XARIS ENERGY (PTY) LTD

XARIS ENERGY (PTY) LTD

SPECIALIST STUDY: Noise Impact

PREPARED BY: Dr. Brett Williams

ENVIRONMENTAL NOISE IMPACT STUDY

FOR THE PROPOSED XARIS ENERGY FSRU AND POWER

GENERATION PROJECT – WALVIS BAY NAMIBIA

ESIA FOR THE PROPOSED DEVELOPMENT OF THE XARIS ENEREGY WALVIS BAY POWER PLANT PROJECT

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COPYRIGHT:

PROJECT NAME Xaris Energy Walvis Bay Power Plant and Gas Supply

Facility

STAGE OF REPORT Final Noise Impact Study

CLIENT Xaris Energy (Pty) Ltd

SPECIALIST CONSULTANT Brett Williams

DATE OF RELEASE 10th April 2015 (Version 4)

CONTRIBUTORS TO THE REPORT -

CONTACT [email protected]

+27 (0)41 3656846

mailto:[email protected]


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DECLARATION

I hereby declare that I do:

(a) have knowledge of and experience in conducting specialist assessments, including

knowledge of the Environmental Management Act (Act 7 of 2007)and the

Regulations and Guidelines that have relevance to the proposed activity;

(b) perform the work relating to the application in an objective manner, even if this

results in views and findings that are not favourable to the applicant;

(c) comply with the abovementioned Act, its Regulations, Guidelines and other

applicable laws.

I also declare that there is, to my knowledge, no information in my possession that

reasonably has or may have the potential of influencing –

(i) any decision to be taken with respect to the application in terms of the Act and its

Regulations; or

(ii) the objectivity of this report, plan or document prepared in terms of the Act and its

Regulations.

Dr Brett Williams


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EXECUTIVE SUMMARY

Safetech were requested to conduct a noise impact assessment for the construction

and operation of the proposed Xaris Energy FSRU and Power Generation Facility in

Walvis Bay, Namibia.

The following conclusions can be drawn from the results of the study:

There will be a short-term increase in noise in the vicinity of the site during

construction, as the ambient level will be exceeded in areas very close to the

two construction sites. The impact will however not be significant due to the short

duration;

The noise impact from the Power Plant and FSRU will be minimal due to the

distance from the nearest noise sensitive human receptors;

The noise impacts from the decommissioning and rehabilitation of the site will be

of short term nature and the will be similar to the construction phase.

The IFC Environmental Noise Guidelines require a residential daytime limit of 55dB(A)

and a night time limit of 45 dB(A) for industrial projects. The night and daytime limit is

not exceeded.

The SANS 10103:2008 “Rural” noise limits are more stringent limits than the IFC noise

emission limits used in the study in the absence of Namibian noise limits. The SANS

daytime of limit of 45dB(A) and a night time limit of 35 dB(A) was applied for the

FSRU due to the FSRU being located closer to residents than the Power Plant. The

predicted FSRU operations met the SANS10103:2008 limits at the closest human

receptors. The SANS 10103:2008 “Industrial” limits were met at the Power Plant. No

noise sensitive receptors were identified within close proximity to the proposed

Power Plant.


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TABLE OF CONTENTS

EXECUTIVE SUMMARY .............................................................................................................. iii

TABLE OF CONTENTS ............................................................................................................... iv

ABBREVIATIONS AND ACRONYMS ........................................................................................ vi

1 BACKGROUND ................................................................................................................... 8

1.1 Introduction ................................................................................................................. 8

1.2 Specialist Study Leader .............................................................................................. 8

1.3 Terms Of Reference .................................................................................................... 8

1.4 Methodology ............................................................................................................... 9

1.4.1 Desktop study methodology .............................................................................. 9

1.4.2 Field Study ............................................................................................................. 9

1.5 Assumptions And Limitations ................................................................................... 12

2 PROJECT DESCRIPTION .................................................................................................... 13

