air quality management report: july to september 2009 air quality reports/80906aq_sonae_july... ·...

Air Quality Management Report:

July to September 2009

Sonae Novobord

WSP Document Reference

Footer Title

QM

Issue/revision Issue 1 Revision 1 Revision 2 Revision 3

Remarks Draft 1 Draft 2 Draft 3 (Final)

Date Feb 2010 Feb 2010 April 2010

Prepared by L MacGregor L MacGregor L MacGregor

Signature

Checked by A Simpson A Simpson A Simpson

Signature

Authorised by A Simpson A Simpson A Simpson

Signature

Project number 80906AQ 80906AQ 80906AQ

File reference 80906AQ_Draft1 80906AQ_Draft2 80906AQ_Draft3

WSP House 1 on Langford Langford Road Westville Durban 3629 Tel: +27(0) 31 240 8860 Fax: +27(0) 31 240 8861 http://www.wspgroup.co.za Reg. No: 1995/08790/07

Contents

EXECUTIVE SUMMARY 1

1 Introduction 2

2 The Regulatory Framework for Air Quality 2

3 Air Quality Study Methodology 5

4 Results 7

5 Conclusion 14

AQ Management Report: July to September 2009 80906AQ 1

Executive Summary

WSP Environment and Energy was requested to monitor various air quality impacts in and around the Sonae

Novobord (Pty) Ltd - White River plant. For the three month period from July to September 2009, two key pollutant

parameters were monitored, namely; particulate matter (PM10), and dust deposition (fallout). The two parameters were

monitored in terms of the current SA Regulatory framework where applicable. Two sets of formaldehyde samples are

due to be deployed prior to the end of 2009, but will be reported on the next quarterly report.

Despite further technical problems, the OsirisTM

dust monitor gathered sufficient data to show 24-hour periods of high

concentration, followed by 24-hour periods of compliance with acceptable PM10 concentrations. Such trends indicate

that the plant is subject to variable operating conditions and that the wind field (dispersion potential) is variable. The

PM10 graph displays the time period pre- and post-commissioning of the new dryer, with a few days gap in the data

experienced due to the plant being shut down and the electricity supply to the instrument being cut off. The results

show a slight improvement in fenceline PM10 concentrations post-installation, but exceedences of the legislated

NEM:AQA interim limit of 180 µg/m3 over a 24-hour period were still measured. Technical problems with the new dryer

were attended to and largely resolved within a few weeks of first commissioning, which is typical for new plant

installation. Future monitoring results are required to demonstrate whether the dryer achieves the desired net positive

impact on the fenceline and beyond (i.e. in reducing environmental particulate concentrations).

When compared to the previous three month investigation, it appears that there is an increase in dust deposition,

which can be attributed partly to variance in seasonal climatic conditions. This three month period is characterised by

increasingly dry and slightly windier conditions; September typically experiencing the highest wind speeds across the

Lowveld. The PM10 concentrations recorded at the plant are in some instances not within the current legal limits for

ambient air, and this situation is likely to present more problems once more stringent legislation is enforced at the

beginning of 2010. Continued efforts will be required on the part of Sonae Novobord to further reduce all particulate

emissions in order to stay compliant with tightening legislation. It is expected that results will improve post-

commissioning of the new dryer at the plant, but further monitoring at the three fenceline sites prescribed in the AQMP

and ROD is required to make valid conclusions.


1 Introduction

Sonae Novobord (Pty) Ltd (hereafter referred to as Sonae Novobord) produces wood based panel products,

specifically a medium density fibre board (MDF) and particle board (PB) at their Rocky Drift factory in White River,

Mpumalanga. The plant is located on Portion 3 of the Farm Dingwell 276 JT and Portion 5 of the remainder of the

Farm Paarlklip 280 JT in Rocky Drift on the R40 between Nelspruit and White River. Sonae Novobord falls within the

Mbombela Local Municipality which form part of the Ehlanzeni District Municipality. Sonae Novobord has another

factory which produces wood based panel products in Panbult, Mpumalanga. The PB and MDF is utilised by the

building industry, furniture manufacturers, kitchen manufacturers, shop fitting, coffins, DIY, etc and niche markets.

