Emissions and Waste Management

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Approach

Mining activities – extracting, processing and refining – generate air emissions and both mineral and non-mineral waste. These wastes and emissions, as well as the process for storing and transporting these wastes, can pose serious, sometimes catastrophic, environmental and public health risks. Effectively managing wastes and emissions and ensuring their safe storage and transportation is critical to protecting people and the environment; reducing the liabilities and long-term risks associated with inadequate management facilities and protections; and addressing the salient human rights issues – the right to life and healthy and safe working conditions – associated with our business activities.

Our Sustainability and Stakeholder Engagement Policy and a set of global standards outline our commitment and set minimum requirements to manage waste and emissions generated by our business activities in a manner that protects the environment and human health; promotes beneficial post-mining land use; and reduces post-mining closure and reclamation liabilities. Our approach to managing emissions characterized as greenhouse gases (GHG) is detailed in the Energy and Climate Change section of this report.

Our Waste Management Standard requires sites to address the generation, segregation, collection, storage, transportation, minimization, reuse/recycling and disposal of hazardous wastes, non-hazardous wastes, wastewater and mercury.

Newmont does not use mercury to mine or extract gold. However, mercury naturally occurs in ore at several of our operations, and ore processing can generate mercury compounds and gaseous elemental mercury. Newmont captures gaseous mercury using maximum achievable control technology (MACT) – as defined by the Nevada Mercury Control Program standard.

We are committed to permanently removing mercury byproduct from circulation using long-term safe storage solutions. In the U.S., we are precluded from exporting mercury, and the U.S. Department of Energy (DOE) oversees the long-term storage of elemental mercury. Until the DOE constructs a permanent facility and begins accepting mercury, we are safely storing mercury on site.

Our Waste Rock and Ore Stockpile Management Standard requires sites to characterize ore and waste rock and to carefully design, construct, operate, close and reclaim rock stockpiles including pit backfills.

This standard also addresses the risk to surface and groundwater quality from acid rock drainage (ARD), which is generated when water comes into contact with certain minerals in the rock that are oxidized by exposure to air, precipitation and naturally occurring bacteria. Site-specific management strategies aim to ensure that waste storage facilities are designed and operated in a manner that minimizes ARD risks. In instances where prevention is not possible, we collect and treat ARD in a manner that protects human health and the environment.

Newmont is an active member of the International Network for Acid Prevention (INAP), an industry-led group that promotes best practices in handling potentially acid-generating materials such as waste rock and tailings.

Our Tailings and Heap Leach Facility Management Standard requires sites to protect surface water and groundwater, prevent uncontrolled releases of pollutants or contaminants to the environment, manage process fluids and meet requirements for closure and reclamation.

Tailings are created as mined ore is reduced into sand-sized particles and then mixed with water and moved as slurry through the extraction process. After removal of the valuable minerals, the remaining milled rock slurry – called tailings – flows to an engineered tailings storage facility (TSF). TSFs are designed to safely contain tailings even during extreme weather or seismic events. In addition to daily inspections conducted by on-site staff, qualified geotechnical engineers inspect every TSF at least once a year. These inspections include visually examining its physical condition and reviewing all monitoring data, tailings management practices and process information. For any issues identified, a meeting is held immediately after the inspection to develop and implement a remediation plan. Follow-up inspections are then conducted to verify that the issues have been remedied. Details about how we manage tailings are available in a fact sheet on our website.

Our Hazardous Materials Management Standard requires sites to minimize the use of hazardous materials – inclusive of hydrocarbons and cyanide – and transfer, distribute and store such materials in a manner that protects human health and the environment. We seek to minimize the quantity of hazardous waste we generate by replacing hazardous chemicals with less hazardous products whenever possible.

Our sites minimize the volume of hydrocarbon wastes requiring hazardous disposal by recycling almost all waste oils and greases, either through third-party vendors or on-site processes. On-site recycling includes using waste oil for fuel in combustion processes or recycling into an explosives component.

Our activities also generate non-hazardous waste such as scrap metal and spent tires. Every effort is made to recycle or reuse hazardous and non-hazardous wastes. All materials are recycled or disposed of in accordance with applicable laws and regulations.

Our material air emissions are sulfur and nitrogen oxides (SOx and NOx), particulate matter (PM) and mercury. SOx emissions are primarily generated at coal-fired power plants such as our TS Power Plant in Nevada and during thermal processes that heat pyritic ore such as at our Twin Creek autoclaves. NOx emissions are produced during combustion of diesel fuel, coal, natural gas and propane in stationary sources such as furnaces and power plants. Our fugitive PM emissions (i.e., irregular emissions from dispersed sources) are primarily dust from mining activities such as blasting, excavating and crushing ore.

In Nevada, our TS Power Plant is a 242-megawatt coal-fired electricity generating plant that uses a brominated activated carbon injection system and a continuous emissions monitoring system (CEMS), one of the first mercury-specific CEMS in the United States, to significantly reduce mercury emissions. The power plant also controls SOx, NOx and PM emissions and is compliant with MACT standards on emission limits.

We annually report our air emissions through the U.S. Environmental Protection Agency’s (EPA) Toxic Release Inventory (TRI) program and Australia’s National Pollutant Inventory.

2016 Performance

Newmont generated 336 million tonnes of waste rock and 97 million tonnes of tailings in 2016 – a decrease of 1.2 percent and 28.8 percent, respectively, compared to an overall increase in annual consolidated gold production from continuing operations of 4.2 percent. Much of the year-over-year decrease was due to the divestiture of our Batu Hijau operation, offset in part by the addition of the Cripple Creek & Victor operation.

