Hanson Aggregates
Brayford Quarry
7.
Noise
7.1
Introduction
7.1.1
Scope
This chapter assesses the noise impact of the proposed development at Brayford Quarry.
The work covered in this assessment of noise impacts produced by the site operations
includes:
•
a review of relevant guidance, existing consents and permits;
•
a review of the previous noise assessment undertaken by ARC in 1998;
•
long-term unattended baseline monitoring at four sensitive receptors, plus shortterm attended monitoring of on site noise sources for prediction assessment;
•
production of noise models based upon the proposed development plan;
•
reporting of the findings for sensitive receptors based upon the requirements of
MPS 2 etc; and
•
advice on any appropriate amelioration measures to reduce noise by applying best
practice means where required.
The objectives of the assessment are to:
•
determine the current baseline noise levels at selected sensitive receptors and
whether the quarry is contributing significantly to the baseline noise levels; and
•
determine if the noise levels due to site activities for the proposed operation will
exceed the threshold in relevant guidance, existing consents and permits.
A brief summary of noise theory and terminology used within this report is given in
Appendix A7.1.
7.2
Assessment Methodology
7.2.1
Minerals Policy Statement 2 (MPS 2): (2005)
The guidance note Mineral Policy Statement 2 (MPS 2) [ 1]sets out the current government
policies that should be followed with regard to noise arising from surface mineral workings
and associated waste operations.
[1] Office of the Deputy Prime Minister: London (2005), Minerals Policy Statement 2: Controlling and Mitigating the
Environmental Effects of Minerals Extraction in England, ISBN 1 85112 780 1.
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MPS 2 presents a variable limit at noise sensitive properties during normal operational
daytime hours of between 0700 to 1900 hrs that does not exceed the background level by
more than 10 dB(A), subject to a maximum nominal free-field limit of 55 dB LAeq,1h.
However, it is recognised within the guidance document that a limit of 10 dB(A) above
background in quiet rural areas will under many circumstances be difficult to achieve. It is
further stated that:
“In such cases, the limit set should be as near that level as practicable during normal
working hours (0700 to 1900 hrs) and should not exceed 55 dB LAeq,1hr free field.”
With regard to night-time operations it is stated that limits should not exceed 42 dB LAeq,1hr
(free-field) at noise sensitive dwellings.
A level of 70 dB LAeq,1h (free field) is further suggested for periods of up to 8 weeks in a year
to facilitate noisier temporary operations. Examples of this would be the construction of
baffle mounds, soils stripping, removal of spoil heaps and the construction of new
permanent land forms which would merit a temporary raised limit. It also leaves Mineral
Planning Authorities and mineral operators the ability to negotiate trade-offs between
shorter periods of time versus higher noise limits and vice versa.
Within MPS 2, sensitive receptors are detailed as including:
“dwellings, gardens, places of worship, educational establishments, hospitals or similar
institutions, livestock farms, some factories or any other property likely to be adversely
affected by an increase in noise levels.”
7.2.2
World Health Organisation (WHO) Guidelines for Community Noise (1999) [2]
The suggested noise limits in MPS 2 closely relate to World Health Organisation (WHO)
guidelines on outdoor ambient daytime noise levels to prevent moderate or serious
annoyance and outdoor night time levels to prevent sleep disturbance to residents sleeping
with windows partially open. A summary of WHO noise level guidelines relevant to this
report are given in Table 7.2.1.
Table 7.2Table 7.2.1: WHO Outdoor Noise Level Guidelines
2
[ ]Guidelines for Community Noise, 1999. World Health Organisation
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Effect
7.2.3
LAeq dB (free field)
Time Period
LAmax,fast dB
Daytime - Moderate annoyance
50 (free field)
16 hours
-
Daytime - Serious annoyance
55 (free field)
16 hours
-
Night time - Sleep Disturbance
45 (facade)
8 hours
60
Noise Limits Defined in the Planning Permission (1999) [ 3]
Noise limits have been specified in the existing Bray Valley planning permission
(02/14/25237/98) for all operations for the life of the site, as follows:
E
Daytime noise levels arising from the site shall not exceed 50 dB LAeq,1hr free-field
between the hours 0700 to 1900 Monday to Friday, and 0700 to 1300 hours on
Saturdays.
