Regulator Expectations for Site Relinquishment

1. Regulator Expectations for Site Relinquishment Eugene Bouwhuis (Senior Environmental Inspector) 20 May 2009

2. Mining Regulations 1981 Each site varies dependent upon issues/ social/ community/ environmental/ safety Mining Regulations 1981 Each site varies dependent upon issues/ social/ community/ environmental/ safety

3. Mining Act 1978 requirements All mining tenements granted in Western Australia have a number of environmental requirements under the Mining Act 1978 and Regulations 1981 The Minister may impose conditions at any time including environmental bondsThe Minister may impose conditions at any time including environmental bonds

4. Mining Act 1978 requirements Environmental Conditions Mining Proposals (Section 70O) Environmental Bonds Regulation / Enforcement Community Consultation (MP guidelines) Mine Closure / Rehabilitation (� � �) Mining Act Amendment Act 2004 proclaimed 10 Feb 2006 Mining Proposal are prescribed document 70O UPB guaranteed by a bank or approved financial institution 120H Direction To Modify 120M Stop Work Order Inspectors appointed under section 11 Section 4.6 of MP Guideline Consultation land owners Land vestees Section 4.7 requires preliminary mine closure planMining Act Amendment Act 2004 proclaimed 10 Feb 2006 Mining Proposal are prescribed document 70O UPB guaranteed by a bank or approved financial institution 120H Direction To Modify 120M Stop Work Order Inspectors appointed under section 11 Section 4.6 of MP Guideline Consultation land owners Land vestees Section 4.7 requires preliminary mine closure plan

5. DMP basic closure criteria Safe Stable Non-polluting Self sustaining native ecosystem/or agreed alternative end land-use Safe for humans and animals. Native fauna / stock. Stable landforms essential. No dusting, no leachates (salt and AMD), no elevated metals or elements above background. Land owner or vestee must accept in writing liability and responsibility for the site post mining.Safe for humans and animals. Native fauna / stock. Stable landforms essential. No dusting, no leachates (salt and AMD), no elevated metals or elements above background. Land owner or vestee must accept in writing liability and responsibility for the site post mining.

6. Relinquishment process Rehabilitate & monitor site Allow time Provide documentation to support request for relinquishment DMP Senior EO conducts inspection & makes recommendations to Director Bonds retired, conditions deleted Tenements surrendered Collection of baseline and supportive relevant data. May take many years hence progressive rehabilitation important. Need to be exposed to representative climatic conditions. Eg drought. Monitoring results summary and interpretation by appropriate expertise.Collection of baseline and supportive relevant data. May take many years hence progressive rehabilitation important. Need to be exposed to representative climatic conditions. Eg drought. Monitoring results summary and interpretation by appropriate expertise.

7. Most common errors Poor knowledge of materials Inadequate stakeholder consultation Variance from commitments Poor environmental management/ supervision Fail to seek appropriate technical input Inadequate financial provisioning No/inadequate rehab. trials Inadequate monitoring Dispersive / hostile waste materials. Various stakeholders govt/community/private land. Consult with all stakeholders early. Meet other approval requirements eg. Ministerial conditions EP Act 1986. The approved documents and contents are legally binding. Landforms to cope with 1 in 100 year, 72h storm event. Poor supervision can result in very costly reworks. Difficult issues may require input from various technical experts. Closure and relinquishment is very expensive. Appropriate resourcing is required. No historic data presented, no trends over time.Dispersive / hostile waste materials. Various stakeholders govt/community/private land. Consult with all stakeholders early. Meet other approval requirements eg. Ministerial conditions EP Act 1986. The approved documents and contents are legally binding. Landforms to cope with 1 in 100 year, 72h storm event. Poor supervision can result in very costly reworks. Difficult issues may require input from various technical experts. Closure and relinquishment is very expensive. Appropriate resourcing is required. No historic data presented, no trends over time.