As part of Sonae Novobord’s commitment towards achieving environmental compliance, WSP Environment and

Energy has been contracted to monitor various aspects in and around the White River plant in terms of air quality. For

this particular three month monitoring period, two parameters were monitored, namely particulate matter (PM10), and

dust deposition (fallout). The two parameters were monitored in terms of the current SA Regulatory framework and

guidelines where applicable.

2 The Regulatory Framework for Air Quality

The new National Environmental Management: Air Quality Act 39 of 2004 (NEM:AQA), which repeals the Air Pollution

Prevention Act of 1965, came into effect on 11 September 2005 with exclusions of certain sections such as the

licensing of listed activities. Until these sections are included, the relevant sections of the Air Pollution Prevention Act

will remain in force. Key features of the new legislation include:

� Decentralizing air quality management responsibilities;

� Requiring significant emission sources to be identified, quantified, and addressed;

� Setting ambient air quality targets as goals for driving emission reductions;

� Recognizing source-based (command-and-control) measures in addition to alternative measures, including market

incentives and disincentives, voluntary programmes, and education and awareness;

� Promoting cost-optimized mitigation and management measures;

� Stipulating air quality management planning by authorities, and emission reduction and management planning by

sources; and

� Providing for access to information and public consultation.

The new Act introduces a system based on ambient air quality standards and corresponding emission limits to achieve

them. Existing ambient air quality guidelines are viewed as inadequate to protect people’s health and well-being. With

the exception of sulphur dioxide (SO2), South Africa’s limits for particulates (PM), nitrogen dioxide (NO2), ozone (O3),

lead (Pb) are more lenient than internationally accepted health thresholds. Although updated air quality limits for

common pollutants have been published by the South African Bureau of Standards (SABS), DEAT has not yet

adopted them.

Linked to the new Air Quality Act are two standards set by the South African National Standards (SANS), namely

SANS 69 (Framework for setting and implementing national ambient air quality standards) which defines the basic

principles of a strategy for ambient air quality management in South Africa, and SANS 1929:2005, which gives limit

values for common pollutants.

SANS 69, (Framework for setting and implementing national ambient air quality standards), makes provision for the

establishment of air quality objectives for the protection of human health and the environment as a whole. Such air

quality objectives include limit values, alert thresholds and target values.

In SANS 1929: 2005 it states that SANS 69 makes provision for establishing air quality objectives for the protection of

human health and the environment, and stipulates that limit values are initially set to protect human health. The setting

of such limit values represents the first step in a process to manage air quality and initiate a process to ultimately


achieve acceptable air quality nationally. The limit values presented in this standard are intended as information to be

used in air quality management but are not enforceable until such time as time frames for achieving compliance have

been determined. This process is underway and Government Notices are currently being issued in draft form. The limit

values presented in the standard can therefore not be viewed in isolation, but should be seen as one part of an air

quality management programme.

It is envisaged that the final revisions of this standard will include margins of tolerance, compliance time frames and

permissible frequencies that limits may be exceeded, once the required assessments have been completed. SANS

1929:2005 (Ambient Air Quality - Limits for Pollutants of Concern) gives limit values for common air pollutants to

ensure that the negative effects of such pollutants on human health are prevented or reduced.

With regard to the setting of limit values for particulate matter, SANS 1929: 2005 recognises the following:

� different types of particles can have different harmful effects on human health;

� there is evidence that risks to human health associated with exposure to man-made PM10 are higher than risks

associated with exposure to naturally occurring particles in ambient air; and

� as far as they relate to PM10, action plans and other reduction strategies should aim to reduce concentrations of

fine particles as part of the total reduction in concentrations of particulate matter.

A summary of various PM standards both locally and internationally are presented in Table 1 below. These values are

expressed in µg/m³.

Table 1 Summary of the key local and international ambient standards for PM10.

AMBIENT STANDARDS

NEMA:AQA(2004)

Proposed NEMA:AQA

(2009)

SANS 1929 (2005) and

Draft Revised (2009)

US EPA (NAAQS)

EU (directive) WHO

PM10 180µg/m3

(24-hr); 60µg/m

3

(Annual)

75µg/m3 (24-hr);

40µg/m3 (Annual)

75µg/m3 (24-hr);

40µg/m3

(Annual)

150µg/m3

(24-hr) 50µg/m

3 (24-

hr); 40µg/m3

(Annual)

50µg/m3 (24-

hr); 20µg/m3

(Annual)

Target values for particulate matter (expressed in µg/m³) have also been set out in SANS 1929:2005 (Table 2).