E
Night-time noise levels shall not exceed 43 dB LAeq,1hr free-field between 0400 and
0700 hours Monday to Saturday.
The permission presently governs all site operations including both the existing process
plant and quarry operations e.g. soil stripping, excavations and loading. The development
proposed for this application relates to only the plant site operations.
7.3
Review of Noise Impact Assessment Report 1998
7.3.1
General
A noise impact assessment [ 4] was conducted, by ARC Ltd in 1998 for the submission of
the consolidating planning permission Ref: 02/14/25237/98.
Noise levels were measured at five noise sensitive receptors. The location of the receptors
in relation to the site are shown in Figure B1 in Appendix B.
7.3.2
Noise Criteria
The 1998 assessment used noise criteria given in Mineral Planning Guidance 11 [ 5], of
55 dB LAeq,1hr (free field) limit, and 70 dB LAeq,1hr (free field) during temporary operations.
[3]County of Devon (1999), Grant of Conditional Planning Permission, Application No. 02/14/25237/98.
4
[ ] T. Hill (1998), Bray Valley Quarries, Brayford Consolidating Application – Noise Impact Assessment.
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7.3.3
Results
Background noise levels, predicted LAeq noise levels and maximum LAeq noise levels during
temporary works of the 1998 noise impact assessment at the noise sensitive receptors are
shown in Tables 7.3.1 to 7.3.3 below.
Table 7.3.1: Background Noise Levels Measured During 1998 Assessment
Receptor
Background Noise Level (No Units - Assumed to be LA90,1hr (dB))
Newtown
37
Charles
37
Welcombe
38
Higher Shutscombe
37*
High Bray
37
Note: *Assumed level based upon the results from the other Receptors
5
[ ] Department for Communities and Local Government (1993), Minerals Planning Guidance 11: The control of noise at surface mineral
workings, ISBN: 0 11 752779 3.
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Table 7.3.2: Predicted Noise Levels 1998 Assessment
Receptor
Worst Case
Typical Maximum
5 Yr
15 Yr
30 Yr
45 Yr
50 Yr
5 Yr
15 Yr
30 Yr
45 Yr
50 Yr
47
49
-
-
-
42
43
-
-
-
49
49
48
48
-
43
46
45
44
-
49
51
53
48
48
47
48
49
46
46
44
44
45
45
45
42
42
43
43
43
45
45
46
45
45
44
44
44
43
43
Newtown
Charles
Welcombe
Higher
Shutscombe
High Bray
Note: Noise levels are 1 hour Free Field LAeq
Table 7.3.3: Noise Levels during Temporary Works
Receptor
Maximum Noise Level (Assumed to be LAeq,1hr (dB))
Newtown
50
Charles
62
Welcombe
54
Higher Shutscombe
62
High Bray
62
It was stated that “for the majority of the time, quarrying activities will be at distances
greater than those used in the predictions for the nearest properties. Again, this will have
the additional effect of reducing noise levels further at noise sensitive properties.”
7.3.4
Conclusions
The 1998 noise impact report concluded that “the anticipated noise levels at all noise
sensitive properties will comply with the standard limits of 55 dB LAeq,1hr free field, contained
within MPG 11”.
“The limit of 70 dB LAeq,1hr free field will not be exceeded during temporary operations such
as bund construction and overburden removal, placement and storage.”
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7.4
Baseline Noise Monitoring
7.4.1
General
Unmanned long-term baseline noise monitoring was carried out continuously from 15th
August 2007 to 21st August 2007. Noise meters were installed at four of the five receptors
previously identified in the 1998 Noise Impact Assessment.
