.3 National Ambient Air Quality Standards for Criteria Pollutants Criteria pollutants are considered those pollutants most commonly found in the atmosphere, that have proven detrimental health effects when inhaled and are regulated by ambient air quality criteria. South African National Ambient Air Quality Standards (NAAQS) for PM10, NO2 and SO2 were published on the 13th of March 2009. These standards are listed in Table 5-5. Table 5-5: National Ambient Air Quality Standards for criteria pollutants Pollutant
PM10
PM2.5
NO2
SO2
Averaging Period
Limit Value (µg/m³)
Frequency of Exceedance
24 hour
75
4
1 year
40
0
24 hour (Immediate to December 2015)
65
4
1 year (Immediate to December 2015)
25
0
24 hour (2016 – 2029)
40
4
1 year (2016 – 2029)
20
0
1 hour
200
88
1 year
40
0
10 minutes
500
526
1 hour
350
88
24 hour
125
4
1 year
50
0
5.1.4 Screening Criteria for NH3 Air quality criteria for non-criteria pollutants such as NH3 are published by various sources. Criteria referred to in this study include:
Integrated Risk Information System (IRIS) chronic inhalation reference concentrations (RfCs) (US EPA, 2014), Provisional Peer Reviewed Toxicity Values (PPRTV) and cancer URFs published by the US EPA (US EPA, 2014); and
Minimal risk levels (MRLs) issued by the US Federal Agency for Toxic Substances and Disease Registry (ATSDR) (ATSDR, 2014).
The most stringent international NH3 concentration guidelines for each averaging period are given in Table 5-6.
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Table 5-6: International guidelines for ammonia Pollutant
NH3
Averaging Period
Limit Value (µg/m³)
Source
Acute (1 hour)
1180
ATSDR
Sub-chronic (1 day)
100
PPRTV
Chronic (1 year)
100
IRIS
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5.2
Atmospheric Dispersion Potential
Meteorological mechanisms govern the dispersion, transformation, and eventual removal of pollutants from the atmosphere. The analysis of hourly average meteorological data is necessary to facilitate a comprehensive understanding of the dispersion potential of the site. For the purpose of the current study use was made of meteorological data from AEL Mining Services weather station located southeast of the Modderfontein operations (at the same location as the ambient monitoring station, as shown in Figure 1-1). 5.2.1 Local wind field The horizontal dispersion of pollution is largely a function of the wind field. The wind speed determines both the distance of downwind transport and the rate of dilution of pollutants. The generation of mechanical turbulence is similarly a function of the wind speed, in combination with the surface roughness. Period, diurnal and seasonal wind roses drawn from on-site meteorological data for the period January 2010 to October 2014 are shown in Figure 5-2 and Figure 5-3. Wind roses comprise 16 spokes, which represent the directions from which winds blew during a specific period. The colours used in the wind roses below, reflect the different categories of wind speeds; the light green area, for example, representing wind speeds between 3 and 4 m/s. The dotted circles provide information regarding the frequency of occurrence of wind speed and direction categories. The frequency with which calms occurred, i.e. periods during which the wind speed was below 1 m/s are also indicated. During the reporting period, the wind field was dominated by winds from the north-westerly sector with an average wind speed of 1 m/s. Wind speeds of less than 1 m/s occurred 48% of the time, while wind speeds of more than 5.4 m/s occurred 6.2% of the time, the maximum recorded wind speed was 8 m/s. During the day the wind was predominantly from the west north-west. During the night, winds were mostly from the north. Seasonal variations in the wind field are shown in Figure 5-2. Generally the wind direction is similar across all the seasons, with higher wind speeds and less calms recorded during the spring months.
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Figure 5-1: Period average and diurnal wind roses (On-site data, 2010 - 2014)
Figure 5-2: Seasonal wind roses (On-site data, 2010 - 2014)
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5.2.2 Ambient Temperature Air temperature is important for determining the development of the mixing and inversion layers. The diurnal temperature profile for the AEL Mining Services Modderfontein monitoring station (2010 to 2014) is shown in Figure 5-3. Period average, maximum and minimum temperatures were 15°C, 39.9°C and -3.3°C respectively. The month with the highest average temperature was February (18.8°C) whilst the coldest month was July (9.1°C).
Figure 5-3: Diurnal temperature profile (On-site data, 2010 - 2012)
5.2.3
Precipitation
Precipitation is important to air pollution studies since it represents an effective removal mechanism for atmospheric pollutants and inhibits dust generation potentials. Reference is made of the precipitation trends observed at the ORTIA weather station, situated at OR Tambo International Airport (8 km south east of the Modderfontein operations). The long-term rainfall for the ORTIA station is given in Table 5-7 (Schulze, 1986). Average total annual rainfall is in the range of 718 mm. The study area falls within a summer rainfall region, with over 80% of the annual rainfall occurring during the October to March period.
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Table 5-7: Long-Term Average Monthly Rainfall for the Period 1951 – 1984 (Schulze, 1986).
Max 24 hr Rainfall (mm) Ave rainfall (mm) Ave no. of rain days
5.3
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Total
188
55
92
49
70
31
30
25
42
89
65
102
-
131
95
81
55
19
7
6
6
26
72
114
106
718
14.4
11.0
11.0
8.5
3.6
2.0
1.2
2.0
3.5
9.6
14.3
14.0
95.5
Air Quality Monitoring Data
The AEL Mining Services Modderfontein monitoring station also records 5-minute average concentrations of NO2, NO, NOx, SO2, PM10, PM2.5 and PM1. NH3 concentrations were measured in the past, but due to concentrations being below the detection level, NH3 monitoring was discontinued. Ambient monitored air quality data at the monitoring station is available for the period January 2010 to October 2014. During the period 2010 to 2014 (Table 5-8) no exceedances of the SA NAAQS (for the criteria pollutants of concern, namely: NO x, SO2, PM10 and PM2.5) were recorded. Table 5-8: Summary of air quality monitoring data at the AEL Mining Services Modderfontein monitoring station (2010 – 2014) Pollutant
NOx
SO2
PM10
PM2.5
2010
0.02
0.36
35.2
21.5
2011
0.03
0.12
28.3
17.6
2012
0.02
0.01
17.0
11.3
2013
0.05
0.01
21.4
12.2
2014
0.02
0.02
12.2
9.3
Highest Daily Concentration
6.1
335.0
162.1
101.8
1
1
3
Annual Average
Exceedances of Daily NAAQS (4 allowed) Highest Hourly Concentration
72.2
462.0
640.9
451.5
Exceedances of Hourly NAAQS (88 allowed)
0
2
N.A.
N.A.