2.1 POWER PLANT ............................................................................................................ 13

2.2 FSRU............................................................................................................................. 13

3 LEGAL AND REGULATORY REQUIREMENTS ................................................................... 13

4 THE RECEIVING ENVIRONMENT ...................................................................................... 15

4.1 Sensitive Receptors ................................................................................................... 15

4.1.1 Human Sensitive Receptors .............................................................................. 15

4.1.2 Natural Environment Receptors ....................................................................... 16

4.2 Results of the field study ........................................................................................... 17

4.3 Environmental Vulnerability ..................................................................................... 17

5 NOISE IMPACT ASSESSMENT ............................................................................................ 19

5.1 Noise Impact during the Construction Phase ....................................................... 19

5.1.1 Conclusion - Construction Noise ..................................................................... 20

5.2 Noise Impact of the Gas Power Station ............................................................... 20

5.2.1 Conclusion – Power Plant ................................................................................. 25

5.2.2 Conclusion – FSRU .............................................................................................. 25

5.3 Assessment of Noise Impact.................................................................................... 26

5.3.1 Comparison to IFC Environmental Noise Guidelines ..................................... 27

5.3.2 Mitigation - Construction................................................................................... 27

5.3.3 Mitigation - Operation ....................................................................................... 27


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5.3.4 Recommended Monitoring .............................................................................. 28

6 CONCLUSION ................................................................................................................... 28

7 REFERENCES ...................................................................................................................... 29

Appendix A – POWER PLANT LAYOUT ................................................................................. 30

Appendix B – Calibration Certificate .................................................................................. 31

Index of Tables

Table 1-1 - Meteorological parameters used in modelling ............................................... 9

Table 1-2 – Location of ambient measurement point ...................................................... 10

Table 3-1- Typical rating levels for noise in various types of districts ............................... 14

Table 4-1 Results of Field Study ............................................................................................ 17

Table 4-3 Vulnerability Rating Criteria ................................................................................. 18

Table 4-4 Vulnerability Rating .............................................................................................. 18

Table 5-1 Combining Different Construction Noise Sources – High Impacts (Worst

Case) ....................................................................................................................................... 19

Table 5-2 Combining Different Construction Noise Sources – Low Impacts ................. 19

Table 5-3 Attenuation by Distance for the construction phase (worst case) ............... 20

Table 5-4 Sound Power Levels used in the Modelling....................................................... 21

Table 5-5: Impact assessment of the proposed project ............................................... 26

Index of Figures

Figure 1-1- Locations of ambient measurement point – Power Plant ............................ 10

Figure 1-2- Locations of ambient measurement point – FSRU ......................................... 11

Figure 4-1- Location of Power Plant and FSRU ................................................................... 16

Figure 5-1 - Modelling Results – Power Plant ...................................................................... 22

Figure 5-2 - Modelling Results – FSRU .................................................................................. 23

Figure 5-3 - Modelling Results – Power Plant & FSRU ........................................................ 24


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ABBREVIATIONS AND ACRONYMS

Ambient noise

Totally encompassing sound in a given situation at a given time, and

usually composed of sound from many sources, both near and far.

Note: Ambient noise includes the noise from the noise source under

investigation.

Annoyance General negative reaction of the community or person to a condition

creating displeasure or interference with specific activities

A-weighted

sound pressure

level (LpA and

LAeq,T)

A-weighted sound level LpA which is the sound pressure level at specific

frequencies and is given using the following equation:

LpA = 10Log

OP

PA

2

Where:

PA = is the root-mean-square sound pressure, using the frequency

weighting network A

PO = is the reference sound pressure (PO = 20 μPa).

A-weighted sound pressure level is expressed in decibels dBA

Note: For clarity in this study LpA shall equal LAeq,T

dBA

The decibel is the unit used to measure sound pressure levels. The human

ear does not perceive all sound pressures equally at all frequencies. The

“A” weighted scale adjusts the measurement to approximate a human

ear response.

