6. GROUND-BORNE NOISE impact

Introduction

6.1 Potential ground-borne noise impacts likely arising during construction and operation phases of the Project have been evaluated and mitigation measures, if required, are recommended.

Environmental Legislation, Standards and Guidelines

Construction Phase

6.2 Ground-borne construction noise is under the control of the Noise Control Ordinance (NCO), the Environmental Impact Assessment Ordinance (EIAO), and their subsidiary Technical Memorandum. With reference to the Technical Memorandum for the Assessment of Noise from Places Other Than Domestic Premises, Public Places or Construction Sites (IND-TM) under the NCO, the criteria for noise transmitted primarily through the structural elements of the building or buildings should be 10dB(A) less than the relevant acceptable noise level (ANL).

6.3 Between 1900 and 0700 hours and all day on Sundays and public holidays, activities involving the use of powered mechanical equipment (PME) for the purpose of carrying out construction work is prohibited unless a Construction Noise Permit (CNP) has been obtained. A CNP may be granted in cases where the noise can be contained within the Acceptable Noise Level (ANL) at the NSRs. ANLs are assigned depending upon the Area Sensitivity Ratings (ASRs). The criteria applied for ground-borne noise assessment are summarised in Table 6.1 below.

Table 6.1 Ground-borne Construction Noise Criteria

	Ground-borne Construction Noise Criteria, dB(A)
GBNSR Description	Daytime (0700-1900 hrs) (except General Holidays & Sunday)	Daytime during general holidays and Sundays and all days during Evening (1900 to 2300 hrs)			Night-time (2300 to 0700 hrs)
		A	B	C	A	B	C
Education institutions	60/55 ^[a]	50	55	60	[b]
Domestic premises, hotels	65	50	55	60	35	40	45
Churches/temples, libraries, courts, performing arts, clinics	60	50	55	60	[b]

Notes:

[a] A 5dB(A) reduction to the ground-borne noise criteria is recommended for school during examination period.

[b] No sensitive use during this period.

6.4 For construction activities involving the use of TBM and PME during the restricted hours (i.e. 1900-0700 hours), it is necessary to apply for a Construction Noise Permit (CNP) under NCO. However, there is no guarantee that a CNP will be issued for the project construction. The Noise Control Authority will consider a well-justified CNP application, once filed, for construction works within restricted hours as guided by the relevant Technical Memoranda issued under the NCO. The Noise Control Authority will take into account contemporary conditions/ situations of adjoining land uses and any previous complaints against construction activities at the site before deciding whether to grant a CNP. Nothing in the EIA Report should bind the Noise Control Authority in making its decision. If a CNP is to be issued, the Noise Control Authority would include in the permit any condition it thinks fit. Failure to comply with any such conditions will lead to cancellation of the CNP and prosecution under the NCO.

Operation Phase

6.5 With reference to the IND-TM under the NCO, the criteria for noise transmitted primarily through the structural elements of the building or buildings should be 10dB(A) less than the relevant acceptable noise level (ANL). The same criteria are applied to all residential buildings, schools, clinics, hospitals, temples and churches.

6.6 The operational ground-borne railway noise criteria for the representative ground-borne noise sensitive receivers (GBNSRs) along the Project alignment are presented in Table 6.2 below.

Table 6.2 Operational Ground-borne Railway Noise Criteria

	Ground-borne Railway Noise Criteria, dB(A)
GBNSR Description	Day and Evening Periods (0900 to 2300 hrs)			Night-time Period (2300 to 0700 hrs)
	A	B	C	A	B	C
Churches/temples, schools, medical clinics, libraries, courts and performing arts	50	55	60	[a]
Domestic premises, hotels and hospitals	50	55	60	40	45	50

Note:

[a] No sensitive use during this period.

Identification of Ground-borne Noise Sensitive Receivers

6.7 In order to evaluate the construction and operational noise impacts likely to arise from the Project, representative GBNSRs (both existing and planned NSRs) within 300m of the Project boundary and at the most critical locations were selected, according to the criteria set out in the Annex 13 of EIAO-TM, observations from site visits and review of relevant land use plans including the Outline Zoning Plan (OZP) as presented in Figure Nos. NOL/ERL/300/C/XRL/ENS/M54/050 to 069, information available in the Statutory Planning Portal of the Town Planning Board (TPB) and land status plans published by Lands Department.

Construction Phase

6.8 Potential ground-borne noise impacts on GBNSRs during the construction phase would arise mainly from hydraulic breakers, drill rigs, pipe pile rigs and tunnel boring machine (TBM).

6.9 Under the assumption of worst-case scenario, two sets of representative GBNSRs were identified for the assessment of noise impact induced by (1) TBM operation for tunnelling; and (2) PME (i.e. hydraulic breakers, drill rigs and pile rigs) operation during the construction of adits. Representative GBNSRs identified along the alignment were designated for the assessment of TBM-induced ground-borne noise impact. As for the assessment of noise impact due to the use of PME for rock breaking / drilling, including hydraulic breakers, drill rigs and pipe pile rigs for the construction of adits, representative GBNSRs located in the closest proximity to the concerned areas were also identified. The identified GBNSRs are presented in Tables 6.3 and 6.4 and shown in NOL/ERL/300C/XRL/ENS/M53/002 to 025.

Table 6.3 Identified GBNSRs for Assessment of Ground-borne Construction Noise Impacts due to TBM operation

GBNSR No.	Location	Uses	Existing / Planned NSR	No. of Storeys
GN3	Yaumati Catholic Primary School (Hoi Wang Road)	School	Existing	8
GN4	Block 9, Charming Garden	Residential	Existing	23
GN5	Tower 5 Phase 1 Park Avenue	Residential	Existing	48
GN6	Hing Wong Mansion	Residential	Existing	16
GN7	Tai Fung Building (Block F) Cosmopolitan Estates	Residential	Existing	14
GN8	Chung Yew Building	Residential	Existing	15
GN9	West Kowloon Disciplined Services Quarters Block 1	Institutional	Existing	38
GN10	Fu Yun House, Fu Cheong Estate	Residential	Existing	8
GN12	SKH St. Mary's Church Mok Hing Yiu College	School	Existing	9
GN12a	Tack Ching Girls' Secondary School	School	Existing	8
GN13	Tower 6 Aqua Marine	Residential	Existing	46
GN14	HKIVE Haking Wong Waterfront Annex	School	Existing	2
GN14a	Lai Chi Kok Reception Centre	Institutional	Existing	8
GN26	426A Tsang Uk Tsuen	Residential	Existing	3
GN27	431A Tsang Uk Tsuen	Residential	Existing	3
GN28	510B Nam Hing Lei	Residential	Existing	3
GN29	630 Sheung Tsuen	Residential	Existing	2
GN31	DD110 LOT 482, Wang Toi Shan	Residential	Existing	1
GN33	348 Tsat Sing Kong	Residential	Existing	1
GN34	349 Tsat Sing Kong	Residential	Existing	2
GN35	374 Chuk Yau Road	Residential	Existing	1
GN36	DD104 LOT 1786, Chuk Yau Road	Residential	Existing	2
GN37	DD104 LOT 1396, Yau Tam Mei Tsuen, Chuk Yau Road	Residential	Existing	1
GN37a	Chun Shin Road, Yau Tam Mei Tsuen	Residential	Existing	2
GN38	45 Wai Tsai Tsuen	Residential	Existing	2
GN38a	Petrus Avenue House 21 Phase 1 The Vineyard	Residential	Existing	3
GN38b	China Bible Seminary	School	Existing	3
GN39	62D Wai Tsai Tsuen	Residential	Existing	3
GN40	House 1, Green Crest	Residential	Existing	3
GN41	House A73 Maple Gardens	Residential	Existing	3
GN42	House A78 Maple Gardens	Residential	Existing	3
GN43	Planned Development	Residential	Planned	N/A
GN44	House 5 Phase A Royal Palms	Residential	Existing	3
GN45	Village house in Mai Po	Residential	Existing	1

Table 6.4 Identified GBNSRs for Assessment of Ground-borne Construction Noise Impacts due to the Construction of Adits

GBNSR No.	Location	Uses	Existing / Planned NSR	No. of Storeys
GN12a	Tack Ching Girls' Secondary School	School	Existing	8
GN14a	Lai Chi Kok Reception Centre	Institutional	Existing	8
GN14b	Ward A, Ex-Lai Chi Kok Hospital^(1)	Hostel	Existing	2
GN14c	Po Leung Kuk Tong Nai Kan College	School	Existing	7
GN15	40A Cheung Hang Village	Residential	Existing	2
GN16	Tower 6 Regency Park	Residential	Existing	17
GN17	Block 21 Wonderland Villas	Residential	Existing	20
GN18	Block 2 Greenknoll Court	Residential	Existing	31
GN18a	Block 17 Wonder Land	Residential	Existing	21
GN19	Tower B Kwai Sing Centre	Residential	Existing	28
GN20	Block B Hutchison Estate	Residential	Existing	23
GN21	184 Yau Ma Hom Resite Village	Residential	Existing	3
GN21a	274 Yau Ma Hom Resite Village	Residential	Existing	3
GN22	18 Da Chuen Ping Village	Residential	Existing	3
GN22a	37 Chung Kwai Chung Tsuen	Residential	Existing	3
GN23	35 Sheung Kwai Chung Village	Residential	Existing	4
GN24	Sau Shan House, Cheung Shan Estate	Residential	Existing	25
GN25	Tsuen Wan Lutheran School	School	Existing	7
GN25a	DD 114 LOT 1405 Sheung Tsuen	Residential	Existing	2
GN30	51A Leung Uk Tsuen	Residential	Existing	3
GN35	374 Chuk Yau Road	Residential	Existing	1

Remark:

(1) The future usage of Ex-Lai Chi Kok Hospital was announced to be converted as holiday camp, hostel, arts and cultural village, educational institute under Revitalising Historic Buildings Through Partnership Scheme.