The locations at which the monitoring was undertaken are shown in Figure B2, Appendix
A7.2.
Photographs of the monitoring receptors are illustrated in Appendix A7.3.
7.4.2
Instrumentation
Noise monitoring was undertaken using Brüel and Kjær 2238, Type 1 integrating sound
level meters. Serial numbers of the equipment are shown in Tables D1 in Appendix D.
The procedures for monitoring conformed to BS 7445: 1991 Description and Measurement
of Environmental Noise [ 6]. The instrumentation were protected by all-weather kits at all
times, including a microphone windshield. The sound level meters were set to measure
various noise parameters including the LAeq and LA90 values logging at 15 minute
contiguous intervals. Each instrument was calibrated immediately before and after the
survey period - no significant changes (±1 dB) were noted.
Calibration certificates for the noise instrumentation are available on request.
7.4.3
Meteorological Conditions
Weather conditions throughout the monitoring period were within the limits specified in
BS 7445.
Weather conditions during both site visits (15/08/07 and 21/08/07) were noted as dry with
sunny spells. On the 15/08/07 the average daytime temperatures were 17°C, with a southwesterly wind up to 1 ms-1.
6
[ ] British Standard BS 7445 1991 ‘Description and Measurement of Environmental Noise’, British Standards Institution
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The weather reports are shown in Appendix A7.4. It should be noted that heavy rainfall is
shown on Saturday 18/08/07.
7.4.4
Results
A summary of the measured baseline noise levels is given in Table 7.4.1 based on the
existing approved operating hours of weekday 0700-1900 hours, Saturday 0700-1300
hours, and night-time 0400-0700 hours. The results for receptors 1 to 4 are shown in
graphical form in Appendix F.
Receptor
No.
1
2
3
4
Description
Charles Church
Welcombe Farm
Higher
Shutscombe Farm
Braytown Farm
Average
Daytime Level
(dB)
Average
Night-time
Level (dB)
LAeq
LAeq
Thursday 16/08/07
56
38
Friday 17/08/07
48
35
Saturday 18/08/07
48#
42#
Monday 20/08/07
50
38
Thursday 16/08/07
47
40
Friday 17/08/07
53
43
Saturday 18/08/07
46#
41#
Monday 20/08/07
49
40
Thursday 16/08/07
49
42
Friday 17/08/07
53
36
Saturday 18/08/07
52#
38#
Monday 20/08/07
52
40
Thursday 16/08/07
58
41
Friday 17/08/07
56*
37
Saturday 18/08/07
47#
42#
Monday 20/08/07
48
35
Date/Time
Table 7.4.1: Baseline Monitoring Results
Note:
* Occupier states lawn mowed in afternoon
Heavy rainfall during measurement period
#
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7.4.5
Discussion of Results
The noise climate in the vicinity of the receptors and quarry comprises of local traffic noise
(the volume of which varies depending on the receptor location), aircraft noise from the
local RAF base, farm animals and bird song. Heavy rainfall occurred on Saturday 18/08/07
as shown in Appendix E. Noise from the quarry works was not audible at any selected
sensitive receptor during installation and collection of the noise measurement equipment.
Average daytime noise levels ranged from 46 dB LAeq,1hr to 58 dB LAeq,1hr. These are typical
overall daytime levels for a rural area. The most recent National Noise Incidence survey [ 7]
found that 54% of the population of the UK live in dwellings exposed to daytime (07:0023:00) noise levels above 55 dB LAeq.
It has been confirmed by the Site manager [ 8] that the quarry was operating normally during
the time of the ambient monitoring. There was no change in operation of the plant with the
exception of the primary crusher being mounted in a slightly elevated position.
There is no reason to assume that monitored noise levels at selected sensitive receptors
are elevated due to existing quarrying operations.
