Noise Assessment
Proposed Extension to
Asphalt Plant
Operating Hours at
Halkyn Quarry, Flintshire
CEMEX UK OPERATIONS
R21.11022/3/AP
Date of Report: 19 May 2021
Noise Assessment – Proposed Extension to Asphalt Plant Operating Hours at
Halkyn Quarry, Flintshire
19 May 2021
Vibrock Limited Shanakiel
Ilkeston Road, Heanor
Derbyshire, DE75 7DR
Tel: +44 (0) 1773 711211
Fax: +44 (0) 1773 711311
Email: [email protected]
Web: www.vibrock.com Report No. R21.11022/3/AP
REPORT DETAILS
Client Cemex UK Operations
Report Title Noise Assessment – Proposed Extension to Asphalt Plant Operating Hours
Site Address Halkyn Quarry, Pant-y-Pwll Dwr, Pentre Halkyn, Flintshire
Report Ref. R21.11022/3/AP
Vibrock Contact [email protected]
QUALITY ASSURANCE
Issue
No. Issue Date Author Technical Review
1 09/03/21
A Pickford MIOA
Director
R Kennedy MIOA
Director
2 11/03/21 A Pickford MIOA
Director
R Kennedy MIOA
Director
3 19/05/21 A Pickford MIOA
Director
R Kennedy MIOA
Director
This report has been prepared by Vibrock the trading name of Vibrock Limited, with all reasonable skill, care
and diligence within the terms of the Contract with the client, incorporating our General Terms and Conditions
of Business and taking account of the resources devoted to it by agreement with the client.
We disclaim any responsibility to the client and others in respect of any matters outside the scope of the above.
This report is confidential to the client and we accept no responsibility of whatsoever nature to third parties to
whom this report, or any part thereof, is made known. Any such party relies on the report at their own risk.
Noise Assessment – Proposed Extension to Asphalt Plant Operating Hours at
Halkyn Quarry, Flintshire
19 May 2021
Report No. R21.11022/3/AP
CONTENTS
1.0 Introduction 1
2.0 Noise Policy and Guidance 2
3.0 Background Noise Survey 4
4.0 Site Noise Level Predictions 6
5.0 Assessment 8
6.0 Recommendations 9
7.0 Summary 10
8.0 References 11
FIGURE 1 Location Plan
TABLE 1 Noise Source Details - List of Plant, On-time Assumptions
and Associated Sound Power Levels
APPENDIX 1 Acoustic Terminology
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Page 1
1.0 INTRODUCTION
1.1 Overview
1.1.1 Vibrock Limited were commissioned to undertake a noise assessment to accompany a
planning application to vary a condition to extend the operating hours of the asphalt
plant at Halkyn Quarry in Flintshire.
1.1.2 Further explanation of the acoustic terminology used within this report is provided in
Appendix 1.
1.2 Planning Conditions (Application ref: 056419/059487)
1.2.1 The extant planning conditions relevant to this assessment are as follows:
Condition 4 - Except in emergencies to maintain safe quarry working (which shall be
notified to the Mineral Planning Authority as soon as practical), or with the prior
agreement of the Mineral Planning Authority, the hours of operation of the approved
replacement asphalt plant shall be:-
a) 0600 hours to 1800 hours on Monday to Friday
0600 hours to 1200 hours on Saturdays
b) No HGVs shall enter the site until 0615 Monday to Saturday
No HGVs shall enter or leave the site on Sundays or Public Holidays
c) No operations, apart from environmental monitoring, servicing, maintenance
and testing of static and mobile plant, or emergency works in connection with
the safety of the Site, shall be carried out outside these hours or on Sundays or
Public Holidays without the prior written agreement of the Mineral Planning
Authority.
Condition 7 - Between the hours of 0600 and 0700 the noise level from the site measured
at nearest noise sensitive properties used as dwellings shall not exceed 42 dB LAeq, 1h
and between 0700 and 1800 hours the noise level from the site measured at nearest
noise sensitive properties used as dwellings shall not exceed 10dB LAeq (1 hour) above
background noise levels.
