KML DMP Geotechnical Considerations open pit

1.1 Senior mine management has demonstrated a clear understanding and commitment to address the geotechnical issues in open pit mining using sound geotechnical engineering practice<br><br>Method: Sight minutes of design and planning meetings. Check that the process is current. Refer to MSIR r. 13.8(1).

1.2 The geometry and design life of each open pit excavation and associated waste dumps has been determined and formally documented<br><br>Method: Sight guidelines. Refer to MSIR rr. 13.8(1), 13.12 and 13.13.

1.3 The mine has utilized geotechnical input in the mine design process<br><br>Method: View documentation with geotechnical data from geotechnical boreholes, use knowledge from nearby pits and waste dumps if the geology can be demonstrated to be adequately similar. Geotechnical data should include planes of weakness, groundwater and surface water rock stress field and rock mass strength from core or undisturbed sample testing. Drilling programs have been used to identify potential areas of contact of the mine with large aquifers/water bearing bodies and have quantified the expected water quality and make over time. Site relevant design documentation. Refer to MSIR r. 13.8(1).<br>

1.4 The positioning of open pit walls and waste dumps have taken into consideration the tenement boundaries, the locations of major surface facilities and the geotechnical parameters that can affect the integrity of these facilities<br><br>Method: Sight Project Management Plan (PMP), any PMP updates/addenda and check current design documentation. Refer to MSIR rr. 13.8(1) and 13.15.

1.5 A multi-disciplinary, mine design and planning process exists and is formally implemented<br><br>Method: Sight minutes of design and planning meetings. Check that the process is current. Refer to MSIR r. 13.8(1).

1.6 A set of development planning and design criteria have been drawn up to provide general guidance in mine planning and design for open pits, waste dumps, ROM pads and major haul routes. e.g. stockpiles and waste dumps have been designed to take into account the full range of foundation materials, stockpile/dump materials and ground/surface water conditions<br><br>Method: Sight guidelines. Refer to MSIR rr. 13.8(1), 13.12 and 13.13.<br>

1.7 Geotechnical domains are used to divide the rock mass into volumes of similar expected ground behavior in three dimensions <br><br>Method: Sight documentation that presents the inherent variability of the geological structure, rock stress levels, rock mass strength and deformation characteristics. Refer to MSIR r. 13.8(2).

1.8 The mine has developed a ground control management plan (GCMP) relevant to the local ground conditions and mining strategies<br><br>Method: Review the ground control management plan. Verify if the plan complies reasonably well with the department guidelines. Refer to MSIR r. 13.8(1).<br>

1.9 The mine has both short and long term production schedules that take into account the likely geotechnical impacts which may have an adverse affect on safety<br><br>Method: Sight long term and short term planning/scheduling documents, check for variation in blasting near temporary walls, workplace inspection, dewatering design and effects, ramp design, reinforcement scheduling, progression of mining working benches and formation of final walls etc.

1.10 An assessment has taken place to determine whether all boreholes need to be fully grouted to prevent contact with water bearing bodies and those requiring grouting are sealed<br><br>Method: Sight plans showing location of boreholes and the current status of these holes. Also requires supportive documentation to verify the decisions made with respect to these boreholes. Refer to MSIR r. 13.8(2)(c).

1.11 The boundaries of water filled hazards have been accurately determined and a safe working distance specified according to the ground conditions and the mine plan<br><br>Method: Sight design criteria. Refer to MSIR rr. 13.8(2)(c) and 13.8(3).

1.12 The interaction of near-by underground mine voids has been taken into consideration for the mine design and excavation sequencing to minimize the potential for adverse stability conditions on pit walls<br><br>Method: Sight design criteria/documentation. Refer to MSIR r. 13.8(3).

1.13 Water diversion and storage structures are designed according to acceptable engineering standards<br><br>Method: Sight engineering designs and as constructed diagrams and supportive documentation. Refer to MSIR r. 13.8(2)(c).

1.14 Internal water drainage strategies exist for open pits, waste dumps and haul roads<br><br>Method: Check pit designs and inspect open pit. Refer to MSIR r. 13.8(2)(c).