7.5
Measurement of Operational Noise at the Quarry
7.5.1
General
Measurement of operational noise at the quarry site was carried out on Thursday 16th
August 2007.
A number of plant measurements were undertaken, primarily of mobile plant including
wheeled loaders, dumpers, diggers etc.
Sound pressure level measurements were recorded for each of the activities, both while the
mobile plant was stationary and when operating at maximum capacity.
[7] BRE. The National Noise Incidence Study 2000/2001. Volume 1 – Noise Levels.
8
[ ] Details from site manager – Paul Owsianka, 18/09/07
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Noise measurements of each item of plant were taken with all the plant switched off to
ensure the specific measurements were not biased or corrupted, and to allow a more
accurate prediction of LWA from specific plant.
7.5.2
Instrumentation
Noise measurements of specific plant were undertaken using a NorSonic 118 real time
sound analyser.
The equipment was set to measure the LAeq, LA90 and frequency spectrum values logging at
contiguous periods of one second for all measurements. The equipment was calibrated
prior to, and checked after the monitoring periods – no significant changes (±1 dB) were
noted.
The serial number for the measuring equipment used is given in Table D2, Appendix D.
The calibration certificate for the noise instrumentation is available on request.
7.5.3
Meteorological Conditions
Weather conditions during the specific measurements carried out on Thursday 16th August
2007 were dry, average temperature of around 17°C, with no discernible wind.
7.5.4
Specific Noise Measurement Results
Noise levels for the various operations within the Site were obtained from a variety of
sources. Where possible, noise data was collated by direct measurement of the same or
similar activities, including:
•
Brayford quarry mobile plant that will also be used in the operation of the
replacement plant;
•
data supplied by Hanson for the drystone plant, previously operating at Hanson’s
Trusham quarry;
•
data obtained by direct measurement of a similar Benninghoven coated roadstone
plant operated by Hanson at Pottal Pool quarry, Staffordshire, surveyed by Scott
Wilson in October 2007.
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The measured operational noise levels have been used to calculate the sound power levels
of the plant and machinery used on-site.
The sound power, LWA was determined by monitoring the sound pressure, Lp at known
distances from the plant, and the following equation:
LWA = L p + 20 log r + 8
Where: r = the distance from source to measurement position in metres.
From the measured data, the Sound Power Level (LWA) of each activity was calculated and
is summarised in Table 7.5.1.
Table 7.5.1: Calculated Worst Case Sound Power Level (LWA) of Mobile Plant
Activity
Sound Power Level (LWA) (dB)
JCB Groundhog Buggy
94
Wheeled Loader - Komatsu WA500
101
Dump truck - Komatsu HM400
104
Dump truck - Volvo A40D
100
Dump truck - Volvo A25C
99
Tractor - Jon Deere 4055
99
Forklift - Maniscopic Maniton MT1235CP
102
Mini digger ZAXIS 30
92
Wheeled Loader - Volvo BM
103
Primary Crusher
114
Digger - Hitachi ZAXIS 650
104
Noise data for the fixed plant to be used in the proposed development is summarised in
Table 7.5.2.
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Table 7.5.2: Sound Power Level (LWA) of Fixed Plant
Activity
Source
Feed Hopper
-
Stone Crush Plants (Secondary) Trusham Screen House
Upper level
Lower level
Selection screen house and final
Semi mobile screen
screen grading section
Plant (internal)
Asphalt Plant
LWA (dB) Reference
Defra Report. Table 1(a),
113
ref no. 12.
Scott Wilson Previous
105
Measurement Data
94
Supplied Information
92
109
92**
Dryer (external)
103
Burner (external)
102
Hopper below mixer
87
Overflow collection hopper
Trusham lorry out station
Conveyor motor
Conveyor belt
Wheeled loader loading
Supplied Information
Defra Report. Table 1(b),
ref no. 14.