Initially the SANS Limit Values in Table 1 will apply and industry will be required to work progressively towards the

future stricter Target values in Table 2. It must be noted, however, that from a legal standpoint, only standards

promulgated under the National Environmental Management: Air Quality Act are enforceable.

Table 2 Guideline target values for particulate matter (PM10) (SANS 1929: 2005)

Exposure Periods Averaging

Period Target Value

Daily limit for protection of health

24 hrs

50 µg/m³ (permissible frequency for

exceeding limit values to be determined)

Annual limit for protection of health

calendar year 35 µg/m³

Dust deposition, commonly referred to as fallout or nuisance dust, has been observed to be of concern at and around

the Sonae Novobord site. SANS 1929: 2005 also sets out dust deposition rates, expressed in units of mg·m-2

·day-1

over a typical 30-day averaging period. Dust deposition must be evaluated against a four-band scale as presented in

Table 3.


Table 3 Dust Deposition Rates (SANS 1929: 2005)

Band Description Label

Dust Rate, D (mg.m

-2.day

-1)

Comment

Residential D <600 Permissible for residential and light commercial

Industrial 600 < D < 1 200 Permissible for heavy commercial and industrial

Action 1 200< D < 2 400 Requires investigation and remediation if two sequential months lie in this band, or more than three occur in a year

Alert 2 400 < D Immediate action and remediation required following the first incidence of dust fall rate being exceeded. Incident report to be submitted to relevant authority


3 Air Quality Study Methodology

3.1 SUSPENDED PARTICULATE MATTER (PM10)

Continuous dust sampling was carried out using a continuous environmental air quality instrument, OsirisTM

continuous

dust monitor. The OsirisTM

is capable of measuring a number of size fractions simultaneously, namely TSP, PM10,

PM2.5 and PM1. The instrument is also equipped with a wind monitor that allows for emissions to be correlated with

wind speed and wind direction data, making it possible for recorded dust emissions to be traced back to the probable

source of the emissions. The OsirisTM

was deployed for three months, with the instrument located near the main gate

car park (as was the case in previous months). This site has historically been the dustiest part of the plant fenceline,

directly downwind of the plant assuming typical easterly winds. This worst-case scenario was also confirmed by

dispersion modelling.

Figure 1: Location of the Osiris™ continuous dust analyser adjacent to the Sonae Novobord car park. This is a leased unit which required temporary covering for additional protection against the weather. The wind monitor is setup above the instrument to record exact vectors prevailing during recorded dust concentrations.

3.2 DUST DEPOSITION

An ongoing dust monitoring programme has been implemented using the dust deposition gauges (dust buckets). The

dust monitoring forms part of Sonae Novobord’s Environmental Management Programme (EMP) and will extend

beyond the duration of this air quality assessment. The sample points for the dust deposition gauges are indicated in

Figure 2. The dust deposition gauges collect fallout dust from all sources, being non-directional samplers. In order to

quantify the proportion of wood dust in the total dust sample, the dust sample was weighed and the carbonaceous

material burned-off at approximately 500°C in a loss on ignition (LOI) test. The residual component is considered to be

largely inorganic material (rock dust).


Figure 2: Sampling positions for dust deposition gauges at the Sonae Novobord White River facility. SNBAQ01-08 indicate fenceline sites whilst SNBAQ09-11 indicate community sites. The annual wind rose for 2009 has been included on the image to reveal the dominant easterly and north easterly nodes.


4 Results

4.1 METEOROLOGICAL DATA ANALYSIS

A fully equipped Davis Vantage Pro II meteorological station has been deployed on site since 2007, which

continuously measures a range of meteorological parameters. This assists with interpretation of the recorded levels of

monitored pollutants. The graph below shows the daily rainfall, average temperature and relative humidity for the study

period.

Climatic Summary Graph: July to September 2009

0

5

10

15

20

25

30

2009/07/01

2009/07/05

2009/07/09

2009/07/13

2009/07/17

2009/07/21

2009/07/25

2009/07/29

2009/08/02

2009/08/06

2009/08/10

2009/08/14

2009/08/18

2009/08/22

2009/08/26

2009/08/30

2009/09/03

2009/09/07

2009/09/11

2009/09/15

2009/09/19

2009/09/23

2009/09/27

Ra

infa

ll a

nd

Ce

lciu

s (⁰

C ;

mm

)

0

10

20

30

40

50

60

70

80

90

100

Pe

rce

nta

ge

(5

)

Rainfall Temperature Humidity

Figure 3: Graph showing daily rainfall, average temperature and relative humidity for the study site for the months of

July, August and September 2009.

