TINTENBAR TO EWINGSDALECommunity information session No. 8Upcoming traffic changes and tunnel construction

28 August 2012

Mucking (removal of blast material)Current site compound access from Bangalow Road

Agenda

• Construction update/look ahead• Ancillary compounds update• Traffic management for local road upgrades

• Pacific Highway traffic staging at Bangalow• Bangalow Road traffic staging• Broken Head Road diversion

• Controlled environmental burning• Tunnel construction • Community involvement• Questions• Informal discussion with project team members.

Construction update

Construction activities undertaken over the past month include:•Bangalow site compound construction ongoing•Fence installation in plantation areas ongoing•Diversion drains at fish farm under construction•Installation of access gates off Pacific Highway at various locations•Property access works ongoing.

Diversion drain at old fish farm, Knockrow

Bangalow site compound establishment

• Earthworks have been completed.

• Pavement spray seal has been completed.

• All site offices have been installed.

• Utility services are being connected.

• Furniture installation has commenced.

• Offices will be operational as a site compound from September 2012.

Bangalow site compound construction August 2012

Fence installation ─ environmental protection

•Protective fencing has been installed around identified heritage items, environmentally sensitive areas and groundwater monitoring points. •Wherever possible, fence lines have been offset from the boundary to minimise the impact on the environment. •This type of fence installation will continue over the coming months.

Orange bunting protects ‘no-go’ zones

Fence installation ─ through plantations

• Clearing for boundary fencing lines has progressed in the central (area around Newrybar) and southern sections (area around Ross Lane) of the project.

• In most areas, additional clearing into the plantations has been carried out by the adjacent landowners to enable harvesting plant to turn. Clearing through macadamia plantations

Site access gates

Site access gates are being installed to provide safe points for equipment and machinery to access the site from the existing highway.

Access gate No 5 at Yarenbool Place, Newrybar

Property adjustment works

• These works are 50% complete with placement of roadbase, spray sealing and a concrete causeway yet to be built.

• Existing property access is being upgraded to provide agreed construction access to the project alignment in the central zone location.

• Installation of environmental controls and the placement of general fill is in progress.

Central site access works in progress

Construction look−ahead ─ other works

Other works planned for the next month include:•Complete demolition of two remaining properties•Continue fence installation, including adjacent to plantation areas•Continue clean water diversion drains•Continue property adjustment works (private driveways)•Continue access gate installation

Three months look−ahead:•Substantial construction will commence following approval of CEMP.•Local road upgrades including Martins Lane West, Ivy Lane, St Helena Road, and Tinderbox Road.Tinderbox Valley looking South

Compound summary ─ Southern portal

The southern portal compound will be built in January 2013 and will be operational for 18 months.A noise structure will be built over the tunnel portal and closed off for night works.The compound will include:•Tunnel office•Crib rooms•Storage•Water treatment plant

Compound summary ─ old fish farm at Knockrow

A compound will be constructed at the old fish farm, Knockrow, in October 2012, pending RMS approval, to provide:•Site office•Crib rooms•Storage.

Construction/ operational water quality basin

Existing nursery shade cloth

Construction water quality basin

Construction water quality basin

Site compound

Compound summary ─ Ross Lane

A compound will be operational at Ross Lane from October 2012 for 24 months to provide:•Site office•Crib rooms•Storage•Plant deliveries.

Traffic management at Pacific Highway (Bangalow)

• The existing southbound lanes of the Pacific Highway at Bangalow will be closed to construct the new northbound carriageway of the upgrade.

• The works will require closure of the existing southbound carriageway, with traffic diverted to the northbound carriageway under a contra−flow traffic arrangement (one lane in either direction).

• The contra−flow will be implemented in three stages and will be in place for the duration of the project.

Traffic management at Pacific Highway (Bangalow)

Stage 1A ─ Northbound and southbound fast lanes closed for:• Median upgrade works to facilitate Stage 2 • Construction of crossovers• Approximately 13 weeks duration.