Measured sound pressure
Supplied Information
113++
89
Supplied Information
96
Supplied information
**
Apply 15 dB cladding reduction which was validated by comparing the measured internal
and external sound pressure level;
++
Apply 50 % ontime according to the advice from the site manager, stating that the overflow
does not happen often;
7.6
Prediction Methodology
7.6.1
Introduction
The prediction of noise levels at sensitive receptors has been performed according to the
method in ISO 9613 Part 2.
7.6.2
Selected Sensitive Receptors
A number of noise sensitive receptors have been identified in all directions from the site and
the approximate distances between these and the new asphalt plant at Brayford are listed in
Table 7.6.1.
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Table 7.6.1: Selected Sensitive Receptors and Distances to Asphalt Plant
Receptor
7.7
Distance Between Asphalt Plant and Receiver (metres)
Charles Church
685
Welcombe Farm
400
Higher Shutscombe Farm
800
Braytown Farm
785
Assumptions and Parameters
The assumptions and parameters used in the model are all based on the best information
available, and are detailed in Appendix A7.7.
7.7.1
Predicted Noise Levels
Two scenarios were considered in the noise model:
•
Scenario 1: predicting the noise level of the proposed development with all
production plant operational (including the mobile primary crusher in Gards Pit); and
•
Scenario 2: predicting the noise level of the proposed development with all plant
operational except the mobile primary crusher.
Table 7.6.2 presents the predicted noise levels from the noise models described above for
each identified sensitive receptor location.
For each receptor noise levels have been
calculated at two heights, typical of ground floor and first floor window level.
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Receptor
No.
Description
1
Charles Church
2
Welcombe Farm
3
Higher Shutscombe
Farm
4
Braytown Farm
Floor Level
Scenario 1 Noise
Level LAeq (dB)
Scenario 2 Noise
Level LAeq (dB)
Ground Floor
32
26
First Floor
32
27
Ground Floor
42
42
First Floor
42
42
Ground Floor
28
27
First Floor
28
28
Ground Floor
39
38
First Floor
41
41
Table 7.6.2: Predicted Noise Levels LAeq,1hr from the Noise Modelling
The results in Table 7.6.2 show that during the daytime, for both scenarios at all receptors
noise levels are predicted to be below the 50 dB LAeq,1hr limit defined in planning permission
ref no: 02/14/25237/98.
During the night-time, for both scenarios, all receptors are
predicted to be within the 43 dB LAeq,1hr limit specified in the planning permission. Assuming
that the noise levels from any other site activities (not included in this assessment e.g. soils
stripping, mineral extraction) are at or above the 50 dB(A) limit, the worst case predicted
noise level of 42 dB(A) from operations within this application area would not result in any
breach of the existing permitted day time level, i.e. 50 dB.
This suggests that the predominant noise source at the receptors is not site operations at
the quarry, which confirms the 1998 noise impact report which concluded that “the
anticipated noise levels at all noise sensitive properties will comply with the standard limits
of 55 dB LAeq,1hr free field, contained within MPG 11”.
The predicted noise levels at all the selected noise sensitive receptors are well within the
daytime standard limit of 55 dB LAeq,1h contained within MPS 2, this also complies with the
limits in the World Health Organisation (WHO) Guidelines for Community Noise.
The
predicted noise level during the night-time does not exceed the limit of 42 dB LAeq,1hr at all
receptors.
Noise contour plots of the predictions are shown in Appendix A7.8.
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7.8
Mitigation
7.8.1
Mitigation Measures
It is expected that the quarry operator will follow best practicable means to reduce the noise
impact upon the local community including the following: The following operational noise
mitigation measures are suggested:
•
mobile plant items are often fitted with reversing alarms, as a safety feature, where
the driver’s visibility is restricted.
Noise from vehicles with standard “bleeper”
reversing alarms may give rise to complaint and are known to be a source of noise
at this site. To reduce the likelihood of noise complaint from site mobile plant,
alternative reversing alarms and/or alarms fitted with background noise sensing
devices should be considered. The use of white noise reversing alarms such as the
BBS-82 manufactured by Brigade can considerably reduce their noise impact.
