1 CARRYBACK: PRELIMINARY STUDY OF MITIGATION MEASURES TO REDUCE ADHESION OF BULK MATERIALS TO CONTAINERS IN COLD WEATHER R E P O R T Bulk Cargo Carryback – Thompson, Manitoba & Region Submitted by: Tim Gibson, Project Lead Subzero North 1 Airport Road Thompson, Manitoba R8N 1M9 (204) 677-0720 DISCLAIMER This report reflects the views of the authors only and does not reflect the views or policies of Transport Canada. Neither Transport Canada, nor its employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy or completeness of any information contained in this report, or process described herein, and assumes no responsibility for anyone’s use of the information. Transport Canada is not responsible for errors or omissions in this report and makes no representations as to the accuracy or completeness of the information. Transport Canada does not endorse products or companies. Reference in this report to any specific commercial products, process, or service by trade name, trademark, manufacturer, or otherwise, does not constitute or imply its endorsement, recommendation, or favoring by Transport Canada and shall not be used for advertising or service endorsement purposes. Trade or company names appear in this report only because they are essential to the objectives of the report. References and hyperlinks to external web sites do not constitute endorsement by Transport Canada of the linked web sites, or the information, products or services contained therein. Transport Canada does not exercise any editorial control over the information you may find at these locations. CONTENTS 1. INTRODUCTION – CARRYBACK…………….4 2. RESEARCH………………………………………….........7 2.3.1 LOAD BALANCING………………………………………………………..11 2.6.1 SUSPENDED DUMP BODY…………………………………..12 2.7.1 CLEANING CONTACT SURFACES……………………………………...14 3 PROJECT METHODOLOGY…………….…..18 4 PROJECT ANALYSIS AND FINDINGS..21 REFERENCES……………………………………………..32 4 Komatsu 930 Haul Truck - Iron Ore Mine in Labrador Feb. 2006 - Carryback estimated at 25 tons in a single day. 1. INTRODUCTION - CARRYBACK ‘Carryback’ is the term commonly used to describe the phenomenon where bulk materials stick to the inside of containers when they are being unloaded by trucks and railcars. For instance, think of snow sticking to a shovel, or soil sticking to the inside of a wheelbarrow – but on an industrial scale. This is an issue that affects operations around the world and varies in severity based on variables such as ambient air temperature, payload moisture content and chemistry, size of payload, age, type of transport devices, compaction, and particle size. Given the size of the trucks and railcars, and the fact that there are not typically ‘observers’ overseeing each dump, the amount of carryback in the loads usually isn’t known until weight measurement systems are implemented to track this inefficiency. Ultimately, these inefficiencies have very real financial repercussions, as trucks and railcars operate at less than full capacity, requiring additional trips to fill or unload the materials they’re carrying and reducing capacity for long-haul deliveries. 5 Responsibility for carryback and its impacts is not consistent across industries and tends to be based largely on geography and location, but generally the onus falls on Operators to develop Standard Operating Procedures (SOPs) for mitigation. Because there are no broad industry guidelines, these SOPs can introduce unsafe and inefficient operations as they can lead to increased safety risks, production losses, increased greenhouse gas (GHG) emissions, and less innovation in overall design options. With its northern location, robust infrastructure, relevant industry activities, and long periods of cold weather, Thompson is ideally suited to conduct these tests. At the heart of the continent, Thompson is accessible by air, road, and rail from Manitoba’s capital city, Winnipeg, and experiences winters with more than 200 days at 0°C or lower. Location of Thompson, Manitoba 6 1.1 PROJECT OVERVIEW Objectives Better understand the current state of carryback in the transportation of resources such as mined ores and similar materials, and the effect it has on operational productivity and cost-efficiency. Identify various mitigation practices that currently exist today, particularly in cold climate conditions where carryback has a significant impact. Conduct field trial experiments to establish the potential effectiveness of suitable mitigation measures. Field trials were supported by a review of available online studies, and further supplemented with the help of a team of participating subject matter experts. These experts were able to provide specific and highly