Porgera Gold Mine
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The Porgera Gold Mine is a large gold mining operation located in Enga province, Papua New Guinea.
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[edit] The Mine
The mine utilises both open pit and underground mining methods for ore extraction. Ore is processed in a mainly conventional plant, utilising several SAG and Ball mills, four Autoclaves, floatation cells and CIP / CIL. Gravity recovery is also used, Knelson concentrators doing the primary recovery, with an Acacia Reactor treating the concentrate.
A large fleet of Cat 777 and Cat 789 trucks haul on the surface, fed by O&K shovels, and smaller excavators and loaders. A motley collection of underground development and production drilling equipment break ground, which is bogged by Elphinstone RH series LHD's into a fleet of Elphinstone AD45 and Wagner MD20 trucks.
[edit] Security
The mine employs its own security force, numbering somewhere between 400 and 500 persons.
Some sections of the security force are licensed to utilise lethal force, however the rules of engagement are quite tight.[citation needed]
[edit] Location
The mine is located at the head of the Porgera Valley, in Enga, PNG. The site of the current open pit used to be Mt Wari Wari - it has now been excavated.
[edit] Ownership
The Porgera Gold Mine is operated by the Porgera Joint Venture (PJV). Barrick Gold - the worlds largest gold mining company, is the majority shareholder in the PJV and serves as the managing partner. Emperor Gold Mines is a minority shareholder.
[edit] Size
The mine is capable of producing in excess of one million troy ounces of gold per year and is widely regarded as one of the worlds top ten producing gold mines.
[edit] Impact
The mine has had a large impact on its immediate local area. While modern health care and education services have been bought to the valley by the mine, alcoholism, crime, rape and illegal mining have all increased.
[edit] Environmental Concerns
The mine practises riverine tailings disposal, by which processed ore from which the precious metal content has been removed is dumped directly into the local river. This results in an increased sediment loading of approximately 8 million tonnes per year. Additionally, the mine has two 'Erodible Dumps' - areas where soft waste rock are dumped and the high amount of local rainfall gradually washes into the local rivers. The increase in sediment loading is hard to quantify, but is generally thought to be in the range of 4 to 6 million tonnes per year.
The river systems eventually deliver hundreds of millions of tonnes of sediment into the Gulf of Papua. The main concern is the toxicity of the tailings, which contains significant quantities of cyanide, mercury and other heavy elements. The mercury is 'fixed' in a compound state by which it is thought it will not ultimately enter the food chain, however no conclusive research has been performed.
[edit] Workforce
The mine employs several thousand people, with over 80% of its work force from the direct local community mainly in unskilled and semi-skilled workforce. Management of the mine is almost exlusively composed of expatriates, mostly from Australia.
[edit] Pay
There is considerable variation in employee salaries. Wages for locally hired employee are low. An Papua New Guinean underground development drill operator at Porgera can receive an annual salary of approximately AUD$18, 000 per but an expatriate employee might receive a package of further benefits to an annual value of more than $90,0000. Management packages can be AUD$140, 000 per annum, and include health cover and other benefits.
This disparity in remuneration is often explained by the employers in terms of being tailored to needs of the local market.