Stage 1B ─ Northbound slow lane and southbound fast lane closed for:

• Completion of median upgrade works• Construction of temporary noise mound adjacent to northbound Bangalow off ramp

• Approximately 12 weeks duration.Stage 2 ─ Contra-flow:

• Southbound carriageway closed to provide safe access for construction of the new northbound carriageway

• In place until project completion.

Traffic management at Pacific Highway (Bangalow) ─ Stage 1A

Stage 1A (13 weeks weather permitting)Northbound and southbound fast lanes closed for:•Median upgrade works to facilitate Stage 2 •Construction of crossovers•Median widening.

Construction works in median to accommodate traffic in future stage

Northbound and Southbound Pacific Highway traffic reduced to one lane and realigned onto the existing slow lanes

Traffic management at Pacific Highway (Bangalow) ─ Stage 1B

Stage 1B (12 weeks weather

permitting) Northbound slow

lane and southbound fast lane closed for:

• Completion of median upgrade works

• Construction of temporary noise mound adjacent to northbound Bangalow off ramp.

Construction works in median to accommodate traffic in future stage

Northbound Pacific Highway remains in one lane, realigned onto the existing fast lane, to allow construction access to build the noise bund at Bangalow Road exit

Southbound Pacific Highway on one lane, realigned onto existing slow lane, as per Stage 1A

Traffic management at Pacific Highway (Bangalow) ─ Stage 2

Stage 2 (Contraflow)

• Southbound carriageway closed to provide safe access for construction of the new northbound carriageway

• In place until project completion.

Northbound and southbound Pacific Highway traffic remains as single lanes, realigned onto the widened Northbound carriageway, to run in contraflow

Traffic management ─ Bangalow Road

•A section of Bangalow Road between the Pacific Highway southbound on−ramp and the Byron Creek bridge in Bangalow will be upgraded to ensure safe vehicle, pedestrian and construction interaction in the vicinity of the main site compound.•A 24 hour single lane contra−flow traffic arrangement will be set up and managed by mobile traffic lights under an approved traffic management plan. •The works will:• Provide alternative access arrangements for private properties and

access to the compound and construction site• Ongoing consultation with Byron Shire Council to discuss staging

works and timeframes.

Traffic management ─ Bangalow Road

Contra−flow under 24hr traffic lights

Eastbound lane closed for local road upgrade for approx. 4 weeksTraffic lights in place

24hrs/day to manage one way traffic flow

Westbound lane will be closed and upgraded once construction of eastbound is complete

Traffic lights in place 24hrs/day to manage one way traffic flow

Traffic management ─ Broken Head Road diversion

•A temporary diversion of Broken Head Road will be required during construction of the Broken Head Road overbridge. •The diversion is approximately 280 metres in length and will divert traffic to the north of the existing Broken Head Road (starting approximately 300 metres from the existing Pacific Highway intersection). •Works will take approximately five months, weather permitting. •Upon completion of the overbridge, traffic will be switched onto the new overbridge, which will form the permanent alignment of Broken Head Road.•Final tie-ins will be constructed at each end under traffic control, prior to the anticipated traffic switch onto the diversion.

Broken Head Road diversion ─ Stage 1

Stage 1•Eastbound lane closed•Construction of diversion route•24hr contra- flow under traffic lights.

Traffic lights in place 24hrs/day to manage one way traffic flow

Traffic lights in place 24hrs/day to manage one way traffic flow

Eastbound lane closed to allow construction of Stage 2 alignment

Broken Head Road diversion ─ Stage 2

Stage 2 The following will be completed under traffic control:•Construction of tie-ins•Final traffic switch.

Construction of crossover to be completed under traffic control

Construction of crossover to be completed under traffic control

Controlled environmental burning

What is controlled environmental burning?• Controlled environmental burning is a process whereby

noxious weeds and excess cleared vegetation is burned in a controlled, safe and environmentally friendly manner.

• The project team is proposing to use controlled environmental burning across the project – this is yet to be approved.

