Portable Light Percussion Drilling: A Practical Solution for Challenging Site Conditions

July 5, 2022   |  

Some geotechnical site investigations face challenging conditions such as poor site access, restrictions on the operation of heavy equipment, and limited budget and time to complete the program. In these situations, the use of portable light percussion drilling systems can be a practical and efficient method for obtaining ground samples. In KCB’s project work at the Fruta Del Norte mine in Los Encuentros, Ecuador, these systems have been an invaluable tool because of their mobility and ease of use.

The Fruta Del Norte mine is located in the province of Zamora, in the jungle region of Ecuador. KCB has been working at the mine since 2009 undertaking site investigations, geotechnical assessments, and feasibility studies at the tailings storage facility (TSF) and Plant Site. The mine is in a densely vegetated jungle where the presence of thick residual soil horizons and high yearly precipitation (3000 mm per year) make the logistics for field programs difficult.

To overcome some of the challenges in recovering soil samples at the project site, the KCB team adopted a portable light percussion drilling system. The system is a portable gas-powered percussion drilling apparatus with a core sampler. It operates by advancing steel gouges and/or core samplers into the ground by a telescopic drilling method, where progressively smaller diameter gouges are driven into the soil. The soils contained in each gouge is sampled through a window in the side of the tube. Depending on the drilling apparatus’s specifications, some have drilling depths of up to 10 m.

Light percussion drilling system - Fruta Del Norte project, Ecuador

Advantages

  • Low cost compared to conventional drilling rigs.
  • Easy transportation and operation.
  • High penetration rates (up to 3 holes of 6 m per day).
  • Good recovery up to 6 m depth.
  • Very good recovery in ‘cohesive’ fine-grained soils.

Disadvantages

  • Disturbance of each sample is unavoidable.
  • Requires a few people to manoeuvre the equipment.
  • Poor recovery of wet coarse-grained soils with the supplied core sampler, and at depths below 6 m.
Categories:   Blog

Decision Analysis: A Structured Approach to Improving Project Success

June 21, 2022   |  

Decisions are a part of our everyday life. They can include a low-stake decision like buying a cup of coffee before your drive into the office, or a high-stake decision like buying a house. As engineering professionals, your project work requires a multitude of decisions and the opinions of stakeholders throughout the process. Decisions made in a project setting often require a more structured approach to produce a rational and auditable methodology for determining a choice between competing options.

A decision analysis process can help build consensus among stakeholders, consider a wide range of options, identify potential risks, and develop a plan with specific actions. There are several that are commonly used in project management including the Kepner-Tregoe method and Multiple Accounts Analysis. The advantage of a decision analysis process is it can bring together informed people in many fields (fields of interest are called accounts) and can include social, environmental, technical, and cost aspects of a project. These fields of interest often have competing requirements and different risk profiles which the process describes in plain language and evaluates from different stakeholder viewpoints, often in a workshop setting.

Define the Problem

The first step when conducting a decision analysis is defining the problem. During this step, you will develop a thorough description of the situation, its purpose, and identify a core team of stakeholders from a variety of fields (geotechnical, environmental, operations, finance, etc.) who can contribute. The core team should determine the purpose of the decision and any constraints that will guide the scope of the process. It is during this step that you will consider multiple criteria, identify the account structure (social, environmental, technical, cost, etc.), and define assumptions.

Establish the Objective

Once you have developed an understanding of the problem, you can establish the objectives of the decision. Start by compiling a list of objectives and divide them into “musts” and “wants”. "Must” objectives are criteria that must be met for an alternative to be successful (e.g. regulatory criteria). “Want” objectives provide the means of differentiating between options (e.g. maximize opportunity to reach passive care) and do not need to be met for an alternative to succeed.

Identify Alternatives

In this step, you will identify alternatives to meet the decision. These can be achieved through a matrix of elements to develop various options which are discussed throughout the process. If any alternatives do not fulfill all the “must” objectives, screen them out.

Engage Stakeholders

Now, compare the alternatives to the defined objectives. (This is typically undertaken in a workshop setting with key stakeholders and a capable facilitator guiding the process.) Rank each alternative based on its ability to achieve the objectives. For this step, alternatives must meet all the “must” objectives and are evaluated against the “want” objectives. Assess your results by conducting sensitivity analyses and a risk assessment to reduce the overall risk to as minimal as possible.