Equivalent

continuous

day/night rating

level (LR,dn)

Equivalent continuous A-weighted sound pressure level (LAeq,T) during a

reference time interval of 24 h, plus specified adjustments for tonal

character, impulsiveness of the sound and the time of day; and derived

from the following equation:

dB

Where:

LR,dn is the equivalent continuous day/night rating level;

d is the number of daytime hours;

LReq,d is the rating level for daytime;

LReq,n is the rating level for night-time;

Kn is the adjustment of 10 dB added to the night-time rating level.

High-energy

impulsive sound

Sound from one of the following categories of sound sources: quarry and

mining explosions, sonic booms, demolition and industrial processes that

use high explosives, explosive industrial circuit breakers, military ordnance

(e.g. armour, artillery, mortar fire, bombs, explosive ignition of rockets

and missiles), or any other explosive source where the equivalent mass of

TNT exceeds 25 g, or a sound with comparable characteristics and

degree of intrusiveness

Highly impulsive

sound

sound from one of the following categories of sound sources: small arms

fire, metal hammering, wood hammering, drop-hammer pile driver, drop

forging, pneumatic hammering, pavement breaking, or metal impacts

of rail yard shunting operations, or sound with comparable

characteristics and degree of intrusiveness

Impulsive sound Sound characterised by brief excursions of sound pressure (acoustic

impulses) that significantly exceed the residual noise

Low frequency

noise

Sound which predominantly contains sound energy at frequencies

below 100 Hz

Reference time

interval

Representative duration of time periods that are regarded as typical for

sound exposure of the community within a period of 24 h:

– Daytime: 06:00 to 22:00

– Night-time: 22:00 to 06:00


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Residual noise

Totally encompassing sound in a given situation at a given time, and

usually composed of sound from many sources, both near and far,

excluding the noise under investigation

Specific noise

Component of the ambient noise which can be specifically identified by

acoustical means and which may be associated with a specific source

Note: Complaints about noise usually arise as a result of one or more

specific noises.


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1 BACKGROUND

1.1 INTRODUCTION

Xaris Energy (Pty) Ltd has developed the Xaris Project to provide NamPower with

their required power needs of 250 MW Net Generation Capacity. The Power Project

consists of the following main elements:

A Gas Port consisting of:

o Floating Liquefied Natural Gas (LNG) Storage and Regasification – FSRU

o Sea Island – Offshore berth comprising loading platform, dolphins and

access trestle

o Gas receiving facilities and piping

Overland Natural Gas Pipelines to the Power Plant

A Power Plant using Aeroderivative Gas Turbine Technology (GE LM6000)

The planned project will impact on the environment in a number of ways and this

study only addresses the noise impact. The study was requested by the Enviro

Dynamics as part of the overall Environmental Impact Assessment for the project.

1.2 SPECIALIST STUDY LEADER

The noise impact baseline study was conducted by Dr Brett Williams who has also

conducted the following noise impact projects in Namibia:

Walvis Bay Container Terminal Extension on behalf of Namport.

Walvis Bay Desalination Plant project on behalf of Namwater.

The Sandpiper Marine Phosphate Project on behalf of Namibian Marine

Phosphate (Pty) Ltd

Gergurub Zinc Mine development by Skorpion Mining Company (Pty) Ltd

1.3 TERMS OF REFERENCE

The terms of reference for the noise impact baseline study are:

Provide a brief review of noise legislation and standards applicable in Namibia as

well as international standards and identify relevant protocols, legal and permit

requirements;

Measure the current ambient noise levels at the various component sites

comprising the project area as well.

Conduct a noise impact study of the future impact during construction of the

project infrastructure, and operation of the plant.

Assess the potential impacts of the project, and provide management actions to

avoid/reduce negative impacts or enhance benefits, as well as associated

monitoring requirements.


