THE GOVERNMENT OF THE HONG KONG

SPECIAL ADMINISTRATIVE REGION

DRAINAGE SERVICES DEPARTMENT

 

 

 

 

 

 

 

 

 

 

Tolo Harbour Sewerage of Unsewered Areas, Stage II -

Investigation, Design and Construction

 

 

Sai O Trunk Sewer Sewage Pumping Station

 

 

 

 

 

 

 

Environmental Impact Assessment Report 

Volume I – Main Text

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AECOM Asia Co. Ltd.

 

March 2021


TABLE OF CONTENTS

1.              introduction.. 1-1

1.1......... Background. 1-1

1.2......... Purpose of the EIA Report 1-2

1.3......... Objectives of the EIA Report 1-2

1.4......... Structure of the Report 1-3

2.              Project description.. 2-1

2.1......... Project Location and Description. 2-1

2.2......... Need of the Project 2-2

2.3......... Consideration of Alternative Locations and Design Options. 2-3

2.4......... Considerations of Construction Methods and Sequences of Works. 2-12

2.5......... Selection of Preferred Scenario. 2-14

2.6......... Construction Programme. 2-14

2.7......... Concurrent Project 2-14

3.              air quality.. 3-1

3.1......... Introduction. 3-1

3.2......... Environmental Legislation, Standards and Guidelines. 3-1

3.3......... Description of the Environment and Future Trend. 3-2

3.4......... Identification of Pollution Sources. 3-5

3.5......... Assessment Methodology. 3-6

3.6......... Prediction and Evaluation of Environmental Impacts. 3-7

3.7......... Recommended Mitigation Measures. 3-9

3.8......... Evaluation of Residual Impacts. 3-10

3.9......... Environmental Monitoring and Audit 3-10

3.10....... Conclusion. 3-11

4.              NOISE.. 4-1

4.1......... Introduction. 4-1

4.2......... Environmental Legislation, Standards and Criteria. 4-1

4.3......... Description of the Environment 4-3

4.4......... Noise Sensitive Receivers. 4-3

4.5......... Identification of Environmental Impacts. 4-4

4.6......... Assessment Methodology. 4-5

4.7......... Prediction and Evaluation of Environmental Impacts. 4-6

4.8......... Mitigation of Adverse Environmental Impacts. 4-7

4.9......... Evaluation of Residual Impacts. 4-11

4.10....... Environmental Monitoring and Audit 4-11

4.11....... Conclusion. 4-12

5.              WATER QUALITY.. 5-1

5.1......... Introduction. 5-1

5.2......... Environmental Legislation, Standards and Guidelines. 5-1

5.3......... Description of Environment 5-4

5.4......... Water Sensitive Receivers. 5-10

5.5......... Assessment Methodology. 5-10

5.6......... Identification of Environmental Impacts. 5-10

5.7......... Evaluation of Environmental Impacts. 5-11

5.8......... Mitigation Measures. 5-16

5.9......... Residual Environmental Impacts. 5-19

5.10....... Environmental Monitoring and Audit 5-19

5.11....... Conclusion. 5-19

6.              waste management implications.. 6-1

6.1......... Introduction. 6-1

6.2......... Environmental Legislation, Standards and Guidelines. 6-1

6.3......... Assessment Methodology. 6-3

6.4......... Identification and Evaluation of Potential Impacts. 6-4

6.5......... Mitigation Measures. 6-7

6.6......... Evaluation of Residual Impacts. 6-10

6.7......... Environmental Audit 6-10

6.8......... Conclusion. 6-11

7.              Land contamination.. 7-1

7.1......... Introduction. 7-1

7.2......... Environmental Standards and Guidelines. 7-1

7.3......... Assessment Methodology. 7-1

7.4......... Description of the Environment 7-2

7.5......... Site Appraisal 7-2

7.6......... Prediction and Evaluation of Land Contamination Impacts. 7-3

7.7......... EM&A Requirements. 7-3

7.8......... Conclusion. 7-3

8.              ECOLOGY (Terrestrial and Aquatic) 8-1

8.1......... Introduction. 8-1

8.2......... Environmental Legislation, Standards and Guidelines. 8-1

8.3......... Assessment Methodology. 8-3

8.4......... Description of the Environment 8-6

8.5......... Ecological Value. 8-17

8.6......... Identification of Potential Impacts. 8-30

8.7......... Prediction and Evaluation of Environmental Impacts. 8-30

8.8......... Mitigation of Adverse Environmental Impacts. 8-40

8.9......... Evaluation of Residual Impacts. 8-41

8.10....... Environmental Monitoring and Audit 8-41

8.11....... Conclusion. 8-41

8.12....... Reference. 8-42

9.              Hazard to Life.. 9-1

9.1......... Introduction. 9-1