An analysis of the observed NOx, SO2, PM10 and PM2.5 concentrations at the monitoring station was completed, in which the concentration values have been categorised into wind speed and direction bins for different concentrations. This information is most easily visualised as polar plots (Carslaw & Ropkins, 2012). The polar plots provide an indication of the directional contribution as well as the dependence of concentrations on wind Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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speed. Diurnal concentration plots were also created; this can be used to identify possible sources in the area based on the times of highest concentrations. The highest NOx concentrations were recorded at low wind speeds (Figure 5-4) from all directions, with slightly higher concentrations recorded when the wind was from the east. The highest NOx concentrations were recorded during the morning and evening peak hours (Figure 5-5), characteristic of vehicle emissions associated with traffic peaks. The highest SO2 concentrations were recorded at low and medium wind speeds (Figure 5-6) from the northwest, southeast and south. The highest SO2 concentrations were recorded in the mid-morning (Figure 5-7), characteristic of industrial emissions. Likely sources of SO 2 include the industrial areas of Founders Hill (northwest), Sebenza (south) and Spartan (southeast). Other industries expected to contribute to ambient SO 2 concentrations are the Modderfontein Industrial Complex (northwest) and Kelvin Power Station (southeast). High PM10 concentrations were recorded from all wind directions (Figure 5-8), especially under incidences of high wind speeds. The highest PM10 concentrations were recorded during the late afternoon and early evening (Figure 5-9). The source types contributing to these concentrations are likely a combination from a variety of source groups such as vehicle tailpipe emissions (slight increase during morning traffic hours), industrial sources (lower concentrations over weekends), Kelvin Power Station, wind erosion, domestic fuel burning and veld fires. Wind speeds of higher than 5.4 m/s, when wind erosion is likely to occur, were measured 6.2% of the time. Recorded PM2.5 concentrations showed similar trends to that of PM10 – from all wind directions at all wind speeds but at lower concentrations (Figure 5-10). Similar to PM10, the highest PM2.5 concentrations were recorded during the late afternoon and early evening (Figure 5-11). The sources contributing to PM2.5 concentrations are likely the same as those contributing to PM10 concentrations.
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Figure 5-4: NOx polar plot for the AEL Mining Services Modderfontein monitoring station
Figure 5-5: Diurnal NOx profile for the AEL Mining Services Modderfontein monitoring station Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Figure 5-6: SO2 polar plot for the AEL Mining Services Modderfontein monitoring station
Figure 5-7: Diurnal SO2 profile for the AEL Mining Services Modderfontein monitoring station Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Figure 5-8: PM10 polar plot for the AEL Mining Services Modderfontein monitoring station
Figure 5-9: Diurnal PM10 profile for the AEL Mining Services Modderfontein monitoring station Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Figure 5-10: PM2.5 polar plot for the AEL Mining Services Modderfontein monitoring station
Figure 5-11: Diurnal PM2.5 profile for the AEL Mining Services Modderfontein monitoring station Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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5.4
Atmospheric Dispersion Modelling Methodology
Prior to interpreting atmospheric dispersion modelling results the reader should take note of the methodology adopted in the simulation of ambient pollutant concentrations and dustfall rates. Dispersion models compute ambient pollutant concentrations and dustfall rates as a function of source configurations, emission strengths and meteorological characteristics, thus providing a useful tool to ascertain the spatial and temporal patterns in the ground level concentrations arising from the emissions of various sources. Increasing reliance has been placed on concentration estimates from models as the primary basis for environmental and health impact assessments, risk assessments and emission control requirements. It is therefore important to carefully select a dispersion model for the purpose.
5.4.1.1 Dispersion Model Selection Three levels of assessment are defined in the South African Regulations for Air Dispersion Modelling:
Level 1: where worst-case air quality impacts are assessed using simpler screening models;
Level 2: for assessment of air quality impacts as part of license application or amendment processes, where impacts are the greatest within a few kilometres downwind (less than 50 km);
Level 3: requires more sophisticated dispersion models (and corresponding input data, resources and model operator expertise) in situations: o
Where a detailed understanding of air quality impacts, in time and space, is required;
o
Where it is important to account for causality effects, calms, non-linear plume trajectories, spatial variations in turbulent mixing, multiple source types, and chemical transformations;
o
When conducting permitting and/or environmental assessment process for large industrial developments that have considerable social, economic and environmental consequences;
o
When evaluating air quality management approaches involving multi-source, multi-sector contributions from permitted and non-permitted sources in an airshed; or,
o
When assessing contaminants resulting from non-linear processes (e.g. deposition, groundlevel ozone (O3), particulate formation, visibility).
This study was considered to meet the requirements of a Level 2 assessment, and the US-EPA AERMOD model was selected on the basis that this Gaussian plume model is well suited to simulate dispersion where transport distances are likely to be less than 50 km. As mentioned, Gaussian plume models are best used for near-field applications where the steady-state meteorology assumption is most likely to apply. AERMOD is a model developed with the support of the AMS/EPA Regulatory Model Improvement Committee (AERMIC), whose objective has been to include state-of the-art science in regulatory models (Hanna, Egan, Purdum, & Wagler, 1999). AERMOD is a dispersion
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modelling system with three components, namely: AERMOD (AERMIC Dispersion Model), AERMAP (AERMOD terrain pre-processor), and AERMET (AERMOD meteorological pre-processor). AERMOD is an advanced new-generation model. It is designed to simulate pollution concentrations from continuous point, flare, area, line, and volume sources. AERMOD offers new and potentially improved algorithms for plume rise and buoyancy, and the computation of vertical profiles of wind, turbulence and temperature however it retains the single straight line trajectory limitation. AERMET is a meteorological pre-processor for AERMOD. Input data includes hourly cloud cover observations, surface meteorological observations and upper air soundings. Output includes surface meteorological observations and parameters and vertical profiles of several atmospheric parameters. AERMAP is a terrain pre-processor designed to simplify and standardise the input of terrain data for AERMOD. Input data includes receptor terrain elevation data. The terrain data may be in the form of digital terrain data. The output includes, for each receptor, location and height scale, which are elevations used for the computation of air flow around hills. A disadvantage of the model is that spatial varying wind fields, due to topography or other factors cannot be included. Input data types required for the AERMOD model include: source data, meteorological data (preprocessed by the AERMET model), terrain data and information on the nature of the receptor grid. Version (version 7.2.5) of the AERMOD and its pre-processors were used in the study.