Make your Decision

Decide on an alternative based on how it ranks above other alternatives, its costs, and risks. Once a decision has been made, develop an action plan, documenting the approach and rationale of the decision, to move the project forward. This step usually includes a forward high-level work plan for the project.

Tips when conducting a decision analysis:

  • Be clear on the situation appraisal and problem analysis prior to undertaking the decision analysis.
  • Have the right people in the room to make decisions. Identify and include key stakeholders to increase the success of the decision analysis process.
  • Achieve consensus at each step.
  • An objective framing workshop is a useful way to engage decision makers and identify policy, strategic and tactical objectives.
  • Characterize each alternative with a supporting body of knowledge enough to compare each option without prior judgement.
  • It can be as simple or complicated as it needs to be. But do not over-complicate. Not all the answers are needed to make an informed decision.
Categories:   Blog

Employee Spotlight – Matthew Forbes

May 18, 2022   |  

Matthew Forbes is a Hydrogeochemist based in our Brisbane office.

1. What does a typical day look like for you?

A normal workday involves getting up to walk the dog, drinking some coffee, and then riding my bike to work. However, during the floods, my bike was stolen and the office was flooded so that is not so normal now. Nowadays, I like to get into the water so I try to swim at lunchtime at Musgrave Park at least once a week. After work, more dog walking, dinner, a beer, and some TV. On weekends I like to head to the beach or the pool or head to Bunnings and buy useless things for my herb and veggie garden.

2. What has been the most fulfilling part about your role?

Using my previous experiences, which are outside the consulting realm, to help provide solid scientific answers to project questions.

3. What is something you find challenging about your role?

Learning about the mindset of industry clients, in terms of understanding what they really want and how much they are willing to pay to get it.

4. What is your biggest achievement?

The first is successfully running a multi-million biogeochemical laboratory at Stanford University. The second is publishing a paper on the global carbon cycle that now has been cited in over 500 subsequent publications.

5. What advice would you give someone pursuing a career in your field?

Learn to plan, because as they say, failing to plan is planning to fail. Be happy but humble about your professional achievements.

6. What qualities do you think make a good scientist?

Experience makes a good scientist, a good geoscientist, and overall a good consultant. I have been very lucky over the last 20 years to work in the fields of hydrogeology, geomorphology, quaternary climate science, oceanography, and soil science across state government, CSRIO, commercial start-ups, world-leading university research institutions, national research centres, and now industries with KCB. All these experiences make me the professional I am now and gave me the skills I bring to KCB.

7. What is your favourite thing about working at KCB?

Diversity of the tasks and challenges and the places that you go to, that you would have not never otherwise.

Categories:   Blog

Selecting a Gridding Algorithm for Geology or Ground Models

May 10, 2022   |  

Geology or ground models are critical elements of engineering or geoscience design. They define the interaction between the built and natural environments.

The built or engineering environment is two-dimensional, consisting of straight lines and formed curves. It is a consistent, patterned design, that is regular and conforms to mathematical summation.

The natural environment (geology) is three-dimensional and inconsistent in form and continuity; variation and change are everywhere and affect every component of the system. Randomness does not work well with engineering design, and order and simplicity do not usually apply to geology.

However, great success in modelling the natural environment occurs when these aspects are integrated in an efficient and defensible manner.

Gridding algorithms are mathematical processes that read irregularly distributed data and convert these into a regularly spaced array. In simpler terms, the process converts drill hole contacts to a format that can be converted to wireframes, geological models or block models, which in turn inform many of our analyses and interpretations.

It is our role as professionals to select an appropriate algorithm that balances aesthetic visualization with the defensible representation of the data. When the wrong algorithm is selected this results in unrealistic data construction that is difficult to identify and is time-consuming and frustrating to correct.