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1.4 METHODOLOGY

The methodology used in the study consisted of two approaches to determine the

noise impact from the proposed plant and associated infrastructure:

A desktop study to model the likely noise emissions from the site; and

Field measurements of the existing ambient noise at different locations in the

vicinity of the proposed mine.

1.4.1 Desktop study methodology

The desktop study was conducted using the available literature on noise impacts as

well as numerical calculations using the method described in SANS 10357:2004

version 2.1 (The calculation of sound propagation by the Concawe method). The

numerical results were then used to produce a noise map that visually indicates the

extent of the noise emissions from the site.

Two wind directions were used in the study, the prevailing wind from the west south-

east and an north-west wind. The summer and winter conditions that were used in

the modelling are presented in Table 1. These parameters were chosen for the

modelling data set and are thus approximations of the site conditions.

Table 1-1 - Meteorological parameters used in modelling

TEMPERATURE RELATIVE

HUMIDITY WIND DIRECTION

Summer

Conditions 20

0C 50% NE

Winter

Conditions 10

0C 80% WSW

1.4.2 Field Study

The methodology used consisted of field measurements of the existing ambient

noise at different locations in the vicinity of the proposed Gas Port and Power Plant

facility.

A field study was conducted on the 17th March 2015. The location of the ambient

measurement position is listed in Table 1-2 and shown in Figures 1-1


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Table 1-2 – Location of ambient measurement point

TEST POINT # POSITION DESCRIPTION

TP 1 22°55'24.80"S

14°31'49.39"E

Ambient test in the closest

community in proximity to the

FSRU and Gas Pipeline Servitude.

TP 2

22°57'39.85"S

14°36'10.84"E

14°36'10.84"E

Ambient test point at Dune 7

close to the Power Plant

Figure 1-1- Locations of ambient measurement point – Power Plant


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Figure 1-2- Locations of ambient measurement point – FSRU

A number of measurements were taken by placing the noise meter on a tripod and

ensuring that it was at least 1.2 m from ground level and 3.5 m from any large flat

reflecting surface.

All measurement periods were at least 10 minutes, except where indicated. The

noise meter was calibrated before and after the survey. At no time was the

difference more than one decibel (If the difference is more than 1 decibel the meter

is not calibrated properly and the measurement is discarded).

The weighting used was on the A scale and the meter placed on impulse correction,

which is the preferred method as per Section 5 of SANS 10103:2008. No tonal

correction was added to the data. Measurements were taken during the day and

night-time. The meter was fitted with a windscreen, which is supplied by the


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manufacturer. The screen is designed so as to reduce wind noise around the

microphone and not bias the measurements.

The test environment contained the following noise sources:

Vehicular traffic that included trucks and cars;

Birds;

wind noise;

The instrumentation used to conduct the study was:

Rion Precision Sound Level Meter (NL32) with 1/3 Octave Band Analyzer Serial No.

00151075;

Microphone (UC-53A) Serial No. 307806;

Preamplifier (NH-21) Serial No. 13814; and

All equipment was calibrated (see Appendix).

1.5 ASSUMPTIONS AND LIMITATIONS

The following assumptions and limitations are applicable to the interpretation of the

report:

The infrastructure layout was supplied by the client.

The operational parameters were supplied by the client.

The project will operate for 24 hours per day.

The site layout details used in the modelling is not final and the positions are thus

approximations. The effect on the results will however be negligible due to the

remoteness of the Power Plant site to the nearest receptors, and the anticipated

small changes to the equipment positions if these are moved.

The lack of detailed noise emission data and information on the FSRU operation.

The engineering details of the final equipment have not been finalised.


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2 PROJECT DESCRIPTION

Xaris Energy Namibia (Pty) Ltd proposes to import liquefied natural gas (LNG) into

the Walvis Bay area to be re-gasified for use at a power plant that will be

constructed approximately 10 km east of Walvis Bay. The development will consist of

the following components:

Floating Storage Regasification Unit (FSRU).

Light trestle and overland pipelines for transporting the gas to the plant.

