PORT HEDLAND NELSON POINT DREDGING LAND USE MANAGEMENT PLAN

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					                AUGUST 2009




            PORT HEDLAND
   NELSON POINT DREDGING
LAND USE MANAGEMENT PLAN
LAND USE MANAGEMENT PLAN


                                                      Table of Contents
1            INTRODUCTION .......................................................................................................................1 
1.1          PROJECT OVERVIEW .............................................................................................................1 
1.2          PLAN OBJECTIVES .................................................................................................................1 
1.3          LEGAL REQUIREMENTS AND GUIDELINES .........................................................................2 

2            PROJECT DESCRIPTION........................................................................................................3 

3            POTENTIAL IMPACTS & MANAGEMENT..............................................................................5 
3.1          PROPOSED GUIDING MANAGEMENT PRINCIPLES ............................................................5 
3.2          MANAGEMENT MEASURES ...................................................................................................5 

4            MONITORING ...........................................................................................................................7 

5            PERFORMANCE INDICATORS ..............................................................................................8 

6            RISK ASSESSMENT ................................................................................................................9 




                                                                 Figures
Figure 1 – Proposed Offshore Spoil Ground One and Onshore DMMA H ..............................................4 

                                                                  Tables
Table 1 – Key Project Characteristics ......................................................................................................1 
Table 2 – Summary of Potential Impacts Resulting from Land Use Associated with DMMA H...............9 




AUGUST 2009                                                                                                                                Page i
LAND USE MANAGEMENT PLAN

1     INTRODUCTION

1.1    PROJECT OVERVIEW
BHP Billiton Iron Ore is seeking parallel approval under the State Environmental Protection Act 1986
(EP Act) and the Commonwealth Environment Protection and Biodiversity Conservation Act 1999
(EPBC Act) to undertake a dredging program within the Port Hedland Inner Harbour, adjacent to
existing facilities at Nelson Point.
The proposal involves the dredging of approximately 6.0 Mm3 of material for two new berth pockets,
extensions to the existing departure channel and swing basin at Nelson Point, to accommodate
vessels of approximately 250,000 DWT.
Dredged material is proposed to be managed at two dredge material management areas (DMMA)
depending on a number of factors including its potential to generate acid sulphate soils, available
dredge types and access (depth) requirements for dredge equipment.
Up to 2.7 Mm3 of material including potential acid sulphate soil (PASS) material will be dredged using
a Backacter Dredge and disposed of offshore to Spoil Ground One using hopper barges. Up to
4.0 Mm3 of dredged material will be dredged using a Cutter Suction Dredge and pumped onshore to
DMMA H.
The key characteristics of this proposal are outlined below in Table 1.

                                 Table 1 – Key Project Characteristics
           Element                                               Description
Duration of dredging             Offshore disposal: Approximately 68 weeks (based on 2.7 Mm3)
                                 Onshore disposal: Approximately 46 weeks (based on 4.0 Mm3)
Area of marine disturbance for   Not more than 60 ha at Nelson Point (south)
dredging
Volume of material to be         Approximately 6.0 Mm3 (including allowance for over-dredging)
dredged
                                                     3
Offshore disposal of dredged     Not more than 2.7 Mm to Spoil Ground One
material
                                                     3
Onshore disposal of dredged      Not more than 4.0 Mm to DMMA H (excluding bulking*)
material
Area of land disturbance for     Construction footprint: Not more than 204 ha
DMMA H                           Perimeter bund height: Not more than +9.0 m AHD (Australian Height Datum)
Area of mangrove clearance       Closed Canopy Mangroves: Not more than 0.22 ha
                                 Scattered Mangroves: Not more than 3.78 ha



1.2    PLAN OBJECTIVES
This Land Use Management Plan (LMP) has been developed to define the overall environmental
management objectives of DMMA H.
The LMP proposes guiding principles and performance indicators that will assist in the management of
DMMA H, following completion of the dredging and associated activities.
The objectives of the LMP are to:
•      manage the DMMA H land surface to ensure that it is safe, stable and suitable for the
       designated end land use;
•      minimise adverse effects on the environmental values of surrounding areas; e.g. dust
       generation, changes in surface water drainage, weed infestation and impacts on fauna;
•      maintain a landscaped view of the area; and
•      identify an environmentally sustainable final land use for DMMA H.