1.3 Proposals
1.3.1 The application seeks to vary Condition 4 (Hours of Operation) of permission reference
059487 to allow for the operation of the Asphalt Plant (permitted under planning
permission 056419) and associated vehicle movements outside of permitted hours on
28 occasions per year. It is proposed that vehicles travelling to and from the site will
pass through the village of Pentre Halkyn on route to the A55 as per the current
situation.
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2.0 NOISE POLICY AND GUIDANCE
2.1 Planning Policy Wales (PPW)
2.1.1 Planning Policy Wales sets out the land use planning policies of the Welsh Government.
It is supplemented by a series of Technical Advice Notes (TANs), Welsh Government
Circulars, and policy clarification letters, which together with PPW provide the national
planning policy framework for Wales.
2.1.2 The primary objective of PPW is to ensure that the planning system contributes towards
the delivery of sustainable development and improves the social, economic,
environmental and cultural well-being of Wales.
Minerals
2.1.3 The role of the planning authority in relation to mineral extraction is to balance the
fundamental requirement to ensure the adequate supply of minerals with the
protection of amenity and the environment. The key principles are to:
• provide positively for the safeguarding and working of mineral resources to
meet society’s needs now and in the future, encouraging the efficient and
appropriate use of high quality materials;
• protect environmental and cultural characteristic of places, including those
highly cherished for their intrinsic qualities, such as wildlife, landscapes,
ancient woodlands and historic features, and to protect human health and
safety and general well-being;
• reduce the impact of mineral extraction and related operations during the
period of working by ensuring that impacts on relevant environmental
qualities caused by mineral extraction and transportation, for example air
quality and soundscape, are within acceptable limits; and
• achieving, without compromise, a high standard of restoration and
aftercare so as to avoid dereliction and to bring discernible benefits to
communities, heritage and/or wildlife, including beneficial after uses or
opportunities for enhancement of biodiversity and the historic
environment.
Noise
2.1.4 Mineral workings should not cause unacceptable adverse environmental or amenity
impact. Where this is not possible working needs to be carefully controlled and
monitored so that any adverse effects on local communities and the environment are
mitigated to acceptable limits. Any effects on local communities and the environment
must be minimised to an acceptable standard.
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2.2 Minerals Planning Guidance Note 11: The Control of Noise at Surface Mineral
Workings
2.2.1 This guidance, published in April 1993, provides advice to mineral planning authorities
and the industry on how the environmental performance of the industry can be
improved by the control of noise from operations.
2.2.2 The advice contained within this document regarding the monitoring and assessment of
noise levels is still largely applicable, however, paragraphs 31 to 42 have been
superseded by Mineral Technical Advice Note 1.
2.3 Minerals Technical Advice Note (Wales) 1: Aggregates
2.3.1 This guidance sets out detailed advice on the mechanisms for delivering policy for
aggregates extraction by mineral planning authorities and the aggregates industry.
2.3.2 In terms of noise, the guidance states that where aggregates extraction and related
operations occur close to areas that are sensitive to noise, particularly residential areas,
noise impact must be minimised to acceptable levels.
2.3.3 Mineral planning authorities should have regard to the background noise levels and the
threshold at which significant effects are likely at noise sensitive properties when
considering the acceptability of proposals or setting noise limits in a planning condition.
2.3.4 In relation to noise limits, MTAN1 offers the following specific advice.
“Noise limits should relate to the background noise levels (LA90,T), subject to a
maximum daytime noise limit of 55 dB(A) where background noise levels exceed
45 dB(A). 55 dB(A) is the lower limit of the daytime noise levels where serious
annoyance is caused.
Where background noise is less than 45 dB(A), noise limits should be defined as
background noise levels plus 10 dB(A).
Night-time working limits should not exceed 42 dB(A) at noise sensitive
properties.
Daytime working is defined as 07:00 – 19:00 hours and night-time as
19:00 – 07:00 hours.