5.4.1.2 Meteorological Requirements For the purpose of the current study use was made of meteorological data from the AEL Mining Services weather station (located at the same location as the ambient monitoring station, as shown in Figure 1-1) southeast of the Modderfontein operations. Meteorological data for the period 2010 to 2014 was used in this assessment. Data availability is shown in Table 5-9. The meteorological data set is in compliance with the South African Regulations for Air Dispersion Modelling, which states that: “A minimum of 1-year on-site specific data or at least three years of appropriate off-site data must be used for Level 2 assessments”. Table 5-9: Meteorological Data Availability Total = 85%
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
2010
100%
100%
92%
100%
100%
100%
100%
100%
100%
100%
100%
100%
2011
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
2012
100%
100%
100%
100%
100%
0%
0%
0%
0%
0%
0%
0%
2013
0%
100%
100%
100%
100%
100%
100%
100%
100%
100%
0%
0%
2014
0%
100%
100%
100%
100%
100%
100%
100%
100%
97%
0%
0%
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5.4.1.3 Source Data Requirements The AERMOD model is able to model point, jet, area, line and volume sources. Sources at the AEL Mining Services Modderfontein operations were modelled as follows:
Stacks – modelled as point sources;
Prilling towers – modelled as capped point sources;
Burning grounds – modelled as area sources; and,
Ash dumps – modelled as area sources.
5.4.1.4 Modelling Domain The dispersion of pollutants expected to arise from AEL Mining Services Modderfontein operations was modelled over an area covering 10 km (east-west) by 10 km (north-south). The area was divided into a grid matrix with a resolution of 100 m, with the facility located centrally. AERMOD calculates ground-level (1.5 m above ground level) concentrations at each grid receptor point.
5.4.1.5 Presentation of Results Atmospheric dispersion modelling was undertaken to determine highest hourly, highest daily and annual average ground level concentrations for each of the pollutants considered in the study. Averaging periods were selected to facilitate the comparison of predicted pollutant concentrations to relevant NAAQS and inhalation health screening criteria. In addition to dispersion modelling for current emissions rates, a second scenario was modelled to assess the impact of all sources if they were to comply with the Section 21: Minimum Emission Standards (MES). All sources of SO2 are already in compliance with the MES, and this scenario was only applicable to NOx, PM10 and NH3 sources. Ground-level concentration isopleths plots presented in this section depict interpolated values from the concentrations simulated by AERMOD for each of the receptor grid points specified. Ambient air quality criteria apply to areas where the Occupational Health and Safety regulations do not apply, thus outside the property or lease area. Ambient air quality criteria are therefore not occupational health indicators but applicable to areas where the general public has access i.e. off-site.
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5.4.1.6 Atmospheric Dispersion Modelling Assumptions and Limitations The following important assumptions and limitations to atmospheric dispersion modelling should be noted:
Nitrogen monoxide (NO) is rapidly converted in the atmosphere into the much more toxic NO 2. The rate of this conversion process is determined by the rate of the physical processes of dispersion and mixing of the plume and the chemical reaction rates as well as the local atmospheric ozone concentration. For the purpose of this assessment all NOx was assumed to be emitted as NO2.
Routine emissions from the AEL Mining Services Modderfontein operations were simulated. Atmospheric releases occurring as a result of non-routine conditions were not included in the dispersion modelling except for the ammonium nitrate solution plants (ANS1 and ANS2). Here the ANSSER plant was taken as the routine source of emissions with ANS1 and ANS2 simulated as upset conditions – during start-up the ANS plant emissions are vented to atmosphere prior to being routed into the ANSSER plant.
Simulation results represent ambient pollutant concentrations as a result of AEL Mining Services Modderfontein operations emissions only.
There will always be some error in any geophysical model, but it is desirable to structure the model in such a way to minimise the total error. A model represents the most likely outcome of an ensemble of experimental results. The total uncertainty can be thought of as the sum of three components: the uncertainty due to errors in the model physics; the uncertainty due to data errors; and the uncertainty due to stochastic processes (turbulence) in the atmosphere. Nevertheless, dispersion modelling is generally accepted as a necessary and valuable tool in air quality management.
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5.5
Dispersion Modelling Results
5.5.1 NOx emissions Two scenarios were included in the NOx emission dispersion modelling, one with the current emissions as reported in Table 4-2, and a second scenario assuming all sources were to comply with the 2020 MES. A list of the NOx emission sources that exceed the MES is provided in Table 5-10. Even though the PETN boiling tube stack markedly exceeds the MES, due to its low flow rate, this stack is the least significant source of NOx at the AEL Mining Services Modderfontein operations, emitting only 0.027 g/s of NOx, approximately 0.13% of the total NOx emitted from all point sources. Table 5-10: NOx emission sources that are in exceedance of the MES. Unit Process
Current Emissions (mg/Nm³)
2015 MES Limit (mg/Nm³)
2020 MES Limit (mg/Nm³)
No. 9 Nitric Acid stack
360
2 000
350
Stills stack
3 396
2 000
350
PETN boiling tube stack
2 003 000
2 000
350
Isopleth plots are provided for highest hourly (Figure 5-12 and Figure 5-13) and annual average (Figure 5-14 and Figure 5-15) ground-level NOx concentrations, together with a summary (Table 5-11) of simulated NOx concentrations at all sensitive receptor locations. Simulated annual average and highest hourly NO x concentrations due to current (MES non-compliant) AEL Mining Services Modderfontein operations are in compliance with the SA NAAQS for all locations outside the property boundary. Compliance with the MES will lead to a slight reduction in already low NOx ground level concentrations at sensitive receptor locations.
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Table 5-11: Simulated NOx concentrations at sensitive receptor locations. Scenario
Current Emissions
Averaging Period
2020 MES
Percentage Reduction in Impact
Annual
Highest
Annual
Highest
Average (µg/m³)
Hourly (µg/m³)
Average (µg/m³)
Hourly (µg/m³)
(NAAQS = 40 µg/m³)
(NAAQS = 200 µg/m)
(NAAQS = 40 µg/m³)
(NAAQS = 200 µg/m³)
Annual Average %
Highest Hourly %
Linbro Park
0.4
14.4
0.3
13.4
28%
7%
Thornhill
0.7
25.3
0.4
23.8
44%
6%
Greenstone
0.4
16.9
0.2
16.2
46%
4%
Illiondale
0.9
20.5
0.6
19.6
29%
4%
Monitoring Station
0.8
29.5
0.6
26.7
23%
9%
Esther Park
1.1
38.5
0.8
33.6
20%
13%
Edleen
0.5
20.1
0.4
18.9
24%
6%
Terenure
0.8
27.3
0.6
26.1
22%
5%
Birch Acres
0.2
14.2
0.1
13.6
25%
4%
Chloorkop
0.2
14.2
0.2
14.0
22%
1%
Klipfontein View
0.2
15.1
0.1
14.9
19%
1%
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Figure 5-12: Simulated highest hourly NOx concentration due to current AEL Mining Services Modderfontein operations.
