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Forte’s Engineering Team recently gained its newest team member – we are pleased to welcome Tom Kelley! Mr. Kelley’s 40+ years of engineering experience and geotechnical background brings even more diversified expertise to Forte’s portfolio, further allowing us to serve you, our Clients! Read more about Tom's experience and background below: Thomas (Tom) Kelley, PE – Senior Engineer Mr. Kelley has been involved with geotechnical and environmental investigations and design for mining projects, slurry cutoff walls, dam projects, foundations, and waste engineering projects. He has served as the Senior Technical Lead or Reviewer for numerous tailings storage facilities (new, operating, and inactive) and in this role has performed various Engineer of Record duties. His specific mine-related engineering experience includes leading feasibility studies, site investigations, cost estimates, hydrologic and geotechnical analyses, design studies and preparation of construction plans and specifications for both operational mines and reclamation works in the United States, Canada, Mexico, South America, New Zealand, and Southeast Asia. Mr. Kelley's dam engineering experience includes leading feasibility studies, site investigations including subsurface explorations and in-situ testing, and dam design and preparation of construction specifications for both water storage and tailing dams. His slurry cutoff wall and jet grout stabilization experience includes design, providing on-site construction engineering services and post construction performance evaluations for diaphragm cutoff walls and grout stabilization of tailings dam foundations. His foundation engineering experience has included performing site investigations, foundation designs and designing remedial foundation measures.

Enhanced Mining Services Our Mining Team is continuing to grow in 2023 with new additions to the team, Don Hulse and Amanda Irons. This additional experience enhances our Mining Department's technical expertise in a wide variety of services – statistical analysis, block modeling, geometallurgical modeling, and pit optimization. Our group also has extensive experience in drill and blast including blast vibration by buildings, vibration reduction for slope stability, fragmentation prediction, drill to mill improvements, crest blasting, cost reduction, and production improvements. DONALD HULSE - PE, QP Director of Business Development, Mining Projects Don Hulse is a Mining Engineer with over 38 years of experience in the mining industry, including technical and general management, permitting coordination, short- and long-term planning, economic pit limit analysis, pit phase and design, cost estimation and analysis, resource estimation, geostatistics, feasibility studies, and reserve audit. His project experience includes involvement with gold, silver, base metals, and industrial metals in design, analysis, planning and operational control. He has been responsible for coordinating the efforts of a management team through permitting, construction, and initiation of mine operation. As a mine manager, he led a team of employees and contractors through construction and pre-stripping market value of the undeveloped acreage in conjunction with use of the income approach for valuing the producing assets. Don’s project tasks have included site inspection and safety audits, statistical and geostatistical analysis and modeling, resource estimation and classification, mine design and mineral reserve classification, elaboration of operating plans and production scheduling, model reconciliation and optimization studies, budgeting, and cash flow analysis. AMANDA IRONS Senior Resource Geologist Amanda Irons is a Geologist/Engineer with over 10 years of experience in the geoscience sector. She earned a Bachelor’s degree in Geological Engineering in 2013 from Colorado School of Mines, and a Master’s degree in Mineral Exploration with a minor in Mineral & Energy Economics in 2018 also from CSM. Throughout her career, Amanda has held roles as a field geologist, business development geologist, and a resource geologist. She has provided technical assistance and expertise in the areas of geology, engineering, economic analysis, marketing & negotiation agreements. Amanda is highly experienced in 3-dimensional geological modeling in Leapfrog, as well as in mineral resource estimation, domain analysis, and statistical quality control of geological data. She is English-Spanish bilingual.

