Tailings are a common by-product remaining following the extraction and recovery of valuable minerals from mine operations. They are generated by the milling process and are a mixture of finely ground sand- to clay-sized rock particles, water and processing reagents.
Tailings management is an important component in the design and operation of mining projects. The objective of tailings management is to ensure robust processes are in place to ensure safe, long-term storage of mine tailings. New Gold has implemented a comprehensive tailings management approach focused on identifying and minimizing potential environmental and social impacts of our tailings facilities, from construction through to post-closure.
New Gold’s Tailings Facilities
Two of New Gold’s operations, the New Afton mine and the Rainy River mine, involve active tailings facilities. In addition, there is an inactive tailings facility located at the New Afton mine. More information about these tailings facilities can be found in the table below. None of the company’s active or inactive tailings facilities uses upstream construction.
Tailings Management at New Gold
As a member of the Mining Association of Canada (MAC), New Gold is committed to implementing the Towards Sustainable Mining (TSM) performance system at each of its sites in Canada (which includes both sites with tailings facilities). This includes the TSM Tailings Management Protocol, which sets out best practices in the area.
New Gold’s tailings management practices include the following important features:
- Design: The design of New Gold’s tailings facilities takes into account the climatic and ground conditions at each site. For example, our tailings facilities are designed to consider significant natural events, such as the probable maximum flood, so that the tailings can be safely contained in the event of extreme weather or seismic events.
- Operations practices: Each site has an operations, surveillance and maintenance manual (OMS Manual) which sets out, among other things, how the site’s tailings facilities will be operated and maintained in order to ensure that they function in accordance with their respective design performance objectives, as well as regulatory and corporate policy obligations.
- Risk assessments: Each site conducts regular risk reviews that include tailings-related risks, the key results of which are reported to corporate management at least annually.
- Engineer of record: Each site has appointed a qualified external professional engineer and their firm to be the engineer of record for its tailings facilities.
- Surveillance technology: Sites use surveillance systems, such as piezometers, inclinometers, remote sensing and other technologies to monitor tailings dams and water levels. The OMS Manual sets out early-warning trigger and alert levels, facilitating early identification and management of potential dam stability concerns.
- Inspections by personnel: The company’s tailings facilities are regularly inspected by trained New Gold employees – sometimes as frequently as several times a day.
- Dam safety inspections: Formal dam safety inspections are conducted at least annually by the engineer of record. Recommendations made by the engineer of record are tracked to ensure follow-through by site personnel.
- Dam safety reviews: Each facility is subject to detailed third-party external dam safety reviews every five years, comprising a review of the design basis, construction and performance.
- Independent reviews: The company has an independent technical review board (ITRB) to provide independent, expert advice regarding the technical aspects of our tailings facilities. The ITRB meets at least twice per year to review information about tailings management practices at each facility.
- Emergency preparedness: Each site has a detailed emergency response plan, which is regularly reviewed and updated.
|New Afton||Rainy River|
|New Afton tailings storage facility||Pothook tailings storage facility||Historic Afton tailings storage facility||Rainy River tailings management area|
|Status||Active||Active||Care and maintenance||
|Current maximum height||37 m||10 m||70 m||12 m|
|Current storage impoundment volume||21,300,000 m3||2,650,000 m3||33,000,000 m3||7,780,000 m3|
|Most recent dam safety inspection by engineer of record||2018||2018||2018||2019|
|Most recent dam safety review||2017||2018||2018||New facility; first review expected 2022|
|Most recent ITRB review||2019||2019||2019||2019|