A guide to leading practice sustainable development in mining

Box 1: Major recent incidents involving cyanide
1. In May 1998 loss of 1800 kilograms of sodium cyanide to
the Barskaun River, Kyrgyzstan, followed a truck accident
en route to the Kumtor mine (Hynes et al. 1999).
2. In 1995 thousands of migratory and non-migratory waterbirds were
killed at the tailings dam of the Northparkes mine, NSW, Australia, due
to a poor understanding of the significance of cyanide chemistry and
inappropriate analytical procedures (Environment Australia 2003).
3. In 2000 the tailings impoundment at Baia Mare, Romania, was
breached, releasing a cyanide plume which travelled for 2000
kilometres downstream, killing very large numbers of fish in the
Tisza and Danube rivers, and disrupting the water supply (UNEP/
OCHA 2000) (Environment Australia 2003). Excessive treatment of
cyanide with hypochlorite and chlorine exacerbated the problem.
4. A pallet of dry cyanide product, which fell from a helicopter
en route to the Tolukuma gold mine in Papua New Guinea in
2000, was successfully cleaned up (Noller & Saulep 2004).
5. Cyanide solution from an incompletely discharged ISOtainer
was allegedly released on the roadside after a delivery
truck left a mine in the Northern Territory in 2002.
6. Due to confusion over the number of valves in the cyanide
plant at the San Andres mine, Honduras, 1200 litres of cyanide
solution was discharged into the Lara River in January 2002.
7. Water contaminated with cyanide entered the Asuman River from the
Tarkwa gold mine in the Wassa West District of Ghana in October 2001,
killing fish and disrupting local water supplies. Another discharge into the
river from a ventilation shaft in January 2003 rekindled community health
and safety concerns, although this water was later shown to be potable.
8. In February 2007, a road train carrying three 20-tonne containers of
solid sodium cyanide in the Northern Territory tipped over, spilling
pellets onto the side of the road and into a non-flowing watercourse.
Most spilled product was collected, and contaminated water and
soil were cleaned up and disposed of at a nearby mine site.
A number of gold mines use cyanide destruction techniques in order to reduce the
risk of environmental impact in tailings deposition. The Granites lease is about 550
kilometres north-west of Alice Springs and is owned and operated by Newmont
Tanami Operations (NTO). It has been operating since the mid 1980s. The mine
initially placed tailings in conventional paddock tailings storage facilities (TSF) and
later expanded this practice to inpit tailings disposal. In-pit tailings disposal has the
advantage of storing tailings in a safe repository; filling a void that would otherwise
remain open; and reduce the potential for wildlife mortalities especially birds.
102 LEADING PRACTICE SUSTAINABLE DEVELOPMENT PROGRAM FOR THE MINING INDUSTRY