Dr. Samuel Chui, JP
Director of Environmental Protection
EIA Ordinance Register Office
Environmental Protection Department
(Email: eiaocomment@epd.gov.hk)
While Green Power appreciates the project proponent’s effort to adopt an option with lower overall environmental impacts (i.e. construction of an underground railway mostly using Tunnel Boring Machine (TBM) instead of viaducts or intensive usage of drill and blast methods which are more environmentally disturbing), we would like to provide the following comments on the captioned Environmental Impact Assessment (EIA) Report.
1. <u>Wetland Compensation and Management</u>
A compensation wetland located between the existing parcels of the West Rail Compensation Wetlands (WRCW) managed by MTRC and another proposed compensation wetland site under another development project is proposed in the EIA report. Although these current and future wetlands may form parts of a larger wetland system, the performance of such a system depends largely on how the wetlands are created and managed, and the difficulty of such cannot be underestimated. We would like to highlight the importance and difficulty of compensating for both the area and functions of the habitats to be lost, and that the feasibility of such proposal requires careful consideration.
The EIA report states that the compensation wetland of size 1.9 ha, which currently consists of 1.35 ha of marsh/reed and pond of low to moderate ecological value and 0.58 ha of dry habitat, will be managed to compensate for 1.02 ha of marsh/reed with moderate ecological value to be lost under the project. In terms of area, the proposed mitigation is only compensating for the loss of 1.02 ha of wetlands by converting 0.58 ha of dry habitats into artificial wetlands. In terms of function, the current WRCW have demonstrated that these artificial wetlands may not perform as expected nor have the same capacity to accommodate the target species (e.g. Greater Painted Snipe) as the wetlands they replaced. Several parcels of the WRCW are also only of low to moderate ecological value after many years of management. The fact that the overall future compensation wetlands in the area will ultimately be managed by two parties which do not have any planned collaboration further adds to the challenge of creating and managing the wetlands holistically.
We opine that the Environmental Permit (EP) should require the project proponent to mitigate both the area and function of the wetlands to be lost and clear ecological targets and details of creation and management shall be described with reference to the habitats to be lost in the Habitat Creation and Management Plan.
2. <u>Egretries and Ardeid Night Roosts</u>
The proximity of egretries and ardeid night roosts (ANR) to the above-ground works sites or areas and thus the potential impacts they receive under the proposed project require careful evaluation.
The Kam Po Road Egretry and ANR are only 60m from the nearest proposed above-ground works site, while the Sha Po ANR is less than 25m from the nearest proposed at-grade works site. Although the EIA report states that the works sites would only be used for minor works (road construction, utilities laying and reprovision of bicycle parking area near Kam Po Road Egretry and ANR) or non-disturbing function (material storage near Sha Po ANR) and assumes no or low to moderate adverse ecological impacts, noise and dust associated with the construction and/or increase in traffic and human flows would be unavoidable. It should also be noted that no flight path survey was done for Sha Po ANR under the EIA (see section 10.4.21 of the EIA report) and it is unknown whether the conversion of the nearby area into works sites would interfere with the ardeids’ behavior.
It is critical that the impacts on these sensitive receivers be properly assessed, and that details of the mitigation measures, including the application of noise barrier, phasing of works to avoid the breeding season (March to August) of ardeids, as well as the allowed working hours should be listed in the EP.
3. <u>Potential Risk on Above-ground Habitats Due to Underground Construction</u>
Although the proposal of adopting the TBM to construct the underground railway is said to avoid significant habitat loss above ground, we would like to emphasize the potential risks of structural damages and water pollution, including the structural subsidence of or even leakage of construction materials such as sludges into these above-ground aquatic habitats. This is of particular concern as these situations occurred in the important wetlands of Mai Po and Inner Deep Bay during the construction of the High Speed Rail (Hong Kong Section) in 2015, which caused water pollution and structural damages in fish ponds which are critical to resident and migratory water birds. As the proposed rail alignment of the current project passes through a lot of water-sensitive receivers including fishponds and rivers that are vulnerable to these risks, preventive measures and contingency plans regarding both subsidence and accidental leakage of materials above ground during tunnel boring should be included in the EIA report as well as the EP.
4. <u>Control of sewage discharge</u>
Discharge points and boundaries for treated sewage should be designated in a precautionary manner (i.e. avoidance of no-go areas at the beginning stage, including all ecologically sensitive areas and areas upstream of them). Efficiency of sewage treatment facilities should be ensured by regular checking and maintenance work, particularly during the wet season and before rainstorms. Monitoring of water quality parameters in water bodies near the construction sites (in addition to treated sewage discharge points) is an essential control measure. Any discharge points of surface runoff generated from the works sites and treated sewage should not be located at or in the vicinity of any freshwater or ecologically sensitive areas identified.
Chemicals and toxic substances should not be stored, left over or discarded in the works sites or any places that are prone to flooding or will generate surface runoff discharging into ecologically sensitive areas identified. Any leakage or spillage of bentonite to natural water bodies must be avoided and closely monitored.
5. <u>Illegal Dumping and Stockpiling</u>
The construction of above-ground structures as well as underground tunnels (whether by cut-and-cover method or TBM) produces a significant amount of C&D materials, which provide ample incentives and materials for illegal dumping activities in the area. Although the EIA report requires all dump trucks engaged in the project to be equipped with GPS or an equivalent system for tracking and monitoring their travel routes and parking locations, we opine that the EP should require explicitly that such terms be listed in all work contracts and that such system should be monitored in real-time using geofencing or other equivalent instant monitoring measures to alert of infringement of ecologically sensitive areas by the vehicles. It is also critical to maintain clear boundaries of all works sites and areas to avoid encroachment of stockpiled materials into ecologically sensitive areas.
Thank you very much for your kind attention. For any inquiries, please contact the undersigned at Green Power (Tel: 3961 0200, Fax: 2314 2661, Email: info@greenpower.org.hk).
Yours sincerely,
Yuen Yan Ling, Elaine
Conservation & Research Manager
Green Power
Yours sincerely,
Yuen Yan Ling, Elaine
Conservation & Research Manager
Green Power