Background noise sensing alarms work by adjusting the level of the alarm to be
audible above the background noise level, without being unnecessarily loud.
Another type of reversing alarm sounds only when the sensors detect persons in the
vicinity of the vehicle;
•
regular maintenance of fixed and mobile plant, including attention to bearings,
exhausts and silencers will be undertaken to ensure noise levels do not increase
over time. All conveyor joints will vulcanised rather than clipped.
Particular
attenuation should be made to maintenance of conveyors, to ensure that roller
bearings, drive motors, discontinuities in the belts (such as repair joints) etc
becomes a source of noise; and
•
it is recommended that the facility adopts a stringent noise management policy
designed to ensure the noise levels at nearby dwellings are kept to a minimum at all
times. It is recommended that the facility conducts regular meetings with one or
more elected resident’s representatives to ensure noise levels do not become
excessive. The facility should have make available and publicise a 24hr contact
telephone number for surrounding receptors, should noise levels become
excessive.
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7.9
Discussion
During site visits in August 2007, it was identified that the noise climate in the vicinity of the
receptors and quarry comprises of local traffic noise (the volume of which varies depending
on the receptor location), aircraft noise from military aircraft, farm animals and bird song.
Noise from the quarry works was not audible at any of the sensitive receptors.
As discussed above current activities at the quarry were not audible at any of the receptors
during the installation and collection of the measurement equipment. It has been confirmed
by the Site manager that the quarry was operating normally during the time of the ambient
monitoring. Therefore, it is unlikely that the current quarrying activities are contributing
significantly to the noise climate and are deemed to be acceptable.
The noise levels at the selected receptors due to the proposed development have been
predicted based on measured data of existing plant and supplied data of new plant using
the ISO 9613-2 methodology. The predicted daytime noise levels are all below the 50 dB
LAeq,1hr limit specified in the existing planning permission. This further suggests that the
predominant noise source at the receptors is not operations at the quarry. The predicted
LAeq,1hr at all receptors during the night-time were found to be within the 43 dB LAeq,1hr limit
specified within the existing planning permission.
Predicted noise levels due to the proposed changes to activities at the quarry indicate that
both the planning permission noise limits are unlikely to be exceeded.
7.10
Conclusions
Long-term noise monitoring at selected sensitive receptors have been undertaken.
Based on site observations and the noise modelling of quarry activities there is no reason
to assume that monitored noise levels at selected sensitive receptors are elevated due to
existing quarrying operations.
The predicted daytime noise levels from proposed operations are all below the 50 dB
LAeq,1hr limit specified in the existing planning permission.
The predicted LAeq,1hr at all
receptors during the night-time were found to be within the 43 dB LAeq,1hr limit specified
within the existing planning permission.
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Appendix A7.1: Noise Terminology And Perception
Between the quietest audible sound and the loudest tolerable sound there is a million to
one ratio in sound pressure (measured in Pascals, Pa). Because of this wide range, a noise
level scale based on logarithms is used in noise measurement called the decibel (dB)
scale. Audibility of sound covers a range of approximately 0 to 140 dB. The human ear
system does not respond uniformly to sound across the detectable frequency range and
consequently instrumentation used to measure noise is weighted to represent the
performance of the ear. This is known as the 'A weighting' and annotated as dB(A). Table
A1 lists the sound pressure level in dB(A) for common situations.
Table A1: Noise Levels for Common Situations
Approximate Sound Pressure Levels (dB(A))
Example
0
Threshold of hearing
30
Rural area at night
50
Quiet office, no machinery
80
General factory noise level
100
Pneumatic drill
140
Threshold of pain
The noise level at a measurement point is rarely steady, even in rural areas, and varies
over a range dependent upon the effects of local noise sources. Close to a busy motorway,
the noise level may vary over a range of 5 dB(A), whereas in a suburban area this variation
may be up to 40 dB(A) and more due to the multitude of noise sources in such areas (cars,
dogs, aircraft etc.) and their variable operation. Furthermore, the range of night-time noise
levels will often be smaller and the levels significantly reduced compared to daytime levels.