Operation Phase

6.10 Sensitive receivers along the alignment generally include educational institutions, performing arts and domestic premises. Domestic premises are taken into account during both the daytime and night time periods, while performing arts and educational institutions are considered to be noise sensitive during daytime and evening only.

6.11 Representative operational phase GBNSRs have been identified and are listed in Table 6.5. Their locations are shown in NOL/ERL/300C/XRL/ENS/M53/000 to 025. As a conservative approach, it is assumed that the sensitive receivers are not affected by any IF. For the interface between WKT and West Kowloon Cultural District (WKCD), MTR and WKCD Authority will further liaise with each other for dealing with the details of interfacing issues and mitigation measures.

6.12 Information necessary including the geometry of the closest point on a GBNSR relative to the alignment as well as the structure characterisation for noise prediction is shown in Table 6.5.

Table 6.5 Operation Phase Ground-borne Railway Noise Sensitive Receivers

GBNSR No.	Location	Uses	Type of Area Containing NSR	Degree to which NSR is affected by IF^(a)	ASR	No. of storeys	Building Type^(b)	Basement^(c)	TCF^(h)	BCF Type^(g)	Slant Distance to nearest Track, m
GN1	Future Development at West Kowloon Cultural District	Performing Art	Urban	Not Affected	B	N.A.	N.A.	N.A.	R	2	31
GN2	Future Development at West Kowloon Cultural District	Performing Art	Urban	Not Affected	B	N.A.	N.A.	N.A.	R	2	47
GN2a	WKT Topside Development	Comprehensive Development Area	Urban	Not Affected	B	N.A.	N.A.	N.A.	R	2	N.A.
GN2b	WKT Topside Development	Comprehensive Development Area	Urban	Not Affected	B	N.A.	N.A.	N.A.	R	2	N.A.
GN2c	WKT Topside Development	Comprehensive Development Area	Urban	Not Affected	B	N.A.	N.A.	N.A.	R	2	N.A.
GN2d	Block 6 Phase 1 Sorrento	Residential	Urban	Not Affected	B	52	0	0	R	2	47
GN2e	Man King Building	Residential	Urban	Not Affected	B	19	0	0	R	2	62
GN3	Yaumati Catholic Primary School (Hoi Wang Road)	School	Urban	Not Affected	B	8	0	0	S	1	30
GN4	Block 9, Charming Garden	Residential	Urban	Not Affected	B	23	0	0	S	3	32
GN5	Tower 5 Phase 1 Park Avenue	Residential	Urban	Not Affected	B	48	0	0	R	2	36
GN6	Hing Wong Mansion	Residential	Urban	Not Affected	B	16	0	0	R	1	34
GN7	Tai Fung Building (Block F) Cosmopolitan Estates	Residential	Urban	Not Affected	B	14	0	0	R	1	34
GN8	Chung Yew Building	Residential	Urban	Not Affected	B	15	0	0	R	1	34
GN9	West Kowloon Disciplined Services Quarters Block 1	Institutional	Urban	Not Affected	B	38	0	0	S	3	40
GN10	Fu Yun House, Fu Cheong Estate	Residential	Urban	Not Affected	B	8	0	0	S	3	35
GN11	Planned Nam Cheong Station Properties Development	Residential	Urban	Not Affected	B	N.A.	N.A.	N.A.	S	3	32
GN11a	Planned Residential Development in Site 6	Residential	Urban	Not Affected	B	N.A.	N.A.	N.A.	S	3	N.A.
GN12	SKH St. Mary's Church Mok Hing Yiu College	School	Urban	Not Affected	B	9	0	0	S	3	42
GN12a	Tack Ching Girls' Secondary School	School	Urban	Not Affected	B	8	0	0	S	3	50
GN13	Tower 6 Aqua Marine	Residential	Urban	Not Affected	B	46	0	0	S	1	40
GN14	HKIVE Haking Wong Waterfront Annex	School	Urban	Not Affected	B	2	2	0	S	0	34
GN14a	Lai Chi Kok Reception Centre	Institutional	Other	Not Affected	B	8	0	0	R	2	52
GN14b	Ward A, Lai Chi Kok Hospital	(e)	Other	Not Affected	B	2	2	0	R	0	90
GN15	40A Cheung Hang Village	Residential	Low Density Residential Area	Not Affected	A	2	2	0	R	0	235
GN16	Tower 6 Regency Park	Residential	Other	Not Affected	B	17	0	0	R	2	248
GN17	Block 21 Wonderland Villas	Residential	Other	Not Affected	B	20	0	0	R	2	275
GN18	Block 2 Greenknoll Court	Residential	Urban	Not Affected	B	31	0	0	R	2	93
GN18b	Kwai Ying Building	Residential	Urban	Not Affected	B	19	0	0	R	2	76
GN19	Tower B Kwai Sing Centre	Residential	Urban	Not Affected	B	28	0	0	R	2	57
GN19a	Ming Tak Building	Residential	Urban	Not Affected	B	6	0	0	R	2	59
GN20	Block B Hutchison Estate	Residential	Urban	Not Affected	B	23	0	0	R	2	53
GN21	184 Yau Ma Hom Resite Village	Residential	Other	Not Affected	B	3	1	0	R	0	73
GN22	18 Da Chuen Ping Village	Residential	Rural Area	Not Affected	A	3	1	0	R	0	87
GN23	35 Sheung Kwai Chung Village	Residential	Rural Area	Not Affected	A	4	1	0	R	0	98
GN24	Sau Shan House, Cheung Shan Estate	Residential	Urban	Not Affected	B	25	0	0	R	2	124
GN25	Tsuen Wan Lutheran School	School	Urban	Not Affected	B	7	0	0	R	2	124
GN26	426A Tsang Uk Tsuen	Residential	Rural	Not Affected	A	3	1	0	S	0	23
GN27	431A Tsang Uk Tsuen	Residential	Rural	Not Affected	A	3	1	0	S	0	26
GN28	510B Nam Hing Lei	Residential	Rural	Not Affected	A	3	1	0	S	0	26
GN29	630 Sheung Tsuen	Residential	Rural	Not Affected	A	2	2	0	S	0	28
GN30	51A Leung Uk Tsuen	Residential	Other^(f)	Not Affected	B	3	1	0	S	0	113
GN30a	Village Zone West Boundary, Leung Uk Tsuen	Residential	Other^(f)	Not Affected	B	3	1	0	S	0	61
GN30b	Village house in Leung Uk Tsuen	Residential	Other^(f)	Not Affected	B	3	1	0	S	0	46
GN31	DD110 LOT 482, Wang Toi Shan	Residential	Other^(f)	Not Affected	B	1	2	0	R	0	19
GN33	348 Tsat Sing Kong	Residential	Rural Area	Not Affected	A	1	2	0	S	0	25
GN34	349 Tsat Sing Kong	Residential	Rural Area	Not Affected	A	2	2	0	S	0	25
GN35	374 Chuk Yau Road	Residential	Rural Area	Not Affected	A	1	2	0	S	0	46
GN36	DD104 LOT 1786, Chuk Yau Road	Residential	Rural Area	Not Affected	A	2	2	0	S	0	31
GN37	DD104 LOT 1396, Yau Tam Mei Tsuen, Chuk Yau Road	Residential	Rural Area	Not Affected	A	1	2	0	S	0	30
GN37a	Chun Shin Road, Yau Tam Mei Tsuen	Residential	Rural Area	Not Affected	A	2	2	0	S	0	53
GN38	45 Wai Tsai Tsuen	Residential	Rural Area	Not Affected	A	2	2	0	S	0	33
GN38a	Petrus Avenue House 21 Phase 1 The Vineyard	Residential	Low Density Residential Area	Not Affected	A	3	1	0	S	0	34
GN38b	China Bible Seminary	School	Rural Area	Not Affected	A	3	1	0	S	0	29
GN39	62D Wai Tsai Tsuen	Residential	Rural Area	Not Affected	A	3	1	0	S	0	34
GN40	House 1, Green Crest	Residential	Low Density Residential Area	Not Affected	A	3	1	0	R	0	42
GN41	House A73 Maple Gardens	Residential	Low Density Residential Area	Not Affected	A	3	1	0	S	0	39
GN42	House A78 Maple Gardens	Residential	Low Density Residential Area	Not Affected	A	3	1	0	S	0	38
GN43	Planned Development	Residential	Low Density Residential Area	Not Affected	A	N.A.	N.A.	N.A.	S	3	31
GN44	House 5 Phase A Royal Palms	Residential	Low Density Residential Area	Not Affected	A	3	1	0	S	0	51
GN45	Village house in Mai Po	Residential	Rural Area	Not Affected	A	1	2	0	S	0	32

Remark:

(a) As a conservative assessment, it is assumed that the sensitive receivers will not be affected by any IF.

(b) Building Type: 0 – Heavy Tall Structures; 1 – 2 to 4 storeys medium height; 2 – 1 to 2 storeys.

(c) Basement: 0 – no basement; 1 – basement.

(d) N.A.: Information for future property development is not available during the preparation of report.

(e) The future usage of Ex-Lai Chi Kok Hospital was announced to be converted as holiday camp, hostel, arts and cultural village, educational institute under Revitalising Historic Buildings Through Partnership Scheme.

