Appendix A (as referred to in Condition 3.8)

Measures to Mitigate Environmental Impacts due to Site Run-off and Other Potential Water Pollution During Construction

(a) Surface Runoff

(i) Surface run-off from the construction site shall be directed into adequately designed sand/silt removal facilities such as sand traps, silt traps and sediment basins before discharge into storm drains. Channels, earth bunds or sand bag barriers shall be provided on site to properly direct stormwater to such silt removal facilities.

(ii) Catchpits and perimeter channels shall be constructed in advance of site formation works and earthworks.

(iii) Silt removal facilities, channels and manholes shall be maintained with the deposited silt and grit being removed at least once a week, and at the onset of and after each rainstorm to ensure that these facilities are functioning at all times.

(b) General Construction Activities

(iv) Materials which may cause contamination to the Water Gathering Grounds shall only be stored in the properly designed storage areas to prevent leakage, spillage and release of the materials. On-site storage of construction materials (e.g. aggregates and sand) shall be covered with tarpaulin or similar fabric during rainstorms. Measures such as providing sand bag barriers shall be taken to prevent the washing away of construction materials, soil, silt or debris into any drainage system.

(v) At all parts of all works areas and construction sites, and throughout the full duration of the construction contract(s), debris and rubbish on site shall be handled and disposed of to avoid entering the water column and causing water quality impacts. Temporary on-site storage of excavated materials shall be covered with tarpaulin or similar fabric during rainstorms. Any washout of construction or excavated materials should be diverted to the drainage system via sediment traps.

(vi) Soil excavation shall be minimized in rainy seasons. All excavated or filled surfaces shall be protected from erosion.

- end -