Coming up next week at SME MINExchange in Salt Lake City – Forte will be presenting on several interesting topics in Mining & Exploration, as well as Plant Design and Heap Leach Recovery Modeling. Read the abstracts below for an overview of these upcoming presentations: Click here to see our company profile on the SME MINExchange website Setting Up and Executing a Trial in Mining Jon Heiner Many trials fail or achieve bias objectives, and even successful trials can end with no approval to change. In my career, I have set up and managed dozens of trials. Some have been successful with no significant issues, while others have gone devastatingly wrong. Some keys to setting up a successful trial are proper planning, communication, clear key performance indicators, understanding of company culture and personality types. The Use of Dynamic Heap Leach Recovery Modeling to Optimize Plant Design and Operation Barry Carlson/Sean Guidi Plant design and operations are key factors to a successful Heap Leach Project. Optimization of the Heap Leach Facility (HLF) and ancillary facilities can mitigate operational downtime and maximize Net Present Value (NPV) for the life of the project. Utilization of dynamic systems models that track key process indicators (KPIs) that relate to heap leach operations give us the opportunity to optimize plant design and operation for a HLF. These models utilize a full mine-to-heap approach to understand how variations in mine plans and HLF operations impact recovery and project NPV. These models incorporate best practices for optimization; evaluating changes of the mine plan, ore placement, changes in PSD, and changes in planned leaching operations. This discussion will focus on the use of dynamic heap leach modeling to improve plant designs by optimizing flow rates, sizing and optimizing the processing facilities, and improving the phasing of capital. Additionally, this will include discussion of optimization of operations for a HLF, including maximizing recovery, maximizing NPV, minimizing liability into closure, optimizing leaching, and reduction of inventory. Drill and Blast Optimization Through an Unbiased Audit Jon Heiner In mining, drilling and blasting seem to be a simple process in an extensive cycle, but their effects are far-reaching. Drill and blast set the pace for digging productivity, truck fill factors, crushing, recovery, maintenance, and so much more. With one process that has such effects on the rest of the value stream, why do we pay so little attention to it? If you could improve this one process, it can enhance multiple downstream processes. Having an unbiased audit is the first step is to better understanding and improving the process. If you will be attending the MINExchange conference, don’t forget to stop by and see the full presentations in-person! Here’s the schedule: We look forward to seeing you there!

In less than two short weeks, Forte Dynamics’ Senior Mining Team will be at ISEE’s 48th Annual Conference in Las Vegas! Come see us at Booth 1403 to learn more about the drill and blast consulting services we offer. Our team has extensive experience that includes vibration control, pattern design, reactive ground, product trials, blast optimization, and blasting next to sensitive infrastructure. Who to look for: Jake Cefalo and Jon Heiner Coming to you in Salt Lake City at MINExchange 2022: Forte Dynamics, Forte Analytical, and Opencontour will all be together under one booth. We have some exciting things planned that you won’t want to miss – live demos, presentations, and more! Who to look for: Barry Carlson, Adam House, Jake Cefalo, Jon Heiner, Devon Whalen, and Sean Guidi Nick Gow, Brittany Garcia, and Jiajia Wu Russ Downer and Maria Echavarria Presentation Schedule: Forte Dynamics is proud to sponsor this year’s Heap Leach Solutions conference! Our team will be presenting abstracts on several topics. More details to come later.

