Aaron Nieveras

Key Achievements and Functions:

- Developed tools and systems to support robust carbon accounting, including data collection, calculation methodologies and emissions inventory management particularly in:

• Scope 1 - Site level emissions forecasting and analysis (e.g Pilbara and Simandou, US Borates)
• Scope 2 - Calculation of Residual Mix Factor (RMF) for Australia and New Zealand
• Scope 3 Value Chain Emissions - end to end emissions calculations and verification for Transport (Marine and Logistics), Purchased and Capital Goods, Fuels and Energy Activities, Employee Commute and Business Travel

- Conduct accurate and timely measurement, analysis and reporting of Rio Tinto's carbon emissions to support ongoing compliance with relevant regulations and reporting frameworks (e.g. National Greenhouse and Energy Reporting Scheme, Emissions Reduction Fund and Safeguard Mechanism)

- Stay up to date with evolving carbon accounting standards, methodologies and regulatory requirements

- Analysis of several Life Cycle Assessments (LCAs) in relation to emission factors of purchased goods and Rio Tinto's products

Technical Excellence Business Partner (Analytics CoE)

• Capability working group lead responsible for planning and partnering for the successful delivery of multiple transformative initiatives to grow analytics capability.
  o Analytics community and technology stack (expert onboarding program)
  o Production of the awareness level data and technology e-learning module
  o Design of five (5) foundational modules to support growing interest in advanced analytics.
• Championed analytics community events like the Machine Learning 101 Webinar Series with over 2000 people in virtual attendance.
• Developed and published multiple intranet sites using O365 to support the analytics community at Rio Tinto.

Technology and Digital Infrastructure Lead for the Technical Excellence team

• Internal recognition on the excellent design, content building and publication of over 150 intranet sites (Sharepoint and Sharepoint Online) serving over 25,000 Rio Tinto users within mining, geology, asset management, processing, automation and advanace analytics communities.
• Data storytelling through PowerBI to support the skills check initiative
  o Process automation for key capability projects like RioExcel using MS Flow and Sharepoint
  o Provision of high level statistics and metrics spanning from sentiment analysis to value analysis.

• Co-designed, built and sustained a global websites and applications to supporting knowledge transfer and retention centred around the processing technical discipline.Some example as follows
  o Rio Tinto's global Processing Asset Register (PowerBI)
  o Processing Site Information Centre

Key Achievements and Functions:

• Led teams of analytics professionals over the delivery of machine learning projects in RT Kennecott Copper
• Established team-working dynamics and driven several stakeholder engagements to progress scoping and data assessment for RTKC Stockpile Project
• Met all required deliverables to transition the Flotation (Recovery) project from proof of concept (POC) to minimum viable product (MVP) stage.
• Technical translator, applying technical domain and business knowledge to facilitate effective information sharing between project board / management, clients and analytics team
  o Assures progress is achieved through management of scrum related events and documents / artifacts.
• Timely identification and escalation of risks and execution of control / mitigation strategies

Key Achievements and Functions:

• 2015-2017 cost reduction (~500K AUD) in crushing circuit related expenses through implementation and management of performance-based liner change outs.
• Increased primary crusher fines product recovery through screen mat design changes which contributed in achieving record-setting throughput in 2016 (107% against plan).
• Size vs Recovery test resulting in mill power cost reduction of ~25k AUD per month
• Condition based change program for hydrocyclones leading to longer operational life (1500 to 3000 hours)
• Formed and supervise a team of 4 (including external suppliers) to conduct grinding media evaluation through wear modelling as well as Mark Ball Testing. Actual savings of ~600K AUD per year.
• Ball Mill technical evaluation, simulation and modelling with changes implemented in trommel designs.
• Occasionally assumed Technical Superintendent role managing 2 Senior Metallurgist and 1 Met Technician.
• Provide specialist advice in areas of crushing, grinding, leaching, CCDs and Solvent Extraction Circuit.
  

Key Achievements and Functions

• Supervision of 4 Metallurgical Aides and 2 Metallurgical Technicians.
• Highly involved in building and implementing the feed size control and mill feed fuzzy logic (SAG Mill) which successfully improve Mill throughput
• Implemented logic controller on ball charging to reduce steel consumption
• Conducts regular mine to mill meetings for better control of incoming feed
• Metallurgical Accounting – Daily Production data, Elution and Gold room balances, End of month collation and resets.
  o Mentor, train and assists Graduate Metallurgists assigned in grinding and flotation
• Inspect mills (SAG, Ball, ISA / Ultra Fine Mill) on shutdown. Evaluates and review mill lining wears and provides technical advice on liner design adjustments.
• Cyclone and Concentrator Bowl checks ensuring maximum wear has achieved minimizing cost of change outs
• Flotation Circuit assessment and optimization including adjustment of reagent, slurry density, froth depth, airflow rates etc.

Key Achievements and Functions

• Minimizing gold dissolution in flotation circuits through optimize use of Sodium Cyanide
• Head assay verification tests and multiple reagents testing including alternative depressants to Sodium Cyanide
  o Copper and zinc flotation monitoring and optimization to ensure acceptable grade and recovery through pH, sizing, specific gravity readings, reagent control, etc.
• Decipher and analyzes disparities in metal grade or recovery. Investigating the cause whether operational, metallurgical or maintenance related.
• Do metallurgical balance and accounting of marketable products (Cu, Zn, Au and Ag) and consumables to established efficient operational parameters