Algorithm Considerations

The main considerations in selecting an interpolation algorithm include:
  • What is the density and distribution of drill control?
  • Do you expect regularity in the surfaces, typical with sedimentary units?
  • Are artificially constructed troughs and peaks in synthetic data between drill holes acceptable?
  • Does generated data need to extend beyond the lateral extents of the base information?
  • Is there geological skew that needs to be considered (i.e. anisotropy)?
  • Are there other geological structures or boundaries?
  • Applying Common Algorithms to Geological Models

    The following drill hole data (left) was contoured using three algorithm methods: triangulation, minimum curvature and kriging.




    Triangulation

    The triangulation algorithm uses lines to create triangles between data points. Triangulation results are blocky and abrupt, yet often best reproduce the original data.



    Mininum Curvature

    Widely used in earth sciences, minimum curvature generates a smooth interpolated surface from the data points. Minimum curvature results honour the original data while achieving smoothed contours.



    Kriging

    Kriging is a geostatistical gridding method used to express trends suggested in the data. Kriging results include troughs and peaks and smooths the areas of limited data. Where base data is sparse or geological contacts are abrupt, kriging can skew the data.






    Use the following principles when selecting a gridding algorithm:
  • Honour the data before aesthetics – it is easier to defend an ugly map than a wrong map.
  • Interrogate the results so that you know the potential error introduced by the algorithm. It has consequences to your design, so understand it!
  • Think about the output before gridding – interpretation must drive this process, not mathematics or visually-pleasing output.
  • Recommendation

    As a starting point, the minimum curvature algorithm is a good all-rounder. Apply a moderate grid density, by aiming initially for 10,000 nodes (or 100 x 100). Always compare the constructed surface with the original data by running a “residuals check” to assess the algorithm’s performance. In areas of sparse data, create sections or view the data to check for algorithm-generated troughs or peaks.

    Categories:   Blog

    Employee Spotlight – Jim Heaslop

    February 8, 2022   |  

    Jim Heaslop is a Senior Surface Water Engineer and Associate based in our Brisbane office.

    He joined our Brisbane team in 2018. Jim has 18 years of experience in the field of water engineering and is a Chartered Professional Civil Engineer and Registered Professional Engineer of Queensland (RPEQ).

    Jim is experienced in managing water engineering and water resource projects in the mining and infrastructure sectors. His recent work has included the development and use of dynamic water balance models to define the performance of site water management systems.

    1. What does a typical day look like for you?

    Up at 5am, brew a coffee, eat breakfast and read the news.
    At work by 7am, and usually leave sometime between 5pm and 6pm.
    After work: Running training (with a squad of high school runners). It makes me feel young until the session starts, then they make me feel old and slow.
    Home to cook dinner and catch up with my wife and step kids. In bed between 9pm and 11pm - 9pm is a goal, 11pm is often the reality!

    2. What has been the most fulfilling part about your role?

    Helping others to be successful and excel at what they do.

    3. What is something you find challenging about your role?

    Managing my time to fit in everything I want to do/help with.

    4. What is your biggest achievement?

    Sometimes it feels like getting out of bed is my biggest achievement, and at least once I have done it, I have achieved something for the day!

    5. What advice would you give someone pursuing a career in your field?

    Reward does not come on credit. You need to work hard and invest in your career. Have faith that in time, the return on your investment will come. It may not come as quickly as you want, but your career is measured in decades, not months or years. So don’t be in a rush, you have to enjoy the journey.

    6. What qualities do you think make a good engineer?

    Not losing sight of why we are doing something. Sometimes we focus on the how and what, but forget to ask why. When we ask why, it can open up a range other potential outcomes.

    7. What is your favourite thing about working at KCB?

    The people. It is as simple as that.

    Categories:   Blog

    Drone and Remote Sensing Capabilities at KCB

    March 5, 2021   |  

    Over the past three years, KCB has been expanding our implementation of drone and remote sensing technologies to improve project deliverables, help clients and stakeholders visualize sites, and identify potential site issues from different vantage points. Currently, we are operating drones for a variety of projects and clients, from railways to roads and highways, to hydroelectric facilities.

    Drone Mapping

    Since 2018 KCB has been using two drones, the DJI Phantom 4 Pro, and the DJI Mavic Pro with experienced and licensed drone operators. Both drones feature 20 megapixel cameras capable of capturing 4k video with 30 minutes of flight time on a single battery.

