3 AIR QUALITY

3.1 Introduction

3.1.1.1 The EIA study of this Project concluded that, with the implementation of the dust suppression measures stipulated in the Air Pollution Control (Construction Dust) Regulation, good site practices and proposed mitigation measures, adverse dust impact would not be anticipated at the Air Sensitive Receivers (ASRs) as shown in Figure 3.1 in the vicinity of the construction sites. As such, dust monitoring is not recommended.

3.1.1.2 However, weekly site audits are recommended to ensure that appropriate dust control measures are properly implemented and good construction site practices are adopted throughout the construction period.

3.1.1.3 Air quality monitoring during the operation phase of this Project is considered not necessary as the proposed Workshop would not expected to significant air quality impacts to the adjacent identified ASRs.

3.2 Air Sensitive Receivers

3.2.1.1 The existing ASRs assessed in the EIA study were identified with reference to the latest information provided on the survey maps, topographic maps, aerial photos, land status plans and confirmed by various site surveys undertaken. The planned ASR identified with reference to the latest published Chai Wan Outline Zoning Plan (OZP) No. S/H20/20 is an educational institute at the junction of Wing Tai Road and Shing Tai Road, Chai Wan which is located at the immediate vicinity of the western site boundary of the proposed EMSD Hong Kong Workshop and is known to have a height restriction of 70 mPD.

3.2.1.2 The relevant stakeholders have been approached as far as practicable so as to obtain the latest information on planning application, layout and building height, etc. The major planned uses in the vicinity of the area include different land uses including Commercial, comprehensive Development Area, Residential, Government, Institution or Community, Open Space and Other Specified Uses of Chai Wan Future Development.

3.2.1.3 With reference to Section 3.4.2.2 of EIA Study Brief, the study area for the air quality impact assessment should be defined by a distance of 500 metres from the boundary of the Project site. The assessment included the existing sensitive receivers within the study area, including Tsui Wan Estate, Hang Tsui Court, Hong Kong Institute of Vocational Education (Chai Wan), Chai Wan Industrial City (Phase II), as well as areas where air quality may be potentially affected by the Project. The construction phase of the proposed education institute will be tentatively from the third quarter in 2013 to the third quarter of 2016. The construction phase of the proposed institute will overlap with some periods (~a few months) of the construction phase of the proposed EMSD work shop, while the operation phase of the institute will overlap with approximate 10 months of the operation phase of the Workshop.

3.2.1.4 The existing ASRs are residential buildings, hospital, schools and educational institutions, industrial buildings, commercial buildings, parks and sitting-out areas in Chai Wan. There are no planned ASRs known as this stage. The details of the identified representative ASRs are summarised in Table 3.1.

Table 3.1 Representative Air Sensitive Receivers

ASR⁽¹⁾	Location	Landuse	Assessment Height (Above Ground Level)⁽²⁾	Building Height (m)⁽³⁾	Horizontal Distance to Project Site (m)
ASR 1	Hong Kong Institute of Vocational Education (Chai Wan)	Institution	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	17	197
ASR 2	Pamela Youde Nethersole Eastern Hospital, Barrack Block	Residential	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	28	253
ASR 3	Tsui Shou House, Tsui Wan Estate	Residential	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	87	47
ASR 4	Chai Wan Industrial City (Phase II)	Industrial	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	62	147
ASR 5	Tsui Ching House, Hang Tsui Court	Residential	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	98	192
ASR 6	Cornell Centre	Industrial	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	68	245
ASR 7	Chai Wan Faith Love Lutheran School	Institution	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	20	277
ASR 8	Chai Wan Fire Station	Government	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	14	310
ASR 9	Federal Centre	Industrial	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	62	312
ASR 10	Planned Educational Institute	Institution	(1.5m)/ (1.5m, 5m, 10m, 15m, 20m)	66⁽⁴⁾	0

(1) ASRs relevant to both the construction and operation phases of the Project.

(2) (1.5m)/(1/5m, 5m, etc) represent construction/operation phases respectively.

(3) The height of each storey of the buildings is assumed as 2.8m.

(4) According to the height restriction of 70 mPD from the OZP, the maximum height of the planned educational institute is assumed.

3.3 Mitigation Measures

3.3.1.1 The recommended mitigation measures for construction dust impacts are presented the EMIS in Appendix 1.1 of this EM&A Manual. In the event of complaints or non-compliances, the ET, Engineer and Contractor should review the effectiveness of these mitigation measures, design alternatives or additional mitigation measures as appropriate. The Contractor should propose the corrective action to the Engineer for approval, and implement them accordingly. These measures should include the following dust suppression measures stipulated in the Air Pollution Control (Construction Dust) Regulation and good site practices:

· Use of regular watering, to reduce dust emissions from exposed site surfaces and unpaved roads, particularly during dry weather;

· Use of frequent watering for particularly dusty construction areas and areas close to ASRs;

· Side enclosure and covering of any aggregate or dusty material storage piles to reduce emissions. Where this is not practicable owing to frequent usage, watering should be applied to aggregate fines;

· Open temporary stockpiles should be avoided or covered. Prevent placing dusty material storage piles near ASRs;

· Tarpaulin covering of all dusty vehicle loads transported to, from and between site locations;

· Establishment and use of vehicle wheel and body washing facilities at the exit points of the site;

· Imposition of speed controls for vehicles on unpaved site roads. 8km per hour is the recommended limit;

· Routing of vehicles and positioning of construction plant should be at the maximum possible distance from ASRs;

· Every stock of more than 20 bags of cement or dry pulverised fuel ash (PFA) should be covered entirely by impervious sheeting or placed in an area sheltered on the top and the 3 sides; and

· Loading, unloading, transfer, handling or storage of large amount of cement or dry PFA should be carried out in a totally enclosed system or facility, and any vent or exhaust should be fitted with an effective fabric filter or equivalent air pollution control system.

3.4 Audit Requirements

3.4.1.1 The implementation of regular site audits aims to ensure the mitigation measures recommended in the EIA report to be properly undertaken during the construction phase of this Project. It can also provide an effective control of any mal-practices and, therefore, achieve the continual improvement of the environmental performance on-site.

3.4.1.2 Inspections of the construction activities and works sites and works areas should be conducted by the Contractor at least on a weekly basis to ensure the mitigation measures to be properly implemented.

3.4.1.3 Site audits should be carried out by the Engineer, ET and Contractor, and should be based on the mitigation measures for the air pollution control as recommended in Appendix 1.1. In the event that the recommended mitigation measures are not fully or properly implemented, the Contractor should report the deficiency to the Engineer and ET. The appropriate action will need to be taken by the Contractor:

· Investigate the problems and causes;

· Discuss a remedial and corrective proposal with the ER and ET;

· Take action according to the action notes agreed with the ER;

· Implement the remedial and corrective action immediately;

· Re-inspect the site conditions upon the completion of the remedial and corrective action; and

· Record the event.