relevant examples of current practices and recent trends sought by industry. The team included: Transportation companies in Thompson, Flin Flon, and Snow Lake, Manitoba that are contracted to haul concentrate from various mills to transfer points for varying upgrades. Biogard Release Agent and Distributor – Moffatt Supply Inc. in Thompson Manitoba, who assisted in field trials, truck preparation, and data collection. Biogard Inc. the spray release agent used in this research offered examples of use in other Canadian Operations of similar latitude and bulk rail challenges. Suspended Dump Body Manufacturer – Duratray NA Inc., supplied as needed (other options available) to reduce carryback with ever decreasing payload options, for mining on-highway and bulk rail options. For example, there are rock boxes approved for/by the OEM company, such as Komatsu. Mining companies in Thompson, Flin Flon, and Snow Lake, Manitoba assisted with current state awareness of carryback levels and research trials; this included mining and production support expertise to ensure the release agent would not negatively impact downstream upgrading. Additionally, some heavy construction trucks were observed in a reclamation and sand and gravel operation in Fox Lake north of Thompson. 7 2. RESEARCH It must be noted that products and strategies to effectively deal with carryback are considered by many in the industry to be a competitive advantage, and sharing their protocols may also reveal sensitive safety concerns. This creates a reluctance on the part of some to openly share their information. Where online studies were available, they were reviewed based on the following criteria: • General causes of carryback • Observation and measurements methods • Mitigation opportunities and strategies 8 2.1 SOURCES UTILIZED FOR RESEARCH Richard Dixon – Research and Academic Coordinator – Athabasca University, Alberta Professor (previous) University of Alberta – BUEC 663 Natural Resources and Energy Capstone MBA Program - evaluation of Capstone Paper titled: Mining Inefficiency – Carryback; An Oilsands Journey Towards Improved Safety, Cost, and Environmental Stewardship (2013). The report highlights the existence of carryback and various mitigation strategies, and the benefits of using Biogard. Derek Bam - Operating Engineers Training Institute of Manitoba (OETIM) Field Operations - Training Operators (aware of issue up front during training) ‘Phenomenon is real and is a combination of many things; product application, weather, and combinations of materials, including mechanical configurations (heated box etc.)’. Derek stressed the importance of proper training and safety protocols with any kind of mechanical/manual removal of carryback. There is the potential for thousands of pounds of stuck material to be dislodged out of the back of a truck, creating a very dangerous situation. Water-Mediated Adhesion of Oil Sands on Solid Surfaces at Low Temperature (Yang, 2022) - is specific to Canadian Oil Sands Operations and it explains moisture content and its impact on carryback. Yang looked at adhesion of oil sands on solid surfaces at low temperatures. By measuring adhesion and water content in oil sands he was able to demonstrate that adhesion strength of oil sands increased linearly on steel and rubber surfaces with an increase in the water content. His conclusions broadly provide insights into anti-freezing approaches to other wet granular materials (i.e., application of adhesion materials lessens adhesion/carryback). 9 2.2 A TESTIMONIAL Ron Doucet, a P. Eng. with 25 years mining and railway experience currently employed at Ryke Consulting provided comments on the phenomena. He observed first-hand the impacts of carryback on rail line safety, reliability, and costs in Labrador. His comments include: ‘From a reliability standpoint, which includes ensuring that equipment performs safely and at desired levels, carryback had an excessive negative impact on the railway. In my experience, carryback on the railway: Decreased the amount of ore being transported as ore was being carried back to the loading point; as this was a bottleneck process, the effects were not only substantial, but also unrecoverable. Caused the ore cars to carry back ore in an off-center position. This greatly increased the chance of derailment, and the cars had to be cleaned to address this. The time to clean the ore cars further decreased unrecoverable production capacity. As you can imagine, a derailment itself has significant safety and operational consequences and the recovery is a hazardous job.’ Example of off-center load in truck; minepayloadtechnologies.com 10 2.3 CAUSES OF CARRYBACK Causes of carryback vary and factors typically include load density, moisture content, temperature, compaction, shock of load/unload, and travel duration. The severity of adhesion/carryback increases most significantly when dealing with small particle sizes in wet and cold conditions. The following chart highlights the expected ‘carryback curve’ a typical Mining Operator may experience, and the months when this phenomenon is most impactful. From May through November the carryback effect is considerably less than in the colder months from December through April. Typical Carryback Curve – Seasonal Losses 100 ton payload Iron Ore Mine Labrador – vs Seasonal Actual Payload Author Tim Gibson - MBA BUEC 663 Capstone 2013 The pink horizontal line in the carryback curve above represents the designed capacity of the ore cars, while the curved blue line represents the actual capacity achieved each month. This kind of carryback curve exists to some degree for almost all bulk transport and modes of transportation. 10 11 2.3.1 LOAD BALANCING For rail cars, carryback can create unsafe mobility conditions. The carryback may be unevenly distributed inside the rail car, creating an unbalanced load that can increase the chances of derailment, and the possible misalignment of tracks, particularly during the spring and fall freeze/thaw cycles. 2.4 OBSERVATION & MEASUREMENT METHODS Observation is needed to determine the size and impact of the carryback problem and the opportunity to mitigate losses of cargo payloads. This observation can be as simple as visual inspections or conducted with the use of scales as an indirect nonvisual method. There are ever-increasingly sophisticated methods that involve real-time data collection, and many of these are becoming more economical over time. The Commonwealth Scientific and Industrial Research Organization (CSIRO) has developed and implemented an electronic Remnant Carryback Detection (RCD) system. In real time, it can detect carryback and trigger operational interventions. Integrating an RCD system into a plant control system allows for interventions as needed. This is accomplished in the Queensland Coal mining operations application by installing: • Two 2D laser scanners mounted above the rail line. • An acquisition and analysis computer housed within the dump station control room Online software for data acquisition and storage. • Offline analysis software for summarizing the results (CSIRO, 2021) Similar to CSIRO, Knights is a subject matter expert (SME) explores the economic benefits of installing an electronic Load Volume Scanner (LVS) system to manage payload and carryback. In his study, he analyzed a gold mine in Central Queensland, and found 62% of all haul truck cycles had excess carryback, which was deemed as more than 0.4 tons per cycle, amounting to 61,000 tons per year. They installed the LVS system to manage payload and optimize fuel consumption and concluded that a 10% increase in load volumes could be achieved, subject to both payload and particle size distribution being optimized (Knights, 2023). 12 2.5 MITIGATION OPTIONS & STRATEGIES Various options exist for the unique circumstances that present themselves to Operators. The first step is to fully understand the specific nature of the problem, and if possible, exactly what is causing it. This typically requires some form of intentional, measurable analysis. Once this is known, suitable options can be evaluated to determine the best plan for implementation. The more data that is accumulated, the better the understanding of carryback costs, and the benefits and risks associated with each mitigation option will be easier to evaluate. There is a range of options and associated costs that exist, such as clean at specific intervals, install modified bulk carrier rock boxes, provide a barrier spray release agent, provide engineered solutions (poly bags, flaps, or mechanical devices). 2.6 MITIGATION OPPORTUNITIES DURING VARYING TRANSPORTATION MODES 2.6.1 SUSPENDED DUMP BODY A common industry standard is the use of a flexible suspended dump body (SDB), such as Duratray, as pictured below. A study examining a Duratray System prototype concluded that flexible SDBs are suitable for mining and prototype rail applications (Ross, 2011). Ross looked at a coal mining application in South Africa and attempted to optimize the mine’s productivity. They were experiencing excessive carryback on certain haul trucks. The research was broken down into three categories: • Validity of design • Actual analysis and simulation • Statistical analysis A prototype Duratray SDB was installed on some of the mine’s haul trucks and the performance was analyzed. By using a sophisticated Analytic Hierarchy Model process, they were able to conclude in this case the adoption of the Duratray SDB was able to increase fleet performance and reductions in carryback. 