(f) "Area other than those above" as the SSS by virtue of its size and characteristics plays a major role in determining the type of area within which the NSR is located in accordance with the Technical Memorandum for the Assessment of Noise from Places other than Domestic Premises, Public Places or Construction Sites.

(g) BCF Type: 0 – No piles, with BCF; 1 – Piles not to rock, with BCF; 2 – Piles to rock & tunnel in rock, no BCF; 3 – Piles to rock & tunnel not in rock, with BCF

(h) TCF: R – Tunnel in rock, no TCF; S – Tunnel in soil, with TCF

Potential Sources of Impact

Construction Phase

6.13 Potential ground-borne noise impacts on GBNSRs during the construction phase will arise mainly from TBM operation, as well as PME for rock breaking/drilling including breakers, drill rigs and pipe pile rigs. The standard working hours of PME will be from 0700 to 1900 hours and the TBM will be operated on a 24 hour basis. The operation of TBM during restricted hours should be governed by the control of CNP under NCO. Regardless of the results of construction noise impact assessment for restricted hours, the Noise Control Authority will process CNP application, if necessary, based on the NCO, the relevant technical memoranda issued under the NCO, and the contemporary conditions/situations of adjoining land uses and any previous complaints against construction activities at the site before making his decision in granting a CNP.

Operation Phase

6.14 When trains operate in tunnels that are located in close proximity to occupied structures, there is a possibility that vibrations associated with train passbys will be transmitted through the ground and structure, and be radiated as noise in the occupied spaces within the structure. The transmitted noise through the structure may have impact to the GBNSRs.

Ground-borne Noise Prediction Methodology

Construction Phase

6.15 The project methodology adopted for assessment is recommended in The Transit Noise and Vibration Impact Assessment^[[1]] published by U.S. Department of Transportation Federal Transit Administration (FTA) (FTA Guidance Manual). This methodology has been previously adopted for ground-borne noise assessment in approved Kowloon Southern Link (KSL) EIA Study (EIA Register No. AEIAR-083/2005) and West Island Line (WIL) EIA Study (EIA Register No. AEIAR-126/2008). The empirical based prediction model used to predict noise levels at the representative NSRs adopts the following equation:

L = FDL + LSR + BCF + BVR + CTN + SAF

where

L	ground-borne noise level within the structure, re: 20 μ-Pascal
FDL	force density level for the TBM in rock, mixed face or soil, re: 1 N/m0.5 in SI unit
LSR	unit force incoherent line source response for the ground, re: 10^-8 m/s/(1 N/m0.5) in SI unit
BCF	vibration coupling loss factor between the soil and the foundation, relative level
BVR	building vibration reduction or amplification within a structure from the foundation to the occupied areas, relative level
CTN	Conversion from floor and wall vibration to noise, 10^-8 m/s to 20 μ Pascal
SAF	Safety margin to account for project uncertainties

TBM-induced Ground-borne Noise Impact Assessment

6.16 The TBM-induced ground-borne noise levels were calculated by incorporating the algorithms in a 3-D model, MoleRat, developed by Wilkinson Murray Limited.

6.17 The prediction model adopted is based on the equation discussed in Section 6.15 and is referenced from the FTA Guidance Manual. The prediction components particular for TBM-induced ground-borne noise are described in following sections.

Ground-Borne Noise Level within the Structure (L)

6.18 TBM-induced ground-borne noise would have an impact with frequency, conservatively, up to about 160 Hz and 400Hz for tunnels situated in soil and rock respectively. Above these frequencies, the material attenuation of the ground would reduce the amplitude of the propagating waves below which there would be adverse impact. Thus, structure-borne noise levels were presented in 1/3 octave bands over the frequency range of 12.5 Hz to 400 Hz.

Force Density Level (FDL)

6.19 FDL values to be adopted for assessment were reference from WIL EIA Study in which the assessment adopted the vibration measurement taken during the passby of a TBM operating in soil and rock along the MTR Lok Ma Chau (LMC) Extension. Measurements were performed underground in an access shaft adjacent to the alignment at 7m setback from tunnel centreline. The associated line source response (LSR) was obtained from surface and borehole impact tests performed on similar soil and rock geology. On the assumption of a TBM source length of 10m, the FDL values in soil and rock are shown in Appendix 6.1. FDL is dependent upon TBM diameter and ground condition, but these factors may be represented by the power to be used by the TBM. The outside diameter (OD) of TBM to be adopted for the construction of the Project will be about 9.3m and a standard drive rate of 200m/month was assumed though the actual rate will be dependent on the ground condition. Average rates were reference from the case in LMC with 11 m/day in soft ground and 8.0 m/day in rock. While the outside diameter of TBM used for the construction of LMC is 8.8m, and therefore FDL values of the proposed TBM are therefore considered to be of comparable magnitude with the TBM used in LMC.

6.20 Measurement results indicated that the FDL for the TBM in rock is considerably higher than that in soil, especially at low frequencies. As a conservative approach, the FDL values in mixed face geology rock have been assumed to be same as that in rock.

Line Source Response (LSR)

6.21 The LSR determines the vibration levels or attenuation in the ground as a function of distance caused by an incoherent line source of unit force point impacts, with line source (TBM) orientated along the alignment.

6.22 LSR has already been measured in Hong Kong at a number of locations, and the most relevant measured results (taking into account the ground type) will be used for the calculations. The LSR was referenced from the data adopted in KSL and WIL EIA Studies. The LSR for WIL EIA Study were determined based on the results of borehole impact tests performed in rock, soil and close to the rock head both on the soil side and the rock side, with receiver vibration data taken at many setback distances. Appropriate LSR has been selected accordingly with consideration of geological characteristics along alignment. Mostly the rock through which the tunnel will pass is granite with highly decomposed granite and alluvium on top, and the LSR values used from WIL are those obtained by testing in the same rock and ground material. LSR for different geological characteristics have been presented in Appendix 6.2.

6.23 The LSR values used for assessment are shown in Table 6.6.

Table 6.6 LSR Values used for Assessment

Alignment						Corresponding LSR selected from WIL EIA Study
Chainage (Northbound)		Chainage (Southbound)		Track Depth (m)	Rockhead Depth (m)	LSR Name	Borehole Depth (m)	Rockhead Depth (m)
From	To	From	To
116+015	116+815	116+000	116+800	No GBNSR
116+815	118+015	116+800	118+000	30	60	D012-18m	18	34.4
118+015	118+465	118+000	118+450	40	40	D012-41.4m	41.4	34.4
118+465	119+695	118+450	119+680	27	55	D012-18m	18	34.4
119+695	119+815	119+680	119+800	60	25	D049-60.4m	60.4	19.4
119+815	119+915	119+800	119+900	80	25	D049-87.8m	87.8	19.4
119+915	120+015	119+900	120+000	110	25	D049-87.8m	87.8	19.4
120+015	122+115	120+000	122+100	No GBNSR
122+115	122+315	122+100	122+300	65	15	D064-66.7m	66.7	14.7
122+315	122+415	122+300	122+400	45	10	D064-54.6m	54.6	14.7
122+415	122+515	122+400	122+500	38	20	D028-44.3m	44.3	22.3
122+515	122+675	122+500	122+660	38	25	D018-39.8m	39.8	27.6
122+675	122+975	122+660	122+960	27	30	D002-19.6m	19.6	24.1
122+975	123+175	122+960	123+160	20	32	D012-18m	18	34.4
123+175	123+515	123+160	123+500	17	13	D018-39.8m	39.8	27.6
123+515	125+365	123+500	125+350	20	25	D002-19.6m	19.6	24.1
125+365	125+465	125+350	125+450	25	15	D018-39.8m	39.8	27.6
125+465	125+565	125+450	125+550	50	10	D064-54.6m	54.6	14.7
125+565	125+665	125+550	125+650	75	10	D049-87.8m	87.8	19.4
125+665	125+765	125+650	125+750	95	10	D049-87.8m	87.8	19.4
125+765	131+815	125+750	131+800	No GBNSR
131+815	132+365	131+800	132+350	100	10	D049-87.8m	87.8	19.4
132+365	132+835	132+350	132+820	90	15	D049-87.8m	87.8	19.4
132+835	133+035	132+820	133+020	65	10	D064-66.7m	66.7	14.7
133+035	133+765	133+020	133+750	55	15	D064-54.6m	54.6	14.7
133+765	134+135	133+750	134+120	80	10	D049-87.8m	87.8	19.4
134+135	135+515	134+120	135+500	185	20	D049-87.8m	87.8	19.4
135+515	136+465	135+500	136+450	No GBNSR
136+465	136+695	136+450	136+680	95	25	D049-87.8m	87.8	19.4
136+695	136+915	136+680	136+900	35	20	D018-39.8m	39.8	27.6
136+915	137+235	136+900	137+220	35	35	D002-33.7m	33.7	24.1
137+235	137+595	137+220	137+580	35	40	D002-19.6m	19.6	24.1
137+595	137+835	137+580	137+820	33	55	D012-18m	18	34.4
137+835	137+935	137+820	137+920	33	33	D002-33.7m	33.7	24.1
137+935	138+115	137+920	138+100	33	50	D012-18m	18	34.4
138+115	138+465	138+100	138+450	33	80	D012-18m	18	34.4
138+465	139+115	138+450	139+100	35	50	D012-18m	18	34.4
139+115	139+315	139+100	139+300	35	30	D018-39.8m	39.8	27.6
139+315	139+815	139+300	139+800	40	20	D028-44.3m	44.3	22.3
139+815	139+905	139+800	139+890	38	38	D012-41.4m	41.4	34.4
139+905	140+215	139+890	140+200	40	60	D012-18m	18	34.4
140+215	141+115	140+200	141+100	30	50	D012-18m	18	34.4
141+115	141+315	141+100	141+300	30	30	D002-33.7m	33.7	24.1
141+315	141+671	141+300	141+656	27	40	D012-18m	18	34.4

Building Coupling Factor (BCF)

6.24 In general, larger and heavier structures have greater vibration attenuation than smaller and lighter structures. The recommended practice established within FTA Manual has been followed. Receivers in this study were divided into 4 types according to its structures and have different BCF attenuation as below:

Type 0 – Large masonry buildings

Type 1 – 2-4 storeys masonry buildings

Type 2 – 1-2 storeys buildings

Type 3 – Single family detached residences

6.25 The BCF for different types of structure is presented in Appendix 6.3. It is indicated that larger and heavier structures have greater vibration attenuation than smaller and lighter structures. In fact, the extent of the attenuation is governed by the difference in mechanical impedance between the soil and the foundation, with impedance being determined by differences in mass and stiffness within the soil and foundation. For structures founded on rock, there is no impedance contrast between the soil and the foundation, as a conservative approach, the BCF is considered to be zero.