9.2......... Environmental Legislation, Standards and Guidelines. 9-3

9.3......... Population Data. 9-3

9.4......... Hazard Identification. 9-3

9.5......... Frequency Assessment 9-4

9.6......... Consequence Assessment 9-4

9.7......... Risk Assessment 9-4

9.8......... Conclusion. 9-5

10             Landscape and Visual Impact. 10-1

10.1....... Introduction. 10-1

10.2....... Environmental Legislation, Standards and Criteria. 10-1

10.3....... Assessment Methodology. 10-2

10.4....... Review of Planning and Development Control Framework. 10-6

10.5....... Baseline Study. 10-7

10.6....... Landscape Impact Assessment 10-13

10.7....... Visual Impact Assessment 10-16

10.8....... Landscape and Visual Mitigation Measures. 10-19

10.9....... Residual Impact 10-21

10.10..... Environmental Monitoring and Audit 10-28

10.11..... Conclusion. 10-28

11.            Cultural heritage impact. 11-1

11.1....... Introduction. 11-1

11.2....... Environmental Legislation, Standards and Guidelines. 11-1

11.3....... Assessment Methodology. 11-2

11.4....... Background Information. 11-3

11.5....... Baseline Condition. 11-7

11.6....... Review on Cultural Heritage Potential 11-9

11.7....... Impact Assessment 11-10

11.8....... Mitigation Measures. 11-10

11.9....... Environmental Monitoring and Audit 11-10

11.10..... Conclusion. 11-10

11.11..... Bibliography. 11-10

12.            environmental monitoring & audit requirements.. 12-1

12.1....... Introduction. 12-1

12.2....... Air Quality Impact 12-1

12.3....... Noise Impact 12-1

12.4....... Water Quality Impact 12-1

12.5....... Waste Management Implications. 12-2

12.6....... Land Contamination. 12-2

12.7....... Ecological Impact 12-2

12.8....... Hazard to Life. 12-2

12.9....... Landscape and Visual Impact 12-2

12.10..... Cultural Heritage Impact 12-3

13.            IMPLEMENTATION SCHEDULE OF THE PROPOSED MITIGATION MEASURES.. 13-1

14.            Summary of Environmental Outcomes. 14-1

14.1....... Overview.. 14-1

14.2....... Environmental Benefits of the Project 14-1

14.3....... Environmentally Friendly Designs Recommended. 14-1

14.4....... Key Environmental Problems Avoided and Compensation Area Included. 14-2

14.5....... Population and Environmentally Sensitive Areas Protected. 14-3

14.6....... Environmental Protection Measures Recommended. 14-3

15.            Conclusions.. 15-1

15.1....... Introduction. 15-1

15.2....... Air Quality. 15-1

15.3....... Noise. 15-2

15.4....... Water Quality. 15-2

15.5....... Waste Management Implications. 15-2

15.6....... Land Contamination. 15-2

15.7....... Ecology. 15-3

15.8....... Hazard to Life. 15-3

15.9....... Landscape and Visual 15-3

15.10..... Cultural Heritage. 15-4

15.11..... Overall Conclusion. 15-4

 

 

List of Tables

Table 2.1          Environmental Considerations for the Alternative Locations

Table 2.2          Comparison of Alternative Location Options

Table 3.1          Hong Kong Air Quality Objectives

Table 3.2          Summary of the Latest Available Five-Year Air Quality Data at Tai Po Air Quality Monitoring Station (2015 to 2019)

Table 3.3          Air Pollutants Concentrations in 2020 Predicted from PATH-2016 Model

Table 3.4          Representative Air Sensitive Receivers

Table 3.5          Predicted Maximum 5-second Average Odour Concentration at Representative Air Sensitive Receivers

Table 4.1          Daytime Construction Noise Criteria

Table 4.2          Area Sensitivity Ratings

Table 4.3          Acceptable Noise Level for Fixed Plant Noise

Table 4.4          Representative Noise Sensitive Receivers

Table 4.5          Summary of Predicted Construction Noise Levels without Mitigation Measures

Table 4.6          Summary of Predicted Fixed Plant Noise Levels without Mitigation Measures

Table 4.7          Proposed Quiet PME for the Project

Table 4.8          Predicted Construction Noise Levels at Representative Noise Sensitive Receivers – Mitigated Scenario

Table 4.9          Predicted Cumulative Construction Noise Levels at Representative Noise Sensitive Receivers – Mitigated Scenario

Table 4.10        Predicted Fixed Plant Noise Level with Mitigation Measures

Table 5.1          Summary of Water Quality Objectives for Tolo Harbour and Channel WCZ

Table 5.2          Summary Statistics of Marine Water Quality in Tolo Harbour and Channel WCZ (TM6 & TM7) in 2019