Figure 5-13: Simulated highest hourly NOx concentration due to AEL Mining Services Modderfontein operations in compliance with 2020 MES.
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Figure 5-14: Simulated annual average NOx concentration due to current AEL Mining Services Modderfontein operations.
Figure 5-15: Simulated annual average NOx concentration due to AEL Mining Services Modderfontein operations in compliance with 2020 MES.
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5.5.2 SO2 emissions All SO2 emission sources at the AEL Mining Services Modderfontein operations comply with the Section 21: MES, therefore only a current emissions scenario was simulated. Isopleth plots are provided for highest hourly (Figure 5-16), highest daily (Figure 5-17) and annual average (Figure 5-18) ground-level SO2 concentrations, together with a summary (Table 5-12) of simulated SO2 concentrations at all sensitive receptor locations. Simulated annual average, highest daily and highest hourly SO2 concentrations due to current AEL Mining Services Modderfontein operations are in compliance with the SA NAAQS for all locations within the study area. Table 5-12: Simulated SO2 concentrations at sensitive receptor locations. Scenario
Current AEL Emissions Highest Daily (µg/m³)
Highest Hourly (µg/m³)
(NAAQS = 50 µg/m³)
(NAAQS = 125 µg/m³, 4 exceedances allowed)
(NAAQS = 350 µg/m³, 88 exceedances allowed)
Linbro Park
0.2
3.3
14.0
Thornhill
0.3
4.2
25.5
Greenstone
0.1
2.2
19.9
Illiondale
0.4
4.5
22.0
Monitoring Station
0.5
4.7
28.7
Esther Park
0.7
5.6
36.3
Edleen
0.3
5.6
25.3
Terenure
0.4
7.9
40.8
Birch Acres
0.1
2.1
15.5
Chloorkop
0.1
2.5
15.0
Klipfontein View
0.1
2.0
14.6
Averaging Period
Annual Average (µg/m³)
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Figure 5-16: Simulated highest hourly SO2 concentration due to AEL Mining Services Modderfontein operations.
Figure 5-17: Simulated highest daily SO2 concentration due to AEL Mining Services Modderfontein operations.
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Figure 5-18: Simulated annual average SO2 concentration due to AEL Mining Services Modderfontein operations. 5.5.3 PM10 emissions Two scenarios were included in the PM10 emission dispersion modelling, one with the current emissions as reported in Table 4-2, and a second scenario if all sources were to comply with the 2020 MES. A list of the PM10 emission sources that exceed the 2015 MES is provided in Table 5-13. Table 5-13: PM10 emission sources that are in exceedance of the 2015 MES. Unit Process
Current Emissions (mg/Nm³)
2015 MES Limit (mg/Nm³)
No. 3 Ammonium Nitrate Evaporator
1 026
100
No. 2 Boiler (a)
922
250(b)
Notes: (a)The No. 2 Boiler is only used as a backup when the Flyash Boiler is not running; the amount of time that the No. 2 Boiler is online varies substantially. During 2014 the No 2 Boiler was operational for 3 269 hours (38% of the year), while in 2013 the No. 2 Boiler was only operational for 974 hours (11% of the year). (b) The No. 2 boiler is not a listed activity but a controlled emitter and has to comply with the emission standards as described in Table 5-4.
Isopleth plots are provided for highest daily (Figure 5-19 and Figure 5-20) and annual average (Figure 5-21 and Figure 5-22) ground-level PM10 concentrations, together with a summary (Table 5-14) of simulated PM10 concentrations at all sensitive receptor locations. Simulated annual average and highest daily PM10 concentrations due to current (MES non-compliant) AEL Mining Services Modderfontein operations are in compliance with the SA NAAQS for all locations outside the property boundary. For the MES compliant Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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emissions scenario, simulated ground level concentrations at the various sensitive receptors remains to be within compliance with the SA NAAQS and reduce between 9% and 42%. Simulated PM10 concentrations only exceed the SA NAAQS up to 300 m from the burning grounds. Table 5-14: Simulated PM10 concentrations at sensitive receptor locations. Scenario
Current Emissions
Percentage Reduction in Impact
2020 MES
Annual
Highest
Annual
Highest
Average (µg/m³)
Daily (µg/m³)
Average (µg/m³)
Daily (µg/m³)
(NAAQS =
(NAAQS =
(NAAQS = 40
(NAAQS =
40 µg/m³)
75 µg/m³)
µg/m³)
75 µg/m³)
Linbro Park
0.6
4.8
0.4
Thornhill
0.8
5.3
Greenstone
0.5
Illiondale
Annual
Highest
Average %
Daily %
3.4
33%
28%
0.5
3.6
34%
33%
3.9
0.4
3.3
30%
16%
1.3
9.9
0.9
9.1
34%
8%
Monitoring Station
1.8
14.4
1.2
13.1
35%
9%
Esther Park
1.9
11.0
1.1
8.0
42%
28%
Edleen
1.4
12.3
1.0
11.5
28%
6%
Terenure
2.4
17.8
1.8
16.2
25%
9%
Birch Acres
0.3
3.3
0.2
2.1
35%
37%
Chloorkop
0.3
3.3
0.2
2.7
38%
19%
Klipfontein View
0.3
2.6
0.2
1.9
37%
29%
Averaging Period
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Figure 5-19: Simulated highest daily PM10 concentration due to current AEL Mining Services Modderfontein operations.
Figure 5-20: Simulated highest daily PM10 concentration due to AEL Mining Services Modderfontein operations in compliance with 2020 MES.
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Figure 5-21: Simulated annual average PM10 concentration due to current AEL Mining Services Modderfontein operations.
Figure 5-22: Simulated annual average PM10 concentration due to AEL Mining Services Modderfontein operations in compliance with 202 MES.
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5.5.4 NH3 emissions As for PM10; two scenarios were modelled for NH3 emission: current emissions as reported in Table 4-2 and a second scenario if all sources were to comply with the 2020 MES. A list of the NH3 emission sources that exceed the MES is provided in Table 5-15. Table 5-15: NH3 emission sources that are in exceedance of the 2015 MES. Online Time
Unit Process
Current Emissions (mg/Nm³)
2015 MES Limit (mg/Nm³)
(Percentage)
ANPP3EVAP
456
100
100
ANS1
10 180
100
5.7(a)
ANS2
2 430
100
4.1(a)
ANSSER
779
100
94.3
Notes: (a) During start up the ANS plant emissions are vented to atmosphere prior to being routed into the ANSSER (Ammonium Nitrate Solution Stack Emission Reduction) plant. Percentages given here are the amount of time, in 2014, that emissions were vented through the ANS1 and ANS2 stacks without being routed to the ANSSER plant.