6.26 It has been assumed that buildings up to three stories in height do not have piles, and buildings over this height do, unless specific information is available for assessment. For most of the high-rise buildings, details of the piles are available, including whether the piles are to rock or are friction piles. In those cases where no details of the piles were available, a worst case scenario has been assumed; that the piles are to rock such that no coupling loss was taken into account.

Building Vibration Response (BVR)

6.27 The BVR is generally determined by three factors as described below:

I. Resonance amplification due to floor, wall and ceiling spans: This resonance amplification is usually an issue for small and lightweight houses. In large, heavy framed structures, generally multi-floor concrete construction, structural resonances usually occur at sub-audible frequencies, with small resonance amplification due to massive structural elements having low mobility. FTA Manual recommends a 6 dB correction at the likely natural frequency of structures to account for structural resonances. The corrections given in Appendix 6.4 were adopted, as was the case for the WIL EIA Study.

II. Floor-to-floor attenuation: A floor-to-floor attenuation of 2 dB reduction per floor was assumed. Where there is a multi-floor occupancy, only the structure-borne noise impact on the lowest occupied floor is considered.

III. Attenuation across a structure, in the direction away from the alignment: When the noise sensitive area is situated in the back of the building away from the alignment, vibration attenuation across a structure would occur. Attenuation of 2 dB reduction was considered in this study, and this is conservative for large setbacks.

Conversion to Noise (CTN)

6.28 Based on FTA Manual, a -27 dB correction for conversion of vibration (re: 10^-9 m/s) in room walls, floors and ceiling to noise (re: 20 micro Pa) was assumed in this study.

Safety Factor (SAF)

6.29 To tackle the problem of differences in overall predicted and measured A-weighted noise levels, a safety factor was applied in the model. As a conservative approach, a 10 dB safety factor was adopted to account for uncertainty and variation in geological characteristics.

PME-induced Ground-borne Noise Impact

6.30 For the assessment of PME-induced ground-borne noise, reference was made to the assessment approach, source terms and transmission factors adopted in the approved KSL and WIL EIA Studies. The reference source levels adopted for assessment are given in Table 6.7.

Table 6.7 Reference Source Levels

Plant	Vibration (rms) at reference distance of 5.5m from source^[[2]]	Vibration (ppv) at distance 2m from source
Hydraulic Breaker	0.298 mm/s	-
Drill Rig	0.536 mm/s	-
Pile Rig	-	19.3 mm/s

Soil Damping

6.31 Internal losses of soil would cause the vibration amplitude to decay against the propagation distance and the decay relationship is based on the equation set out in the Transportation Noise Reference Book^[[3]].

V(R) = V(R_o) ´ e^{-2pf h R/2c}.

6.32 The velocity amplitude V is dependent on the frequency f in Hz, the soil loss factorh, the wave speed c in m/s, the distance R from the source to the GBNSR. The properties of soil materials are shown in Table 6.8.

Table 6.8 Wave Propagation Properties of Soil

Soil Type	Longitudinal Wave Speed c, m/s	Loss Factor, h	Density, g/cm^3
Soil	1500	0.5	1.7
Rock	3500	0.01	2.65

6.33 It was assumed that no damping attenuation would apply for propagation in rocks. Therefore, soil damping for GBNSRs with piling foundation on rockhead was not required.

Coupling Loss into Building Structures

6.34 This was as assumed for TBM-induced ground-borne noise calculation above.

Loss Per Floor

6.35 This was as assumed for TBM-induced ground-borne noise calculation above.

Conversion from Floor Vibration to Noise Levels

6.36 This was as assumed for TBM-induced ground-borne noise calculation above.

Operation Phase

6.37 The railway ground-borne noise levels were calculated by incorporating the algorithms in a 3-D model, MoleRat, developed by Wilkinson Murray Limited.

6.38 The methodology adopted for the ground-borne noise impact assessment is in accordance with the procedures outlined in FTA Guidance Manual and High-Speed Ground Transportation Noise and Vibration Impact^[[4]^](FRA High-Speed Guidance Manual). This is a similar methodology as used for WIL EIA Study. The ground-borne noise level in GBNSRs were calculated as follows:

L = FDL + TIL + TOC + TCF + LSR + BCF + BVR + CTN + SAF

where

L	ground-borne noise level within building, in dB
FDL	force density level, in dB re 1N/m^1/2
TIL	trackform attenuation or insertion loss, relative level
TOC	turnout and crossover factor
TCF	vibration coupling between the tunnel and the ground for soil based tunnels, relative level
LSR	line source transfer mobility, in dB re 1(nm/s)/(Nm^0.5)
BCF BVR CTN SAF	adjustment to account for building coupling loss, in dB building vibration amplification within the structure, in dB conversion from vibration to noise within the building, in dB safety factor to account for wheel/rail condition and uncertainties in ground conditions, in dB

Force Density Levels (FDL)

6.39 Since high speed trains in 200km/h are currently not running in Hong Kong and details of the CRH trains proposed for the Project are not available during the preparation of EIA study, the vibration source levels (force density levels, FDL) were referenced from the FRA High-Speed Guidance Manual, which is designed for assessment when details of train type is unknown. The level adopted for train type of China Railway High-Speed (CRH) train has been based on the noisiest train reported (i.e. Acela) in FRA High-Speed Guidance Manual and is shown in metric units in Appendix 6.5. The highest level among four trains as given in FRA High-Speed Guidance Manual was adopted for assessment. This level is based on a standard high speed train trackform of a moderate to high stiffness, similar to the proposed 50kN/mm.

6.40 The adopted FDL is for a train on rails in moderate operational condition and a rail maintenance programme will be developed for the Project. This FDL will be considered to identify the ground-borne noise mitigation measures for the Project.

6.41 In accordance with Table 8-2 of the FRA High-Speed Guidance Manual, the FDL was adjusted for speed as 20 log S/Sref.

Trackform Alternatives or Insertion Loss (TIL)

6.42 Trackform attenuation has two components: the magnitude of the attenuation and the frequency above which attenuation occurs (resonance frequency of the trackform). Generally, more compliant trackform support and more massive elements in the trackform will result in a greater magnitude of attenuation occurring at lower frequencies. In addition, more massive trackform elements would take up more space in tunnels and may cause spatial incompatibilities that are difficult to be overcome in the design.

6.43 The ground-borne noise levels at GBNSRs were calculated initially for a trackform of embedded concrete sleepers with slightly resilient fixings (approximately 50kN/mm) on top (e.g. Rheda system). An example of proposed trackform is presented in Appendix 6.11.

6.44 When the appropriate trackforms to meet the noise criteria had been identified, consideration was then given to the action to be taken if it is found that ground-borne noise levels exceed the criteria after construction. Given there would be uncertainty on on-site/train specific data, a 600mm deep provision will be provided for the tunnel to allow for further enhancement of mitigation measures, such as installation of isolated slab track (IST), if required. An example of low noise trackform is presented in Appendix 6.11. As such, the currently proposed trackform (concrete sleepers with slightly resilient fixings) can be replaced with low noise trackfrom where practicable and necessary to accomplish noise reduction of up to 15 dB(A), subject to the extent of low noise trackform provided and the dominant frequency of FDL and LSR, as a contingency measure. Changing of the tunnel dimensions would therefore not be required if these contingency measures have to be in place. Further measurements would be conducted to check the accuracy of the noise prediction during the tunnel construction where necessary.

Tunnel Coupling Factor (TCF)

6.45 Tunnel Coupling Factor (TCF) is the vibration coupling between the tunnel and the ground for soil based tunnels. Vibration attenuation occurs at the interface between a transit tunnel and the surrounding soil on account of a mismatch in the soil and tunnel wall impedances. The TCF adopted in this study was referenced from the WIL EIA Study. In general, tunnels borne in rock generally do not exhibit any significant vibration attenuation across the tunnel rock interface, thus no TCF attenuation is applied for rock-founded tunnels. However, with reference to the FTA Manual, a 3dB(A) and 5dB(A) reduction in ground-borne noise level was assumed for cut-and-cover tunnels and station structures respectively in soil.