8. DMP expectations 1) Pits Abandonment bund (zone of instability) Backfilled (allow for settlement) Acceptable pit water quality (eg.not at significant variance to background levels) Other potential uses (pit lake, reformed into the surrounding topography Surface infrastructure � public roads, rail, town sites, private land, neighbouring tenements, reserve land. Aquiculture, recreational, water source, in-pit TSF.Surface infrastructure � public roads, rail, town sites, private land, neighbouring tenements, reserve land. Aquiculture, recreational, water source, in-pit TSF.

9. DMP expectations 2) Tailings Storage Facilities (TSFs) Stability analysis/ geotechnical evaluation Capped appropriately Ground water quality acceptable Vegetation (rehab. & surrounding) Surface water management (1:100 rainfall/ 72 hour) Guidelines for safe design and operating standards for TSFs. Categories 1 to 3 Hazard ratings Concave, convex for final surfaces.Guidelines for safe design and operating standards for TSFs. Categories 1 to 3 Hazard ratings Concave, convex for final surfaces.

10. DMP expectations 3) Waste dumps Long term safe, stable, non-polluting landform Final design well trialled Hostile material well encapsulated Good surface drainage control Functioning native ecosystem Monitoring results. Dispersive materials, materials prone to piping. Monitoring results against an analogue.Monitoring results. Dispersive materials, materials prone to piping. Monitoring results against an analogue.

11. DMP expectations 4) Plant, workshops, offices & camps Totally deconstructed Hazardous substances removed Contaminated areas treated Concrete foundations removed/buried Drainage control implemented All rubbish removed (foreign debris) Revegetated Buildings, poer cables, pipelines (gas, water, tailings, chemical). Hydrocarbons, process liquors, chemicals, bioremediation. Surface drainage re-instated. Buildings, poer cables, pipelines (gas, water, tailings, chemical). Hydrocarbons, process liquors, chemicals, bioremediation. Surface drainage re-instated.

12. DMP expectations 5) Infrastructure (eg. haul rds, airstrips, pipelines, powerlines, borefields, borrow pits) Ripped up & structures removed Bores sealed (or accepted by 3rd party) Dams � liners removed, backfilled Spill areas remediated Spread with topsoil & revegetated Legally able to eg. Pastoralists retaining bore or road or airstrip. Must be ratified by Pastoral Lands Board as a legitimate pastoral improvement.Legally able to eg. Pastoralists retaining bore or road or airstrip. Must be ratified by Pastoral Lands Board as a legitimate pastoral improvement.

13. Poor examples Poor design (batters too long) Topsoil excessive Lack of armouring Poor surface water management Water Induced Erosion due to poor material selection and construction.Water Induced Erosion due to poor material selection and construction.

14. Poor examples Poor placement of waste dump Poor knowledge of site drainage Interference with drainage resulting in ponding of surface water against mine infrastructure and AMD.Interference with drainage resulting in ponding of surface water against mine infrastructure and AMD.

15. Poor examples Poor environmental management (salts leaching from mine waste landform)

16. Poor examples Acid mine drainage No topsoil recovery

17. Good examples Progressive rehabilitation Fresh topsoil & not excessively thick Good design

18. Good examples Contoured to integrate with surrounding landforms Fauna habitat provided

19. Good examples Private land post mining with improvements Re-contoured land, water source, pasture improvements, fencing, solar pumps, buildings, roads.Re-contoured land, water source, pasture improvements, fencing, solar pumps, buildings, roads.

20. Have realistic expectations Don�t expect bond reductions the day after machinery leaves the waste dump Don�t seek relinquishment with no/ inadequate monitoring data Consider position of regulator (responsible for interests of the WA community)

21. Take home messages Positive steps towards relinquishment: Engage stakeholders, establish end land-use Know your waste materials Strip topsoil progressively Develop/Fine tune completion criteria Progressively rehabilitate Trial (test, monitor, evaluate)

22. Thankyou - any questions? Eugene Bouwhuis Mineral House 100 Plain Street, East Perth eugene.bouwhuis@dmp.wa.gov.au Ph. (08) 9222 3097 The end