Figure 3 displays a number of rainfall events typically associated with frontal systems during the third quarter of every

year. Temperature shows a gradual increase with the onset of spring, although relative humidity is typically erratic

(being relative as opposed to absolute). The frequency of frontal systems peaks during these three months where

episodes of dry hot weather are followed closely with periods of cold (often wet) conditions. Such weather conditions

can often result in the ‘dustiest’ time of year.

Figure 4 depicts monthly wind roses from the on-site meteorological station for July, August and September

respectively. Following from discussion in the previous report, the changing wind field with the end of winter and onset

of spring winter is noteworthy, with westerly and west-southwesterly winds remaining dominant in July (although with

lower wind speeds than June), and a return to the dominance of more characteristic easterly and northeasterly winds

in August and September. Wind speeds are actually noted to be lower than for the preceding three months, although

the difference is not substantial. Based on the annual wind rose that has been established for the area over many

years, the above roses confirm that that the dominant westerly winds are winter feature only, prevailing for a relatively

small portion of the year. This shift in direction for the winter months is, however, useful to explain dust deposition

trends, with SNBAQ5 continuing to receive higher fallout during this quarter (refer to Figs. 6, 7 & 8). These trends will

also be taken into account when the dispersion model is re-run with a full year of annual sequential data, although it

will actually result in better long-term dilution of plumes that was predicted in the EIA Specialist Study, as the

pollutants are dispersed over a greater arc (in more different directions).


Figure 4: Monthly wind roses compiled from the on-site meteorological station at the Sonae Plant in Rocky Drift.

July 2009

0

0

3

1.5

6

3.1

10

5.1

16

8.2

(knots)

(m/s)

Wind speed

0°

22.5°

45°

67.5°

90°

112.5°

135°

157.5°

180°

202.5°

225°

247.5°

270°

292.5°

315°

337.5°

30

60

90

120

August 2009

0

0

3

1.5

6

3.1

10

5.1

16

8.2

(knots)

(m/s)

Wind speed

0°

22.5°

45°

67.5°

90°

112.5°

135°

157.5°

180°

202.5°

225°

247.5°

270°

292.5°

315°

337.5°

30

60

90

120

150

September 2009

0

0

3

1.5

6

3.1

10

5.1

16

8.2

(knots)

(m/s)

Wind speed

0°

22.5°

45°

67.5°

90°

112.5°

135°

157.5°

180°

202.5°

225°

247.5°

270°

292.5°

315°

337.5°

30

60

90

120

150


4.2 SUSPENDED PARTICULATE MATTER (PM10)

The OsirisTM

continuous dust monitor is capable of measuring a number of size fractions simultaneously, namely TSP,

PM10, PM2.5 and PM1, however only PM10 is graphed as this is the size range for which health effects are

internationally accepted and therefore used for assessment of compliance in South African standards for ambient air.

The instrument is also equipped with a wind monitor that allows for emissions to be correlated with wind speed and

wind direction data, making it possible for recorded dust emissions to be traced back to the probable source.

A conservative approach was implemented with the OsirisTM

instrument positioned near to the main entrance car park

as this area has historically shown to reveal the highest fenceline dust and PM10 concentrations at the plant (i.e.

‘worst-case scenario’). However, due to a number of technical reasons, the OsirisTM

was not able to run effectively

throughout the survey period, so the results depicted in Figure 5 cover the period between 17 July and 30 August.

This period is significant, as it covers the final operation of the old dryer and the commissioning phase of the new

dryer.

Figure 5: 24-hour PM10 averages at the plant for the period between 17 July and 30 August 2009.

The PM10 data shown above (Fig. 5) indicates two to three days of low concentrationse interspersed with single days

where levels exceeded the limit of 180 µg/m3 over a 24-hour period. There is an allowance for 4 exceedences over

one year, however this short monitoring period already displays twelve instances where this limit has been exceeded.