6.46 For tunnels in soil, separate tests have been carried out in Hong Kong, and these are reported in the WIL EIA study. The results showed a strong relationship to BCF, and the TCF adopted is the maximum envelope of the measured TCF and the type 2 BCF, as shown in Appendix 6.6.

Turnout and Crossover Factor

6.47 At points and crossings, where the wheel transitions from one rail to another, the sudden loading/unloading of the leading and trailing rails results in increased broad band vibration levels over that of plain line continuous rail. While it is not possible to machine grind the rails through either the points or crossings, surface deterioration would often be evident. For standard level turnouts and crossings receiving average maintenance, the FTA Manual recommends a correction of 10dB. For modern inclined turnouts in good condition, where impact loads are lessened, a correction of 5dB would be appropriate. As in the recent WIL EIA study, 5dB(A) adjustment was added for inclined turnout.

Line Source Response (LSR)

6.48 The LSR determines the vibration levels or attenuation in the ground as a function of distance caused by an incoherent line source of unit force point impacts, with line source (train) orientated along the alignment. Thus, the basic quantity required for the determination of the LSR would be the vibration response caused by a unit point source impact, which is defined as the Point Source Response (PSR). Given that the PSR would be along the alignment, the LSR would follow directly by incoherent integration of the PSR values. However, the determination of the PSR for force point impacts along the alignment over the length of the alignment is neither practical nor affordable. For example, at underground sections, force impacting would have to be performed in numerous boreholes drilled to the depth of the alignment and closely spaced along the alignment. Thus, certain assumptions have been invoked, which allow one PSR to be taken as representative along the alignment near a building receiver and to be used in the determination of the LSR. These assumptions include:

· ground is layer-wise homogeneous;

· ground is transversely isotropic along the alignment over the length of the train; and

· ground is between the alignment segment and the vibration receivers at which the LSR is to be determined.

6.49 If the ground satisfies these assumptions rigorously, it would be acceptable to use one PSR in the determination of the LSR. In normal circumstances, deviation from the idealised assumptions of transverse isotropy and layer-wise homogeneity is not significant enough to warrant the time, expense and impracticality of impacting along the entire length of the alignment.

6.50 LSR has already been measured in Hong Kong at a number of locations, and the most relevant measured results (taking into account the ground type) were used for the calculations. The LSR has been referenced from the data adopted in the WIL EIA Study. Appropriate LSR has been selected accordingly with consideration of geological characteristics along the alignment, which is characterised by similar ground material to WIL. Table 6.6 above shows the LSR values adopted for assessment.

Other Factors

6.51 Other correction factors including BCF, BVR, CTN and SAF were adopted as that mentioned under the assessment methodology of TBM-induced ground-borne noise.

Calculation of Leq

6.52 The Leq values have been calculated using MoleRat, by the following procedures:

· Calculate the noise level from a full train at each of many locations at 10m intervals along the whole line

· Sum the energy from these levels and calculate the SEL level

· Calculate the Leq levels from

Leq = 10 log [10^{(SELlong + 10 log Vlong)/10} + 10^{(SELshort + 10 log Vshort)/10}] – 35.6

where

Vlong	Number of long haul train movements in the relevant 30 minute or 24 hour period, expressed as the average number of movements per hour: For Leq(30min): V = N(30min) x 2 (N = number of movements) For Leq(24hour): V = N(24hour) / 24 (N = number of movements)
Vshort	Number of short haul train movements in the relevant 30 minute or 24 hour period, expressed as the average number of movements per hour: For Leq(30min): V = N(30min) x 2 (N = number of movements) For Leq(24hour): V = N(24hour) / 24 (N = number of movements)

Ground-borne Noise Impact Assessment

Construction Phase

TBM Induced Ground-borne Noise

6.53 The tunnel will be constructed by TBM mainly in soft ground, but also in some rock or rock/soft ground border. The locations where TBM will be used are shown in Table 6.9.

Table 6.9 Chainages where TBM Operation will occur

From	To
115+930	117+385
117+485	119+850
122+490	123+540
124+910	125+330
136+780	137+760
137+968	140+380

6.54 The TBM-induced ground-borne noise levels were predicted, and the times of day when tunneling could be carried out whilst meeting the ANLs over specific sections of the Project were also determined, basing on the following assumptions:

· For the case where the tunnel will be in rock and the NSR is piled down to rock, the vibration path has been assumed to be horizontally across the rock and up the piles into the building;

· For the cases where the tunnel will be in soft ground or the NSR is not on piles, the vibration path has been assumed to be through the ground along a slant path to the nearest part of the NSR

6.55 The predicted TBM ground-borne noise levels at the GNSRs with the distances adopted in the calculation are shown in Table 6.10. Sample calculations are given in Appendix 6.7.

Table 6.10 Predicted Ground-borne Construction Noise levels due to TBM Operation

GBNSR No.	Location	Predicted Level^(1), dB(A)	Criterion, dB(A)			Acceptable Operating Times^(2)(5)	Calculated Distance^(4) (m)
		Leq (30min)	Leq (day)	Leq (evening)	Leq (night)
GN3	Yaumati Catholic Primary School (Hoi Wang Road)	62	60 (55 for exam)	55	-	D^(3), N	5
GN4	Block 9, Charming Garden	60	65	55	40	D	5
GN5	Tower 5 Phase 1 Park Avenue	71	65	55	40	D^(3)	6
GN6	Hing Wong Mansion	56	65	55	40	D	37
GN7	Tai Fung Building (Block F) Cosmopolitan Estates	65	65	55	40	D	36
GN8	Chung Yew Building	70	65	55	40	D^(3)	19
GN9	West Kowloon Disciplined Services Quarters Block 1	53	65	55	40	D, E	19
GN10	Fu Yun House, Fu Cheong Estate	52	65	55	40	D, E	15
GN12	SKH St. Mary's Church Mok Hing Yiu College	51	60 (55 for exam)	55	-	D, E, N	21
GN12a	Tack Ching Girls' Secondary School	29	60 (55 for exam)	55	-	D, E, N	40
GN13	Tower 6 Aqua Marine	36	65	55	40	D, E, N	21
GN14	HKIVE Haking Wong Waterfront Annex	53	60 (55 for exam)	55	-	D, E, N	35
GN14a	Lai Chi Kok Reception Centre	63	65	55	40	D	43
GN26	426A Tsang Uk Tsuen	42	65	55	35	D, E	23
GN27	431A Tsang Uk Tsuen	40	65	55	35	D, E	26
GN28	510B Nam Hing Lei	40	65	55	35	D, E	26
GN29	630 Sheung Tsuen	44	65	55	35	D, E	28
GN31	DD110 LOT 482, Wang Toi Shan	80	65	55	40	D^(3)	19
GN33	348 Tsat Sing Kong	59	65	50	35	D	27
GN34	349 Tsat Sing Kong	61	65	50	35	D	27
GN35	374 Chuk Yau Road	57	65	50	35	D	46
GN36	DD104 LOT 1786, Chuk Yau Road	43	65	50	35	D, E	31
GN37	DD104 LOT 1396, Yau Tam Mei Tsuen, Chuk Yau Road	40	65	50	35	D, E	29
GN37a	Chun Shin Road, Yau Tam Mei Tsuen	41	65	50	35	D, E	53
GN38	45 Wai Tsai Tsuen	46	65	50	35	D, E	33
GN38a	Petrus Avenue House 21 Phase 1 The Vineyard	42	65	50	35	D, E	33
GN38b	China Bible Seminary	41	60 (55 for exam)	50	35	D, E	29
GN39	62D Wai Tsai Tsuen	49	65	50	35	D, E	34
GN40	House 1, Green Crest	50	65	50	35	D, E	42
GN41	House A73 Maple Gardens	56	65	50	35	D	39
GN42	House A78 Maple Gardens	47	65	50	35	D, E	38
GN43	Area Zoned as R(A)	34	65	50	35	D, E, N	31
GN44	House 5 Phase A Royal Palms	32	65	50	35	D, E, N	51
GN45	Village house in Mai Po	39	65	50	35	D, E	32

Notes:

(1) Bold and underlined figure indicates the predicted level exceed the daytime noise criterion of EIAO-TM.

(2) D = All days during daytime (0700 – 1900 hours) except general holidays (including Sundays), E = All days during evening period (1900 – 2300 hours), and general holidays (including Sundays) during the daytime and evening, N = All days during night-time period (2300 – 0700 hours).

(3) Ground-borne noise monitoring would be required to monitor the ground-borne noise impact induced by the TBM operation.

(4) The calculated distance is the minimum distance from the centre line of the nearest tunnel to the nearest part of the structure, including piles. It is mostly a slant distance, the exception being when the nearest point of the piles is at the same level as the tunnel (in which case the distance is a horizontal distance).

(5) Evening and night-time operation of TBM presented in the table is for indication of acceptable operating time only. TBM operation during restricted hours is subject to approval of CNP application.

6.56 According to the predicted ground-borne noise levels, as shown in Table 6.10, four NSRs would be subject to ground-borne noise levels exceeding the daytime noise limit of 65dB(A), due to TBM operation. The levels, however, are predicted based on a conservative assumption of good coupling between TBM operating in rock condition and building foundation (i.e. BCF is zero and the ground between has no discontinuities) and a safety factor. In practice, the safety factor may not be necessary and the good coupling may not occur at all locations. Lower levels may result at many locations, and the predicted levels may be taken as the upper end of the likely range to be expected.

6.57 Monitoring at the time of TBM operation will therefore be required to confirm and monitor the ground-borne noise levels. Where it is possible that the 65dB(A) limit will be exceeded, reducing the rotational speed and scheduling of the works in consultation with affected parties will be the available way of alleviating the impact. This action is required over the chainages shown in Table 6.11 at which exceedance of the daytime noise limit would be predicted.