Noise limits should be set in terms of LAeq,T over a 1-hour measuring period. LAeq, is
the noise index used to describe the "average" level of noise that varies with time
(T) and should be measured "free-field" that is, at least 3.5m away from a façade
to prevent reflection of noise by any façade that faces the noise source.
During temporary and short-term operations higher levels may be reasonable but
should not exceed 67dB(A) for periods of up to 8 weeks in a year at specified noise
sensitive properties.”
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3.0 BACKGROUND NOISE SURVEY
3.1 Survey Methodology
3.1.1 Noise monitoring was conducted during a 3 – 4 day period from Saturday
27 February 2021 to Tuesday 2 March 2021 at a location selected to represent the
acoustic environment at the nearest residential dwelling to the existing asphalt plant
site.
3.1.2 A plan identifying the nearest noise-sensitive receptor and the location of the asphalt
plant within Halkyn Quarry is provided in Figure 1.
3.2 Instrumentation
3.2.1 Monitoring was undertaken using the following equipment.
Manufacturer Type Serial No.
Cirrus Class 1 Integrating Sound Level Meter CR:1710 G078470
Cirrus Acoustic Calibrator CR:515 56097
3.2.2 During all measurements the microphone was protected with an outdoor windshield.
3.2.3 The monitoring position was ‘free field’ (no vertical reflective surfaces within 3.5 metres
of the microphone) and at a height of between 1.2 – 1.5 metres above ground level.
3.2.4 The following set-up parameters were used:
• Time Weighting: Fast
• Frequency Weighting: A
• Averaging-Integrating Period: 1 hour
• Data Logging: Repeat (Contiguous)
3.2.5 With the equipment set up in the configuration used during measurement, field
calibration checks were performed on site immediately before and after the survey
period using a sound calibrator. No significant drift (i.e. no greater than ±0.5 dB) in the
calibration value was observed between the initial and final checks.
3.3 Observations
3.3.1 During the survey period weather conditions were dry with average wind speeds
considered to be less than 5 ms-1
and predominantly from a southerly direction. Cloud
cover was in the region of 0 – 50% and temperatures ranged from 3 – 11°C.
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3.3.2 The acoustic environment in the vicinity of the site is predominantly influenced by
distant road traffic using the A55 along with intermittent vehicle movements on other
local links. Other notable sound sources included livestock and birdsong.
3.4 Results
3.4.1 The data collected during the survey is presented in Table 1. A summary of the survey
results, during time periods pertinent to this assessment, is presented below.
Date Day Time Period
Representative
Background Noise Level
LA90,1h (dB)
27/02/2021 Saturday 18:00 – 19:00 40
28/02/2021 Sunday 18:00 – 19:00 40
01/03/2021 Monday 18:00 – 19:00 47
3.4.2 For the purposes of this assessment the representative background noise level is
considered to be 40 dB during the period from 6 – 7pm which is the daytime period
during which the asphalt plant is proposed to be operated.
3.4.3 During the period 7pm to 7am a fixed limit of 42 dB is applicable irrespective of the
background noise level. The 42 dB night-time limit is specified in the site’s current
planning permission and is also the limit recommended within MTAN1 which defines the
night-time period as 19:00 – 07:00 hours.
3.5 Measurement Uncertainty
3.5.1 The coronavirus pandemic has presented challenges in obtaining representative
background sound levels because typical road, air and rail transport usage have been
reduced by travel restrictions and social distancing measures. Department for Transport
statistics on the use of transport during the Covid-19 pandemic reveals that motor
vehicle usage (comprising cars, LGVs and HGVs) during the survey period from
27 February to 2 March 2021 ranged between 69 – 73% when compared to the
equivalent day in the first week of February 2020. This analysis is based on around 275
automatic traffic count sites across Great Britain.
3.5.2 Reduced traffic flows of this magnitude could result in background noise levels being
lower than usual by up to 1.5 dB at locations where the acoustic environment is
primarily influenced by traffic using the strategic road network. As a result the
measured background noise level of 40 dB should be regarded as conservative within
the context of this assessment.