An open cycle gas turbine power plant using gas turbines at a heavy

industrial zone close to the Walvis Bay airport and Dune 7 recreational area.

2.1 POWER PLANT

The power plant will operate six General Electric LM 6000 turbines. The LM6000 is a 2-

shaft gas turbine engine equipped with a low-pressure compressor, high pressure

compressor, combustor, high-pressure turbine, and low-pressure turbine. The

dominant noise source at the plant will be the turbines. Other pumps and associated

equipment are ignored for this study as the exact design details of these are not

available yet.

2.2 FSRU

A Liquid Natural Gas (LNG) tanker will offload periodically into the FSRU which will be

permanently moored approximately 3.3km from the nearest residents of Walvis Bay.

The FSRU will pump the gas to the Power Plant via a pipeline trestle.

3 LEGAL AND REGULATORY REQUIREMENTS

Namibia does not have any directly applicable noise legislation or standards that

could be applied to the project. The draft scoping report has identified that the

applicable environmental legislation places a general onus on the developer to

ensure that the environment is not affected negatively by any development.

In view of the absence of specific noise legislation the following standards have

been used to aid the study and guide the decision making process with regards

noise pollution:


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South Africa - GNR.154 of January 1992: Noise control regulations in terms of

section 25 of the Environment Conservation Act (ECA), 1989 (Act No. 73 of 1989).

South Africa - GNR.155 of 10 January 1992: Application of noise control

regulations made under section 25 of the Environment Conservation Act, 1989

(Act No. 73 of 1989).

South Africa - SANS 10103:2008 Version 6 - The measurement and rating of

environmental noise with respect to annoyance and to speech communication.

South Africa - SANS 10210:2004 Edition 2.2 – Calculating and predicting road

traffic noise.

South Africa - SANS 10357:2004 Version 2.1 - The calculation of sound

propagation by the Concawe method.

International Finance Corporation – 2007 General EHS Guidelines: Environmental

Noise.

SANS 10103:2008 provides typical rating levels for noise in various types of districts, as

described in Table 8 below.

Table 3-1- Typical rating levels for noise in various types of districts

Type of District

Equivalent Continuous Rating Level, LReq.T for Noise

Outdoors (dB(A)) Indoors, with open windows (dB(A))

Day-night Daytime Night-time

Day-night Daytime Night-time

Rural districts 45 45 35 35 35 25

Suburban districts with

little road traffic 50 50 40 40 40 30

Urban districts 55 55 45 45 45 35

Urban districts with one

or more of the

following: Workshops;

business premises and

main roads

60 60 50 50 50 40

Central business districts 65 65 55 55 55 45

Industrial districts 70 70 60 60 60 50

SANS 10103:2008 defines Daytime as 06:00 to 22:00 hours and night time as 22:00 to

06:00 hours. The applicable rating limits that were chosen for this project is the

“Industrial” limit for the power plant and “Rural” limit for the FSRU as this is the most

stringent limit.


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The rating levels in Table 3-1 above indicate that in rural districts the ambient noise

should not exceed 35 dB(A) at night and 45 dB(A) during the day. These levels can

thus be seen as the target levels for any noise emissions from an industrial operation.

Furthermore the South African noise control regulations describe a disturbing noise

as any noise that exceeds the ambient noise by more than 7dB. This difference is

usually measured at the complainants location should a noise complaint arise.

Therefore if a new noise source is introduced into the environment, irrespective of

the current noise levels, and the new source is louder than the existing ambient

environment by more than 7dB, the complainant will have a legitimate complaint.

The Noise Management guidelines in the IFC EHS Guidelines provide ambient noise

level guidelines for an area that can be classified as residential, institutional or

educational. The community areas around the mine can be classified as residential

areas. These guidelines state the equivalent one hour LAeq rating for noise should not

be greater than 55dBA during the day (07:00 – 22:00) and 45dBA during the night

(22:00 – 07:00) outdoors. Due to the sensitivity of the operations at the FSRU, the IFC

guidelines have not been used, as the South African limits are stricter.