Table 6.11 Locations at which TBM Ground-borne Noise Levels would Exceed the Daytime Noise Limit

NSR	Chainages where Levels Predicted to Exceed Daytime Criteria
	Track	From	To
GN3	Up	140+330	140+340
GN5	Up	140+840	140+860
GN8	Down	139+260	139+300
	Up	139+310	139+320
GN31	Up	123+480	123+500

6.58 Based on the daily progress of the TBM at LMC of 8-11m per day, it is likely that any exceedance of the criteria would extend for about two or three days at the affected NSRs.

PME Induced Ground-borne Noise

6.59 Table 6.12 shows a summary of the PME-induced ground-borne noise levels during the construction of adits. Sample calculations are given in Appendix 6.7

Table 6.12 Predicted PME Ground-borne Noise Levels during Construction

NSR	Construction Site	Operation	Leq(30min), dB(A)	Daytime Criteria, dB(A)
GN12a	Nam Cheong Shaft	Hydraulic breaker	44	60
GN14a	Drill & Blast Tunnel	Drill Rig	62	65
GN14b	Mei Lai Road Adit	Hydraulic breaker	<20	65
GN14c	Mai Lai Road Adit	Hydraulic breaker	59	60
GN15	Drill & Blast Tunnel	Drill Rig	<20	65
GN16	Drill & Blast Tunnel	Drill Rig	31	65
GN17	Drill & Blast Tunnel	Drill Rig	25	65
GN18	Drill & Blast Tunnel	Drill Rig	41	65
GN18a	Kwai Chung Adit	Hydraulic breaker	21	65
GN19	Drill & Blast Tunnel	Drill Rig	56	65
GN20	Drill & Blast Tunnel	Drill Rig	58	65
GN21	Drill & Blast Tunnel	Drill Rig	<20	65
GN21a	Shek Yam Adit	Hydraulic breaker	<20	65
GN22	Drill & Blast Tunnel	Drill Rig	<20	65
GN22a	Shek Yam Adit	Hydraulic breaker	<20	65
GN23	Drill & Blast Tunnel	Drill Rig	<20	65
GN24	Drill & Blast Tunnel	Drill Rig	56	65
GN25	Drill & Blast Tunnel	Drill Rig	46	60
GN25a	Pat Heung Adit	Drill Rig	<20	65
GN30	ERS Structure	Pile Rig	<20	65
GN35	Drill & Blast Tunnel	Drill Rig	<20	65

6.60 Predicted results indicate that all PME induced ground-borne noise levels comply with the daytime criteria.

Cumulative Construction Ground-borne Noise Impact

6.61 It is anticipated that there would be no cumulative construction ground-borne noise impact at GBNSR 14a due to TBM and PME operation, given that TBM and PME would not be operating simultaneously due to safety reason. For GBNSR 12a, the cumulative ground-borne noise level is 44dB(A), which complies with EIAO-TM, and therefore no adverse cumulative ground-borne noise impact is anticipated.

Operation Phase

6.62 Operational ground-borne noise levels were calculated by incorporating the algorithms discussed in a 3-D model, MoleRat, which is developed by Wilkinson Murray Limited. Leq_(30min) for day and night, Leq(24hr) and Lmax levels were calculated at most affected floor levels and the noise impact has been quantified by indicating the total number of dwellings or other sensitive elements exposed to levels exceeding the criteria.

Operational Information

6.63 Two train types are expected to operate for the Project; a long haul train of length 427m and a short haul train of length 214m.

6.64 As a worst case, the number of through train movements has been assumed to be the operational capacity of the system at daytime and evening (0700 – 2300 hours) and an equivalent hourly number for the two operational hours at night-time (2300 – 2400 and 0600 – 0700 hours), as shown in Table 6.13. In addition to this, there will be shunting movements between SSS and WKT during the operational hours, and these need to be added to allow calculation of total ground-borne noise levels. However, since no speed profiles are available for shunting trains, a conservative approach has been adopted whereby the shunting trains are assumed to travel the full length of the project.

Table 6.13 Assumed Train Movements

Track	Train Type	Movements per Hour
		Long Haul Train^(1)		Short Haul Train^(1)		Total
		Daytime and evening	Night-time	Daytime and evening	Night-time	24 Hour^(2)
Northbound	Short	13	6	0	3	6
	Long	2	0	2	1	2
	Total	15	6	2	4	8
Southbound	Short	12	5	1	0	6
	Long	3	0	3	0	2
	Total	15	5	4	0	8

Notes:

(1) Long haul and short haul trains will be operated during the period of 0600 – 2400 hours only.

(2) Train frequency for 24 hours was calculated based on the average hour of total 24-hour train movements.

6.65 The worst hours for through trains and shunting trains at night are not the same. The worst hour for through trains is 0600 - 0700 hours and for shunting trains is 2300 – 2400 hours. Nevertheless, the worst hours were added in a conservative approach. Where 30 minute train movements were required, these were derived by dividing the hourly movements by two.

6.66 The speed profiles adopted in the present assessment are presented in Appendix 6.8.

6.67 Turnouts of the inclined type have been assumed at the locations in Table 6.14.

Table 6.14 Locations of Turnouts

Up	Down
117+320	117+310
117+510	117+500
121+895	121+635
123+510	123+545
124+375	124+310
124+925	124+910
126+195	126+060
126+215	126+320
131+945	131+810
131+965	132+075
137+830	137+800
137+980	137+950
140+735	140+775
140+790	140+830
140+845	140+895
140+910	140+940
140+955	140+995
141+010	141+055
141+055	141+115
141+130	141+140
141+180	141+180

Predicted Ground-borne Noise Levels

6.68 The predicted ground-borne noise levels as a result of Project operation at the lowest occupied floor of GBNSRs, together with the distances used in the calculation are shown in Table 6.15. The calculation of the noise levels assumes the following conditions:

· For the case where the tunnel will be in rock and the NSR is piled down to rock, the vibration path has been assumed to be across the rock and up the piles into the building

· For the cases where the tunnel will be in soft ground, the NSR is not on piles or the NSR is on piles not down to rock, the vibration path has been assumed to be through the ground along a slant path to the nearest part of the NSR or piles.

· Where piling details are not known and the tunnel will be in rock, it has been assumed that the piles are down to rock (worst case assumption).

Table 6.15 Predicted Ground-borne Railway Noise Levels

GBNSR No.	Location	Predicted Ground-borne Noise Level, dB(A)				Criterion, dB(A)		Down Track Calculated Distance (m)	Up Track Calculated Distance (m)
		Leq, 30min (day)	Leq, 30min (night)	Leq (24hr)	Lmax	Leq, 30min (day)	Leq, 30min (night)
GN1	Future Development at West Kowloon Cultural District	25	20	22	36	N.A.	N.A.	20	20
GN2	Future Development at West Kowloon Cultural District	<15	<15	<15	21	N.A.	N.A.	40	40
GN2a	WKT Topside Development	38	34	36	48	55	45	27	27
GN2b	WKT Topside Development	39	34	37	48	55	45	27	27
GN2c	WKT Topside Development	41	36	39	50	55	45	27	27
GN2d	Block 6 Phase 1 Sorrento	<15	<15	<15	18	55	45	52	42
GN2e	Man King Building	<15	<15	<15	18	55	45	59	67
GN3	Yaumati Catholic Primary School (Hoi Wang Road)	28	23	26	40	55	45	15	5
GN4	Block 9, Charming Garden	26	21	24	38	55	45	5	15
GN5	Tower 5 Phase 1 Park Avenue	24	19	22	37	55	45	22	6
GN6	Hing Wong Mansion	<15	<15	<15	25	55	45	37	37
GN7	Tai Fung Building (Block F) Cosmopolitan Estates	19	<15	16	31	55	45	36	36
GN8	Chung Yew Building	22	17	20	35	55	45	19	19
GN9	West Kowloon Disciplined Services Quarters Block 1	17	<15	15	32	55	45	19	36
GN10	Fu Yun House, Fu Cheong Estate	23	18	21	39	55	45	15	30
GN11	Planned Nam Cheong Station Properties Development	29	24	27	43	55	45	7	9
GN11a^(2)	Planned Residential Development in Site 6	41	36	39	56	55	45	26	10
GN12	SKH St. Mary's Church Mok Hing Yiu College	20	15	18	35	55	45	36	21
GN12a	Tack Ching Girls' Secondary School	<15	<15	<15	24	55	45	40	56
GN13	Tower 6 Aqua Marine	<15	<15	<15	21	55	45	21	37
GN14	HKIVE Haking Wong Waterfront Annex	<15	<15	<15	29	55	45	35	41
GN14a	Lai Chi Kok Reception Centre	26	21	24	39	55	45	44	43
GN14b	Ward A, Lai Chi Kok Hospital	<15	<15	<15	25	55	45	101	90
GN15	40A Cheung Hang Village	<15	<15	<15	<15	50	40	235	235
GN16	Tower 6 Regency Park	<15	<15	<15	<15	55	45	250	248
GN17	Block 21 Wonderland Villas	<15	<15	<15	<15	55	45	275	275
GN18	Block 2 Greenknoll Court	<15	<15	<15	27	55	45	89	89
GN18b	Kwai Ying Building	25	20	23	38	55	45	57	61
GN19	Tower B Kwai Sing Centre	29	24	27	43	55	45	41	42
GN19a	Ming Tak Building	28	23	26	42	55	45	45	48
GN20	Block B Hutchison Estate	30	25	27	43	55	45	34	36
GN21	184 Yau Ma Hom Resite Village	15	<15	<15	28	55	45	73	73
GN22	18 Da Chuen Ping Village	<15	<15	<15	28	50	40	87	87
GN23	35 Sheung Kwai Chung Village	<15	<15	<15	<15	50	40	98	98
GN24	Sau Shan House, Cheung Shan Estate	<15	<15	<15	<15	55	45	125	124
GN25	Tsuen Wan Lutheran School	<15	<15	<15	<15	55	45	124	124
GN26	426A Tsang Uk Tsuen	<15	<15	<15	29	50	40	26	23
GN27	431A Tsang Uk Tsuen	<15	<15	<15	26	50	40	27	26
GN28	510B Nam Hing Lei	<15	<15	<15	25	50	40	26	29
GN29	630 Sheung Tsuen	17	<15	15	33	50	40	28	42
GN30	51A Leung Uk Tsuen	<15	<15	<15	<15	55	45	113	132
GN30a	Village Zone West Boundary, Leung Uk Tsuen	<15	<15	<15	<15	55	45	61	79
GN30b	Village house in Leung Uk Tsuen	<15	<15	<15	21	55	45	46	64
GN31	DD110 LOT 482, Wang Toi Shan	30	25	28	45	55	45	35	19
GN33	348 Tsat Sing Kong	21	16	19	34	50	40	29	27
GN34	349 Tsat Sing Kong	21	15	18	33	50	40	27	34
GN35	374 Chuk Yau Road	<15	<15	<15	27	50	40	46	52
GN36	DD104 LOT 1786, Chuk Yau Road	20	15	18	34	50	40	31	33
GN37	DD104 LOT 1396, Yau Tam Mei Tsuen, Chuk Yau Road	21	16	19	35	50	40	30	29
GN37a	Chun Shin Road, Yau Tam Mei Tsuen	<15	<15	<15	18	50	40	67	53
GN38	45 Wai Tsai Tsuen	20	15	18	34	50	40	33	33
GN38a	Petrus Avenue House 21 Phase 1 The Vineyard	<15	<15	<15	30	50	40	33	41
GN38b	China Bible Seminary	17	<15	15	31	50	40	33	29
GN39	62D Wai Tsai Tsuen	15	<15	<15	29	50	40	34	34
GN40	House 1, Green Crest	<15	<15	<15	24	50	40	53	42
GN41	House A73 Maple Gardens	<15	<15	<15	28	50	40	42	39
GN42	House A78 Maple Gardens	<15	<15	<15	25	50	40	38	40
GN43	Area Zoned as R(A)	20	15	18	34	50	40	31	32
GN44	House 5 Phase A Royal Palms	<15	<15	<15	15	50	40	65	51
GN45	Village house in Mai Po	19	<15	17	34	50	40	36	32

