sydney-city-centre-review-of-environmental-factors

The locations where these activities would take place are described Tables 3-3 to 3-7
and Table 3-11. Haulage would occur between the sources of the materials (refer
section 3.3.7), the work sites and the construction compound/laydown locations
described in section 3.5.1. Loading and unloading would occur at each work site and
the construction compound and laydown locations.
The impact of an accidental spillage would depend on the location of the spillage, the
type and quantity of materials spilt and the surrounding land conditions. The risks
would be greatest next to open drains, which are located adjacent to all the existing
roads within the proposal footprint. Spilt materials could potentially migrate to Sydney
Harbour or underlying groundwaters. The risk would be greatest next to open
excavations where drainage modifications and utility adjustments would take place
(refer to Table 3-11).
Sediment-laden runoff
Some of the proposed work detailed in section 3.3 would generate a small quantity of
spoil that has a potential to cause a water quality impact (refer to section 3.3.6). The
material may be highly erodible (refer to section 6.8.2). This introduces a risk and
potential for sediment-laden runoff to enter the trunk drainage system and
consequently impact on the water quality and values of Sydney Harbour. The risk
would be greatest during or immediately following heavy rainfall or as a result of
sweeping the roads as part of the general site maintenance (refer to section 6.7.4).
The corresponding activities within the proposal footprint that would be at greater risk
of sediment-laden runoff include any ground excavation work including utility
adjustments, drainage modifications, road furniture relocation, and general signage,
traffic signal and lighting pole relocations. Table 3-3 to Table 3-7 and Table 3-11
describe the location where these activities are planned to take place within the
proposal footprint.
Stockpile runoff
The only stockpiles associated with the proposal would be located within the
construction compound/laydown areas. These are established sites that will have
existing management processes and controls in place to manage associated
stockpile runoff. As described in section 3.3 there would only be a small quantity of
material that would need stockpiling under the proposal. Any stockpiled materials
would be generated as a result of the planned ground excavation work including
utility adjustments, drainage modifications, road furniture relocation, and general
signage, traffic signal and lighting pole relocations. Table 3-3 to Table 3-7 and
Table 3-14 describe the location where these activities are planned to take place
within the proposal footprint.
Ground/surface water contamination
Some of the proposed works detailed in section 3.3 would have the potential to affect
ground or surface water quality due to the potential to mobilise pollutants associated
with residual ground contamination. Again, the planned ground excavation work
described above would represent the activities with the greatest risk and potential of
encountering ground contamination.
There are two work sites within the proposal footprint that have a higher
contamination risk are: S4: Ultimo Road and S5: Broadway due to the area’s historic
land use and recorded presence of underlying manmade fill material (refer to
section 6.8.2).
Sydney City Centre Capacity Improvement 369
Review of Environmental Factors