Controlled environmental burning

Why use controlled environmental burning?• It is a requirement that the project team use “weed free topsoil” on

the upgrade to avoid spreading noxious weed seeds.• It is a form of recycling unusable material from the site.• The ash from the controlled environmental burn will be recycled

back into the topsoil to improve quality.• The improved topsoil will be used along the alignment batters for the

revegetation process. • This operation keeps additional construction vehicles off the existing

Pacific Highway.• A cost effective and timely method to deal with excessive waste

materials along the alignment without further damaging the environment.

Controlled environmental burning

What is proposed?• The project team is proposing to

conduct a trial controlled environmental burn.

• The proposed location will have minimal impact on the surrounding environment, with little or no impact from the prevailing winds.

• It is also away from any residences, schools and water courses. Air is forced into the pit to fan the fire

Controlled environmental burning

•Once the trial has been completed, the controlled burn pit will be extinguished.•The ash at the bottom of the controlled burn pit will be sampled and sent away for testing to confirm approval to be mixed back into the topsoil stockpiles. •The pit will then be backfilled and compacted in layers, before being revegetated and covered with hay.•This will be reported back to EPA for approval on the project. Ash at bottom of controlled

burn pit will be tested

Tunnelling ─ overview

• History • Tunnelling methods• Selection of method for St Helena works • Tunnel environments• Excavation activities• Lining activities• Cut and cover sections• Tunnel fit-out and commissioning.

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History of tunnelling

• Oldest tunnel located in Turkey — estimated to be built between 2000 and 5000 years ago.

• First tunnels used primarily for water and for defence.

• Conditions have improved significantly since early days.

Road tunnels

Benefits•Reduced surface road congestion•Avoid built up areas•Avoid steep grades •Reduce travel times•Navigate watercourses•Reduce surface impact.•Maintain fauna passages across roadways

Portal to Cross City tunnel, Sydney

Methods of tunnel construction

Tunnel construction methods: •Cut and cover tunnels•Mechanical excavation•Drill and controlled blast excavation (St Helena tunnel)

Installation of rock bolts

St Helena tunnel

Selection of work methods was based on:

• Very hard rock• Large, elliptical cross-section• Short overall length• Drill and controlled blast most

appropriate and efficient method• Cut and cover sections at each

end.Geology of St Helena hill depicting hard rock

Cut and cover tunnels

• Simple method of construction• Earth is cut away and replaced

after construction• Suited to shallow tunnels• High temporary surface impact• Generally required at tunnel

portals.

Cut and cover tunnel construction

Drill and controlled blast tunnels

• Suited to medium to very hard rock• Used since 19 Century• Adaptable to different tunnel

geometries• Cyclical method of tunnelling• Efficient for short tunnels.

Jumbo drilling holes for explosives

Tunnel environments

• Ground support– Rock bolts– Shotcrete– steel ribs / lattice girders

• Ventilation– Types of ventilation– Dust– Gas monitoring

Roadheader with ventilation ductrunning alongside

Rock bolts

• Rock bolts are used to fix segments of rock that may be able to move after excavation• Used extensively in mining,

tunnelling and slope stability• St Helena tunnels will use over

3000 rock bolts.

Shotcrete

• Sprayed concrete or ‘shotcrete’ has been in use since early 1900s• Used extensively in construction• Provides protection from loose

rock falling from overhead, as well as additional structural support• Supports and strengthens

slopes.

Application of shotcrete

Excavation activities

• Drilling and loading• Controlled blasting and mucking• Ground support • Tunnel excavation is

cyclical in nature.

Excavation cycle

Drilling and loading

Drilling and loading methodology:• Holes are drilled and

then loaded with explosives• Uses mechanical drilling

equipment• A designed, controlled blast

pattern is readied for blasting.A jumbo has multiple drilling booms and can also be used for installing

roof bolts.