Isopleth plots are provided for highest hourly (Figure 5-23 and Figure 5-24), highest daily (Figure 5-25 and Figure 5-26) and annual average (Figure 5-27 and Figure 5-28) ground-level NH3 concentrations, together with a summary (Table 5-14) of simulated NH3 concentrations at all sensitive receptor locations. Simulated annual average, highest daily and highest hourly NH3 concentrations due to current AEL Mining Services Modderfontein operations are below the EPA IRIS Chronic RfC, the EPA Sub-chronic PPRTV and the ATSDR Acute MRL respectively. Compliance with the MES will lead to a slight reduction in already low NH3 ground level concentrations at sensitive receptor locations.
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Table 5-16: Simulated NH3 concentrations at sensitive receptor locations. Scenario
Current Emissions
Percentage Reduction in Impact
2020 MES
Averaging Period
Highest Daily (µg/m³)
Annual Average (µg/m³)
Highest Daily (µg/m³)
Annual Average (µg/m³)
Highest Daily %
Annual Average %
Linbro Park
1.2
0.11
1.2
0.11
5%
3%
Thornhill
1.9
0.17
1.9
0.16
2%
6%
Greenstone
1.5
0.15
1.5
0.14
1%
4%
Illiondale
1.7
0.21
1.7
0.20
1%
2%
Monitoring Station
2.0
0.22
1.8
0.17
8%
25%
Esther Park
2.2
0.28
1.7
0.17
21%
41%
Edleen
2.2
0.16
2.1
0.15
4%
11%
Terenure
2.5
0.22
2.4
0.21
1%
5%
Birch Acres
1.0
0.05
1.0
0.04
0%
7%
Chloorkop
1.9
0.05
1.9
0.05
2%
5%
Klipfontein View
0.6
0.04
0.6
0.03
0%
6%
Figure 5-23: Simulated highest hourly NH3 concentration due to current AEL Mining Services Modderfontein operations. Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Figure 5-24: Simulated highest hourly NH3 concentration due to AEL Mining Services Modderfontein operations in compliance with the 2020 MES.
Figure 5-25: Simulated highest daily NH3 concentration due to current AEL Mining Services Modderfontein operations.
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Figure 5-26: Simulated highest daily NH3 concentration due to AEL Mining Services Modderfontein operations in compliance with the 2020 MES.
Figure 5-27: Simulated annual average NH3 concentration due to current AEL Mining Services Modderfontein operations.
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Figure 5-28: Simulated annual average NH3 concentration due to AEL Mining Services Modderfontein operations in compliance with the 2020 MES. 5.5.5 Comparison of Measured and Predicted Concentrations In this section a comparison is made between measured and simulated NOx SO2 and PM10. Reference is made to the overall highest hourly; highest daily and annual average measured and simulated concentrations (Table 5-17). Table 5-17: Comparison of Measured and Predicted Concentrations Pollutant
SO2
NOx
PM10
Averaging Period
Simulated
Measured
Simulated/Measured
Annual
0.5
0.36
138%
Daily
4.7
335
1%
Hourly
28.7
462
6%
Annual
0.8
0.05
1 600%
Hourly
29.5
6.1
480%
Annual
1.8
35.2
5%
Daily
14.4
162.1
9%
Simulated and measured SO2 and PM10 concentrations show good correlation, taking into consideration background sources of these pollutants as described in Section 5.3. Simulated annual average NOx
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concentrations were considerably higher than measured concentrations of these pollutants. Discrepancies between measured and simulated concentrations can be attributed to various factors, including:
Uncertainties in the stack monitoring results. Only isokinetic sampling results were available for most of the sources. It is likely that NOx emissions from the stacks will vary with time and that lower emission periods are not reflected in the isokinetic data. It is also possible that the operational time of the No. 2 Boiler, used as a backup, was overestimated.
Fugitive NOx emissions from the burning grounds were quantified using internationally published emissions factor data and it is possible that these emissions are overestimated.
5.5.6 Conclusion A number of sources at AEL Mining Services Modderfontein operations are in non-compliance with the 2015 MES. NOx emission sources include the Stills stack and PETN boiling tube stack. For PM10 it is the No. 3 Ammonium Nitrate Evaporator and for ammonia it is ANPP3EVAP; ANS1; ANS2 and ANSSER. Even with these sources in non-compliance with the 2015 MES, the resulting simulated ground level concentrations comply with the SA NAAQSs for NOx and PM10 at all sensitive receptor locations within the study area. The simulated NH3 concentrations were below the EPA IRIS Chronic RfC, the EPA Sub-chronic PPRTV and the ATSDR Acute MRL respectively, at all locations. All sources of SO2 emissions comply with the 2015 MES and resulted in ground level concentrations well below the SA NAAQSs. Compliance with the 2020 MES will lead to a slight reduction in already low NOx, PM10 and NH3 ground level concentrations at all sensitive receptor locations within the study area.
5.6
Analysis of Emissions’ Impact on the Environment
An assessment of air pollution impacts on soil, water and receptors other than human were not included in the investigation since it was not specifically requested by the Air Quality Officer.
6
COMPLAINTS
A complaints register is in place at the AEL Mining Services Modderfontein operations, see Annexure C for complaints received from 2012 to 2014. Most of the complaints pertained to an ammonia smell with complainants ranging between Modderfontein Industrial to the surrounding areas and residences. The ammonia odour complaints reduced from 2011 and 2012 – eight complaints – to three in 2013 and five in 2014.
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CURRENT OR PLANNED AIR QUALITY MANAGEMENT INTERVENTIONS
7 7.1
Air Quality Improvements to date
AEL Mining Services have indicated that they are committed to reducing air emissions as far as is practical and feasible for pre-existing facilities and operations. This commitment is indicated by the numerous measures that the operation has implemented in this regard as detailed below:
In 1979 packed bed scrubber units with circulating water flow were commissioned for ANS 2.
In 1985 Brink Filter Units with demister pads where installed at the ANS1&2 Plants.
In 2001 Monsanto spray panels (demister) with circulating acidified weak ammonium nitrate solution to assist in the cleaning of the generated emissions were fitted to ANS 2.
Improved maintenance on the dust scrubber units attached to the drying drums on No 3 Ammonium Nitrate plant have reduced the AN dust emissions.
During 2009 AEL Mining Services commissioned the Ammonium Nitrate Solution Stack Emission Reduction (ANSSER) plant.