Table 5.3          Summary of Baseline Water Quality Survey Results

Table 6.1          Summary of Estimated Quantities of C&D Materials Generated during Construction of the Project

Table 6.2          Summary of Waste Handling Procedures and Disposal Routes

Table 7.1          Aerial Photographs Reviewed

Table 8.1          Size of Habitats Recorded within the Assessment Area

Table 8.2          Total Abundance and Biomass of Each Faunal Group

Table 8.3          Overall Abundance and Biomass Recorded from Each Sampling Site

Table 8.4          Physical Conditions of the Spot-check Dive Sites

Table 8.5          Species, Coverage, Size, Condition and Translocation Feasibility of Corals Found at the Spot-check Dive Sites

Table 8.6          Physical Conditions of the REA Transect

Table 8.7          Ecological and Substratum Attributes of REA1

Table 8.8          Size, Health Condition and Translocation Feasibility of Coral Colony Recorded at REA1

Table 8.9          Ecological Evaluation of the Project Site

Table 8.10        Ecological Evaluation of Woodland within the Assessment Area

Table 8.11        Ecological Evaluation of Mixed Woodland within the Assessment Area

Table 8.12        Ecological Evaluation of Plantation within the Assessment Area

Table 8.13        Ecological Evaluation of Shrubland within the Assessment Area

Table 8.14        Ecological Evaluation of Grassland within the Assessment Area

Table 8.15        Ecological Evaluation of Developed Area/Wasteland within the Assessment Area

Table 8.16        Ecological Evaluation of Modified Watercourse within the Assessment Area

Table 8.17        Ecological Evaluation of Natural Watercourse within the Assessment Area

Table 8.18        Ecological Evaluation of Seashore, Subtidal Hard Bottom Habitat and Subtidal Soft Bottom Habitat within the Assessment Area

Table 8.19        Floral and Faunal Species of Conservation Importance Recorded during Previous and Recent Ecological Surveys

Table 8.20        Evaluation of Ecological Impact to Woodland within the Assessment Area

Table 8.21        Evaluation of Ecological Impact to Mixed Woodland within the Assessment Area

Table 8.22        Evaluation of Ecological Impact to Plantation within the Assessment Area

Table 8.23        Evaluation of Ecological Impact to Shrubland within the Assessment Area

Table 8.24        Evaluation of Ecological Impact to Grassland within the Assessment Area

Table 8.25        Evaluation of Ecological Impact to Developed Area/Wasteland within the Assessment Area

Table 8.26        Evaluation of Ecological Impacts to Modified Watercourse and Natural Watercourse within the Assessment Area

Table 8.27        Evaluation of Ecological Impacts to Intertidal Habitats

Table 8.28        Evaluation of Ecological Impacts to Subtidal Hard Bottom Habitat and Subtidal Soft Bottom Habitat

Table 8.29        Summary of Potential Impacts to Species of Conservation Importance Recorded in the Assessment Area

Table 10.1        Relationship between Landscape Sensitivity and Magnitude of Change in Defining Impact Significance

Table 10.2        Relationship between VSRs Sensitivity and Magnitude of Change in Defining Impact Significance

Table 10.3        Summary of the Review of Planning and Development Control Framework

Table 10.4        Baseline LRs and their Sensitivity

Table 10.5        Baseline LCAs and their Sensitivity

Table 10.6        Baseline VSRs and their Sensitivity

Table 10.7        Magnitude of Landscape Impacts during Construction and Operation

Table 10.8        Magnitude of Visual Impacts during Construction and Operation

Table 10.9        Landscape and Visual Mitigation Measures for Construction Phase

Table 10.10      Landscape and Visual Mitigation Measures for Operational Phase

Table 10.11      Significance of Landscape Impacts during Construction and Operational Phases

Table 10.12      Significance of Visual Impacts during Construction and Operational Phases

Table 13.1        Implementation Schedule of the Proposed Mitigation Measures for Air Quality Impact

Table 13.2        Implementation Schedule of the Proposed Mitigation Measures for Noise Impact

Table 13.3        Implementation Schedule of the Proposed Mitigation Measures for Water Quality Impact

Table 13.4        Implementation Schedule of the Proposed Mitigation Measures for Waste Management Implications

Table 13.5        Implementation Schedule of the Proposed Mitigation Measures for Land Contamination Issues

Table 13.6        Implementation Schedule of the Proposed Mitigation Measures for Ecological Impact

Table 13.7        Implementation Schedule of the Proposed Mitigation Measures for Hazard to Life

Table 13.8        Implementation Schedule of the Proposed Mitigation Measures for Landscape and Visual Impact

Table 13.9        Implementation Schedule of the Proposed Mitigation Measures for Cultural Heritage Impact

Table 14.1        Key Recommended Mitigation Measures