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LAND USE MANAGEMENT PLAN
1.3   LEGAL REQUIREMENTS AND GUIDELINES
The environmental objective for the land use is to ensure the rehabilitation of DMMA H achieves an
acceptable standard compatible with the intended land use.
The key EPA Position Statements and Guidelines that are likely to be of relevance to land use
management are as follows:
•     EPA Position Statement 6: Towards Sustainability (2004);
•     EPA Position Statement 7: Principles of Environmental Protection (2004); and
•     EPA Guidance Statement No. 55: Implementing Best Practice in Proposals Submitted to the
      Environmental Impact Assessment Process (2003).




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LAND USE MANAGEMENT PLAN

2   PROJECT DESCRIPTION
The proposed dredging at Nelson Point is to allow for the construction of two new shipping berths
along with extensions to the existing berth pockets, departure channel and swing basin. When
completed, the berths will be able to accommodate vessels of approximately 250,000 DWT with a
breadth of 55 m and a length of approximately 350 m.
The program is comprised of the following:
•     dredging of two new berth pockets to a design depth of -19.2 m CD (chart datum);
•     extending and deepening the existing departure channel adjacent to the berths to a design
      depth of -14.8 m CD to allow for safe departure of loaded vessels;
•     extending and deepening the swing basin at Nelson Point to a design depth of -9.3 m CD to
      enable arriving vessels to gain access to the new berths; and
•     associated over-dredging of approximately 0.7 m due to dredging tolerances.


In order to effectively manage the dredged material, one offshore and one onshore site have been
identified as DMMA. The offshore Spoil Ground One is located in commonwealth waters north of the
Port Hedland Inner Harbour and immediately adjacent to existing Spoil Ground ‘I’. The onshore
DMMA H is located to the south of Lumsden Point, within the Port Hedland Harbour. The proposed
dredging footprint and associated DMMA are shown in Figure 1.
The dredging works will involve:
•     the dredging of PASS and non-PASS material with a Backacter Dredge with subsequent
      offshore disposal to Spoil Ground One via split hopper barges; and
•     the dredging of non-PASS material with a Cutter Suction Dredge and the pumping of dredged
      material onshore to DMMA H.


Capital works for the development of DMMA H will involve the following:
•     construction of perimeter earth bunds to +9.0 m AHD at DMMA H;
•     construction of an approximately 60 m wide pipeline corridor (reduced to 20 m in areas of closed
      canopy mangroves) from DMMA H north across Lumsden Point out to the harbour to allow the
      installation of two 900 mm internal diameter steel pipelines (one live, one as spare). This will
      allow for the pumping of material from the dredge to DMMA H. This corridor width is based on:
      ο     safe access for construction vehicle traffic;
      ο     windrows, batters and scour protection;
      ο     a temporary haul road on one side for construction of the pipeline corridor;
      ο     an allowance for turning areas and contractor laydown.
•     construction of an approximately 40 m wide overflow channel from DMMA H to South East
      Creek, including scour protection.


A construction boundary will be established around the bund walls and pipeline corridors including a
20 m buffer on each side of the overflow channel. This construction boundary will only be disturbed
during the project for construction activities such as lay down areas, haul roads and construction
access. Disturbance within this construction boundary will be minimised where possible.