1.15 A justifiable design criteria exists for mining in close proximity to surface water drainage paths and open pit sumps where underground workings exist<br><br>Method: Sight design criteria. Refer to MSIR r. 13.8(2)(c).<br>

1.16 The mine has a formalized plan for closure of the open pit<br><br>Method: View the site abandonment plan. Refer to MSIR r. 13.8(1).

1.17 The closure plan considers issues such as drainage, visibility (dusting & road bends), abandonment bunding and erosion materials spreading onto sensitive land<br><br>Method: Sight closure plan details. Determine if the plan specifies a process for closure that covers a strategy for achieving a final practicable and safe result and ensures:<br>1. All slopes are reassessed in accordance with the slope management system<br>2. The required, actions are undertaken to ensure that slopes are maintained in a safe condition<br>3. Barriers and signs prevent inadvertent access to areas affected by slopes<br>4. All reports, plans, logs and records are indexed and preserved for future reference.<br>Refer to MSIR rr. 3.16 and 13.15.

1.18 The design of final pit walls takes into account time-dependent effects on rock strength, the degree of inherent uncertainty, and reflects the associated need for conservative slope design criteria<br><br>Method: Sight design criteria and methodology used to derive the long-term geotechnical model. Refer to MSIR r. 13.8(1).

1.19 The closure plan has been approved by the relevant regulatory bodies and nearby land owners<br><br>Method: Sight documents of acceptance by relevant stakeholders. Refer to MSIR rr. 3.15 and 13.16.<br>

2.1 The mine has implemented the ground control management plan (GCMP) for pit walls, stockpiles and waste dumps<br><br>Method: Check current geotechnical design and input. Refer to MSIR rr. 13.8(1), 13.8(2) and 13.12.

2.2 The GCMP has a review period and is signed off by relevant management bodies each time a modification is made to that document<br><br>Method: Check current and earlier versions of the GCMP. Refer to MSIR r. 13.8(1).

2.3 All relevant personnel understand their roles within this site GCMP<br><br>Method: Interview relevant personnel in the mine. Refer to MSIR r. 13.8 (1)

2.4 The mine has a suitably qualified person(s) to oversee geotechnical issues or has appropriate visitation by contracted geotechnical experts with backup from appropriate site personnel<br><br>Method: Determine if there is a full time or part time competent person appointed for geomechanics duties. Is this sufficient considering the geomechanics issues at the mine? What are the qualifications of the competent person? Refer to MSIR r. 13.8 (1).

2.5 The site has formalised procedures for geotechnical mapping commensurate with the rate of mining and the specific site safety risks for those undertaking mapping<br><br>Method: Sight evidence, databases, plans sections, displaying geotechnical data. Sight geotechnical domains definition, are these current. Refer to MSIR r. 13.8 (1).

2.6 Geotechnical mapping is being carried out on a regular basis consistent with the rate of mining and areas requiring additional geotechnical information<br><br>Method: Sight the process or work procedure describing which locations are to be mapped geotechnically. Check to make sure relevant, accurate information is being gathered from the mapping process. Refer to MSIR rr. 13.8 (2)(a) and 13.8(2)(b).<br>

2.7 The as-mined pit wall/dump conditions and geotechnical model are used to make risk assessments for each mining area<br><br>Method: Sight the process or work procedure describing which locations are to be mapped geotechnically. Check to make sure relevant, accurate information is being gathered from the mapping process. Refer to MSIR rr. 13.8 (2)(a) and 13.8(2)(b).<br>

2.8 Safety/catch berms are maintained such that sufficient catch volume remains to halt the movement of rock down the slope<br><br>Method: Observe in pits whether berms have rill piles that do not extend to the berm crest and that suitable access remains in all areas, taking into consideration the site method used for scaling. Refer to MSIR r. 13.9(2).<br>

2.9 For situations where berms are not in a suitable condition, formalised procedures are in place and implemented to prevent rock from toppling down onto the working areas<br><br>Method: Sight formal procedures and inspect mine areas e.g. windrows to restrict access to the toe of the slope. Refer to MSIR r. 13.9(2).