4 THE RECEIVING ENVIRONMENT

The potential sensitive receptors are discussed below. The main noise sensitive

receptors that could be impacted by noise pollution are the terrestrial animals, the

avifauna and human receptors.

4.1 SENSITIVE RECEPTORS

4.1.1 Human Sensitive Receptors

The proposed Power Plant is located to the west of Walvis Bay in an area that has

been designated as a heavy industrial zone. There are no sensitive noise receptors

within 5km of the site. The airport is to the east and several mines to the south. The

outskirts of Walvis Bay is about 6km to the west. There are large dunes (including

Dune 7) bewteen the proposed site for the power plant and Walvis Bay

The FSRU berth is to north east of the shore line. The berth is approximately 3.5km

from the northern suburbs of Walvis Bay.


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Figure 4-1- Location of Power Plant and FSRU

4.1.2 Natural Environment Receptors

There are sensitive and proclaimed protected areas such as the Dorob National Park

in close proximity to the Power Plant site, which could be impacted upon by noise

pollution.

The FSRU is situated in a part of the bay known for marine mammal life and avifauna.

The noise impact on the marine mammals and avifauna has not been assessed as

this is beyond the area of speciality of this study.

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4.2 RESULTS OF THE FIELD STUDY

A field study was conducted on the 17th March 2015. The results are shown in Table

4-1 below.

Table 4-1 Results of Field Study

TEST POINT START

TIME

SANS

10103

GUIDELINE

NOISE

RATING

LIMIT

L90

dB(A)

LREQ.T

dB(A) COMMENTS

TP 1

Northern suburb in

close proximity to

the pipeline

servitude and the

FSRU

18:25 45 43.8 47.0 Wind @ 3.1m/s

22:10 35 38.1 39.6 Wind @ 1.9m/s

TP 2 Power Plant

14:15 70 37.9 39.3 3 trucks and 4 cars on

D1984.

23:15 60 37.9 38.4 1 truck and 1 car on

D1984.

4.3 Environmental Vulnerability

The vulnerability of the surrounding environment was scored using the vulnerability

rating in the table below. Vulnerability refers to the susceptibility of an environmental

feature to suffer harm or its inability to withstand the effects of a hostile environment

before potential impacts are taken into account.


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Table 4-2 Vulnerability Rating Criteria

VULNERABILITY

RATING CRITERIA

LOW

The environmental feature will be negligibly affected by the

potential impact and has the ability to withstand negative effects

without being adversely affected.

MEDIUM

The environmental feature will be moderately susceptible to suffer

harm and will therefore be negatively affected by the activity

albeit not adversely.

HIGH

The environmental feature will be severely affected by the

potential impact as it is highly susceptible to suffer harm and lacks

the ability to withstand the negative effects of the activity.

Table 4-3 Vulnerability Rating

COMPONENT SENSITIVITY VULNERABILITY POTENTIAL IMPACT

Surrounding

communities and

the natural

environment to

noise emissions from

the plant during

Construction

Surrounding communities

and the natural

environment could be

disturbed by the noise

Medium Noise disturbance and

annoyance

Surrounding

communities and

the natural

environment to


the plant during

Operation


and the natural




annoyance

Surrounding

communities and

the natural

environment to


the plant during

Decommissioning


and the natural




annoyance


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5 NOISE IMPACT ASSESSMENT

The data collected during the site visit and subsequent communication with the

client was used to model the future noise impact on the receiving environment.

5.1 Noise Impact during the Construction Phase

The impact of the construction noise that can be expected at the proposed site can

be used from previous projects that the author has conducted. As an example, if a

number of pieces of equipment are used simultaneously, the noise levels can be

added logarithmically and then calculated at various distances from the site to

determine the distance at which the ambient level will be reached.

