Report Ref: R8109/10 Issue 4

Date: September November 2005











Agreement No. CE 18/2002 (EP)

Environmental Impact Assessment Study for

Construction of Helipads at

Peng Chau and Yung Shue Wan, Lamma Island



Helipad at
Yung Shue Wan, Lamma Island


Executive Summary



















BMT Asia Pacific Limited in Association With:


Hyder Consulting Limited

Asiatic Marine Limited

Archaeo-Environments Limited

Cosine Limited






Civil Engineering and Development Department






EIA Study for Helipad at Yung Shue Wan, Lamma Island –

Executive Summary




Job No:



R/8109/10 Issue 4




September November 2005



Prepared under the Management of:





Antony Wong


Environmental Consultant



Reviewed and Approved by:





Ben Ridley






Final ES_English(YSW)_Issue_4.doc



Distribution:  Original to Project Quality Records File

Page:  1   of    1



1        Project History and Site Selection                                                            1

1.1     General                                                                                                        1

1.2     Project Background                                                                                     1

1.3     Project Characteristics and Site Location                                                    1

1.4     Design Refinements                                                                                     2

1.5     Cumulative Effects                                                                                       2

2        construction dust                                                                                          5

3        Construction noise                                                                                         5

4        Helicopter Noise                                                                                              5

4.1     Impact Assessment                                                                                      5

4.2     Impact Mitigation Assessment                                                                      6

4.3     Evaluation of Residual Helicopter Noise Impacts                                         7

5        Waste MANAGEMENT                                                                                          8

5.1     Construction Phase                                                                                      8

5.2     Operational Phase                                                                                       8

6        water quality                                                                                                   8

6.1     Construction Phase                                                                                      8

6.2     Operational Phase                                                                                       8

7        Ecology                                                                                                              8

7.1     Construction Phase                                                                                      8

7.2     Operational Phase                                                                                       9

8        CULTURAL HERITAGE                                                                                           9

8.1     Construction Phase                                                                                      9

8.2     Operational Phase                                                                                       9

9        Conclusion                                                                                                       10

LIST OF Tables

Table 1.1           Summary Matrix for Evaluation of Helipad Site Options & Alternatives

Table 1.2           Summary of Yung Shue Wan Helipad Construction Programme

Table 4.1           Helicopter Usage at Yung Shue Wan during the years 2000 - 2004



Figure 1.1          Yung Shue Wan Helipad – Site Location

Figure 1.2          Yung Shue Wan Helipad Siting Options

Figure 1.3         Visual Illustrations

Figure 3.1         Noise Sensitive Receivers at Yung Shue Wan

Figure 4.1         Area Protected from Helicopter Approach / Departure Noise

Figure 4.2         Area Affected by Helicopter Manoeuvring Noise






1                    Project History and Site Selection

1.1               General

1.1.1          In August 2002 BMT Asia Pacific Limited (BMT) was awarded the contract for Agreement No. CE 18/2002: Environmental Impact Assessment Study for Construction of Helipads at Peng Chau and Lamma Island / Investigation by the Civil Engineering Office, Civil Engineering and Development Department (CEDD).

1.1.2          The Agreement requires the completion of Environmental Impact Assessment (EIA) studies for the construction and operation of two proposed permanent helipads: one at Peng Chau and one Yung Shue Wan, Lamma Island.  This report is the Executive Summary for the proposed Yung Shue Wan Helipad.

1.2               Project Background

1.2.1          The Project is ‘designated’ under Item B.2, Schedule 2 of the EIA Ordinance (EIAO) by virtue of being: “A helipad within 300m of existing or planned residential development”.  Accordingly, an Environmental Permit is required for the Project.

1.2.2          The Project is required solely by the Government Flying Service (GFS) for transporting North Lamma residents to urban areas for medical treatment in emergency situations, and is not for commercial use.

1.2.3          The previous Yung Shue Wan helipad ceased operation in May 1998 as it was in a congested area without clear approach and departure paths. Since this time there has been no permanent, dedicated helipad serving the local community. The community was until recently using the helipad at The Hongkong Electric Co. (HEC) Ltd’s Lamma Power Station – a distance of 2.75 km and a typical trip time of around 20 minutes by mini-ambulance from the North Lamma Clinic.  As a more acceptable interim measure, the Home Affairs Department (HAD) commissioned the development of a temporary helipad that been in operation at Yung Shue Wan since October 2003, pending the construction of a permanent helipad to serve the local community.