Tunnel controlled blasting ─ explosives

• Detonators are used to initiate the explosive reaction– Non-electronic– Electronic– Electric

• Carefully planned timing and controlled blast sequencing improves efficiency and reduces quantity of explosives required• Boosters are connected to

detonators to provide energy to initiate the bulk explosive.

Detonator assembly and boosters

Explosives

Ammonium nitrate emulsion• Stored as an oxidising agent,

not as an explosive• Significantly safer than

nitro-glycerine• Sensitised to be an explosive,

as required for controlled blasting• Must be initiated by a smaller

explosive (typically boosters)• Provides the majority of

the explosive energy.

Ammonium nitrate used in blasting

Controlled blasting and mucking

• Controlled blast detonated• Timing, spacing and quantity

key to efficient blasting• Once blasted, broken rock is

removed from the tunnel using mechanised equipment.

Rock and debris from blasts are loaded onto trucks underground for removal

Ground support

• Scaling is performed to remove loose rocks hanging from the excavation• Shotcrete is used to provide

a support arch to work under• Bolts are installed to hold

large segments of rock that may move over time.

Bolt installation

Waterproof lining

• Stops groundwater draining into the tunnel• Designed to prevent water

draining along the length of the tunnel• Uses high tech polymers

welded together• 40,000m2 will be used in the

St Helena tunnels.

Installing waterproof lining

Steel fixing

• Provides reinforcement to permanent concrete lining• Labour intensive work• St Helena tunnels will use over

2000 tonnes of steel• Steel work gantry will be used for

arch section for access and safety. Steel reinforcement before concrete

pour

Permanent concrete lining

• Large 12m and 23m long steel forms used– Arch form– Invert form

• Arch form weighs over 200 tonnes• Concrete placed in-situ• After concrete has set, forms

travel to the next segment.Concrete arch form assembly

Permanent concrete lining

• 500mm thick in mined section of tunnels• 800mm thick in cut and cover

section of tunnels• Over 30,000m3 of concrete

to be used in St Helena tunnels• Design life of 100 years.

Concrete lining in roof

Cross passages

• Smaller excavations connecting the northbound and southbound tubes of the tunnels• Cross passages will allow for safe

travel between tunnels, in case of emergency• Pedestrian and wheelchair

accessible.

Typical cross passage being constructed between tunnels

Tunnel construction ─ final stages

Tunnel landscaping, fit-out and commissioning• Backfill and landscaping• Tunnel fit-out works– Electrical services– Lighting– Signage– Pavement– Fire suppression system– Ventilation

• Tunnel control centre.

Artist’s impression of southern tunnel portal from a road user’s view

Landscaping

• Cut and cover section will have fill replaced back to blend into the natural surface at St Helena Hill• Area will be landscaped

to minimise visual impact of tunnel entrances.

Tunnel fit−out works

The tunnel fit−out incorporates the installation of services for the safe operation of the tunnel including:•Fire deluge systems•Ventilation•Variable speed signs and variable message signs. Artist’s impression of tunnel interior with

feature safety cross passages

Tunnel fit-out works cont’d

Fit−out works include the following installations:•6km of high voltage wiring•12km pipework for fire system•Over 3000 lights with emergency back-up power•20 CCTV cameras to monitor tunnel traffic and safety conditions•32 reversible jet fans •Safety marking of cross passages.

Tunnel control centre

Operation and diagnostics of tunnel control systems will:•Check status of pumps or electrical systems•Operate fans to control tunnel air quality•Use CCTV to monitor smoke or fire •Operate deluge system.

Artist’s impression of tunnel control centre

Community information, consultation and involvement

Consultation ongoing:• Meetings with property owners to support property adjustments

(continuing).• Meetings with residents for local road upgrades (continuing).Stay involved: 1800 882 787 (toll free inquiries and complaints line) communityinfo@t2e.com.au reply paid 85913 PO Box 604, Bangalow NSW 2479 www.rms.nsw.gov.au/pacific (prompts to Tintenbar to

Ewingsdale)Next community information session: Tuesday 18 Sept. 2012