13 Mining and Rail Car Duratray Suspended Dump Bodies and Prototype rail car 2006 Both Sources: Duratray North America Inc. These suspended dump body solutions are more capital intensive and require a rigorous cost benefit analysis before being implemented, slowing down expedited fleet conversion. Interim quicker-to-implement and less expensive options like an oil spray release agent may provide short term cost benefits, while a larger capital-intensive cost- benefit analysis is undertaken. It is important to note that these suspended dump body systems exist and are in use all over the world in increasingly smaller payload options, including on-highway truck applications. If SDBs were to be implemented fleet wide, thousands of units would be required as quickly as they could be manufactured, and scaling this process could include some delays. 14 2.7 MITIGATION OPPORTUNITIES AFTER TRANSPORT 2.7.1 CLEANING CONTACT SURFACES A common operational practice is cleaning the contact surfaces at the end of a shift or at a predetermined time or severity point. This is not ideal and leads to operational loses, potential damage to equipment, and various safety concerns. The practice is commonly called scratching and it can be done using various methods such as with excavators or large shovels. An example of scratching using an excavator is shown below. Scraping to eliminate carryback from corners - Mining Example 2.8 DO NOTHING OUTCOMES The Fox Lake Reclamation project is an example where nothing is done to mitigate carryback, and the outcome is severe. A contractor was working on a tailing’s reclamation project in a tailings pond and had few mitigation options available. The following characteristics were present: • Wet tailings water saturated. • Fine particle sizing 15 • 27°C during the day – colder overnight • Few options or ancillary equipment/facilities to support scratching or extended thawing of truck dump body. • Reliability degradations due to unbalanced loads cause wear on suspensions, and tires, and braking systems The phenomenon is far from ideal and leads to many undesirable potentials that involve safety, efficiency, and reliability degradations. Many small and/or remote operators in Canada’s North struggle with this problem with no real opportunity for mitigation options available. 2.9 INDUSTRY BEST PRACTICES Currently there are a variety of known Best Practices to combat carryback, with Operators determining which practices best suit their specific mitigation needs. The most commonly used intervention practices are: Mechanical intervention Installing flaps and moving mechanisms in the rock box allows for some carryback to Fox Lake Reclamation Project Pre- Trial March 26, 2023 - 30% est. Capacity Lost 16 be dislodged and discharged. Routing exhaust gases into rock box frames to melt and/or loosen the load has been used with mixed results. Heavy equipment can be used to try to remove the carryback; however, this method can be costly due to unintended damage to equipment, particularly from unskilled operators. Flexible beds Duratray-type rock and bulk rail boxes have been developed for mining and rail prototype applications. Design improvements by Duratray have been completed for on-highway trucks and sand & gravel applications worldwide. It is important to note the industry adoption and demand of smaller payloads with this type of solution. Over time there have been mining sites that have adopted smaller payloads - a very important evolution because 45 ton payloads are required for on- highway applications, creating safer highways, bigger payloads, and less fuel/energy consuming operations. This smaller payload brings in a broader opportunity to utilize this option for carriers. The same capital investment common in large mining applications still needs to be applied, along with calculations of cost benefit analysis. Suspended Dump Body rock box in use in Chile - Smaller capacity truck options exist and need to be considered in carryback reduction planning. 