In 2004 installation of the NOx column into the Stills building to replace the old NOx column.
In 2008 two Clean Development Mechanism projects were registered for the reduction of N2O emissions from the No.9 and No. 11 Nitric Acid Plants.
In addition various plants have been closed down on the Modderfontein site over the years which have resulted in further improvements to the air quality in Modderfontein. The plant closures have included No. 2 Ammonia Plant in 1985 and No.10 Nitric Acid Plant and the Limestone Ammonium Nitrate (LAN) Plant in the mid 1990’s, No. 4 ammonia Plant and Urea Plant in 2000.
7.2
Future Air Quality Management Interventions
The Sections below provide a summary of the actions proposed by AEL Mining Services to achieve compliance with the MES for both the 2015 compliance timeframes and the 2020 compliance timeframes. This is a plan and like any plan it needs to be dynamic and adaptable to information gathered as part of the planning process. As such while AEL Mining Services commits to achieving compliance with both the 2015 and 2020 compliance timeframes, the individual steps and the timing thereof may be subject to change. 7.2.1 Stills Figure 7-1 provides the road map to compliance for the AEL Mining Services Stills Plant and details proposed actions and the timing thereof. 7.2.2 PETN Plant Figure 7-2 provides the road map to compliance for the AEL Mining Services PETN Plant and details proposed actions and the timing thereof. Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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7.2.3 ANS 1 and 2 Plants and ANNSER Plant Figure 7-3 provides the road map to compliance for the AEL Mining Services ANS 1 and 2 Plants including the ANNSER Plant and details proposed actions and the timing thereof. 7.2.4 No. 3 Ammonium Nitrate Evaporator Figure 7-4 below provides the road map to compliance for the AEL Mining Services No. 3 Ammonium Nitrate Evaporator and details proposed actions and the timing thereof. 7.2.5 No. 9 Nitric Acid Plant Figure 7-5 below provides the road map to compliance for the AEL Mining Services No. 9 Nitric Acid Plant and details proposed actions and the timing thereof. 7.2.6 No. 11 Nitric Acid Plant Figure 7-6 below provides the road map to compliance for the AEL Mining Services No. 11 Nitric Acid Plant and details proposed actions and the timing thereof.
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Action
2015
2016
2017
2018
2019
2020
Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar
Stills Problem identification and investigation Design abatement system Hazop study Quotation for manufacturing, installation and EP approval EIA Fabrication of equipment Installation Commissioning and review of emissions
Figure 7-1: Roadmap to compliance for the Stills
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Action
2015
2016
2017
2018
2019
2020
Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar
PETN (R12 million) Technology investigation Design abatement system Hazop study Quotation for manufacturing, installation and EP approval EIA Fabrication of equipment Installation Commissioning and review of emissions
Figure 7-2: Roadmap to compliance for the PETN Plant
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Action
2015
2016
2017
2018
2019
2020
Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar
ANSSER Technology investigation Design abatement system Hazop study Quotation for manufacturing, installation and EP approval EIA Fabrication of equipment Installation Commissioning and review of emissions
Figure 7-3: Roadmap to compliance for ANS 1 and 2 and the ANNSER Plant
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Action
2015
2016
2017
2018
2019
2020
Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar
No.3 AN Evaporator - Ammonia & ammonium nitrate Problem identification and investigation Design abatement system Hazop study Quotation for manufacturing, installation and EP approval EIA Fabrication of equipment Installation Commissioning and review of emissions
Figure 7-4: Roadmap to compliance for No. 3 Ammonium Nitrate Plant including the evaporator
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Action
2015
2016
2017
2018
2019
2020
Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar
No. 9 Nitric Acid Identify preferred technology Design abatement system Quotation for manufacturing, installation and EP approval EIA Fabrication and delivery No. 9 Nitric Acid statutory shutdown Installation of equipment Commissioning
Figure 7-5: Roadmap to compliance for No. 9 Nitric Acid Plant
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Action
2015
2016
2017
2018
2019
2020
Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar Apr- Jun Jul - Sep Oct - Dec Jan -Mar
No. 11 Nitric Acid Identify preferred technology Design abatement system Quotation for manufacturing, installation and EP approval EIA Fabrication and delivery No. 11 Nitric Acid statutory shutdown Installation of equipment Commissioning
Figure 7-6: Roadmap to compliance for No. 11 Nitric Acid Plant
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COMPLIANCE AND ENFORCEMENT HISTORY
8
No formal notices for non-compliance have been received from the authorities. The AEL Mining Services Modderfontein operations’ compliance with the NEM: AQA is given in Table 8-1. Table 8-1: The AEL Mining Services Modderfontein operations’ compliance with the NEM: AQA. Pollutant
Minimum Emission Limits
National Ambient Air Quality Standards
PM10
One source is in exceedance of the 2015 MES (Table 5-13).
Simulated and measured PM10 ground level concentrations are in compliance with the SA NAAQS.
SO2
All sources are in compliance with the 2015 MES.
Simulated and measured SO2 ground level concentrations are in compliance with the SA NAAQS.
Two sources are in exceedance
Simulated and measured NOX ground level concentrations are in
of the 2015 MES (Table 5-10).
compliance with the SA NAAQS (for NO2).
Two sources are in exceedance of the 2015 MES (Table 5-15).
NH3 is not a criteria pollutant. Simulated NH3 ground level concentrations are below the most stringent international health guidelines for all areas except the immediate vicinity of the ANS plants.
NOx
NH3
9 9.1
ADDITIONAL INFORMATION References
ATSDR. (2014, June 24). ATSDR - Minimal Risk Levels for Hazardous Substances (MRLs): ATSDR. Retrieved from ATSDR Web site: http://www.atsdr.cdc.gov/mrls/index.asp Carslaw, D. C., & Ropkins, K. (2012). openair - an R package for air quality data analysed. Environmental Modelling & Software Volume 27-28, 52-61. Hanna, S. R., Egan, B. A., Purdum, J., & Wagler, J. (1999). Evaluation of ISC3, AERMOD, and ADMS Dispersion Models with Observations from Five Field Sites. Schulze, B. R. (1986). Climate of South Africa, Part 8. General Survey, WB 28. Pretoria: Weather Bureau, Department of Transport. US EPA. (2014, January 17). Databases and Tools|Waste and Cleanup Risk Assessment|Office of Solid Waste and Emergency Response: US EPA. Retrieved from US EPA Web site: http://hhpprtv.ornl.gov/ US EPA. (2014, December 31). Integrated Risk Information System (IRIS): US EPA. Retrieved from US EPA Web site: http://www.epa.gov/iris/
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10 ANNEXURE A
DECLARATION OF ACCURACY OF INFORMATION – APPLICANT
Name of Enterprise: Declaration of accuracy of information provided: Atmospheric Impact Report in terms of section 30 of the Act. I, [duly authorised], declare that the information provided in this atmospheric impact report is, to the best of my knowledge, in all respects factually true and correct. I am aware that the supply of false or misleading information to an air quality officer is a criminal offence in terms of section 51(1)(g) of this Act. Signed at
on this
day of
SIGNATURE
CAPACITY OF SIGNATORY
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11 ANNEXURE B
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12 ANNEXURE C – COMPLAINTS REGISTER Date/time
Action taken
Feedback
Goodwill (Heartland) reported a strong Ammonia smell at Pinelands R4 building
DEC Niemand attended and report negative ammonia test results.