Note:

(1) Locations GN2a to GN2c are the locations of future WKT topside developments which are directly connected to the WKT by the station structure. The distances shown are therefore distances through the structure and not through the ground.

(2) Layout and foundation design of the future development at Site 6 were not available at the time of reporting. The potential ground-borne noise impact at the planned NSR was predicted by assuming that the worst affected noise sensitive use would be located at a minimum distance of 3m away from the outer surface of the tunnel box (10m from track), which is the boundary of the non-building/structural clearance zone. On-going liaison with Housing Department will be carried out in detailed design stage such that the future residential development at Site 6 would not be adversely affected by railway ground-borne noise. The Project Proponent will continue to liaise with the owner of Site 6, i.e. Hong Kong Housing Authority to resolve any interface issues between these two development projects. Based on the outcome of the liaison process, the trackform design and mitigation measures proposal will be reviewed if needed.

6.69 All of the predicted levels at existing residential receivers and at possible CDA developments over WKT are well below the criteria, generally as a result of deep underground alignment. Appendix 6.9 shows the sample calculation of selected GBNSRs.

6.70 Within the proposed West Kowloon Cultural District (WKCD) (locations GN1 and GN2), noise levels have been predicted at 20m and 40m from the nearest track to give an indication of the implications on any future development. The feasibility of providing upgraded trackform at WKT to minimise the potential ground-borne noise impact at WKCD has been investigated.

6.71 It is unlikely that FDL values will be higher than assumed for this analysis due to deterioration of rails and rolling stock, with the implementation of good maintenance regimes such that the Project will operate properly.

Recommended Mitigation Measures

Construction Phase

6.72 The predicted construction ground-borne noise levels will comply with the stipulated noise criteria at all NSRs, except four NSRs in proximity to TBM operation. Based on the daily progress of the TBM at LMC of 8-11m per day, it is likely that any exceedance of the criteria will be for about only two or three days. The operation of TBM during restricted hours will be subject to the control of CNP under NCO.

6.73 Monitoring at the time of TBM operation is recommended to confirm and monitor the ground-borne noise levels. An EM&A programme, together with careful scheduling of the works and close liaison with affected parties which would have exceedance of the noise criterion, is recommended to minimise the impact from the operation of TBM.

Operation Phase

6.74 With the predicted operation ground-borne noise levels complying with the stipulated noise criteria at existing NSRs, mitigation measures are not required during operation phase. Concerning the potential ground-borne noise impact due to the uncertainty of the FDL and LSR values, installation of low noise trackform at the concerned areas has been proposed and would be implemented to further minimise the ground-borne noise levels. Low noise trackform suitable for high speed railway includes isolated slab trackform (IST) and Vanguard. The insertion loss values for this trackform are shown in Appendix 6.10. The locations along the alignment where the predicted noise levels at the GBNSRs are comparatively high among other GBNSRs have been identified and the approximate chainages as presented in Table 6.16 will be provided with low noise trackform, where practicable.

6.75 In addition, to minimise the noise impact to the future WKCD, low noise trackform will also be provided at WKT. With the provision of low noise trackform at WKT, the L_max levels at areas within the WKCD site and outside the WKT boundary were predicted to be in general lower than 25dB(A).

6.76 The noise levels at the representative GBNSRs would be reduced to those shown in Table 6.17 with the provision of low noise trackform. Appendix 6.11 shows the sample calculation of selected GBNSRs with the provision of IST.

Table 6.16 Approximate Chainages where Low Noise Trackform to be provided

Southbound
From	To
123+040	123+640
133+160	133+660
137+600	138+350
139+100	139+600
140+900	141+600
Northbound
From	To
123+050	123+650
133+170	133+670
137+620	138+370
139+120	139+620
140+900	141+600