Table 5-1 Combining Different Construction Noise Sources – High Impacts (Worst Case)

DESCRIPTION

TYPICAL

SOUND

POWER

LEVEL (DB)

Mobile cranes 109

Front end loaders 100

Excavators 108

Bulldozer 111

Total* 114.4

*The total is a logarithmic total and not a sum of the values.

Table 5-2 Combining Different Construction Noise Sources – Low Impacts

DESCRIPTION

TYPICAL

SOUND

POWER

LEVEL (DB)

Front end loaders 100

Excavators 108

Truck 95

Total 111.8

The information in the above tables can now be used to calculate the attenuation

by distance. Noise will also be attenuated by topography and atmospheric

conditions such as temperature, humidity, wind speed and direction etc. but this is


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ignored for this purpose. Therefore, the distance calculated below would be

representative of maximum distances to reach ambient noise levels.

The table below gives an illustration of attenuation by distance from a noise of 114dB

(Sound Power) measured at the source.

Table 5-3 Attenuation by Distance for the construction phase (worst case)

DISTANCE FROM

NOISE SOURCE (METRES)

NOISE LEVEL

DB(A)

10 86

20 80

40 74

80 68

160 61

320 54

640 47

1280 37

What can be inferred from the above table is that if the ambient noise level is at 38

dBA as measured at Test Point Number 2, the construction noise will be similar to the

ambient level at approximately 1280m from the noise source, if the noise

characteristics are similar. Beyond this distance, the noise level will be below the

ambient noise and will therefore have little or no impact. Due to the absence of

sensitive human noise receptors in close proximity to the Power Plant and FSRU, the

construction noise impact will be negligible.

5.1.1 Conclusion - Construction Noise

The predicted noise from the construction activities is unlikely to affect the residents

of Walvis Bay.

5.2 Noise Impact of the Gas Power Station

The predicted noise levels emissions were calcualted using Sound Power levels that

were provided by the client. This was to provide an estimation of the noise energy

produced by the equipment.


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The following values were used to predict the noise impact. The list below is not

exhaustive as only the major noise producing equipment was modelled based on

the limited information available.

Table 5-4 Sound Power Levels used in the Modelling

SOURCE

# DESCRIPTION

TYPICAL SOUND POWER

LEVEL (dB)

S1 LM6000 Gas Turbine Units – Six units all

operational and acoustic enclosures

fitted to each unit.

106

S2 FSRU - FSRU docked and performing

normal regasification and offloading

operations.

118

The above data was then used to calculate the noise impacts from the Power Plant

and the FSRU. The noise impacts from the operations at the Power Plant and FSRU

are shown in the figures below.


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Figure 5-1 - Modelling Results – Power Plant

Key: Green = <30 dB(A) ; Yellow = >30 dB(A); Orange = >35 dB(A); Red = >45 dB(A)

N


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Figure 5-2 - Modelling Results – FSRU


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Figure 5-3 - Modelling Results – Power Plant & FSRU


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Figure 5-4 - Modelling Results close-up of FSRU


5.2.1 Conclusion – Power Plant

The predicted noise from the Power Plant is unlikely to have any adverse effect on

Walvis Bay due to the distance (approximately 6.5 km) from the noise source.

5.2.2 Conclusion – FSRU

The predicted noise from the FSRU is unlikely to have any adverse effect on Walvis

Bay due to the distance (approximately 3.5 km) from the noise source. As can be

seen in Figure 5-4 it may be possible to hear the noise from the FSRU under light wind

and sea conditions on the shoreline. Beyond the shoreline the ambient noise will

have a masking effect and be below the predicted 35dB(A) limit.

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5.3 ASSESSMENT OF NOISE IMPACT

The noise impact summary rating of the various key issues is presented below.