We generated approximately 34,831 tonnes of non-hazardous waste and 12,000 tonnes of hazardous waste at our operations in 2016. Our global output of both non-mineral hazardous and non-hazardous waste can vary due to activities such as maintenance requirements (volume of oils and lubricants), construction activities (quantity of packaging materials and scrap) and storage (space for metals recycling).

In 2016, we recycled 4,549 tonnes of hazardous waste and 21,234 tonnes of non-hazardous waste, including 4,733 tonnes of used oil.

Our global elemental mercury production increased in 2016 to 19 tonnes, reflecting the variable mercury content in our ore and our efforts to remove mercury from our air emissions.

Our air emissions reflect the inherent variations in ore composition as we mine from one part of the ore body to another.

Compared to 2015, total mercury emissions decreased 83.3 percent, and our total SOx emissions decreased 99.7 percent. The decline reflects the first full year since the decommissioning in mid-2015 of the Gidji roaster at KCGM – which previously accounted for around 99 and 95 percent of Newmont’s total annual sulfur dioxide and mercury emissions, respectively. The data also reflect the divestiture of the Batu Hijau mine in Indonesia and the addition of the Cripple Creek & Victor operation in the United States.

Efforts in 2016 to better manage our waste and emissions include:

  • As a member of the International Council on Mining and Metals (ICMM), we participated in a global tailings storage facilities (TSF) review, which the ICMM initiated following the devastating tailings dam failures in Canada in 2014 and in Brazil in 2015. A report on the review was published in 2016 and led to all ICMM members endorsing a new Tailings Governance Framework to minimize the risk of future tailings dam failures.
  • In the U.S., an amended Toxic Substance Control Act that was signed into law allows mining companies to store mercury at mine sites while the U.S. Department of Energy finalizes a site and constructs a permanent mercury storage facility. As a result, our Nevada operations began storing elemental mercury on site rather than shipping to a Resource Conservation and Recovery Act (RCRA) licensed facility in Alabama.
  • Our internal task force continued to evaluate options for the safe transport and retirement of all our non-U.S.-produced byproduct mercury. During the year, the task force visited a facility in Europe that transforms elemental mercury into mercury sulfide – a stable, naturally occurring mercury mineral compound that is typically retired in deep, underground salt mines.
  • At the end of 2015, the U.S. Environmental Protection Agency’s (EPA) new ozone standard, which lowers the amount of allowable ground-level ozone from 75 parts per million (ppm) to 70 ppm, went into effect. In 2016, we confirmed that none of our U.S.-based operations are in known non-attainment areas – those areas where ozone readings are consistently above the EPA’s air quality standards.
  • Through our continuous business improvement program called Full Potential, we identified waste reduction and recycling opportunities such as increasing the tire life on haul trucks, employing an expert system that optimizes the use of reagents and other consumables, and identifying assets (e.g., HDPE pipes and valves) that could be recycled rather than disposed.
  • We completed construction and began testing of a paste backfill plant in Nevada that transforms tailings waste into a paste-like material that is used as backfill to stabilize previously mined areas in the Leeville underground mine.
  • In late 2015, the Yanacocha operation in Peru installed non-hazardous waste compactors at the La Quinua waste management facility, which ships waste to Lima 600 miles away. In 2016, which was the first full year of using the waste compactors, the facility saved approximately $320,000 in shipping costs and fuel savings as a result of the reduced shipping volumes.
Total waste rock and tailings (in million tonnes)
Total waste rock generated
Total tailings
2012 2013 2014 2015 2016
Total tailings 145.4 173.0 146.1 135.9 96.8
Total waste rock generated 559.6 568.7 406.6 340.1 335.9
(in million tonnes) 2012 2013 2014 2015 2016
Total waste rock generated 559.6 568.7 406.6 340.1 335.9
Total tailings 145.4 173.0 146.1 135.9 96.8
Total 705.0 741.7 552.7 476.0 432.7
Annual mercury production (in tonnes)
(in tonnes) 2012 2013 2014 2015 2016
Elemental mercury (Hg) 39.3 24.8 20.9 12.5 19.0
Air emissions – gas (in thousand tonnes)
SOx (SO2)
NOx (NO2)
PM10
Carbon monoxide (CO)
2012 2013 2014 2015 2016
Carbon monoxide (CO) 2.4 2.5 2.3 2.6 3.4
PM10 21.0 22.3 19.0 19.8 17.3
NOx (NO2) 6.0 6.9 6.4 7.1 5.5
SOx (SO2) 173.8 171.6 168.2 34.0 0.1
(in thousand tonnes) 2012 2013 2014 2015 2016
SOx (SO2) 173.8 171.6 168.2 34.0 0.1
NOx (NO2) 6.0 6.9 6.4 7.1 5.5
PM10 21.0 22.3 19.0 19.8 17.3
Carbon monoxide (CO) 2.4 2.5 2.3 2.6 3.4
Total 203.2 203.3 195.9 63.5 26.3
Click here for full data tables

Future Focus

In 2017, we will conduct a comprehensive review of our materials management approach. Among the activities planned to support this broader effort:

  • Updating our Tailings and Heap Leach Facility Management Standard to incorporate the Tailings Governance Framework outlined in the International Council on Mining and Metals (ICMM) position statement related to minimizing the risk of catastrophic tailings dam failures; and
  • Conducting workshops with regions and sites to think about broader sustainability objectives and ensure compliance with the new ICMM guidance on tailings disposal.