Table 6.17 Predicted Ground-borne Noise Levels with the Provision of IST

GBNSR No.	Location	Predicted Ground-borne Noise Level, dB(A)				Criterion, dB(A)		Down Track Calculated Distance (m)	Up Track Calculated Distance (m)
		Leq, 30min (day)	Leq, 30min (night)	Leq (24hr)	Lmax	Leq, 30min (day)	Leq, 30min (night)
GN1	Future Development at West Kowloon Cultural District	<15	<15	<15	23	N.A.	N.A.	20	20
GN2	Future Development at West Kowloon Cultural District	<15	<15	<15	<15	N.A.	N.A.	40	40
GN2a	WKT Topside Development^(1)	27	23	25	34	55	45	27	27
GN2b	WKT Topside Development^(1)	27	23	25	32	55	45	27	27
GN2c	WKT Topside Development^(1)	29	24	27	35	55	45	27	27
GN2d	Block 6 Phase 1 Sorrento	<15	<15	<15	<15	55	45	52	42
GN2e	Man King Building	<15	<15	<15	17	55	45	59	67
GN3	Yaumati Catholic Primary School (Hoi Wang Road)	28	23	26	40	55	45	15	5
GN4	Block 9, Charming Garden	26	21	24	38	55	45	5	15
GN5	Tower 5 Phase 1 Park Avenue	24	19	22	37	55	45	22	6
GN6	Hing Wong Mansion	<15	<15	<15	<15	55	45	37	37
GN7	Tai Fung Building (Block F) Cosmopolitan Estates	<15	<15	<15	17	55	45	36	36
GN8	Chung Yew Building	<15	<15	<15	24	55	45	19	19
GN9	West Kowloon Disciplined Services Quarters Block 1	17	<15	<15	32	55	45	19	36
GN10	Fu Yun House, Fu Cheong Estate	23	18	21	39	55	45	15	30
GN11	Planned Nam Cheong Station Properties Development	19	<15	17	34	55	45	7	9
GN11a^(2)	Planned Residential Development in Site 6	29	25	27	44	55	45	26	10
GN12	SKH St. Mary's Church Mok Hing Yiu College	19	<15	17	34	55	45	36	21
GN12a	Tack Ching Girls' Secondary School	<15	<15	<15	22	55	45	40	56
GN13	Tower 6 Aqua Marine	<15	<15	<15	21	55	45	21	37
GN14	HKIVE Haking Wong Waterfront Annex	<15	<15	<15	29	55	45	35	41
GN14a	Lai Chi Kok Reception Centre	26	21	24	39	55	45	44	43
GN14b	Ward A, Lai Chi Kok Hospital	<15	<15	<15	25	55	45	101	90
GN15	40A Cheung Hang Village	<15	<15	<15	<15	50	40	235	235
GN16	Tower 6 Regency Park	<15	<15	<15	<15	55	45	250	248
GN17	Block 21 Wonderland Villas	<15	<15	<15	<15	55	45	275	275
GN18	Block 2 Greenknoll Court	<15	<15	<15	27	55	45	89	89
GN18b	Kwai Ying Building	23	18	21	37	55	45	57	61
GN19	Tower B Kwai Sing Centre	21	16	19	33	55	45	41	42
GN19a	Ming Tak Building	21	16	19	30	55	45	45	48
GN20	Block B Hutchison Estate	23	18	20	35	55	45	34	36
GN21	184 Yau Ma Hom Resite Village	15	<15	<15	28	55	45	73	73
GN22	18 Da Chuen Ping Village	<15	<15	<15	28	50	40	87	87
GN23	35 Sheung Kwai Chung Village	<15	<15	<15	<15	50	40	98	98
GN24	Sau Shan House, Cheung Shan Estate	<15	<15	<15	<15	55	45	125	124
GN25	Tsuen Wan Lutheran School	<15	<15	<15	<15	55	45	124	124
GN26	426A Tsang Uk Tsuen	<15	<15	<15	29	50	40	26	23
GN27	431A Tsang Uk Tsuen	<15	<15	<15	26	50	40	27	26
GN28	510B Nam Hing Lei	<15	<15	<15	25	50	40	26	29
GN29	630 Sheung Tsuen	17	<15	15	33	50	40	28	42
GN30	51A Leung Uk Tsuen	<15	<15	<15	<15	55	45	113	132
GN30a	Village Zone West Boundary, Leung Uk Tsuen	<15	<15	<15	<15	55	45	61	79
GN30b	Village house in Leung Uk Tsuen	<15	<15	<15	21	55	45	46	64
GN31	DD110 LOT 482, Wang Toi Shan	18	<15	16	32	55	45	35	19
GN33	348 Tsat Sing Kong	20	15	18	34	50	40	29	27
GN34	349 Tsat Sing Kong	20	15	18	33	50	40	27	34
GN35	374 Chuk Yau Road	<15	<15	<15	27	50	40	46	52
GN36	DD104 LOT 1786, Chuk Yau Road	20	15	18	34	50	40	31	33
GN37	DD104 LOT 1396, Yau Tam Mei Tsuen, Chuk Yau Road	21	16	19	35	50	40	30	29
GN37a	Chun Shin Road, Yau Tam Mei Tsuen	<15	<15	<15	18	50	40	67	53
GN38	45 Wai Tsai Tsuen	20	15	18	34	50	40	33	33
GN38a	Petrus Avenue House 21 Phase 1 The Vineyard	<15	<15	<15	30	50	40	33	41
GN38b	China Bible Seminary	17	<15	15	31	50	40	33	29
GN39	62D Wai Tsai Tsuen	15	<15	<15	29	50	40	34	34
GN40	House 1, Green Crest	<15	<15	<15	24	50	40	53	42
GN41	House A73 Maple Gardens	<15	<15	<15	28	50	40	42	39
GN42	House A78 Maple Gardens	<15	<15	<15	25	50	40	38	40
GN43	Area Zoned as R(A)	20	15	18	34	50	40	31	32
GN44	House 5 Phase A Royal Palms	<15	<15	<15	15	50	40	65	51
GN45	Village house in Mai Po	19	<15	17	34	50	40	36	32

Note:

(1) Locations GN2a to GN2c are the locations of future WKT topside developments which are directly connected to the WKT by the station structure. The distances shown are therefore distances through the structure and not through the ground.

(2) Layout and foundation design of the future development at Site 6 were not available at the time of reporting. The potential ground-borne noise impact at the planned NSR was predicted by assuming that the worst affected noise sensitive use would be located at a minimum distance of 3m away from the outer surface of the tunnel box (10m from track), which is the boundary of the non-building/structural clearance zone. The Project Proponent will continue to liaise with the owner of Site 6, i.e. Hong Kong Housing Authority to resolve any interface issues between these two development projects. Based on the outcome of the liaison process, the trackform design and mitigation measures proposal will be reviewed if needed.

Cumulative Effect from Other Rail Lines

6.77 The Project will run close to other existing rail lines and the cumulative effect from other rail lines has been reviewed. Locations where other rail lines are relatively close are as follows:

· The WKT will be located in the vicinity of the KSL Austin Station

· The XRL will be parallel to KSL and reasonably close just north of WKT, and also parallel to, but further away, Tung Chung Line (TCL) and Airport Express Line (AEL)

· The XRL will pass close to the Tung Chung Line (TCL) Nam Cheong station

· The XRL will pass under the Tsuen Wan Line (TWL) at Lai Chi Kok

6.78 Any cumulative effect from KSL would relate to West Kowloon Cultural District. Whilst predicted noise levels L_max at GN1 and GN2, which are located at approx. 31m and 47m from the tracks at WKT, are less than 23dB(A), KSL would be at least 150m from any potential cultural development. At this distance low ground-borne noise levels are expected. As such cumulative impact from the Project and KSL is not anticipated.

6.79 Just north of WKT where the Project will be parallel to KSL, TCL and AEL, there are no GBNSRs located in proximity to these rail lines. Any cumulative effect is therefore considered irrelevant. At the point where XRL diverges from the other lines, GBNSR GN3 is 30m from the nearest XRL track and approximately 135m from KSL and further from the other lines. Given that the level predicted for GN3 is 28dB(A) L_eq,day, it is unlikely that other rail lines would increase the Leq levels at GBNSRs.

6.80 The nearest GBNSR near TCL Nam Cheong station and the project alignment is GN11a With the predicted ground-borne noise level of up to 25dB(A) L_eq,night at GN11a, the cumulative noise levels are therefore unlikely to be over the criteria, in particular TCL trains would slow down and stop at Nam Cheong station.

6.81 In Lai Chi Kok, the tracks will pass close to the TWL tracks. At the intersection, the nearest GBNSR is GN14a at a distance from XRL of 39m. However, this GBNSR is 100m from TWL and it is anticipated that the Leq levels from TWL would be low, especially considering the fact that the intersection is near Lai Chi Kok station and MTR trains would be at low speed. Therefore, the operation of TWL would therefore not add significantly to the ground-borne noise level of less than 21dB(A) Leq,night at GN14a, as predicted from XRL to the extent of making the cumulative levels up towards the criteria.

Environmental Monitoring and Audit

Construction Phase

6.82 The predicted ground-borne noise levels comply with the stipulated daytime noise criteria, except at a few sensitive receivers, where TBM operation would induce noise levels exceeding the noise criteria of 65 dB(A). Monitoring at the time of TBM operation is recommended to confirm and monitor the ground-borne noise levels.

6.83 Prior to the final design of the trackform and the extent of each type of trackform, and after the proposed train in operation outside Hong Kong, tests of the FDL of the train will be carried out to update the ground-borne noise prediction and the recommendation on mitigation measures as necessary.

6.84 The vibration borehole testing will be carried out at two carefully selected locations along the proposed tunnel alignment prior to the commencement of construction works to determine the LSR values under certain geological conditions. This will also allow updating of the ground-borne noise predictions and the recommendation on mitigation measures as necessary.

6.85 The construction stage of the Project could also be used to improve knowledge of the ground vibration conditions. During use of the TBM, the vibration levels in surrounding buildings will be measured. By also measuring the FDL of the TBM, the LSR values for some additional sections of the tunnel will be determined. This may allow further update of the ground-borne noise level predictions and, if necessary, a refinement of the trackform design.

6.86 An Environmental Monitoring and Audit (EM&A) programme is recommended to be developed with details of the EM&A requirements are provided in a stand-alone EM&A Manual.

Operation Phase

6.87 Prior to the operation phase of the Project, a commissioning test should be conducted to ensure compliance of the operational ground-borne noise levels with the EIAO-TM noise criteria. Details of the test requirements are provided in a stand-alone EM&A Manual.

Conclusion

Construction Phase

6.88 Construction ground-borne noise assessment has been conducted to assess the feasibility of TBM tunnelling construction. Prediction results indicated the TBM and PME induced ground-borne levels at GBNSRs comply with the EIAO noise limit, except exceedance predicted at four sensitive receivers due to TBM operation. It is however anticipated that the period of exceedance would be about only two or three days, basing on the TBM daily progress in LMC. An EM&A programme and scheduling of works, is recommended to control and monitor the construction ground-borne level. It is considered that TBM tunnel construction method would be feasible for the tunnel construction but the operation of TBM during restricted hours should be governed by the control of CNP under NCO.

Operation Phase

6.89 Ground-borne noise levels have been predicted based on the maximum operation capacity of railway system. Assessment results indicated that the predicted ground-borne noise levels at the GBNSRs generally comply with the stipulated EIAO-TM noise criteria, and thus no special trackform will be required to meet the criteria. Low noise trackform will however be installed at the selected alignment sections to account for the uncertainty of the FDL and LSR values.

6.90 Low noise trackform will also be installed to minimise the impact on future development at WKCD. The Lmax levels at areas within the WKCD site and outside the WKT boundary will be reduced to levels lower than 25dB(A) in general with the provision of low noise trackform.

6.91 With the predicted low ground-borne noise levels at the GBNSRs, it is anticipated that there would be no cumulative effect from other rail lines, including KSL, TCL, AEL and TWL.

---

[1] Transit Noise and Vibration Impact Assessment. Report No. FTA-VA-90-1003-06

[2] Register No.: AEIAR-083/2005, KSL GSA 5100 Environmental Impact Assessment & Associated Services - Environmental Impact Assessment Report

[3] P. M. Nelson. Transportation Noise Reference Book. 1987.

[4] Final Report of High-Speed Ground Transportation Noise and Vibration Impact Assessment, HMMH Report No. 293630-4