AUGUST 2009                                                                                    Page 3
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                                                                                                                                                                        °
          Legend
              Dredged Material                               Dredge Buffer Zone                         Railway
              Management Area H
                                                             Spoil Ground One                           FMG Railway                                         0             1         2
              DMMA H Construction Footprint                                                                                                                                                                 Source:
                                                             Shipping Channel                           State/Commonwealth                                          kilometres                              Orthorectified Aerial Photograph: 06/2008 (BHPBIO)
              Nelson Point Dredge Footprint                                                             Jurisdiction Boundary                                                                               Topography: Geoscience Australia, GEODATA
                                                                                                                                                                                                            Topo 250K V3. State Boundary: AMBIS (2006)
                                                             Principal Road                                                                                 Scale @ A4: 1:100,000                           Channel: Navy Hydrographer (Aus00740)
                                                                                                                                                                                                            SP 1: 1210-C-00287.dgn 19/08/2008 (MPD JV)
                                                                                                                                                               Datum: GDA94                                 H: F112-C-00155_G 07/04/2009 (FAST)
                                                                                                                                                          Map Grid: MGA94 Zone 50                           Nelson Point: 112-SK-00501 A 30/03/2009 (FAST)
          Figure 1 Proposed Offshore Spoil Ground One and Onshore DMMA H                                                                                                                                                                650\g164_WV03712_Rev0
LAND USE MANAGEMENT PLAN
3     POTENTIAL IMPACTS & MANAGEMENT
Potential impacts associated with DMMA H in the period between the transfer of material and being
re-used or stabilised include:
•      potential increases in dust generation from DMMA H following completion of dredging;
•      introduction and establishment of weed species; and
•      modification of the landform resulting in altered local drainage which could lead to erosion and
       adjacent vegetation damage.



3.1    PROPOSED GUIDING MANAGEMENT PRINCIPLES
A degree of flexibility with respect to the management of DMMA H following the completion of the
dredging activities is required so that the actual final land use can be optimised as necessary. To
achieve this flexibility, the following guiding post-dredging management principles for DMMA H are
proposed:

Short-term (up to five years post dredging)
•      there will be no significant, physical off-site impacts;
•      there will be no unsafe areas where members of the general public could inadvertently gain
       access;
•      the short-term post dredging landform will be stable and respond to erosive forces;
•      implementation of weed management measures; and
•      the final land use for DMMA H will be determined in consultation with relevant stakeholders, and
       agreed with the Port Hedland Port Authority within five years of completion of the dredging.

Long-term (greater than five years post dredging)
•      there will be no significant, physical off-site impacts;
•      there will be no unsafe areas where members of the general public could inadvertently gain
       access; and
•      BHP Billiton Iron Ore will rehabilitate areas of DMMA H where dredged material has not been
       re-used. Rehabilitation activities will be finalised in consultation with relevant stakeholders.



3.2    MANAGEMENT MEASURES
BHP Billiton Iron Ore is committed to the sustainable use of the dredged material and will continue to
investigate options for re-use within the Port Hedland area. Furthermore, the nature of the fill
influences how it is managed and the ultimate landuse. Given these uncertainties, BHP Billiton Iron
Ore proposes to either:
•      re-use the dredged material within five years of the completion of dredging; or
•      implement long-term management measures outlined in the Land Use Management Plan, which
       will finalised in consultation with relevant stakeholders within five years of project completion.


It is likely that some of the dredged material to be stored in DMMA H will be suitable for re-use. During
the period between reclamation and potential re-use, this material will be managed in accordance with
the guiding principles discussed above, to ensure that it does not result in a significant dust emission
source and is not eroded during periods of heavy rains.

Vegetation
The dredged material is likely to be unsuitable in its existing state for vegetating due to high salt levels.
Surface water will be collected and retained in settlement ponds within DMMA H. If sufficient fresh


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LAND USE MANAGEMENT PLAN
water is available, areas to be revegetated will be irrigated to complement the natural salt flushing
processes. Subsequent to flushing, a layer of growth medium will be placed over the nominated areas
of the visual berms and revegetated with an appropriate selection of coastal vegetation.
BHP Billiton Iron Ore will investigate possible re-use of the dredged material. In the event that the
material is not utilised within a five year timeframe (following completion of dredging) the area will be
rehabilitated in accordance with the long-term guiding principles detailed above.

Dust and Wind Erosion
A crust is likely to form on DMMA H due to the saline nature of the source environment. Potential dust
lift off from the reclaimed areas will be managed through establishment of crust to seal the exposed
surfaces and dust suppression techniques will be utilised as required. The surface of the dredge
management areas will be stabilised upon completion of dredge spoil disposal activities.

Introduction and establishment of weed species
Ongoing weed management activities following construction will include:
•     conducting regular monitoring/inspections for the presence of weeds within areas of
      disturbance; and
•     treatment of infested areas, including the application of herbicides to pre-emergents where
      appropriate.