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4.0 SITE NOISE LEVEL PREDICTIONS
4.1 Introduction
4.1.1 The level of noise in the local environs that arises from a site will depend on a number of
factors. The more significant of which are:
(a) the sound level output of the plant or equipment used on site;
(b) the periods of operation of the plant on site;
(c) the distance between the source noise and the receiving position;
(d) the presence of screening due to barriers;
(e) the reflection of sound;
(f) soft ground attenuation.
4.1.2 Noise levels associated with the proposed operation of the asphalt plant site during
extended operating hours have been calculated at the assessment location based on the
following methodology and assumptions.
4.2 Prediction Methodology
4.2.1 In order to assist in the calculation of predicted noise levels from the asphalt plant site,
CadnaA noise modelling software has been used. The noise prediction software has
been configured to undertake the noise calculations in accordance with Annex F of
British Standard BS 5228-1:2009+A1:2014 ‘Code of practice for noise and vibration
control on construction and open sites. Part 1: Noise’. This guidance details methods to
estimate noise from ‘open sites’ which can include quarries, waste disposal sites and
long-term construction projects.
4.2.2 Within the model, point sources have been used to represent items of fixed plant and
items of mobile plant operating in a limited area. HGV movements have been modelled
as moving point sources. Detailed topographical data has been incorporated into the
model based on recent survey information for the quarry site and 2m contours derived
from the Nextmap 5m DTM dataset for off-site areas including receptor locations. The
calculations therefore include the beneficial screening effects of the existing overburden
bunds located on the northern, north western and eastern boundary of the site.
4.2.3 The ground absorption coefficient has been estimated according to the combination of
soft and hard ground conditions present between the source and receiver position.
‘Soft’ ground is taken to refer to surfaces which are absorbent to sound, e.g. grassland,
cultivated land or plantations as opposed to ‘hard’ ground surfaces which reflect sound
such as paving, asphalt and surface water.
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4.2.4 In accordance with BS 5228 methodology, the attenuation from screening and soft
ground attenuation have not been combined (where applicable). Instead, either the
attenuation from screening and hard ground propagation, or the attenuation provided
by soft ground alone has been included in the calculation, whichever is the greater of
the two.
4.2.5 Predictions have been made to locations representing both ground floor and first floor
positions of noise-sensitive premises. Noise levels during the daytime (07:00 – 19:00)
have been predicted within private garden areas at a height of 1.5 metres above ground
level and at least 3.5 metres from any reflecting surface other than the ground. Noise
levels during the night-time (19:00 – 07:00) have been predicted at positions
representing bedroom windows with a height of 4.0 metres above ground level and
approximately 1.0 metre from the most-exposed façade position. The predictions made
by the modelling software are for ‘free-field’ sound levels to allow for an appropriate
comparison with the free-field background sound levels measured during the survey.
4.3 Noise Source Details
4.3.1 The sound levels used within this assessment are based on measurements of current
plant and activities at the existing asphalt plant site which were made by Vibrock Limited
in February 2021. A detailed acoustic survey has been undertaken to identify the
location of noise generating plant and obtain noise measurement data for input into the
noise modelling software.
4.3.2 A list of plant and activities from which the noise predictions have been made are
presented in Table 1 along with a number of assumptions regarding activity ‘on-times’
and vehicle movements. These assumptions are based on observations during the site
inspection and discussions with the operator.
4.4 Calculation Results
4.4.1 The following table summarises the results of the noise level predictions at the identified
assessment location.
Calculated Noise Level
LAeq,1hr (free-field) dB Assessment
Location Daytime
(Ground Floor Level)
Night-time
(First Floor Level)
Parry’s Mine/Bryn Golau/Firs Cottage 39.3 39.7
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5.0 ASSESSMENT
5.1 Site Noise
5.1.1 Predicted worst case noise levels from operations associated with the asphalt plant site
during the proposed extended operating hours, have been calculated at the identified
assessment location.