What is the heap leach pad inventory? It is a question that every heap leach operation seeks to answer and to quantify. Heap leach operations yield ranges in recovery relative to placed ounces and recoverable gold. Detailed metallurgical accounting and heap leach models can provide estimates on remaining inventory, similar to the graph below: So, what does each line represent? Total Gold Placed – Fire Assay Grade on the pad Total Extractable Gold – Fire Assay Grade multiplied by ultimate expected recovery from metallurgical test work Extracted Gold – Gold complexed from the ore into solution Recovered Gold – Gold out the bottom of the pad and recovered through the process plant Remaining Extractable Gold – The difference in Total Extractable Gold and Extracted Gold Remaining Recoverable Gold – Total gold remaining for potential recovery, the difference in Total Extractable Gold Placed and Recovered Gold Gold in Solution – Gold that has been complexed but not recovered, the difference in Extracted Gold and Recovered Gold But more importantly, how do we get the remaining inventory? The inventory grows over time as operations progress. Large jumps in the inventory typically occur when issues in operations arise. Short-cycling, double-stacking, high-clay areas leading to poor percolation, poor pH, lime addition issues, and CN issues to name a few. The Remaining Extractable, Remaining Recoverable, and Gold in Solution can be very large numbers depending on the operation. Realizing these ounces is typically very profitable, but can be difficult, and perhaps cost prohibitive. Forte has assisted numerous operations with evaluating the opportunity to recover the inventory from the pad and aided with analysis as to the potential benefit. Methods for recovering this inventory include material re-handling, on/off rest and leaching cycles, and solution wells. Material re-handling can change flow paths and allow for changes in solution to rock contact which can increase recovery, however this is typically cost prohibitive. Rest cycles allow for extraction to continue and can reduce overall solution in the system and is less expensive to implement, however this does not necessarily assist with solution to rock contact at depth for dry areas or areas beneath compacted zones. Solution wells can allow for solution to be introduced in previously dry areas or under-irrigated areas at depth, however depending on the number of wells required and the types of wells, these can be cost prohibitive as well. Forte has found success with utilizing these options for recovering the pad inventory and we've assisted our clients with reducing inventory within the pad while entering into closure operations. Forte has utilized various modeling techniques, coupled with on-site testing programs, to evaluate the opportunities for each site to realize value as pad operations come to an end. We can work with your site team to analyze the opportunity to reduce inventory and realize recovery for heap leach pads as they progress towards closure. Analysis can be conducted to understand residual recovery related to required pumping operations to manage solution on-site. This can assist with profit post mining and stacking operations.

Jake Cefalo, Forte Dynamics, Denver, CO Forte Dynamics’ skilled drill and blast group brings over two decades of operational and technical experience. Our members bring a multitude of services to your drill and blast needs for any project and operation. WE PROVIDE: Blast performance data collection and interpretation, including ore movement, back break, compliance to design, energy distribution, and more. Blast design recommendations to improve fragmentation and blast movement. Open pit pattern design and loading recommendations to achieve vibration limits for underground mines and sensitive infrastructure. Blast records recommendations to improve and understand compliance design vs. actuals in measuring costs of blasts. Operational and technical blast audits and training courses. Reduce costs by measuring production performance and optimizing blast designs. Create long-range drill and blast plans, accounting for rock types, drill performance, estimate cost, and production requirements. Setup of reactive ground testing programs and determine operational practices to reduce possible reactivity incidents. Design and implement crest blasts to protect critical infrastructure and active mining area below. Please contact Jake Cefalo at jcefalo@fortedynamics.com for any questions. Forte Dynamics is a mining and heap leaching consulting firm that brings diverse expertise and decades of experience to your project. We are professional engineers — with special expertise in mining, processing, metallurgy and hydrodynamics — who bring appropriate levels of analysis and pragmatism to every problem. Working as part of your team, we help you analyze the crucial trade offs — technical, financial, regulatory and environmental — that lead to innovative solutions, optimal decisions and improved mining project performance. Find out more at www.fortedynamics.com.