17 Operational Interventions Periodic inspections and/or automated detection systems can be planned and installed into the production process as necessary. The inspections can be incorporated into a truck’s maintenance cycle, or can be completed at the beginning or end of a shift. These inspections can vary depending on the equipment involved and the locations of transport transfer points. An automated detection system could be as simple as a truck scale, or as complex as discussed in the literature review Various Chemical Spray Release Barriers This research analysis studied the use of Biogard to eliminate carryback. It was proven to be an effective, environmentally friendly solution for industry. Some of these sprays are not environmentally friendly or recommended. Demurrage Demurrage refers to parking the transport vehicles in a heated area to let the bulk goods thaw out. This can be an effective low-cost option, however because of varying delays and compactions of materials, it is not always effective or possible to do. 18 Oil Sands Trials 2013 Biogard Release Agent - Komatsu 930 Haul Truck 3 PROJECT METHODOLOGY The methodology can be broken down into the following process steps: 1. Created a Project Team to Advise and Oversee the Research Key tasks for the team were stakeholder engagement, communication of objectives, safety, and the collaborative sharing of results. Team meetings were scheduled bi-weekly during the duration of planning and execution of the project. This included a closeout meeting where data and final report drafts were shared for inputs and consensus. 2. Determined Current State of Carryback for the 4 Sources (Ad hoc, Thompson, Flin Flon, Fox Lake) The Ad hoc example was estimated. The Thompson current state and Flin Flon/Snow Lake examples used historical data. Thompson historical data was measured to be up to ~25% and this occurred year-round. For Flin Flon/Snow Lake it was estimated to be ~20%. These estimates are based on haulage company’s actual experience and reporting. Note: Both of these mining concentrate examples had early interventions to reduce carryback to acceptable levels. Trucks used scale data at transfer points to accurately determine carryback for this research. The research project studied two of these methods and observed one other. 19 Application of Release Agent The application of a release agent – Biogard – was evaluated. Biogard is environmentally friendly which allowed for rapid trial approvals from supply chain partners. Obvious characteristics research partners would demand include: high water solubility 99%, high flash point, and no hazardous materials present. The use of such an agent brings with it several challenges depending on equipment size, location of application, and the intensity/duration of spraying. As can be seen in the picture below, manual application of a release agent can involve the need for additional heavy equipment and operational time commitments. An automated system may be required to ensure the benefits of the application outweigh its impact on operational efficiencies. In this area of application, emerging drone technologies and innovations could reduce the costs and safety risks of trials and limited operational requirements. To effectively spray where needed, when needed, a portable field spray unit was acquired and is pictured below. This unit was supplied by Biogard Inc. and has been refined over years of trial and corrections. Field Trial Spray Unit 20 The portable spray unit consisted of the following components: Spray wand and nozzle Electrical variable pump system - 100 - 300 psi 780-watt heating blanket (ideal heating temp 38°C) Heat-traced spray hose 45-gallon bulk Biogard portable unit holding tank with plumbed circulation Portable generator (not shown) Field trials were performed which included release agent spray testing, and measuring temperatures and flow rates to determine the impacts of the trials – including photos and scale data if needed or available. Prior to all field trials, necessary approvals were acquired through the collaborative exchange of information and team meetings. Obtaining the necessary approvals from industry partners and on-highway contractors is an important part of the process. This is a critical step, as the introduction of a potential contaminant – in this case, Biogard release agent – needs to be understood prior to use. Depending on downstream upgrading/refining processes the selection of any release agent needs operational due diligence understanding and safety protocols in place. Conclusions and recommendations for next steps were then added to promote the initiative and its associated benefits. The key to a broader understanding of carryback, and access to the mitigating range of options is the key benefit of this research. 21 PROJECT ANALYSIS AND FINDINGS The analysis is broken down by location. Where possible, a picture of the untreated equipment, a picture showing the results of the treatment, and the resulting research data are summarized. 