    DJI Drones – Phantom 4 Pro (Left) Mavic Pro (Right)

    These drones combined with KCB’s suite of photogrammetry software, ArcGIS Drone2Map, allow us to process the data and deliver the output to clients efficiently through software that is widely used in the industry without the need to convert file types. This technology allows the creation of both 2D and 3D models of project sites which can be georeferenced using the drones' built-in GPS, or with Ground Control Points (GCPs) for improved accuracy.

    3D Photogrammetry Model of Railway Bridge

    KCB has also implemented photogrammetry rock slope mapping using 3DM Analyst software with terrestrial and aerial drone photos. This has decreased KCB’s time spent in the field and allowed us to remotely collect information of areas which might otherwise be unsafe to map. Combining this tool with traditional field mapping techniques allows for the collection of much larger data sets which can be analyzed by a variety of geotechnical software.

    Project Examples

    Rock Face Mapping

    KCB has conducted several photogrammetry rock slope mapping projects for transportation and hydroelectric clients. Photogrammetry rock slope mapping has allowed us to map areas which would otherwise require specialized training to access or would be too dangerous to access by people, including cliff faces or areas made inaccessible by rockfall hazard. Additionally, being able to combine photogrammetry mapping with traditional field mapping allows for a collection of larger data sets and a calibration tool for the photogrammetry models. KCB continues to push the capabilities of these mapping techniques and photogrammetry mapping has become an important part of rock slope assessments on projects.

    Rock face mapping using 3DM Analyst

    Construction Monitoring and Change Detection

    The ability to conduct change detection by flying an area quickly and repeatedly allows KCB to help track project schedules and volumes during construction. This allows clients to obtain visual checks on construction progress without having to travel to the site, and assists in the QA process. This technology can also be used in monitoring geohazards, such as landslides, and track movement of surfaces over an extended time period. For the application of landslides, understanding the active areas of movement help our engineers focus where mitigation measures may be required.

    Volumetric Change Detection for Linear Infrastructure Construction

    Flying into the Future

    In 2021, KCB has expanded our drone and remote sensing capabilities with the acquisition of the new DJI Matrice 210 RTK V2 along with a GNSS base station for improved accuracy without needing additional surveying for ground control points. With these increased accuracies and capabilities KCB is poised to improve on existing services provided to clients, including increased accuracy for change detection for volumetric calculation and geohazard monitoring and assessments. Additionally, our team is continually looking to add new services and capabilities for our clients based on their feedback and project needs.

    RTK Communication Lines

    Categories:   Blog

    Lessons learned during the COVID-19 pandemic

    October 21, 2020   |  

    Engineering consulting sector adapts to the biggest challenge of a generation Every aspect of society and our everyday lives has been disrupted by the COVID-19 pandemic. In March 2020, the unthinkable happened – whole countries shut down and everyone, apart from frontline and essential workers, hunkered down at home. As an essential service, we in the consulting engineering sector also took our work home to keep our portfolio of infrastructure, mining, energy and other projects moving ahead. Over the past several months, following a crash course in adaptability, we’ve learned some key lessons about our industry. Two lessons stand out. The New Duty of Care

    Our industry’s new duty of care extends to preventing the spread of infection to others while serving our clients. Our initial reaction was for everyone to work from home, but we soon realized it wasn’t always practical or efficient. Some employees adapted to their home situation with ease, but many didn’t have enough space or connectivity to work from home effectively. It was also difficult for new employees to make new acquaintances, and for many of our projects, we still had to travel and work in the field.

    Almost immediately, we started to plan for the safe return to our workplaces. We carefully assessed our offices and field sites, and had to re-think project delivery to our clients, starting with do we absolutely need to travel and how can we do this differently? We prepared plans for travelling safely, supplied new PPE, developed new communication protocols, and planned emergency response measures if someone became infected.

    We dedicated lots of time to develop and communicate safety plans with our employees and clients. During the pandemic, we must not underestimate how long it takes to meet our new duty of care.

    The New Workplace

    Returning to our workplaces was the first (and perhaps easier) step. Once back, we realized that our collective daily habits had to change, and that it could potentially last for years rather than months. The new workplace is one of physical distancing and sanitization, and continual reinforcement of the rules. We now speak a new language - one that describes testing methods, infection rates and the difference between quarantine and self-isolation. And as we move differently around the office, we’ve learned a new dance of maneuvers around the water cooler!