Table 5-5: Impact assessment of the proposed project

POTENTIAL

IMPACT

STATUS/

NATURE EXTENT DURATION INTENSITY PROBABILITY

DEGREE OF

CONFIDENCE

SIGNIFICANCE

PRE-

MITIGATION

MITIGATION/

ENHANCEMENT

POST-

MITIGATION

CONSTRUCTION PHASE

Construction

Noise Impact Negative Local Temporary Low Improbable High Low Noise Monitoring Low

OPERATIONAL PHASE

Operational

Noise Impact

(Power Plant)

Negative Local Long Term Low Improbable High Low Noise Monitoring Low

Operational

Noise Impact

(FSRU)

Negative Local Long Term Low Improbable High Low Noise Monitoring Low

DECOMMISSIONING PHASE

Decommissioning

Noise Impact Negative Local Temporary Low Improbable High Low Noise Monitoring Low


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5.3.1 Comparison to IFC Environmental Noise Guidelines

Power Plant

The IFC Environmental Noise Guidelines require a daytime limit of 55dB(A) and a

night time limit of 45 dB(A). The daytime limit is not exceeded further than

approximately 200m from the Power Plant and the night time limit further than

approximately 580m from the Power Plant. No noise sensitive receptors were

identified within these distances to the plant.

FSRU

The IFC 55dB(A) daytime limit is not exceeded further than approximately 800m

from the FSRU and the IFC 45dB(A) night time limit further than approximately 1300m

from the Power Plant. No noise sensitive human receptors were identified within

these distances to the FSRU.

5.3.2 Mitigation - Construction

a) It is recommended that vehicles with low noise emissions be used during

construction and that these vehicles at least comply with the Namibian Road

Traffic Regulations for noise level emissions.

b) Blasting should only occur if there are no signs of marine mammals or avifauna in

the immediate vicinity of the blast area.

c) All construction personnel should be given noise pollution sensitivity training.

d) Noise emissions should be monitored during construction.

5.3.3 Mitigation - Operation

Given that it is not possible to eliminate all noise during the operational phase, the

following general recommendations are made:

a) The International Finance Corporation guidelines for noise reduction in new

developments should be implemented. These include:

Selecting equipment with lower sound power levels;

Installing suitable mufflers on engine exhausts and compressor components;

and

Where possible, installing acoustic enclosures for equipment to stop noise at

source. This is especially important on the FSRU. The intake air ducts and


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exhaust ducts as well as the gas turbine units at the Power Plant should be

attenuated.

5.3.4 Recommended Monitoring

The following noise monitoring is recommended:

a) Noise monitoring during the construction phase along the shoreline at Walvis Bay

as well as the Power Plant site boundary; and

b) Noise monitoring during the operational phase at the nearest Walvis Bay

communities to the FSRU and Power Plant.

6 CONCLUSION

The following conclusions can be drawn from the results of the study:

There will be a short term increase in noise in the vicinity of the FSRU berth and

Power Plant during construction as the ambient level will be exceeded in areas

very close to the construction sites. The impact will however not be significant

due to the short duration.

The noise impact from the Power Plant and FSRU during operations will be

minimal due to the distance from the nearest noise sensitive receptors;

The noise impacts from the decommissioning and rehabilitation of the site will be

of short term nature and the will be similar to the construction phase.


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7 REFERENCES

International Finance Corporation – 2007 General EHS Guidelines: Environmental

Noise.

South Africa - GNR.154 of January 1992: Noise control regulations in terms of section

25 of the Environment Conservation Act (ECA), 1989 (Act No. 73 of 1989)

South Africa - GNR.155 of 10 January 1992: Application of noise control regulations

made under section 25 of the Environment Conservation Act, 1989 (Act No. 73 of

1989)

South Africa - SANS 10210:2004 Edition 2.2 – Calculating and predicting road traffic

noise

South Africa - SANS 10357:2004 Version 2.1 - The calculation of sound propagation by

the Concawe method)

South Africa - SANS 10103:2008 Version 6 - The measurement and rating of

environmental noise with respect to annoyance and to speech communication.

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APPENDIX A – POWER PLANT LAYOUT


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APPENDIX B – CALIBRATION CERTIFICATE

XARIS ENERGY (PTY) LTD

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