20 22 4.1 SPRAY TRIALS The following spray trials (as shown in the images below) were performed at Moffatt Supply, whilst commissioning the portable spray system. The front-end loader bucket was cleaned and treated on April 23, 2023 with 0.5 gallons of Biogard at an overnight temperature of -11C. The result is an estimated increase of 5% of loader capacity resulting in improved efficiency and a reduction in greenhouse gas emissions. Cleaned and then Conditioned Loader Bucket Post Work Untreated Loader Bucket vs. Treated Post-Work with Biogard Release Agent 23 An untreated skid steer belonging to the Northern Regional Health Authority (January 2023) had an estimated loss in capacity of 15% due to carryback, as shown in this is a small example of an everyday occurrence of carryback that impacted sidewalk and parking lot snow removal efficiencies. It demonstrates that the carryback phenomenon is a common occurrence, even in small scale ‘every day’ practices. Skid Steer Loss of Capacity Untreated Typical Yard Work – Ad hoc random observation In summary, the three days of data for concentrate hauled from Thompson to Winnipeg are represented in the table below. Data for Flin Flon and Fox Lake are also included. 4.2 Poly Bags Poly bags lining the interior of rock boxes were used as the preferred on-highway transport mitigation strategy for the Vale concentrate studied in March 2023, in Thompson, Manitoba. This method was implemented approximately five years ago and eliminates carryback to near zero, however, it adds costs and a level of complexity for loading and unloading, which have been well managed by the transport provider over the years. Prior to this intervention poly bag method, Vale on-highway trucks were experiencing an average of 8-10 tons of carryback each trip. This was causing delays at unloading in Winnipeg and additional costs and time while the drivers manually shoveled out carryback each truck cycle. This intervention method is not always possible for Operators. Additional complexity for this transport cycle is the exothermic reaction of the specific ore body which further exacerbates if carryback growth is left untreated. 24 March 2023 Trial Carry back Current Methodology – Addition of Poly Bags The Thompson concentrate is planned to be transported to a refinery via rail cars in July 2023. There are risks associated with the future rail haulage and part of the research was to understand a potential mitigation strategy – the Biogard release agent – that could be utilized quickly if carryback gets excessive via this transport mode. The strategy is efficient as spraying rail cars can be set up and be available in a day if needed. Vale Inc. Concentrate Rail Car Feb. 18 2023 25 In summary, the three days of data for concentrate hauled from Thompson to Winnipeg are seen in the table below. In addition, the Flin Flon and Fox Lake data is also included. Trial Data Carryback April 2023 – Scales were used for Thompson data The Thompson trial data showed evidence of carryback forming along corners. Thompson Trial Carryback Evident in Corners of Boxes – April 13, 2023 26 4.3 Conveyor Belt Flaps On-highway trucks were modified to reduce carryback by installing used conveyor belting, this allows for a “flexing” of the rigid steel box surface. It is not ideal as it is a non “engineered” solution, like the poly bag example, which can add contamination and introduce process contamination risks. Observation of wear and necessary replacement is needed to ensure minimal downstream operational impacts. In many instances these solutions are installed without the entire knowledge and approvals from supply chain partners. Conveyor Belt Installed “Flaps” on Steel Surface The Snow Lake to Flin Flon concentrate on-highway trials were very successful, as seen to the right, and operators are eager to continue trials and implementation for the next seasonal cycle. Flin Flon Trial Results – Minimal Carryback 27 4.4 FOX LAKE RECLAMATION PROJECT The Fox Lake field trials consisted of two separate events: • Observation of carryback – tailings (wet, fine-ground materials) • Field trial of Biogard release agent – sand and gravel (glacial till) These trials occurred on different days and had different outcomes. The tailings trial and observation occurred on a much colder day than the sand and gravel trials. The results are listed below. Observation of Carryback – Tailings The tailings observations occurred on March 26, 2023, with the spray release agent trial scheduled for late in April 2023. When the trial took place, the temperature was -27C and the cargo was fine wet particle tailings. The observations shown demonstrate around a 30% capacity loss estimate. This is a common example of what operators deal with in remote locations. Fox Lake Reclamation Project Pre-Trial