Clint Green, Forte Dynamics, CO, USA CAPITAL COST Capital cost is the biggest differentiator in comparison of the two and in almost every circumstance the VCIC has the advantage. This is due to the reduced footprint and the height of structure and therefore building, if one is required. The barren flow coming from the most elevated tank allows flexibility on the height of the barren tank, which in turn opens up the opportunity to optimize Barren Pump selections. In CIC design, the raising of the barren tank has a knock on effect of raising everything upstream, thereby increasing the capital cost. This includes structural steel for the support of cascading CIC tanks. The VCIC design is self-supported by a concrete foundation, like other conventional tanks. EXECUTION SCHEDULE VCICs are typically fabricated in full (exception of site glass and minor items) and shipped to site. The full VCIC train can be set in place with a crane in fairly short order. This is a significant time savings compared to setting the steel support prior to placing each column. It also eliminates the time spent welding the external launder that often accompanies large cascading columns. OPERATING COSTS Operating costs are very similar. There is an advantage to the VCIC operational cost due to the smaller footprint and heating of the area. This is a larger consideration in cold climate heap leach operations. Included in the operational cost is maintenance, which is similar and requires very little maintenance that requires shutdown or bypassing of the tanks. In the case of the VCIC, the whole train would need to be bypassed if work is required on one tank. While this is a concern, it is one that we discuss in detail with our clients and include in our design to mitigate this risk. The risk is mitigated to a point that operations that have VCIC and CIC on sites do not differentiate between the process when looking at availability, as down time of either is negligible on an annual basis. Process/Recovery The process design is the same for both designs for carbon bed fluidization and adsorption efficiency and therefore recoveries are expected and have shown to be the same. However, projects may choose a 5-stage CIC to reduce capital costs (footprint, building height, structural steel, etc.), while for a much lower cost, a 6-stage VCIC can be implemented and yield higher efficiency by comparison. Forte Dynamics is a mining and heap leaching consulting firm that brings diverse expertise and decades of experience to your project. We are professional engineers — with special expertise in mining, processing, metallurgy and hydrodynamics — who bring appropriate levels of analysis and pragmatism to every problem. Working as part of your team, we help you analyze the crucial trade offs — technical, financial, regulatory and environmental — that lead to innovative solutions, optimal decisions and improved mining project performance. Find out more at www.fortedynamics.com.

Forte Dynamics uses a holistic, systems approach to project optimization by analyzing and understanding the role of each component in the system - from resource modeling through process technology - in the context of maximizing our clients' returns over time. We utilize detailed resource modeling and mine planning tools coupled with detailed metallurgical analysis to evaluate the various trade-offs for the project including comminution and processing. Forte Dynamics uses Opencontour to allow projected recovery to influence cutoff/cutover grades, providing a closed-loop methodology for optimizing the entire mine-to-recovered-metal system. Opencontour tracks individual blocks from the pit to discretized blocks on the heap leach pad with all of the pertinent ore properties, such as lithology and p80, to track recovery through time using detailed leaching hydrodynamics and kinetics. This allows our clients to evaluate risks and dependencies, with sensitivity analyses, to develop a more robust design and confident outcome. Our clients' objectives - whether metal recovery itself or financial results (NPV,IRR) - drive the "one size fits one" optimizations uniquely tailored to each site and situation. Please visit the Forte Dynamics website for more information of contact us by email at service@fortedynamics.com. Forte Dynamics Forte Dynamics is a mining and heap leaching consulting firm that brings diverse expertise and decades of experience to your project. We are professional engineers — with special expertise in mining, processing, metallurgy and hydrodynamics — who bring appropriate levels of analysis and pragmatism to every problem. Working as part of your team, we help you analyze the crucial trade offs — technical, financial, regulatory and environmental — that lead to innovative solutions, optimal decisions and improved mining project performance. Find out more at www.fortedynamics.com.

Brendan Fetter, Forte Dynamics, CO, USA Enhancing Gold Recovery Gold heap leach operations utilize traditional stacking and leaching methods for recovering gold. As these heap leach pads get older, the gold inventory continues to grow, due to dilution through the pad, compaction within the pad impacting hydrodynamics, and reduced leach cycles due to stacking constraints. To reduce this gold inventory, Forte Dynamics found that solution wells are an effective mean for enhancing gold recovery within these heap leach pads. We provide full on-site support for the testing, design, drilling, well completion, leach planning, and permitting. Gravity Solution Wells Forte Dynamics utilizes gravity solution wells as a cost-effective method for enhancing recovery in the heap leach pad. Gravity solution wells do not introduce large amounts of pressure that would mobilize fines where solution is flowing, instead it allows for unsaturated flow within the heap where, previously, solution may not have been able to access. These wells can be drilled vertically or angled to apply solution to the desired location. Samples are taken at intervals for metallurgical testing to create tailored leaching campaigns for each site. injection Low Pressure Solution Wells Another solution well method utilized by Forte Dynamics are low pressure wells. Testing programs can help define the pressure profile required in the solution wells to increase the area of influence without mobilizing fines. Low pressure wells can hasten metal recovery from under-leached ore. The set-up can be reconfigured for lower fluid velocity at the solution introduction zone with a steady increase in the flowrate to increase the area influenced by the wells. The design employed by Forte Dynamics will prevent damage to the heap and will result in no loss in coverage. Other methods have shown to mobilize fines and create no-flow areas within the pad, impacting hydrodynamics and recovery. Please visit the Forte Dynamics website for more information or contact us by email at service@fortedynamics.com. Forte Dynamics Forte Dynamics is a mining and heap leaching consulting firm that brings diverse expertise and decades of experience to your project. We are professional engineers — with special expertise in mining, processing, metallurgy and hydrodynamics — who bring appropriate levels of analysis and pragmatism to every problem. Working as part of your team, we help you analyze the crucial trade offs — technical, financial, regulatory and environmental — that lead to innovative solutions, optimal decisions and improved mining project performance. Find out more at www.fortedynamics.com.