1.3               Project Characteristics and Site Location

1.3.1          The Project will be constructed by small diameter pre-bored piling in coastal waters at Kam Lo Hom (North), Yung Shue Wan [Figure 1.1].  The helipad deck will be located approximately 25 metres from the existing formed land, and an extension to the existing Emergency Vehicular Access (EVA) will be constructed to link with the proposed helipad.

1.3.2          The Project location and construction method were selected as the preferred options after due consideration of each of 7 site options / alternatives [Figure 1.2].  Table 1.1 presents a summary of the helicopter site option evaluation.  The construction programme can be broadly summarised as presented by Table 1.2.

Table 1.2     Summary of Yung Shue Wan Helipad Construction Programme

Construction Activity

Construction Period

Site Clearance

16-May-2006 to 22-Jul-2006


24-May-2006 to 16-Aug-2006

Pile Installation

17-Aug-2006 to 27-Jan-2007

Helipad Construction

29-Jan-2007 to 22-Jun-2007

E&M Works

30-May-2007 to 5-Jul-2007


6-Jul-2007 to 30-Jul-2007


1.3.3          Key Project details include: piling of approximately twenty-six piles 610 mm in diameter; and construction of a 25 metres long and 3.5 metres wide EVA; and a 25-metre diameter helipad.  Figure 1.3 presents two views of the proposed Yung Shue Wan helipad.

1.4               Design Refinements

1.4.1          Measures incorporated into the project design to avoid / reduce environmental impacts include construction by small diameter pre-bored piling, as opposed to dredging and reclamation, which practically eliminates concerns over potential waste management, water quality and marine ecology impacts; and reducing the width of the EVA from the standard 4.5m to 3.5m, with the effect that construction material requirements for the Project will be minimised.

1.4.2          As regards the operational project, helicopter noise is the main concern and in this regard the preferred site is relatively remote from the built environment yet still readily accessible from the local Clinic, while the angle of the helicopter flight path has been refined to avoid residual noise impacts on residences.

1.5               Cumulative Effects

1.5.1          One project identified in the vicinity that may contribute to cumulative effects is the construction of Drainage Services Department’s Yung Shue Wan Sewage Treatment Works (STW), due to commence in August 2007 for a 3-year construction period.  However, if the proposed helipad is still being constructed at the time that the STW construction commences, the existing temporary helipad will need to move back to the Lamma Power Station, and this will cause a delay in emergency service.  As such, CEDD and DSD have agreed to avoid overlapping these two projects.  Therefore, there would unlikely be any cumulative construction impacts.

1.5.2          According to the latest available programme, the Phase 2 Yung Shue Wan Development Engineering Works will commence in Year 2008 and have no potential cumulative effects.  Maintenance dredging for the HEC Lamma Power Station Navigation Channel Improvement was completed in early 2004, while marine works for HEC’s Lamma Power Station Extension Works were complete in 2003 prior to dredging for the navigation channel improvement.

Table 1.1          Summary Matrix for Evaluation of Helipad Site Options & Alternatives

Option / Alternative

Location [*]

Key Environmental Benefit(s)

Key Environmental Dis-benefit(s)

Other Key Considerations      (e.g., safety & access)



Yung Shue Wan North

·   No key environmental benefits.

·   Residual helicopter noise impacts from approach / departure to and from the helipad (i.e., flight path noise).[†]

·   Residual helicopter noise impacts from helicopter manoeuvring at the helipad.[‡]

·   Construction noise impact.

·   Helicopter flight safety concerns due to proximity to built-up area in Yung Shue Wan.

·   Potential limitations on land accessibility from Clinic due to the narrow and sometimes busy Yung Shue Wan Main Street.

Unacceptable in terms of flight safety and residual helicopter noise impacts.


Kam Lo Hom North

·    No significant construction phase impacts (noise assessment in Section 3).

·    No helicopter flight path noise impact (Section 4 refers).


·   Helicopter manoeuvring noise impact (Section 4 refers).

·   Joint-closest to the Clinic (i.e., highly accessible).

Residual helicopter manoeuvring noise impact, but no construction or access concerns.


Kam Lo Hom North

(EVA Extension)

·   No helicopter flight path or manoeuvring noise impacts due to remote site location.

·   Potentially significant visual impact from 270m long marine EVA.