When considering environmental noise, it is necessary to consider how to quantify the
existing noise (the ambient noise) to account for these second to second variations.
A parameter that is widely accepted as reflecting human perception of the ambient noise is
the background noise level, LA90. This is the noise level exceeded for 90 % of the
measurement period and generally reflects the noise level in the lulls between individual
noise events. Over a one hour period, the LA90 will be the noise level exceeded for 54
minutes.
The equivalent continuous A-weighted sound pressure level, LAeq is the single number that
represents the total sound energy measured over that period. LAeq is the sound level of a
notionally steady sound having the same energy as a fluctuating sound over a specified
measurement period. It is commonly used to express the energy level from individual
sources that vary in level over their operational cycle.
Human subjects, under laboratory conditions, are generally only capable of noticing
changes in steady levels of no less than 3 dB(A). It is generally accepted that a change of
10 dB(A) in an overall, steady noise level is perceived to the human ear as a doubling (or
halving) of the noise level. (These findings do not necessarily apply to transient or nonReplacement Process Plant
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steady noise sources such as changes in noise due to changes in road traffic flow, or
intermittent noise sources).
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Appendix A7.2: Location Maps
Figure B1: Noise Sensitive Properties Defined in the Noise Impact Assessment 1998
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Figure B2: Receptor Locations in the Current Noise Assessment
Receptor 4
Receptor 3
Receptor 2
Receptor 1
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Appendix A7.3: Baseline Noise Monitoring Photographs
Figure C1: Long-term Baseline Noise Monitoring at the Charles Church (Receptor 1)
Figure C2: Long-term Baseline Noise Monitoring at Welcombe Farm (Receptor 2)
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Figure C3: Long-term Baseline Noise Monitoring at Higher Shutscombe Farm (Receptor 3)
Figure C4: Long-term Baseline Noise Monitoring at Braytown Farm, High Bray (Receptor 4)
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Appendix A7.4: Instrumentation
Table D1: Instrumentation for Long-term Baseline Noise Monitoring
Meter Serial Number
Microphone Serial
Number
Brüel and Kjær 2238 Type 1 Sound Level Meter
2562627
2555265
Brüel and Kjær 2238 Type 1 Sound Level Meter
2562671
2555536
Brüel and Kjær 2238 Type 1 Sound Level Meter
2381585
2379764
Brüel and Kjær 2238 Type 1 Sound Level Meter
2201511
2200371
Meter Type
Table D2: Instrumentation for Specific Plant Noise Measurements (at the Quarry Site)
Meter Type
NorSonic 118 Real Time Sound Analyser
Replacement Process Plant
Planning Application
October 2007
Meter Serial Number
31441
Microphone Serial
Number
52279
100
Hanson Aggregates
Brayford Quarry
Appendix A7.5: Weather Conditions
Figure E1: Weather Condition during the Long-term Baseline Monitoring (www.metcheck.com)
Replacement Process Plant
Planning Application
October 2007
101
Hanson Aggregates
Brayford Quarry
Appendix A7.6: Baseline Noise Monitoring Results
80
70
Sound Pressure Level, Lp dB(A)
60
50
LAeq,15mins
40
LAF90,15mins
