The mines that make up Barrick Gold’s Hemlo property in northwestern Ontario have been in operation for 26 years and still have a bright future. Production is currently expected to continue until 2018, and Hemlo is setting the pace for other mining companies across Canada with its operations-wide best practices in sustainable mining performance.
Barrick has held full ownership of Hemlo since 2009, when it bought Teck Resources’ equal share for US$65 million. The two mines that comprise the operation – David Bell, an underground mine, and Williams, an underground and open pit mine – have been in operation since 1985. Together, they produced 227,000 ounces of gold in 2011.
Honoured previously for its water conservation and tailings management strategies, the operation earned the Mining Association of Canada’s Towards Sustainable Mining (TSM) Leadership Award after achieving “A,” or “good,” rankings in all of the 2010 TSM performance categories: external outreach; crisis management planning; tailings management; and energy use and greenhouse gas emissions. CIM Magazine connected with members of the Hemlo team to learn how Barrick’s only Canadian operation has taken the lead.
Cyanide and the environment
The Hemlo property near Marathon, Ontario has
586 Barricks employees and another 200 contractors.
© Barrick Gold
Barrick is a signatory to the International Cyanide Management Code (ICMC)
. Its operating procedures and emergency response protocols reflect ICMC standards, and the company’s cyanide management practices, including Hemlo’s, have been audited by a third party to certify compliance with the code. The tailings management facility at Hemlo runs with proprietary software, and includes infrared monitoring backed up by video cameras that run continuously. Pressure sensors along the tailings pipeline also register potential problems. For instance, a leak might be detected through the infrared cameras located along the tailings corridor, or by a change in pressure differential. As well, the entire tailings management facility is visually inspected at regularly scheduled intervals throughout the 24-hour workday.
“An automated alarm system is in place and mill personnel are notified in case of a pressure differential in the line,” says Shane Hayes, closure coordinator at Hemlo. “Procedures are in place to investigate the pressure differential alarms immediately.”