·   Easy access from Clinic.

·   Marine safety risk (vessel collision) concerns due to EVA length.

Residual helicopter noise impacts unlikely to be significant, but unacceptable marine risk concerns.


Kam Lo Hom (South)







·   No significant construction phase impacts (land already formed).

·   No helicopter flight path or manoeuvring noise impacts due to remote site location.

·   No key environmental dis-benefits.

·   Joint-closest to the Clinic (i.e., highly accessible).

·   Land required for proposed Sewage Treatment Works (STW).

Residual helicopter noise impacts unlikely to be significant, but site required for proposed STW development.


Ferry Pier

·   No key environmental benefits.

·   Helicopter flight path and manoeuvring noise impacts as close to residences.

·   Construction noise impacts as close to residences.

·   Marine vessels by the ferry pier may infringe upon safe helicopter access / egress.

·   Potential limitations on land accessibility from Clinic due to the narrow and sometimes busy Yung Shue Wan Main Street.

Unacceptable in terms of flight safety and residual helicopter noise impacts.


Kam Lo Hom West

(Marine EVA)

·   No helicopter flight path or manoeuvring noise impacts due to remote site location.

·   Potential impacts on hard corals found along the sloping boulder seawall due to construction and operation of the marine EVA..

·   Easy access from Clinic.

·   Prevents marine access to proposed STW; interferes with sewage outfall construction & maintenance.

Residual helicopter noise impacts unlikely to be significant, but unacceptable in terms of access to proposed STW and sewage outfall.


Kam Lo Hom West

(Land EVA)

·   No helicopter flight path or manoeuvring noise impacts due to remote site location.

·   Ecology impact from secondary woodland clearance.

·   Easy access from Clinic.

Residual helicopter noise impacts unlikely to be significant, but unacceptable ecology impacts.

* Figure 1.2 refers.


2                    construction dust

2.1.1          Through proper implementation of dust control measures as required under the Air Pollution Control (Construction Dust) Regulation, construction dust can be controlled to acceptable level and no significant impacts are anticipated with the implementation of standard dust control measures.

3                    Construction noise

3.1.1          During the construction phase of the helipad, Powered Mechanical Equipment used for the helipad construction will be the primary noise sources.  The key noise generating activities include site clearance for the erection of site office, hoarding and fencing; temporary staging construction and demolition; pile installation, and construction of the helipad and EVA.

3.1.2          The potential noise levels arising from daytime construction activities were evaluated at both existing and planned representative noise sensitive receivers (NSRs), as illustrated by Figure 3.1.

3.1.3          Based on the construction schedule and plant inventory given, the highest unmitigated construction noise level was 74 dB(A) at NSR4.  This level is does not exceed the daytime noise standard of 75 dB(A) as stipulated in Table 1B, Annex 5 of EIAO-TM.  While no mitigation measures are required, it is recommended that the Contractor adopt good working practices in order to minimise construction noise as far as possible.

3.1.4          There shall be no overlap with the construction of the proposed STW, and hence cumulative construction noise impacts are not anticipated.

4                    Helicopter Noise

4.1               Impact Assessment

4.1.1          The sole noise source during the operational phase of the project will be from helicopter activities. At any one time, the helipad may be used by either one of two helicopter types deployed by Government Flying Service (GFS) for emergency casualty evacuation: Eurocopter Super Puma AS332 L2 and Eurocopter EC155 B1.

4.1.2          Helicopter noise will be generated when the helicopter is approaching and departing the helipad, and when it is manoeuvring on and over the helipad (i.e., hovering over the helipad; touchdown on the helipad; idling on the ground; and lift-off from the helipad surface to achieve a hover).

4.1.3          Based on the worst case scenario, the results show the highest predicted Lmax during the manoeuvring mode will be at NSR4.  A worst-case Lmax of 90 dB(A) is predicted when a ‘Super Puma AS332 L2’ is ‘hovering’, while a worst-case Lmax of 87 dB(A) is predicted when the ‘EC155 B1’ is in ‘lift off’ mode. Neither helicopter would exceed the Lmax limit of 85 dB(A) during the ‘idling’ phase.  The duration of residual impact during manoeuvring for both helicopter models would be very short (< 10 seconds).