2.10 The mine has a system for house-keeping loose material after each wall blast and if blocks of loose rock come to rest at the crest of berms<br><br>Method: Observe procedures, inspect mine. Refer to MSIR r. 13.9(2).

2.11 Where underground workings or natural voids exist, the mine has developed formal safe working practices for mining through voids that are formally approved and implemented<br><br>Method: Observe SWP and design criteria, inspect mine plan database. Refer to MSIR r. 13.8(3).

2.12 The mining through voids document complies with the departmental guidelines on open pit mining through underground workings as a minimum standard<br><br>Method: Observe SWP and design criteria, inspect mine plan database. Refer to MSIR r. 13.8(3).

2.13 Appropriate bunding strategies have been developed and implemented to limit access to "drop-offs" from levels above (general traffic ramps and dump tip heads)<br><br>Method: View design and construction documentation. Refer to MSIR rr. 13.5(2), 13.7(5), 13.8(1).

2.14 Waste dump procedures have been developed to take into account the full range of excavation materials being dumped and ground/surface water conditions in all areas<br><br>Method: View dump design protocol. Refer to MSIR r. 13.5(1).

2.15 Waste dump management includes policies for drainage at the top and bottom of dumps, tip head design and management, foundation stability, and dust, where it is an issue<br><br>Method: Sight operational design criteria. Refer to MSIR r. 13.5(1).<br>

2.16 Where areas of significant hazard are identified (e.g. undertaking cutbacks, areas with high rates of deformation), suitable safe working practices are developed and implemented to protect personnel that may work below the level of the cut-back<br><br>Method: View generic protocol or specific strategy if such a situation exists at the mine. Refer to MSIR r. 13.9.

2.17 Emergency action plans or protocols exist in the event of a potential high risk ground movement event<br><br>Method: View generic protocol or specific strategy if such a situation exists at the mine. Refer to MSIR r. 13.8(1).

2.18 The mine conducts regular, on-going, checks of pit walls to determine the need for scaling over time for various types of work (e.g. installation of reinforcement or monitoring installation) and documents any rehabilitation work carried out<br><br>Method: Interview relevant persons and inspect working areas. Refer to MSIR r. 13.9(9).

2.19 Records are kept of scaling work undertaken<br><br>Method: Inspect scaling records. Refer to MSIR r. 13.9(9).

2.20 The mine has a standard specification for scaling equipment and these specifications can satisfy the full extent of operating conditions<br><br>Method: Check for scaling equipment specifications. Refer to MSIR r. 13.9(9).

2.21 The mine enforces a standard work procedure for scaling<br><br>Method: View scaling SWP. Refer to MSIR r. 13.9(9).

3.1 A standard drilling and blasting pattern exists, and is always used, for each geotechnical domain, and influence of groundwater<br><br>Method: Sight the documented standard for each geotechnical domain. Refer to MSIR rr. 13.8(1) and 13.8(2)(f).

3.2 SWP’s are available for drilling and blasting operations<br><br>Method: Interview personnel. Sight the SWP for production and near wall blasting. Sight a near-slope charging plan to verify that the blast design procedures are routinely followed. Refer to MSIR rr. 13.8(1) and 13.8(2)(f).

3.3 Suitable subgrade drilling and blasting is undertaken to allow for safe trafficking conditions without damaging batter crests<br><br>Method: Check subgrade drilling procedures and inspect open pit conditions. Refer to MSIR rr. 13.8(1) and 13.8(2)(f).

3.4 All final wall drilling equipment is fitted with automatic hole parallelism and angle controls that are maintained in good working order<br><br>Method: Interview drill operators. Refer to MSIR rr. 13.8(1) and 13.8(2)(f).

3.5 Over break/under break at the excavation perimeters is monitored<br><br>Method: Sight blast performance records and evaluation documents. Refer to MSIR rr. 13.8(1) and 13.8 (2)(f).