    Although the engineering consulting industry has always had a strong culture of safety, we have never faced a pandemic such as this. Post-pandemic safety cultures must now include new levels of communication, hygiene and health monitoring; and the post-pandemic C-suite must be bolstered by corporate medical professionals or a healthcare team.

    The COVID-19 pandemic has reinforced the notion that our industry is founded on people. It may seem obvious, but we often focus too hard on the projects and lose sight of the clients, contractors, engineers and geoscientists that make the projects work. Our reputation for integrity and passion for our craft, will serve us well as we adapt to these new challenges.

    Categories:   Blog

    Use of Drones at Harmony’s Hidden Valley Mine

    July 15, 2020   |  

    KCB regularly uses a light-weight drone to collect high-quality images and videos from elevated platforms for routine embankment construction monitoring activities at the Hidden Valley mine site in Papua New Guinea. The drone, which belongs to our client, Harmony subsidiary Morobe Consolidated Goldfields Limited, provides a number of benefits to KCB field staff working in remote locations of the mine site, such as the Hidden Valley tailings storage facility (TSF), including:

    • Improved confidence in assessing earthworks compliance against design, based on visual evidence;
    • Safer monitoring opportunities where field staff access is constrained by topographical or other reasons;
    • The ability to confirm ground conditions and earthwork construction activity in remote areas before attempting to access such areas which can be cumbersome and time consuming;
    • Rapid visual assessment of key areas following large rainfall or earthquake events; and,
    • Improved monitoring ability as large areas can be covered quickly, and data can be compared where repetitive data collection exists.
    Hamata TSF at Hidden Valley with the Main Dam in the foreground
    Hamata TSF at Hidden Valley with the Main Dam in the foreground

    KCB also uses the drone field data to integrate with LiDAR and survey data collected by a survey drone. The survey drone is a larger unit than the equipment used by KCB for routine monitoring because it is required to carry a larger payload at altitudes of 2,000-2,500 metres above sea-level and be able to collect field data for longer periods of time.

    KCB has experienced a number of challenges using the small drone at the Hidden Valley mine site, some of them unexpected:

    • The light-weight drone performs remarkably well in moderate wind and light rainfall. However, it is always preferable to use this equipment in fine weather conditions as platform stability is linked to data quality;
    • When trespassers are unexpectedly encountered, they have used slingshots to try to chase the drones away;
    • Birds of prey breeding near the TSF are aggressive and territorial, and it is not uncommon for the kites on site to attack the drone if it flies into their territory; and,
    • The drone is small and white and is surprisingly difficult to see in the distance, especially under overcast conditions. This is also the case when the drone is used at night. The “return home” function provides a lot of confidence to recover the instrument in such situations.
    Categories:   Blog

    History of Tailings Dam Design

    May 19, 2020   |  

    Tailings dam construction has evolved and improved over the past several decades. Klohn Crippen Berger (and its predecessor companies) helped to revolutionize the design of modern tailings storage facilities 50 years ago, and our engineering approach continues to be the hallmark of international practice. Today, we provide solutions for some of the largest, technically challenging tailings storage facilities in the world.

    In the early days, tailings were simply disposed of in local rivers and streams. It was only in the 1960s when the first tailings dams were built. Today, other technologies such as filtered tailings and co-disposal are being used around the world. Here is a timeline of tailings dam construction, as well as a brief overview of the three main types of tailings dam designs.

    Early days – pre-1900

    Historically, the only option for tailings storage was to deal with a tailings slurry. Tailings were disposed of in the most convenient manner, such as in rivers and streams. By about 1930, this type of tailings disposal was stopped in the western world, creating the first benchmark regulations on mine waste management. In a few areas of the world, tailings are still disposed of in waterways, especially areas that have high rainfall and steep, unstable terrain. However, this method of disposal is no longer common practice, mainly because of environmental concerns.

    Pre-1960s

    Up until the 1960s, tailings dam designs either used the upstream dam construction method or conventional water storage dam designs to contain the tailings. An early photo of upstream dam construction is shown in Figure 1.