4.1.4          In consultation with GFS, the angle of the flight path for the ‘EC 155 B1’ helicopter has been reduced to 80 degrees, whilst the flight path angle for the ‘Super Puma AS332 L2’ has been reduced to 70 degrees.  Accordingly, with flight confined within these ranges the predicted noise levels during helicopter approach / departure are able to comply with the Lmax 85 dB(A) limit, i.e., there is no helicopter flight path noise impact.

4.1.5          With reference to actual ‘casevac’ helicopter usage, and following the current trend as displayed by Table 4.1, GFS has agreed to give priority to the quieter ‘EC155 B1’ type helicopter whenever possible. Use of the ‘Super Puma AS332 L2’ will be restricted to special emergency situations only when a larger capacity helicopter is required.  As such, under normal operation there will only be a minor residual impact associated with manoeuvring by the ‘EC155 B1’.

Table 4.1     Helicopter Use for Yung Shue Wan ‘Casevac’ Operations during years 2000 – 2004


Total No. of Casevac from  0700 to 2200 hours1

Total No. of Casevac from 2200 – 0700 hours2

No. of Casevac Training Flights3


51 (1)




69 (7)




104 (13)




92 (7)




66 (1)




1.        The figures in brackets ( ) are the number of casevac flights carried out by Super Puma (or Sikorsky prior to 2004).

2.        Since 2003, all nighttime casevac has been undertaken using the EC155 B1 type helicopter only, although for the purpose of this noise impact assessment it cannot be discounted that the Super Puma may be required for nighttime casevac in future years.

3.        Five ‘casevac’ training flights were conducted to the Yung Shue Wan helipad in 2003 (i.e., an additional 4% of the total casevac flights).  As no such data is available for other years, the number of casevac training flights for 2000-2002 and 2004 have been calculated using the same % contribution.  It should be noted that GFS does not anticipate any increase in training flights in the short to medium term as the helicopter fleet was upgraded in 2001/02 and there are no plans to add additional types of helicopters.

4.2               Impact Mitigation Assessment

4.2.1          Realignment of the helicopter has enabled the avoidance of residual helicopter approach / departure noise impacts on approximately 420 dwellings from operation of the ‘EC155 B1’ type helicopter, and approximately 300 dwellings from operation of the ‘Super Puma’ type helicopter [Figure 4.1].

4.2.2          However, as noise levels from helicopter manoeuvring were predicted to exceed the Lmax 85 dB(A) limit at some NSRs for both helicopter types, the feasibility of adopting various mitigation measures was investigated.

4.2.3          The option of further extending the EVA to locate the helipad further offshore and further from the built environment was considered, however the EVA would need to be extended by approximately 270 metres for manoeuvring noise levels from both helicopter types to comply with the 85 dB(A) limit [Figure 1.2; ‘Alternative B2’].  As advised by the Marine Department, such as scenario was not preferred as the extension would reduce the area of navigable water between the ‘Alternative B2’ site and the existing ferry pier, and thereby increase the proximity of marine traffic in those waters and hence increase the risk of vessel collision. The Marine Department is also of the view that in order to minimise the traffic risk the proposed helipad location should not be extended any further offshore from the proposed ‘Alternative B1’ location.

4.2.4          Consideration was given to relocating the helipad approximately 150m further to the southwest [Figure 1.2; ‘Alternative E1’] to eliminate residual helicopter noise impacts. However, such relocation via a marine EVA would place the EVA across the proposed marine outfall from the proposed Yung Shue Wan Sewage Treatment Works [Figure 1.2 refers]. Such an arrangement is not supported by the Drainage Services Department, as it would impede outfall construction and maintenance. A land-based EVA [Figure 1.2; ‘Alternative E2’] would encroach on undisturbed woodland at the foot of Kam Lo Hom and would require tree feeling and land clearance, and such a scenario is not supported by the Agriculture, Fisheries & Conservation Department in terms of ecology / nature conservation.

4.2.5          In the case of the Yung Shue Wan helipad, physical structures such as noise barriers / enclosures cannot be constructed to provide effective noise shielding of the helicopter noise. This is because the noise is airborne (at an elevation of approximately 17 mPD) and will be emitted when the helicopter is at a linear distance of approximately 30 metres from the helipad. Constructing a noise barrier / enclosure to shield the anticipated helicopter noise is not practicable in terms of both engineering and flight safety.