Modification of the landform resulting in altered local erosion, stability and drainage
Erosion within DMMA H will be managed through the installation of appropriate drainage controls.
If required, stormwater channels will be constructed to divert stormwater around the construction site.
Stormwater flow and possible storm surge events will be calculated and allowed for when designing
these channels. The external batters of DMMA H will be intercepted by tidal flows intermittently and
will periodically also receive large storm surge flows. Erosion control measures will be considered on
exposed wall surfaces to manage potential erosion impacts from intermittent tidal influence.
Structural integrity of DMMA H will be maintained during cyclonic rainfall events by maintaining a
combination of suitable internal wall height free-board above the stored dredge material, combined
with a suitably sized stormwater emergency overflow structure and suitable engineering design of the
tidal intercept zone.




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LAND USE MANAGEMENT PLAN

4   MONITORING
Following cessation of dredging and reclamation activities, BHP Billiton Iron Ore will develop and
implement a monitoring program to evaluate the management of DMMA H and assess guiding
management principles. Monitoring will also be undertaken to assess against the performance
indicators outlined below. It is expected that the following will be monitored:
•     visual inspection of wind-born dust during high wind periods;
•     surface water quality and flows within the modified drainage areas;
•     public safety;
•     rehabilitation performance, including weeds; and
•     stability of landforms.




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LAND USE MANAGEMENT PLAN
5   PERFORMANCE INDICATORS
The following performance indicators are proposed:
•     minimal additional wind-born dust generated from DMMA H during periods of high winds;
•     no uncontrolled erosion impacts beyond DMMA H drainage system;
•     sediment loads in drainage system stormwater flows cause minimal change to receiving water
      quality;
•     reflective warning signs stating “Warning – Unstable Material – NO ENTRY” erected at 100 m
      intervals around the perimeter of DMMA H prior to the storage of dredge material;
•     adequate vegetation established over 80% of revegetated areas within two years of
      revegetation;
•     no more than 10% of DMMA H surface area infected by weeds; and
•     no uncontrolled slumping of berm surfaces beyond geotechnical limits.




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LAND USE MANAGEMENT PLAN

6    RISK ASSESSMENT
A summary of the key potential impacts for land use and their associated management measures as
well as their associated severity, likelihood and residual risk is provided in Table 2.
Potential impacts are considered to be ‘known to happen, but only rarely as defined in the BHP Billiton
Risk Guidelines. Any impacts are considered to be ‘moderate short term effects not effecting
ecosystem function’ except for the establishment weed species which is considered to have a severity
of ‘limited damage to minimal area of low significance’ as defined in the BHP Billiton guidelines. The
residual risk (i.e. after the management measures proposed in the plan have been applied) has
therefore been determined to be minor.

    Table 2 – Summary of Potential Impacts Resulting from Land Use Associated with DMMA H

                                                                                                  Residual Risk
Impacts                                   Management Measures
                                                                                              S      L      RRR

Dust generation from DMMA H               Refer to dust management measures outlined          3     0.3     Minor
                                          in Section 9 of the ERD. Measures include:                        (0.9)
                                          •    Dust suppression management program
                                               during construction.
                                          •    Dust suppression management program
                                               for DMMA H reclaimed area.
                                          •    Complaints management procedure in
                                               place.
                                          •    Ongoing stakeholder engagement and
                                               communications for dust management.
                                          •    Published dust reporting.
                                          •    Continue engagement with Community
                                               Reference Croup and Industry Council
                                               Group.
                                          •    Continue consultation and engagement
                                               with heritage and native title stakeholders.
                                          •    Real time dust monitoring at Port Hedland.
Introduction and establishment of         Proactive hygiene measures and treatment of         1     0.3     Minor
weed species                              infested areas, as required.                                      (0.3)
                                          Implementation of construction Environmental
                                          Management Plan
Modification of the landform resulting    Installation of appropriate drainage controls.      3     0.3     Minor
in altered local erosion, stability and   Designed to accommodate interception with                         (0.9)
drainage                                  tidal movement.




AUGUST 2009                                                                                                 Page 9