March 26, 2023 - 30% est. Capacity Lost 28 Biogard Release Agent Trial – Sand and Gravel The truck dump box was cleaned and Biogard was sprayed onto the rock box surfaces. Set-up to prepare the truck and application equipment takes about 10 minutes, and the actual spraying of the release agent usually takes only two or three minutes. Fox Lake Trial Sand and Gravel – Spraying Agent The trial of the Biogard release agent for the glacial till was successful; though no scales were available, visual observations indicated minimal carryback. Industry adoption of this method with the carrier was very successful and they intend to use it as an option moving forward. Fox Lake Post Dump – Minimal Carryback 29 5 CONCLUSION & RECOMMENDED NEXT STEPS The project team had several project stakeholders that have already adopted solutions to mitigate carryback in Northern Manitoba and intend to integrate solutions for their customers on an as-needed basis in the future. This includes on-highway transport and mining operations, though similar solutions could be expanded to the bulk rail sector. Spray release agents and an innovative mining or on-highway suspended dump body use are anticipated outcomes and innovations of this research paper. Similar benefits and range of solutions are available for bulk rail transport. 25 30 We Need More Data – Recommended Larger Study The research clearly establishes a progression of solutions that exist but are not widely known or used extensively in their target industries. The benefits of a larger study and broader data collection would further prove the benefits of these mitigation practices. Depending on the outcome of a larger study, the manufacture of an on-highway rock box Duratray prototype or Durarail bulk rail option may be deemed necessary or at the very least, desirable. There is a recommended progression of thinking, and it follows a fundamental project management approach: Determine the existing size of the problem/opportunity with data observations of current state. Propose mitigation methods and test them out progressively, with low-cost/low-risk options first – Cost Benefit Analysis with larger database. Recommend implementation of mitigation method(s) accordingly Share/communicate results and duplicate/scale up the cost-benefits: Do nothing. Scrape out manually Spray oil release agents Invest in a dump body. A Pan-Canadian or Multi-Modal Transportation Study is Recommended A study could focus on rail and intermodal routes, resulting in more focused findings based on a more data-centric analysis. The map on the next page highlights potential transport corridors and transportation transfer hubs in Canada that could be included in this research. 31 Potential Locations for Additional Research and Mitigation of Carryback More data concerning carryback is needed, and mitigation options identified in this research are not well known. Virtually all the data that exists lies with the mining operations. There does not appear to be any kind of industry-wide investigation underway to better understand the range of options available to address carryback inefficiencies. And aside from Biogard and Duratray, there are few (if any) larger companies actively pursuing technologies and equipment to mitigate carryback. Unfortunately, this is despite the known large-scale economic inefficiencies, and very real safety concerns exacerbated by the absence of industry-wide best practices. Future steps could include a larger-scale trial/study covering a broader range of test scenarios (season/temperature, material composition, moisture level); attempts to bring industry representatives together to collectively address carryback mitigation; and the development of standard operating procedures and safety protocols for these mitigation practices. As noted, the City of Thompson remains an ideal location for continuing these endeavors. It’s function as a northern hub for business and industry, local expertise, and ability to host long-term multi-level projects make Thompson a standout location. 32 REFERENCES CSIRO. (2021). Carryback and hang-up mitigation. Knights, P. (2023). Economic benefits of load volume scanning of underground mining trucks. https://www.tandfonline.com/doi/full/10.1080/19236026.2023.2186642?scroll=top&needAccess=true&role=ta b&aria-labelledby=full-article, All. Ross, S. G. (2011). Duratray Trial: Reducing the Effect Of Carryback at New VAAL Colliery. University of Pretoria. Retrieved from https://repository.up.ac.za/bitstream/handle/2263/17957/Ross_Duratray(2011).pdf;sequence=1 Yang, Q. (2022). Retrieved from Science Direct: https://www.sciencedirect.com/science/article/abs/pii/S0016236122006408