This is a cause for concern where concentrations of PM10 have reached particularly high levels of over 400 µg/m3 for a

single 24-hour period, although this would have been during the run-out phase of the old dryer or commissioning of

the new dryer. It is also expected that the number of exceedences may increase over the duration of the winter and

early spring season where fugitive dust and veld fires are likely to exacerbate smoke and dust (TSP) problems around

the plant.

The gap in data from the 15th to 19

th August is concurrent with the time when the new dryer was commissioned (on 1

August). The gap in data for this period was due to the plant shut down where the electricity was turned off for a few

days which also cut the power to the OsirisTM

. According to the plant Environmental Officer, the facility experienced

some problems once the plant resumed operation as the installation and operation of the new dryer required


adjustments. Despite this, a clear decrease in 24-hour averages can be noticed in Fig. 5. The setup problems

experienced at the plant during the commissioning of the new dryer can be seen by the 24-hour exceedences. One

would expect that such exceedences are likely to decrease once the new dryer is operating efficiently and according

to manufacturer specification.

Specific details of each exceedence event are given below:

• 23/07/2009: 24-hr average PM10 concentration = 416 µg/m3. Peak concentrations occurred from 03h00 until

07h00. Calm winds were blowing from off-site (290° / WNW) during this period which suggests that the

fenceline concentration was not caused exclusively by emissions from the Sonae plant. The Environmental

Officer (EO) also noted that there were veld fires in the area which would have contributed to ambient smoke

(and therefore PM10) concentrations. Given the low wind speeds and direction, it is suspected that some dust

may also have originated from the truck loading area immediately to the NW of the analyser.

• 27/07/2009: 24-hr average PM10 concentration = 283 µg/m3. Peak concentrations were recorded between

09h00 and 16h00. Winds of increasing strength were blowing from on-site (90° / E) during this period which

suggests that the fenceline concentration was caused by fugitive and point source emissions on the Sonae

plant. However, the EO also observed that the cement packers to the east of the Sonae plant were busy

stripping out silos, so it is likely that this source also contributed to the measured ambient dust load, being

directly upwind.


05h00 and 07h00. Gentle winds were blowing from off-site (247.5° / WSW), which suggests that the fenceline

concentration was not caused directly by emissions from the Sonae plant. This vector points towards the light

industrial area to the southwest of the Sonae plant which must be the suspected source. The consultant has

previously inspected this area and found there to be several small-scale but uncontrolled sources.


05h00 and 10h00. Moderate winds were blowing from off-site (270° / W), which initially suggests that the

fenceline concentration was not caused directly by Sonae activities. However, it is recorded by the EO that

the commissioning of the new dryer was taking place and the discharge dump was only 10m from the AQ

analyser. It is suggested that such a proximal emission point must have contributed to the dust recorded by

the instrument, and may have caused a nuisance to nearby receptors. The close proximity also, however,

dictates that the measurements cannot be regarded as representative of the ambient environment for

assessment of health effects.

• 06/08/2009: 24-hr average PM10 concentration = 270 µg/m3. High concentrations were recorded intermittently

between 11h00 and 20h00. Moderate to strong winds were blowing from a narrow range on-site (67.5° to 90°

/ ENE to E) so the source was clearly from Sonae and most likely from the discharge dump of the new dryer

as noted by the EO.


between 06h30 and 08h40. Very calm conditions prevailed, so it is suggested that the on-site discharge dump

was again responsible for the elevated dust concentrations.


between 13h00 and 18h30. Moderate to strong winds blowing from on-site (90° / E) prevailed, so it is

suggested that the on-site discharge dump was again responsible for the elevated dust concentrations.


between 12h00 and 18h00. Strong winds blowing from on-site (90° / E) prevailed, so it is suggested that the

on-site discharge dump was again responsible for the elevated dust concentrations.


20h00 and 00h00. Calm conditions prevailed with a gentle breeze blowing from on-site (112.5° / ESE) again

suggesting that the discharge dump from the new dryer was responsible for the elevated dust concentrations.


18h00 and 21h00. Calm conditions prevailed with a gentle breeze blowing from on-site (90° / E) again

suggesting that the discharge dump from the new dryer was responsible for the elevated dust concentrations.



02h00 and 09h30. Calm conditions prevailed with a gentle breeze blowing from off-site (247.5° / WSW), but

little cognisance should be given to the wind vector with such gentle air movement (as described for

02/08/2009), so it can again be surmised that the commissioning of the new dryer was the primary source.