3.6 A system exists to correct mining techniques where excess over break or burden at the toe is encountered<br><br>Method: Sight relevant documentation. Refer to MSIR rr. 13.8(1) and 13.8(2)(f).

3.7 Where applicable, the impact of blasting on nearby structures e.g. tailings storage facilities or water diversion structures has been adequately assessed and taken into consideration when designing all forms of blast<br><br>Method: Check relevant documentation where such structures exist (e.g. paddock dam, tailing storage facilities (TSF), inside a working open pit). Refer to MSIR rr. 13.8(1) and 13.8(2)(f).<br>

4.1 The mine has determined ground support strategies for each type of support/reinforcement, geotechnical domain and dimension of excavation<br><br>Method: Check formal documentation, may form part of the GCMP. Refer to MSIR r. 13.8(2)(d).

4.2 A recognised rock support and reinforcement design method has been used to design the required rock support and reinforcement system<br><br>Method: Sight design criteria and calculations. Refer to MSIR r. 13.8(2)(d).

4.3 A technical specification exists for all the rock support and reinforcement systems in use<br><br>Method: Sight specification documentation. Refer to MSIR r. 13.8(2)(d).

4.4 The mining cycle has been adapted to the ground conditions to suit any delays in installing the ground support<br><br>Method: View review documentation that confirms the suitability of proposed installation strategies with respect to mine scheduling Refer to MSIR r. 13.8(2)(d).

4.5 Written standard work procedures have been developed for the installation of the various types of rock support and reinforcement in use at the mine<br><br>Method: Interview personnel. Observe installation. Sight copy of SWP. Compare SWP with observed procedure. Refer to MSIR r. 13.8(2)(d).

4.6 The installation procedures provided by the supplier(s) of the rock support and reinforcement elements are being followed<br><br>Method: Sight supplier installation standards, installation records. Refer to MSIR r. 13.8(2)(d).

4.7 The storage and handling of rock support and reinforcement elements are such that deterioration with time is minimized<br><br>Method: Sight documentation on recommended storage methods, check storage areas for each element and check for "suitable to use documentation". Refer to MSIR r. 13.8(2)(d)

5.1 Regular geotechnical inspections are made on foot by suitably experienced personnel to detect change in ground stability of the walls and berms and to document the performance of pit walls with time<br><br>Method: Sight inspection records. Refer to MSIR r. 13.8(2)(g).

5.2 Strategies for pit wall monitoring are appropriately matched to the mode and scale of potential failures and can provide suitable information with adequate forewarning<br><br>Method: Interview personnel. Sight analysis of monitoring results (graph, memoranda, etc.), is there evidence of action plans. Refer to MSIR r. 13.8(2)(g).

5.3 The mine has established tolerance limits for various modes of failure which are used to determine the appropriate levels of action<br><br>Method: View slope movement tolerance criteria. Refer to MSIR r. 13.8(1).

5.4 Where appropriate, a seismic monitoring system is installed in a mine where seismic activity causes damage to the pit walls and/or the rock support and reinforcement systems in the mine<br><br>Method: Where relevant, observe seismic monitoring records.

5.5 Geotechnical hazards and monitoring results are effectively and regularly communicated to the workforce (including management)<br><br>Method: Interview personnel. Sight minutes of safety meetings or display of monitoring graphs. Refer to MSIR r. 13.8(1).

5.6 The mine has developed and implemented quality control requirements for each type of rock reinforcement and support element used at the mine<br><br>Method: Sight performance monitoring results. Refer to MSIR r. 13.8(2)(d).

5.7 Groundwater samples are routinely collected and chemically analyzed to determine the potential for corrosion of the rock support and reinforcement system<br><br>Method: Sight water sampling results, check that regular samples are taken and that widespread assessment is made. Refer to MSIR r. 13.8(2)(d).

5.8 Variations to the recommended installation procedures have been discussed according to the formal design strategy and agreed with the supplier prior to their implementation<br><br>Method: Interview design and installation personnel. Sight documentation. Ask about possible variations to the installation procedures. Have these been agreed with the supplier prior to implementation. Refer to MSIR r. 13.8(2)(d).