Environmental group paged. OB 499/01/11
@ 13:36
Strong Ammonia smell
Tammy (Heartland) reported a strong Ammonia smell at 4 Ammonia in the Modderfontein Industrial Complex
DEC Niemand attended and could not detect an Ammonia smell. DEC also contacted Nitrates control room
Feedback given to Tammy via email and telephonically. OB 594/01/11
25/01/11
Chemical smell
Michael from 6 Gazania Road, Esther Park reported a strong chemical smell.
DEC Hattingh reported that the smell is not coming from AEL site. Oxy oil smell coming from Chloorkop site
Environmental group paged. Feedback given to complainant. OB 628/01/11
21/01/11 @ 11:41 24/01/11
Complaint /
Complainant /
Incident
Reporter
Strong Ammonia smell
@ 11:13
NW – SE, W/S 9 km/h 09/02/2011 @ 16:07
Ammonia Smell
Russell H. of Tantalite in the Modderfontein Industrial Complex complained of a strong smell of Ammonia
Nitrates control room contacted and Donald confirmed that ANS 1 plant was being started. Russell was given feedback.
OB No. 252/02/2011
04/03/2011
Explosions
Robbie Vermont, Chairman of the Modderfontein CAER committee reported a number of blasts heard in Thornhill Manor.
DEC Marius responded saying AEL had been destroying explosives and that the operation was nearly complete
Environmental group notified
20/03/2011 @ 02:55
Tear Gas Smell
Tsoaela April of Pentolite plant (AEL) reported a strong smell of Tear gas at building BP 7.
DEC Hattingh confirmed that he used Tear gas at AM Magazines to scare away intruders. W/Speed – 04km/h and W/ Direction NE/SW
Environmental group paged. OB No. 379/03/2011
21/05/2011
Ammonia smell
Nico of JN Rebuild reported the smell of ammonia at the brick yard in the Modderfontein Industrial Complex.
DEC attended, and found no 2 can pump was leaking but it was sealed shortly afterwards.
Ammonia smell
An employee from Senet, Moddercrest, complained of the smell of ammonia at High Street
No ammonia smell was detected, feedback given to the complainant
DEC Barnard J. attended.
An employee at Dets, AEL, reported the smell of ammonia. The ammonia reading was 14 ppm and
ANS 1 was investigated and monitored.
DEC J. Barnard attended.
The cause was offloading
OB 468/10/11
@ 08:20
17/08/2011 @ 09:15
21/10/2011 @ 20:40
Ammonia smell
Environmental group paged OB 387/08/2011
Environmental group notified
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Date/time
Complaint /
Complainant /
Incident
Reporter
Action taken
Feedback
at Nitrates Storage it was 33 ppm. ANS 1 was investigated. Wind direction – North – South; Wind speed – Between 7km/h – 14 km/h and Wind Rose – 20 degrees.
of ammonia at Storage and Distribution.
The smell of ammonia was reported at DETS.
DEC Niemand attended and there was no ammonia smell detected
DEC Niemand attended
24/10/2011 @ 08:25
Ammonia smell
27/10/2011
Ammonia smell
A tenant in the Modderfontein Industrial Complex reported the smell of ammonia near LP5 ammonia storage tank
DEC Niemand attended, but there was no ammonia
DEC Niemand attended. Environmental group paged
03/02/2012
Ammonia smell
Thabang, a worker at Dets, AEL reported a strong smell of ammonia. Wind speed 05km/h and wind direction NE/SW. smell was due to loading of ammonia at Storage.
DEC Niemand attended and recorded a reading of zero at 20:53.
DEC Niemand attended.
Ammonia smell
Dets, AEL, employees (Maluleka C and Masombuka S) complained of the smell of ammonia.
DEC Hatting attended.
Environmental group paged
@ 20:18
13/02/2012 @ 20:20
Environmental group paged
OB 371/02/12 Cause of smell was due to a valve on a rail tanker at Ammonia Storage plant not being closed properly. W/S 6km/hr ; W/D NE-SW. The valve was closed and there was no ammonia smell thereafter.
27.03.2012 @14:36
12/04/2012 @ 19:05
Smell related to a spill or leak
Sandra Wright from Afrifil in Founders View North complained about a very bad smell which was suspected of coming from a spill or leak from the AEL site.
DEC attended in the afternoon and collected a water sample from the drain. E. van Dongen, AEL Group Environment Manager, visited Afrifil and investigated the complaint on 28.03.2012
The smell was due to sewage from the Founders View North Estate being discharged into a storm water drain most probably through an incorrect connection from the building or a broken sewer pipe.
Chemical smell
A strong chemical smell was reported in the Terenure area.
DEC Hatting attended. Checked the factory and surrounding area.
The chemical smell was coming from the Tembisa and Chloorkop area. W/S 13km/hr ; W/D N/S.
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Date/time
Complaint /
Complainant /
Incident
Reporter
Action taken
Feedback
Environmental group notified OB 322/04/12 05/05/2012
Ammonia smell
@01:22
A smell of ammonia was reported by a Stallion security officer in the Modderfontein Industrial Complex.
DEC Barnard attended
The smell was coming from a small leakage of vapor from a top valve of a road tanker. The tanker was sent back to ammonia storage for offloading. Environmental group notified
12/06/2012 @ 07:36
12/06/2012 @ 10:36
04/07/2012 @ 13:56
05/07/2012 @ 08:00
12/10/2012
Ammonia smell
Ammonia smell
Ash complaint
cloud
Ammonia smell
Ammonia smell
A strong ammonia smell was reported by Seshni Pather at Senet, Modderfontein.
DEC Hatting attended and contacted ammonia storage who confirmed that the smell was due to offloading at storage
Report back given to Seshni
R. Richmond from the explosives lab in the Modderfontein Industrial Complex reported an ammonia smell at ANS 1
The smell was due to incorrect ratio settings for ammonia, nitric acid and water resulting in the acid mixture being vented into the air. ANS was taken offline and Ekurhuleni Emergency Services and surrounding communities notified.