12h00 and 13h30, then again between 20h30 and 22h30. Gentle to moderate winds were blowing from on-

site (45° to 90° / Ne to E) during both periods which suggests that the fenceline concentration was again

attributable to on-site sources, most likely the discharge pump.

The wind speed descriptions used in the above text are not standard meteorological classifications as they relate to dispersive conditions for fine dust, so the approximate wind speeds to which they relate are tabulated below.

Table 4 Wind speed classes for dispersion of fine dust

Wind Speed Description

Wind Speed (m/s)

Wind Speed (km/h)

Calm < 0.5 < 1.8

Gentle 0.5 - 1.0 1.8 - 3.6

Moderate 1.0 - 3.0 3.6 - 10.8

Strong > 3.0 > 10.8

The above findings demonstrate that ambient exceedences are complex in nature and cannot simply be attributed to

one apparent source until the evidence is examined in detail. Hence the immense value of continuous monitoring of

both the pollutant parameter and the prevailing meteorological conditions. However, it is clear that the commissioning

of the new dryer contributed significantly to dust load on the western fenceline (and presumably beyond into the

neighbouring industrial area) throughout the month of August 2009.

Whilst these results are expected to improve post the early commissioning phase of the new dryer, an improvement in

dust suppression measures are vital for lowering ambient dust pollution on site. In summary, whilst the general trend in

PM10 concentrations post-commissioning was improving, there were still some exceedences of the legal limits; a

situation that will become more problematic as the new, more stringent limits become enforceable in early 2010.

Results for the fourth quarter (October to December 2009) should be more indicative of PM10 concentrations that are

typical of normal operation of the new dryer.

4.3 DUST DEPOSITION

Sonae Novobord has implemented an ongoing monitoring program for the assessment of nuisance dust deposition.

The reference method recommended by the SANS 1929:2005 is the ASTM D1739. This technique makes use of

fallout gauges (dust buckets), which are essentially open containers (or cylindrical buckets), filled with water and

algaecide, and left at designated sites for a stipulated timeframe to collect solid and liquid particles that are typically

greater than 10 µm in diameter.

Coarser dust particles that settle out under gravity were viewed as a cause of nuisance during site observations. Dust

gauges were deployed as indicated in Figure 2. The dust that deposits in the gauges would be from a number of

sources. The analytical laboratory was requested to quantify the proportion of carbonaceous dust in the total dust

sample as a conservative estimate of the proportion of organic (wood) to inorganic (silica) matter. To achieve this, the

total dust sample is weighed and then the carbonaceous material is burned off at 500°C in the loss on ignition (LOI)

test. The remaining sample is weighed to determine the non-combustible silica type dust and the difference in weight

compared to the original sample indicates the approximate proportion of wood dust.

Nine dust fallout buckets were placed in and around the Sonae plant as mapped in Figure 2 in order to establish dust

fallout rates for each month (and season) of the year so that these can be used as benchmark for future assessments.


The dust gauges are deployed for a period of thirty (30) days, in accordance with the requirements of SANS

1929:2005 and the results are compared with the South African limit values described in Table 1. Three further sets of

results from the ongoing monitoring program, as supplied by Talbot & Talbot (Pty) Ltd laboratories (SANS Accredited),

are shown in Figures 6, 7 and 8 below.

Dust depostition rates (July 2009)

0

200

400

600

800

1000

1200

1400

SNBAQ7

SNBAQ5

SNBAQ1

SNBAQ8

SNBAQ4

SNBAQ3

SNBAQ6

SNBAQ2

SNBAQ9

Average

Site Name

Depositio

n r

aie

(m

g/m

2/d

ay)

Inorganic (Silica)

Organic (Wood)

SANS Std: Industrial

SANS Std:Residential

Figure 6: Dust deposition rates for July 2009.

Dust Deposition Rates (August 2009)

0

200

400

600

800

1000

1200

1400

SNBAQ7

SNBAQ5

SNBAQ1

SNBAQ2

SNBAQ8

SNBAQ4

SNBAQ3

SNBAQ9

SNBAQ6

Average

Site Name

Depositio

n r

aie

(m

g/m

2/d

ay)

Inorganic (Silica)

Organic (Wood)



Figure 7: Dust deposition rates for August 2009.