    Figure 1: Upstream dam construction, British Columbia (early 1960s)
    Figure 1: Upstream dam construction, British Columbia (early 1960s)
    (Image source: A Dedicated Team, Leonoff, 1994)

    1960s

    Cycloning of tailings was developed in the 1960s and continues to be a major component of tailings dams (McLeod and Bjelkevik, 2017). In 1962, cycloned tailings for dam construction was first adopted on the Zambian Copperbelt, with the construction of the Lubengele Dam.

    In the mid 1960s, Earle Klohn, one of the founders of Klohn Crippen Berger, pioneered the design of centerline cycloned sand dams (see Figure 2 below). This was one of the first engineered tailings dam designs in the world. The design was based on the sound principles of soil mechanics and still, to this day, meets seismic criteria for high dams. The Brenda Mine tailings dam in British Columbia is the first centerline cycloned sand dam in the world (see Figure 3 below).

    Figure 2: Centerline cycloned sand dam – L-L Dam at Highland Valley Copper
    Figure 2: Centerline cycloned sand dam – L-L Dam at Highland Valley Copper
    Figure 3: Brenda Mine centerline cycloned sand dam
    Figure 3: Brenda Mine centerline cycloned sand dam
    (Image source: A Dedicated Team, Leonoff, 1994)

    In an almost prescient quotation, Earle Klohn stated the following in an address to the University of Missouri in 1977:

    “There would appear to be no doubt but that in the very near future, all tailings dams will be designed and constructed using sound engineering principles based on conventional water storage dam design technology. Moreover, the design and construction of tailings dams will be closely controlled by both state and federal agencies. The added cost associated with satisfying such regulations, must, in the future, be considered as part of the cost of developing the mine.” (McLeod et al. 2015)

    1970s

    During the 1970s, the number of tailings dams in Canada and worldwide started to significantly increase with the expansion of the mining industry. The heights of tailings dams started to exceed 300 m.

    The upstream method of tailings dam construction started to be replaced by the centerline and downstream methods “using cyclone sand embankments, blanketed upstream by spigotted slimes” (Klohn & Maartman, 1972). Downstream and centerline methods resulted in safer tailings dams, especially in seismically active regions. In addition, the mining industry and government regulators were becoming more aware of the need for better and safer tailings dams “to meet basic requirements of safety and pollution control” (Klohn & Maartman, 1972).

    1980s and 1990s

    The use of filtered tailings became more popular in the 1980s. However, significant equipment and operational costs (mainly power consumption) made the filtering of tailings not feasible for most operations (McLeod and Bjelkevik, 2017). With improvements in the efficiency of filtering equipment, the interest towards tailings filtering has increased in recent years.

    Thickening has been used to improve water recovery from tailings streams since the mid-1990s. Thickening the tailings slurry as part of the process plant operation using conventional thickeners has become a common practice over the last few decades (McLeod and Bjelkevik, 2017).

    2000s

    The recent practice of sulphide separation with a flotation circuit in the process plant can produce a tailings product with a low acid rock drainage potential (McLeod and Bjelkevik, 2017). Co-disposal, the placement of acidic mine waste rock with tailings, has gained increased acceptance. Integration of tailings with mine waste rock is important and can be used to reduce costs and risks. Other technologies reduce evaporation losses, for example the use of cells in arid climates to limit the evaporation losses from the wetted beach surfaces (McLeod and Bjelkevik, 2017).

    Types of Tailings Dam Designs

    Upstream

    Upstream construction involves a “starter” dyke which is raised as the pond is filled. The tailings are discharged by spigotting from the top of the starter dyke.

    Figure 4: Upstream constructed dam
    Figure 4: Upstream constructed dam

    Downstream

    Earle Klohn (1971) mentioned that engineering knowledge and experience must be blended with mining operators’ knowledge to develop economically feasible solutions. “One of the first results of blending of knowledge was the development of the downstream method of dam building” (Klohn, 1971).

    A downstream dam is built with sand fill, usually separated from tailings by cycloning. No tailings are mixed with the sand dam, as the dam is built in the downstream direction.