4.2.6          Finally, consideration was given to the application of indirect mitigation measures that would require installation of acoustic insulation into all NSRs at which the predicted Lmax exceeds 85 dB(A). Effective indirect mitigation would require that NSR occupants comply with a ‘closed-window’ living environment during helicopter manoeuvring. However, it was considered that such measures would not be effective as occupants would receive no prior notice of an impending helicopter arrival, and because the noise impact duration would be so short (< 10 seconds) the impact event would be over by the time a response could be made.

4.3               Evaluation of Residual Helicopter Noise Impacts

4.3.1          Based on GFS data for the year 2000 - 2004, after taking into account all the practicable direct mitigation measures the residual impact from an ‘EC155 B1’ type helicopter would involve a 1-2 dB(A) exceedance of the 85 dB(A) limit approximately every 2.8 days. It is estimated that approximately 75 dwellings within 276 metres, and with a direct line of sight, of the helipad would be affected during ‘lift-off’ of the ‘EC155 B1’ type helicopter.  The residual impact from the ‘Super Puma AS332 L2’ type helicopter would involve a 3-5 dB(A) exceedance of the 85 dB(A) limit approximately every 24.3 days, affecting approximately 360 dwellings within the affected area of 386 metres from the helipad [Figure 4.2].

4.3.2          For both helicopter types the impact duration would last for 5-10 seconds per event, and the predicted magnitude, frequency and duration of residual impacts would not give rise to serious long-term environmental implications.

4.3.3          Residual noise may be audible during night-time from 7pm to 7am.  Following research undertaken to identify a suitable local or international standard to govern helicopter noise at night, it was identified that most literature on aircraft noise concerns relates to commercial airplane and helicopter noise.  However, during the public consultation exercise for the United States of America Federal Aviation Agency Hearings on [Non-military Helicopter Noise], there was a wide consensus among parties consulted that noise from emergency medical helicopter service is a tolerable necessity.

4.3.4          There is no standard on emergency helicopter noise at night, although under the Civil Aviation (Aircraft Noise) Ordinance (Cap 312) administrative means can be used to reduce the noise impact of helipad operations on NSRs.  However, restrictions on the number of helicopter flights during night time or restrictions on helipad operating hours are not practicable as the use concerned is for emergency service which will be on an as needed basis that cannot be controlled.

4.3.5          The best helicopter route over the least densely populated areas will be used for the proposed new helipad.  Considering that the helipad is for emergency service and this is a tolerable necessity, the construction of the helipad at the proposed location would therefore be acceptable.

4.3.6          In addition, GFS has agreed to avoid the use of the ‘Super Puma AS332 L2’ type helicopter whenever practicable, although should the need arise, the local community may lodge noise complaints with the Islands District Office by the following means: (Fax) 2815 2291; (e-mail); or (Post) Islands District Office, Harbour Building, 20th Floor, 38 Pier road, Central.

5                    Waste MANAGEMENT

5.1               Construction Phase

5.1.1          The waste management assessment analysed the type of activities associated with the construction of the helipad and the likely types of waste to be generated in order to outline measures to minimize impacts to the surrounding environment and where possible to minimize generation in the first place.

5.1.2          The waste volumes generated from Project construction will be small, with approximately 200m3 of uncontaminated silty-mud excavated from within the mini-bored pile casings between August 2006 and January 2007 likely to be transported by barge for marine disposal at the South Cheung Chau Spoil Disposal Area. There will also be approximately 80m3 of construction waste, 480 litres / month of chemical waste and 127 kg/week of general refuse generated throughout the construction period.

5.1.3          Through good practice and the mitigation measures that have been proposed for ensuring proper handling, storage, transportation and disposal of various types of waste / materials throughout the construction phase, no significant adverse impacts from waste management are anticipated.

5.2               Operational Phase

5.2.1          Organic (vegetation) waste is anticipated to be the only form of waste generated due to the operation of the helipad (from intermittent maintenance works).  However, the volume of such waste is expected to be negligible, and no adverse environmental impacts are anticipated during the operational phase.

6                    water quality

6.1               Construction Phase

6.1.1          The helipad and access link will be built using small diameter pre-bored piles, and there will be no dredging or reclamation works. Piling may cause some localised disturbance to the seabed sediment in the immediate vicinity of the works, although there will be no significant water quality impacts.  A silt curtain shall be implemented as good practice measures.

6.2               Operational Phase

6.2.1          Hydrodynamic effects of the constructed Project will be negligible, while there will be no operational discharges that could potentially translate into impacts on the marine environment.