30
20
Wednesday
15/08/07
Thursday
16/08/07
Friday
17/08/07
Saturday
18/08/07
Sunday
19/08/07
Monday
20/08/07
Tuesday
21/08/07
10
Figure F1: Noise Levels at Charles Church (Receptor 1)
Replacement Process Plant
Planning Application
October 2007
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
12
:0
0
18
:0
0
0
Time
102
Hanson Aggregates
Brayford Quarry
80
70
Sound Pressure Level, Lp dB(A)
60
50
LAeq,15mins
LAF90,15mins
40
30
20
Wednesday
15/08/07
Thursday
16/08/07
Friday
17/08/07
Saturday
18/08/07
Sunday
19/08/07
Monday
20/08/07
Tuesday
21/08/07
10
Replacement Process Plant
Planning Application
October 2007
0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
Figure F2: Noise Levels at Welcombe Farm (Receptor 2)
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
0
18
:0
0
12
:0
0
06
:0
0
00
:0
18
:0
12
:0
0
0
Time
103
Hanson Aggregates
Brayford Quarry
80
70
Sound Pressure Level, Lp dB(A)
60
50
LAeq,15mins
40
LAF90,15mins
30
20
10
Wednesda
y
15/08/07
Thursday
16/08/07
Friday
17/08/07
Saturday
18/08/07
Sunday
19/08/07
Monday
20/08/07
Tuesday
21/08/07
12
:0
0
18
:0
0
00
:0
0
06
:0
0
12
:0
0
18
:0
0
00
:0
0
06
:0
0
12
:0
0
18
:0
0
00
:0
0
06
:0
0
12
:0
0
18
:0
0
00
:0
0
06
:0
0
12
:0
0
18
:0
0
00
:0
0
06
:0
0
12
:0
0
18
:0
0
00
:0
0
06
:0
0
12
:0
0
18
:0
0
0
Tim e
Figure F3: Noise Levels at Higher Shutscombe Farm (Receptor 3)
Replacement Process Plant
Planning Application
October 2007
104
Hanson Aggregates
Brayford Quarry
80
70
Sound Pressure Level, Lp dB(A)
60
50
LAeq,15mins
40
LAF90,15mins
30
Figure F4: Noise
Levels at Braytown Farm
20
Wednesday
15/08/07
Thursday
16/08/07
Friday
17/08/07
Saturday
18/08/07
Sunday
19/08/07
Monday
20/08/07
Tuesday
21/08/07
10
:0
0
:0
0
18
:0
0
12
:0
0
06
00
:0
0
18
:0
0
12
:0
0
06
:0
0
:0
0
00
:0
0
18
12
:0
0
06
:0
0
00
:0
0
18
:0
0
:0
0
12
:0
0
06
:0
0
00
18
:0
0
12
:0
0
06
:0
0
:0
0
00
:0
0
18
:0
0
12
06
:0
0
00
:0
0
18
12
:0
0
0
Time
Replacement Process Plant
Planning Application
October 2007
105
Hanson Aggregates
Brayford Quarry
Appendix A7.7: Noise Modelling Assumptions
Two scenarios were considered in the noise model to predict the noise level at residential
receptors:
•
Scenario 1:
predicting the noise level of the proposed development with all plant
operational; and
•
Scenario 2:
predicting the noise level of the proposed development with all plant
operational except the mobile crusher.
The model has been generated using CadnaA noise mapping software, version 3.6. This
implements the noise propagation calculation method identified in ISO 9613 Part 2. The noise
mapping software has been used to create noise contour plots and to investigate free field
receptor noise levels at residential properties.
Acoustic data used in the model were obtained from the existing quarry during site visit on 16th
August 2007.
• Ground contours taken from:
• Hans.bray.PF10finallayout.dxf; and
• Partly
digitised
ground
contours
OS_1_50000_Scale_colour_rasta_43686_55173
from
the
rasta
map:
• Noise mapping settings are described as follows:• Ground absorption is set to G = 1 (soft ground) except the quarry area where ground is
assumed to be reflective (G = 0) .
• Default building heights = 6 m
Replacement Process Plant
Planning Application
October 2007
106
Hanson Aggregates
Brayford Quarry
Appendix A7.8: Noise Model Contour Plots
Replacement Process Plant
Planning Application
October 2007
107