Mrs English of Esther Park complained of a black cloud of ash dust at the Ash Dams 4 & 5 area (Heartland).
DEC Niemand attended and upon investigation found that GQ Projects were digging and loading ash without consent. This caused the dust clouds at Ash Dam 4 and 5. Wind strength and direction 16.8km/h NW –SE
Feedback was given to the complainant.
Irene Hazi of Daniel Italy Design, and Diana of Card Technologies in Moddercrest Office Park, and Goodwill Magidigidi of Heartland all complained of strong Ammonia smell at and around Moddercrest Office Park area
DEC Martin Niemand investigated and reported no smell. Storage and Distribution and all nitrates plants were called and confirmed that no spillage occurred and operations were normal. Wind strength & Direction 10km/h E-W
Feedback given complainants.
Christo of Trendcon reported a strong ammonia smell at Ammonia
DEC de Villiers attended. No ammonia readings
Feedback complainant
Environmental group notified OB: 630/06/12.
Environmental group notified OB 374/06/2012
Environmental group notified OB no 097/07/12
to
all
Environmental group notified OB no 106/07/12
given to Environmental
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Date/time
Complaint /
Complainant /
Incident
Reporter
@11:55
13/01/2013
Alley road.
group notified
DEC Niemand attended. W/S 16 Km/hr. W/D NE/SW
Environmental group notified. OB581/01/20
Michael Borman of Kestrol Place reported the smell of ammonia.
DEC Hattingh attended.No readings obtained in Moddercrest area. The smell could have been due to the ammonia blending process at ANS 2
Environmental group notified.
Keith Breslar from Birch Acres complained of a bad smell
DEC Hattingh attended and investigated. Smell came from Chloorkop
Feedback given to complainant . Environmental group notified
Chresto of RVI reported the smell of ammonia in the 4 Ammonia area, due to a pop-up relief valve that lifted at ANS plant
03/06/2013 @ 18:50
Ammonia smell
04/08/2013
Bad Smell
Feedback
obtained attended. Wind speed and direction:10km/h N-S
Ammonia smell
@11:10
Action taken
OB 299/10/2012
OB:081/06/2013
OB 092/08/13 10/09/2013 @15:45
28/10/2013 @ 10:59
28/10/2013 @ 14:28
Bad smell burning oil
Ammonia smell
Smoke
of
Complaint of bad smell of burning oil received from Stanley at Loofboom Street in Terenure
DEC Plillay attended at 16:08. The gas Analyzer showed no readings. Wind speed: 19 Km/Hr; wind direction: NW/SE. Feedback given to complainant It is unlikely that the emission came from the Modderfontein Industrial Complex
Feedback given to complainant. Environmental group notified
Christo Steyn from RVI, a tenant in the OLD 4 Ammonia in Modderfontein Factory, complained of an ammonia smell
DEC Niemand attended and a reading of 0ppm ammonia was obtained. Wind speed 21 Km/Hr. Wind direction- N/S
Feedback given to complainant. Environmental group notified
Christo Steyn of RVI reported a lot of smoke behind their office block
DEC Niemand attended. It was found that L.R Simoes was working on the Nitric acid production line when they opened the flanges, some acid that was in the pipe spilled out and caused a fume-of
Feedback given to complainant. Environmental group notified
OB 215/09/13
OB 1374/2013
OB1376/2013
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Date/time
Complaint /
Complainant /
Action taken
Feedback
Incident
Reporter A strong smell of ammonia was reported by an employee at DETS campus
DEC Niemand attended. Storage informed DEC that ammonia was being offloaded and the plant just started up. Wind speed 7.5 Km/Hr. Wind direction- N/S
Environmental group notified
30/01/2014 @ 07:43
Ammonia smell
21/03/2014 @18:00
Ammonia smell
DEC Hatting reported a strong ammonia smell at the platform area.
DEC contacted Nitrates and Ammonia storage, and it was confirmed that no spillage occurred in the factory area. At 18:30 pm DEC Hatting reported that the smell faded. Wind speed: 8Km/hr. Wind Direction: N/S
Environmental group notified.
16/04/2014 @ 09:41
Ammonia smell
Mr Mark Moir from ML Fire Safety complained of a strong smell of ammonia in Moddercrest.
DEC P. Hattingh attended and obtained a reading of 5 ppm. Nitrates confirmed the start-up of ANS 2. Wind speed: 23 km/hr. wind direction: E-W
Environmental group notified.
06/05/2014 @ 08:32
Ammonia smell
Ellen van Dongen from AEL reported a strong ammonia smell at the Modderfontein Sports Club
DEC Hattingh investigated. The Analyzer picked up a reading of 10 ppm. DCS reported that ANS 2 was being started up. Wind speed: 10 km/hr. Wind direction: W-S
Feedback given to complainant. Environmental group notified
Mr. Daniel from Imvula reported a strong smell of ammonia at the old Commando building
DEC Niemand investigated. The smell was due to the start-up of ANS 1 and ANS 2 plants. WS 16 Km/hr. Wind direction NW/SE.
Environmental group notified
Mr Wolmerans of Imvula reported a white cloud coming from the factory that smelt like acid.
DEC Niemand investigated. Nitrates No 3 and 4 tripped causing the smell of acid. Wind speed 4km/hr, wind direction NW/SE.
Environmental group notified
Dalene Smith from AEL reported smoke outside East Gate. Sesfikile Transport Company (148 Oranjerivier road) was burning waste beneath overhead electric cables.
DEC Niemand attended. Fire Department then informed. Follow uprequested from Sandra (Sesfikile Transport)
Environmental group notified
22/06/2014 @ 18:08
Ammonia smell
08/09/2014 @ 17:50
Acid smell
17/12/2014 @ 06:25
Smoke
OB 138/14/2014
OB: 334/04/14
OB114/05/14
OB466/06/2014
OB106/09/14
OB 405/12/2014
Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
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Date/time
08/01/2015 @ 08:55
Complaint /
Complainant /
Incident
Reporter
Ammonia smell
Kia Ells of RVI reported a strong ammonia smell in the 4 Ammonia area.
Action taken
Feedback
DEC attended. No ammonia readings were detected. ANS 1 was being started and could have caused the smell. Wind speed 05 km/hr. Wind direction NE/SW.
Environmental group notified OB 147/01/2015
Atmospheric Impact Report: Application For Postponement of the Minimum Emissions Standards at the AEL Mining Services: Modderfontein Industrial Complex Report No.: 14AEL01
79