5.1.2 The results are presented in the table below, together with a comparative assessment
against the extant planning condition limits which reflect current planning guidance for
minerals sites (MTAN1).
Location Period
Predicted
Worst-Case
Site Noise Level
LAeq,1h free-field dB
MTAN /
Extant
Planning
Condition
Limit
Difference
between
Site Noise and
Limit
Daytime (defined by MTAN1 as 0700 - 1900)
18:00 – 19:00 39 50* -11
Night-time (defined by MTAN1 as 1900 - 0700)
Parry’s Mine
/Bryn Golau
/Firs Cottage
19:00 – 07:00 40 42 -2
* 10 dB above the background noise level measured during the survey between 1800 – 1900 hours
5.1.3 The assessment presented in the table above demonstrates that potential noise levels
from the operation of the asphalt plant during the proposed extended hours are
expected to remain within the appropriate noise limits.
5.2 Road Traffic Noise
5.2.1 It is proposed that vehicles travelling to and from the site will pass through the village of
Pentre Halkyn on route to the A55 as per the current situation. The variation application
would therefore result in HGV movements through Pentre Halkyn during the night-time
period, however, the potential impacts from noise generated on the public highway is
unlikely to be significant when considered in the context of the extended operating
hours only being proposed on 28 occasions per year.
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6.0 RECOMMENDATIONS
6.1 The following general noise control measures should be considered during the proposed
extended operation of the site, particularly during the night-time period, to demonstrate
best practice and minimise the potential impact at noise-sensitive receptor locations
within the vicinity of the site:
(a) The stated operating hours of the site should be strictly adhered to and
effectively communicated to all site staff and subcontractors;
(b) Plant and machinery should be maintained in good working order and used in
accordance with the manufacturer’s instructions. Any defective items should
not be used;
(c) Audible reversing warning systems on mobile plant and vehicles should be of a
type which, whilst ensuring that they give proper warning, have a minimum
noise impact on persons outside the site;
(d) Unnecessary horn usage and revving of engines should be avoided;
(e) Equipment should be switched off or throttled down to a minimum when not
required;
(f) Start up plant and vehicles sequentially rather than all together;
(g) Keep vehicle routes through the site clear, well maintained and free from defects
such as pot-holes. Avoid the use of speed humps where possible;
(h) Ensure that any cladding or enclosures around generating plant are regularly
inspected for defects/damage/wear-and-tear/weathering that may negatively
impact upon the sound insulation performance of the structure. Once identified
any repairs should be carried in a timely manner;
(i) Any covers, panels or enclosure doors should be kept closed when the
equipment is in use;
(j) The drop heights of materials should be minimised and, whenever practicable,
materials should be lowered rather than dropped;
(k) Operatives should be trained to employ appropriate techniques to keep site
noise to a minimum, and should be effectively supervised to ensure that best
working practice in respect of noise minimisation is followed.
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7.0 SUMMARY
7.1 Vibrock Limited were commissioned to undertake a noise assessment to accompany a
planning application to vary a condition to extend the operating hours of the asphalt
plant at Halkyn Quarry in Flintshire.
7.2 The current operating hours of the asphalt plant are from 6am to 6pm Monday to Friday
and 6am to 12pm on Saturdays. CEMEX is proposing a condition variation to allow
operations outside of these hours on 28 occasions per year.
7.3 Predicted noise levels associated with the operation of the asphalt plant during the
proposed extended hours have been calculated at the nearest existing noise sensitive
premises to the site. These predictions have been assessed against the noise limits
outlined within extant planning condition 7 and also the guidance provided by the Welsh
Assembly (MTAN 1: Aggregates).
7.4 The results of the assessment demonstrate that site noise levels at the nearest sensitive
receptors are not expected to exceed the specified noise limits. A range of best practice
measures have been recommended to minimise noise emissions from the site during the
extended hours of operation.