Dust Deposition Rates (September 2009)

0

500

1000

1500

2000

2500

3000

3500

4000

SNBAQ1

SNBAQ7

SNBAQ5

SNBAQ8

SNBAQ9

SNBAQ3

SNBAQ4

SNBAQ2

SNBAQ6

Average

Site Name

Depositio

n r

aie

(m

g/m

2/d

ay)

Inorganic (Silica)

Organic (Wood)



Figure 8: Dust deposition rates for September 2009.

The above figures 6 to 8 reveal that the organic portion (wood dust) of the fallout makes up a significant proportion (>

50%) of the total insoluble dust captured at these sites. This indicates that the larger component of the dust fallout is

from wood processing such as that from the Sonae Novobord plant, although there is a significant contribution from

inorganic matter. This silica type dust in the sample is likely to originate from a combination of the natural environment

and from some neighbouring activities. These results reflect three consecutive months of measurement, and although

the initial results indicate that the rates are below the SANS 1929:2005 industrial recommended limit.The averages for

each month suggest that the bucket sites are all compliant, with the exception of September, where a single bucket

sample (SNBAQ1) recorded exceptionally high levels of dust which increased the overall monthly average by a

significant portion. It is suspected that the SNBAQ1 bucket sample may have been tampered with. A possible

explanation is that unknown persons threw sand into the bucket; WSP has based this assumption on the fact that such

an elevated rate has never been recorded on site and a vagrant has been noticed nearby on several occasions.

The three highest fallout values are associated with SNBAQ1, SNBAQ7 and SNBAQ5, which is consistent with the

previous report (April, May & June 2009). These higher dust fallout rates are a result of different factors; SNBAQ7 is

immediately adjacent to the chipper and stockpiles (i.e. proximity), SNBAQ5 is adjacent to disturbed land and some

neighbouring sources (proximity to inorganic sources – note lower contribution of wood dust) and downwind of Sonae

sources for winter months (refer Fig. 4 and discussion), whilst SNBAQ1 is downwind of the stacks and fugitive sources

under northeasterly wind conditions that became dominant in September.

The dust fallout results are slightly higher for this investigation than those obtained in the previous quarterly study, but

this is at least partly as a result of seasonal variance. More conclusive trends can be deduced once there is a full year

of baseline data.


5 Conclusion

Continuous dust monitoring showed several 24-hour periods of high PM10 levels interspersed with longer periods of

low concentrations. The trend of periods of low concentrations mixed with periods of higher concentrations indicates

that the plant is subject to upset operating conditions and variable dispersion conditions. Continued efforts will be

required on the part of Sonae Novobord to further reduce emissions of all particulate matter. With the commissioning

of the new dryer, a slight improvement was noticed in PM10 concentrations at the plant despite the problems

experienced with the installation phase. It is anticipated that the PM10 concentrations will decrease further once

efficient running of the new dryer is achieved. Ongoing measurement will either confirm or refute this expectation.

When compared to the previous investigation (April, May & June 2009) it does appear that there is an increase in dust

fallout which could be largely attributed to seasonal variance and the commissioning problems with the new dryer. It

must be noted from observation that there is an improvement in house keeping at the plant. However, there is still

scope for further improvement, such as covering of stockpiles. Ongoing measurements through spring will clarify the

efficacy of mitigation measures and any reduced impact of the new dryer once it operates according to manufacturer’s

specification.

In conclusion, Sonae Novobord requires continued efforts in addressing current emissions from the plant if more

stringent future standards and requirements are to be met. More conclusive remarks on mitigation measures can be

made with ongoing monitoring of emissions and resultant fenceline and ambient concentrations. Two formaldehyde

surveys will be conducted before the end of the year and these will assist in assessment of the overall air quality

impact of the new plant in full operation.

References Republic of South Africa (1965). Atmospheric Pollution Prevention Act, No. 45 of 1965. Available online at:

http://www.environment.gov.za

Republic of South Africa (2004). National Environmental Management: Air Quality Act, No. 39 of 2004. Available

online at: http://www.environment.gov.za

Standards South Africa (2005). Ambient air quality – Limits for common pollutants. South African National Standard

1929:2005.

WSP (2008). Specialist Air Quality Study Sonae Novobord May 2008. EIA Specialist Report-Unpublished.

WSP (2009). Air Quality Management Report: April to June 2009: Sonae Novobord. Unpublished.

air quality management report: july to september 2009 air quality reports/80906aq_sonae_july... ·...

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