    Figure 5: Downstream constructed dam
    Figure 5: Downstream constructed dam

    Centerline

    Centerline dams are a variation of the downstream dam. In this case the central core zone is supported by the tailings and a localized zone of fill is placed on top of the tailings (McLeod and Bjelkevik, 2017).

    Figure 6: Centerline constructed dam
    Figure 6: Centerline constructed dam

    References:

    Klohn, E.J. 1971. “Design and Construction of Tailings Dams”. Presented at the Annual Western Meeting of the CIM, October 1971, Vancouver BC, CIM Transactions volume LXXV, pp. 50-66, 1972

    Klohn & Maartman, 1972. “Construction of Sound Tailings Dams by Cycloning and Spigotting,” in Proceedings of the 1st International Tailing Symposium, October 31-November 3, 1972. Tucson, Arizona.

    McLeod, H.N., B.D. Watts and H.D. Plewes. 2015. "Best Practices in Tailings Dam Design," in CIM 2015 Convention, Montreal, QC, May 10-13.

    Leonoff, C. 1994. A Dedicated Team: Klohn Leonoff Consulting Engineers 1951-1991. Richmond, BC: Klohn Leonoff Ltd.

    McLeod, H. and A. Bjelkevik. 2017. "Tailings Dam Design: Technology Update (ICOLD Bulletin)," in Proceedings of the 85th Annual Meeting of International Commission on Large Dams, July 3-7, 2017. Prague, Czech Republic: Czech National Committee on Large Dams.

    Tailings.info http://www.tailings.info/basics/history.htm. Jon Engels

    Wikipedia. https://en.wikipedia.org/wiki/Tailings

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    Categories:   Blog

    Klohn Crippen Berger Participates in Consultation on Draft Global Tailings Standard

    February 18, 2020   |  

    An initiative to draft a Global Tailings Standard wrapped up its public consultation phase recently and Klohn Crippen Berger was among the stakeholders to submit feedback to the draft guidelines.

    The standards are being developed by the Global Tailings Review, a joint effort between the International Council on Mining & Metals (ICMM), the UN Environment Programme, and Principles for Responsible Investment.

    The Review was convened following the failure of the tailings storage facility at the Córrego do Feijão iron ore mine, near Brumadinho, Brazil, in January 2019. It aims to establish a standard for the construction, operation, and management of tailings facilities worldwide.

    Specifically, the Review has three main goals for its final Standard:

    • A global and transparent consequence-based tailings facility classification system;
    • Requirements for emergency planning and preparedness; and
    • A system for credible and independent assurance of tailings facilities.

    The draft Standard is divided into six subject areas, each with a set of requirements. As described by the ICMM, the subject areas are as follows:

    • Knowledge base requires mine operators to develop knowledge about the social, economic, and environmental context of a proposed or existing tailings facility.
    • Affected communities focuses on the people living and working nearby. It requires human rights due diligence and meaningful engagement of project-affected people.
    • Design, construction, operation and monitoring of tailings facilities aims to review technical aspects of tailings facilities.
    • Management and governance focuses on related key roles, essential systems and critical processes.
    • Emergency response and long-term recovery covers emergency preparedness and response in the event of a disaster, the reestablishment of ecosystems, and the long-term recovery of affected communities.
    • Public disclosure and access to information requires public access to information about tailings facilities in order for all stakeholders to be informed of the risks and impacts, management and mitigation plans, and performance monitoring.

    The Review will evaluate current best practices in the mining industry and, in addition to evidence and lessons learned from Brumadinho, it will consider findings from tailings facility failures at Mariana in 2015, and Mount Polley in 2014.

    The Review held in-country consultations throughout November and December in Kazakhstan, China, Chile, Ghana, South Africa, and Australia.

    The final Standard and accompanying recommendations — supporting the Standard and outlining how it is to be implemented — are to be published later in 2020. Along with the Standard, the Global Tailings Review will publish a consultation report reflecting the feedback, key themes, and ideas submitted by different stakeholder groups.

    Following publication of the final Standard, all 27 ICMM member companies are expected to commit to its implementation. Thirty-six exploration and mining industry associations and commodity groups also belong to the ICMM.

    Download the draft Global Tailings Standard.

    Watch a webinar on the technical and environmental/social governance aspects of the draft standard.
    Categories:   Blog