7.5 The overall potential noise impact of the proposed variation application is therefore
considered to be in line with national planning policy which seeks to prevent
unacceptable adverse amenity impacts and minimise any other effects on local
communities and the environment.
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8.0 REFERENCES
1. ANC Guidelines: Environmental Noise Measurement Guide. 2013
2. British Standard 4142:2014 Methods for rating and assessing industrial and commercial
sound, BSI October 2014.
3. British Standard 5228-1:2009+A1:2014 Code of practice for noise and vibration control
on construction and open sites. Part 1: Noise. British Standards Institution 2014.
4. British Standard 7445-1:2003 Description and measurement of environmental noise –
Part 1 Guide to quantities and procedures. British Standards Institution 2003.
5. Planning Policy Wales. Welsh Government. December 2018.
6. Minerals Planning Guidance 11. The Control of Noise at Surface Mineral Workings.
Department of the Environment Welsh Office. April 1993.
7. Minerals Planning Policy (Wales). Minerals Technical Advice Note (Wales) 1: Aggregates.
Welsh Assembly Government. March 2004.
8. Guidelines for Environmental Noise Impact Assessment, v1.2. Institute of Environmental
Management & Assessment. November 2014.
Noise Assessment – Proposed Extension to Asphalt Plant Operating Hours at
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FIGURE 1
Location Plan
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TABLE 1
List of Plant, On-time Assumptions and
Associated Sound Power Levels
Plant Description
Sound
Power Level
dB(A)
Assumptions Source
Dump Truck Tipping
into Stockpiles 105 25% on-time
Measurement at
existing site
Loading Shovel in Yard 102 50% on-time Measurement at
existing site
Shovel Loading Hopper 108 10% on-time Measurement at
existing site
Elevator/Screen 109 100% on-time Measurement at
existing site
Dryer/Burner 110 100% on-time Measurement at
existing site
Stack/Fan 102 100% on-time Measurement at
existing site
Load Out 106 25% on-time Measurement at
existing site
Skid Steer Loader 100 25% on-time Measurement at
existing site
Wheelwash 102 25% on-time Measurement at
existing site
HGV 101 24 movements
per hour (20 mph)
Measurement at
existing site
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APPENDIX 1
Acoustic Terminology
Acoustic Environment
Sound from all sound sources as modified by the environment.
Sound Power Level, LWA
The total amount of sound energy per unit of time generated by a particular sound source
independent of the acoustic environment that it is in. It is a logarithmic measure of the
sound power in comparison to a specified reference level.
Equivalent continuous A-weighted sound pressure level LAeq,T
Value of the A-weighted sound pressure level of a continuous, steady sound that, within a
specified time interval T, has the same mean square sound pressure as a sound under
consideration whose level varies with time.
A-weighting
The human ear is most sensitive to frequencies in the range 1 kHz to 5 kHz. On each side of
this range the sensitivity falls off. A-weighting is used in sound level meters to replicate this
sensitivity and respond in the same way as the human ear.
Ambient Sound Level LAeq,T
Totally encompassing sound in a given situation at a given time usually composed of sound
from many sources near and far.
Specific Sound Level (also referred to as ‘site noise’) LAeq,Tr
Sound in the neighbourhood of a site that originates from the site i.e. the sound being
assessed. The equivalent continuous A-weighted sound pressure level produced by the
specific sound source at the assessment position over a given reference time interval.
Residual Sound Level LAeq,T
Ambient sound remaining at a given position in a given situation when the specific sound
source is suppressed to a degree such that it does not contribute to the ambient sound.
Background Sound Level LA90,T
The A-weighted sound pressure level of the residual sound at the assessment position that
is exceeded for 90% of a given time interval, T, measured using time weighting F.
Reference Time Interval, Tr
The specified interval over which the specific sound level is determined.
Free-field Level
The sound pressure level away from reflecting surfaces. NOTE Measurements made 1.2 - 1.5 metres above the ground and at least 3.5 metres away from other
reflecting surfaces are usually regarded as free-field.