7                    Ecology

7.1               Construction Phase

7.1.1          As the Project is of a small scale and is to be constructed by small diameter pre-bored piling, it will not result in any significant sub-tidal habitat loss, while there will be no loss at all of either inter-tidal or terrestrial habitat. The area of sub-tidal habitat permanently lost will be limited to the cumulative footprint area of the piles that support the access road link and the helipad – approximately 16 m2.

7.1.2          As determined through the water quality impact assessment, no significant water quality-induced ecological impacts are anticipated given the construction method, small scale of works and the weak tidal circulation around Yung Shue Wan that will promote rapid re-settlement of marine sediment. Furthermore, there is not anticipated to be any impact on the hard coral community identified along the artificial boulder seawall from pile installation provided good working practices are followed.

7.1.3          Accordingly, no specific mitigation measures are necessary, although the use of a silt curtain and other good practice measures to further minimize the potential for water quality-induced ecological impacts have been recommended.  The good practice measures include, for example, locating materials storage areas well away from the seawall, and ensuring the seal of the excavator used to remove sediment from within the bored pile casings is tightly closed to prevent ‘leakage’.

7.1.4          No terrestrial ecology impacts are anticipated given the construction method and distance to sensitive receivers.

7.2               Operational Phase

7.2.1          While the operational helipad will be a source of noise when in use that has the potential to disturb birds, and potentially affect butterflies through air turbulence, the helipad will be located approximately 50 metres from the nearest vegetated habitat where wildlife observations were made.  Furthermore, the absence of suitable shoreline in the vicinity of the Project area means that bird activity is very limited, and no observations were made of birds on the artificial sloping seawall or on the rocky shore to the west of the Project. Birds observed around Yung Shue Wan to the east and southeast would be able to freely move inshore (within the bay) if disturbed by helicopter noise. As such, no significant ecological impacts are anticipated during the operational phase of the Project.

8                    CULTURAL HERITAGE

8.1               Construction Phase

8.1.1          Marine geophysical survey identified three ‘items’ of potential marine archaeological value.  However, further evaluation concluded that all three items were associated with recent dredging for the seawall construction: (1) a drag mark associated with the dredged channel, (2) sediment deposits or a local depression from past dredging, and (3) either sediment deposits or a local depression from past dredging, and / or boulders.  The potential for submerged cultural remains in the vicinity of this dredged area is minimal, and no further field investigation was deemed necessary.

8.1.2          Evaluation of terrestrial cultural heritage in and around the study area at Yung Shue Wan revealed no archaeological sites, historic buildings or structures that could be impacted by the helipad development.

8.2               Operational Phase

8.2.1          The operational phase will not give rise to any cultural heritage impacts.

9                    Conclusion

9.1.1          The Project involves the construction and operation of a permanent helipad at Kam Lo Hom (North), Yung Shue Wan and is required mainly for transporting North Lamma residents to urban areas for medical treatment in emergency situations. Residents until recently had to 2.75 km (or 20 minutes journey time) from the North Lamma Clinic to use the helipad at HEC’s Lamma Power Station, although a temporary helipad now operates adjacent to the proposed permanent site as an interim measure.

9.1.2          The Project will be constructed by small diameter pre-bored piling, with the effect that material and waste handling requirements are minimised.  There will also be only highly localised and insignificant water quality and aquatic ecology impacts.  No dust or noise impacts are anticipated during the construction phase, and no impacts on cultural heritage are anticipated.

9.1.3          Helicopter noise is the main operational concern.  Of all 7 sites considered, the proposed one is optimally located in terms of accessibility from the local Clinic, avoidance of emergency vehicle travel through the built environment and the speed by which the permanent helipad can be developed and made available to the local community.  The helicopter flight path has been refined to avoid flight path noise impacts on residences.

9.1.4          A residual helicopter noise impact is predicted during manoeuvring at the helipad, although under normal operating conditions the impact level is predicted to be 1-2 dB(A), occurring approximately every 2.8 days. The impact duration would last for less than 10 seconds per event, and the predicted magnitude, frequency and duration of residual impacts would not give rise to serious long-term environmental implications.




[*] Figure 1.2 refers.

[†] Flight Path noise is the noise from the helicopter while in flight approaching to or departing from the helipad.

[‡] Manoeuvring noise is the noise from the helicopter while manoeuvring on or directly over the helipad.