Sean Guidi, Forte Dynamics, CO, USA Brendan Fetter, Forte Dynamics, CO, USA Abstract paper on Heap Leach Facility Modeling from Sean Guidi and Brendan Fetter of Forte Dynamics. Forte Dynamics will be presenting on Optimization and Recovery from Heap Leach Facilities utilizing Dynamic Systems Modeling at the Heap Leach Solutions 2020 conference September 13-15, 2020, in Reno, Nevada (https://www.heapleachsolutions.ca/). ABSTRACT When looking to optimize recovery from Heap Leach Facilities (HLF), it is important to utilize dynamic systems models that track key process indicators (KPIs) related to heap leach operations. These models can be utilized to evaluate multiple scenarios and to optimize the project for recovery or for NPV. These models utilize a full mine-to-heap approach to understand how variations in mine plans and HLF operations impact recovery and project NPV. These models incorporate best practices for optimization; evaluating changes of the mine plan, ore placement, changes in PSD, and changes in planned leaching operations. This discussion will focus on best practices utilizing dynamic systems models for optimization of project using a mine-to-heap modelling approach. Additionally, this will include discussion on integration of operational data for enhanced planning and forecasting of HLFs. Discretized heap leach models have been developed for several sites around the world. These models incorporate metallurgical data, tons and grade, PSD, ore stacking plans, pad geometry, kinetics, and hydrodynamics. The HLF is represented as a discretized matrix with vertical separation, representing lifts, to form spatially discrete cells. Activation of extraction and recovery is based on loading and leaching to allow for simulated growth, compaction, solution movement, and recovery over time. Each discrtized cell is quantified with ore properties and metals content including bulk density, initial moisture content, residual moisture content, metals content, and specific equations for detailing recovery. The model tracks solution movement and recovery of metals as a function of time based on unsaturated flow properties, kinetics dissolution and diffusion rates, and leaching dynamics. These models have been utilized by sites to evaluate the full mine-to-heap approach to assist operations with optimizing project performance. They assist with both short term and long term planning to bring ounces forward and enhance project NPV. They are important tools for trade-off evaluation and optimization of operational performance with respect to HLF recovery. Brief Biography of the Author Sean Guidi is a mechanical engineer with engineering and construction experience in dynamic systems modelling analyses related to heap leach facilities and other mining processes. He also has experience working as a process engineer, performing several models for existing operations to enhance production and analyze processing facilities. This has included optimization of project performance by evaluation various trade-off scenarios. Sean also has experience with development and maintenance of water balance models in GoldSim. Forte Dynamics Forte Dynamics is a mining consultancy firm providing an integrated mine-to-heap approach that looks at the entire heap leach mining process, including design, stacking, leaching operations, and the process plant. The result is project optimization on a much broader scale than has been possible in the past. The improved design, operations, and economics enabled by our approach make Forte Dynamics an essential partner for mining corporations worldwide. Find out more at www.fortedynamics.com.