5.9 The mine has an action plan that is implemented when it is found that quality control results (e.g. the load capacity of the installed rock support and reinforcement system) do not meet the required standard<br><br>Method: Sight testing analysis and evidence of action plans. Confirm that ground control operators are instructed, trained and competent enough to stop their current activity if ground control materials and/or equipment are not to specification. Confirm there is a system in place to upgrade ground support where performance is inadequate, or where ground conditions or mining geometries change. Refer to MSIR r. 13.8(2)(d).

6.1 An on-going record of geotechnical monitoring, with written notes of observations, is maintained, regularly updated and current. A procedure exists where changes in the geotechnical model are identified, or change in pit wall performance noted and relevant changes made to the mine design and GCMP(Ground Control Management Plan)<br><br>Method: Sight GCMP and history of numerical modeling or mine design changes. Refer to MSIR r. 13.8(1).

6.2 The pit wall performance documentation is current<br><br>Method: Check the last modification date on the document. Refer to MSIR r. 13.8 (1).

6.3 The as-mined pit wall geometry is known and ratified against initial wall designs<br><br>Method: View confirmation and redesign plans. Refer to MSIR r. 13.8(1).

6.4 Accurate plans are used to show “as-is” void and pillar geometry of nearby underground mines to confirm design strategies<br><br>Method: Sight current plan database and assessment documentation. Refer to MSIR r. 13.8(3).

6.5 The mine has developed a process whereby any slope failures are back analyzed to re-evaluate initial designs<br><br>Method: Check slope failure documents and back analysis details. Note that it is not always necessary to change the design for each failure. However, the decision must be suitably justified and formally presented. Refer to MSIR r. 13.8(1).

7.1 The workforce receives on the job training and assessment covering the recognition of geotechnical hazards<br><br>Method: Check training modules. Refer to MSIR rr. 4.13 and 13.8(1).

7.2 The workforce receives on the job training and assessment covering general ground awareness when working near drop-offs, e.g. pit bench edges, ore stockpiles<br><br>Method: Review training material for the topics and review attendance lists of the training sessions. Refer to MSIR rr. 4.13, 13.8 (1) and 13.12.

7.3 The workforce receives on the job training and assessment covering general ground awareness when working near pit walls<br><br>Method: Observe training documents and course completion database. Refer to MSIR rr. 4.13, 13.7(5) and 13.9(9).

7.4 The workforce receives on the job training and assessment covering general ground awareness when working where underground voids might exist<br><br>Method: Check training modules. Refer to MSIR rr. 4.13 and 13.8(3).

7.5 The workforce receives on the job training and assessment covering general ground awareness when working on waste dumps<br><br>Method: Check training modules. Refer to MSIR rr. 4.13 and 13.5.

7.6 The workforce receives on the job training and assessment covering the importance of the correct drilling and blasting work procedures<br><br>Method: Check training records, interview relevant personnel in the mine. Refer to MSIR rr. 4.13, 13.8(1) and 13.8(2)(f).

7.7 The workforce receives on the job training and assessment covering general ground awareness with respect to assessing scaling requirements and safe scaling practices<br><br>Method: Check training modules. Refer to MSIR rr. 4.13, 13.9(2) and 13.9(9).

7.8 The workforce receives on the job training and assessment covering the importance of the correct rock reinforcement installation procedures<br><br>Method: Check training records, interview relevant personnel in the mine. Refer to MSIR rr. 4.13, 13.8(2)(d).

7.9 Mine management have procedures for assessing the ongoing competence and performance of relevant mining personnel in : recognising geotechnical hazards, working near drop-offs, working near pit walls, working where underground voids might exist, working on waste dumps, the correct drilling and blasting work procedures, assessing scaling requirements and safe scaling practices and the correct rock reinforcement installation procedures<br><br>Method: Check training records, interview relevant personnel in the mine. Refer to MSIR rr. 4.13 and 13.8(1).