Following the lode

The application of scientific method, good policy and sound judgement has producing advances in mining methods and techniques in Australia for a century and a half. Michael Sheffield writes for Australian Mining.

Broken Hill’s mining history is a classic ‘rite of passage’ story, as relevant to the growth and development of Australia’s industrial and finance sectors is it is to the mining industry.

The century-and-a-quarter from the formation of Charles Rasp’s and George McCulloch’s ‘syndicate of seven’ in 1883 has it all: the getting of wisdom, fortunes earned from sound judgement and heroic endeavour, and reminders that even the most brilliant pasts must end, with new directions taken and new solutions found.

“Don’t ignore history,” geologist Ian Plimer said.

And for those who know how rich the quartz of history can be, the need for the decisions which shape today’s mining sector to be informed by the vision and clear thinking seen often in the choices that shaped Broken Hill provides an imperative that reconnects us to that turbulent century.

“We ignore the advances and the mistakes of the past at our peril,” Plimer said.

Points of connection, as they relate to developments in mining methods and techniques, can be seen in;

· the BHP Board’s wisdom in buying in international expertise to manage an operation whose vast scale called for competencies which Australia at that time simply did not possess

· Its enlightened pursuit of safe mining practices

· the tenacity that characterised Broken Hill’s development of the flotation process

· the speed with which boom could turn to bust in the laissez faire world of 19th and early 20th Century capitalism and the extraordinary demands that placed on company directors

· the scale of future earnings that can be foregone through ‘point-and-shoot’ decision making

· the extent to which growth in the mining sector is affected by commodity price changes triggered by world events and policy shifts

· Broken Hill’s continuing contribution to industry development.

Cameos on these themes

In December 1886, the Broken Hill Proprietary Company Limited’s Board accepted director Sam Wilson’s judgement that international expertise was needed to manage the gigantic lode for which they had assumed responsibility.

Wilson, a mining engineer with experience in smaller mines, had seen the U.S.A.’s giant Comstock lode, with its ventilation problems, high temperatures, underground fires and shifting ground as the appropriate proving ground. It was to Nevada that the Board sent him and from there that he recruited engineer and metallurgist William H Patton and metallurgist Hermann Schlapp.

Patton introduced square-set mining to Broken Hill, remediating the situation that had so gravely concerned Wilson.

Broken Hill’s wide lode pushed the Comstock method of securing stopes with heavy-set Oregon timbering to the limits of its functionality, however, and despite local variations on the theme massive ground subsidence in July 1905 destroyed most of the mine between the -400 foot and -600 foot levels and led to the abandonment of the mine buildings and most of the mill.

At the beginning of the last century, development of the frothing process pushed metallurgists beyond the limits of scientific reason and human tolerance in a decade-long race pursued by separate teams of researchers in separate mine laboratories, and working under levels of pressure that reflected the commercial significance of their goal and the need to avoid triggering patent litigation that was an ongoing collateral cost of their work.

The resultant process is a cornerstone of metallurgy, its significance on a par with the Bessemer and cyanide processes.

Selective flotation, made possible by Broken Hill’s metallurgists, allowed American giant Anaconda to increase its recovery of coper from 79 per cent to 95 per cent. That gain came bouncing back in job losses as Anaconda grabbed market share and the price of copper fell.

In 1887, as the price of its £19 shares passed £174 the directors spun off more than half the company’s leases to three newly formed entities. Their decision to ‘court the rich sisters in the middle part of the lode and spurn the cinderellas at the distant ends’ as Geoffrey Blainey put it, had its opportunity cost.

“In their own lifetime they would have become wealthier if they followed the lode to the north and south instead of moving into steel,” he said.

As bringers and deniers of development opportunities, however, government policy shifts take a lot of beating. In 1938, the Lyons Government put a blanket ban on the export of Australian iron ore to block Nippon Mining’s proposed development of Yampi Sound as a source of iron ore for Japan’s steel mills. When the flood gates opened in 1960, Lang Hancock, who had been waiting for the starter’s gun for seven years, headed straight for Rio Tinto with his partner, E A Wright. The rest, as they say, is history.

Growth and Diversification

As Broken Hill acquired advanced mining methods and skilled mine workers from the Comstock, so too it became a disseminator of capital and expertise.

In 1892, BHP diversified into steel. In 1914, as Broken Hill Associated Smelters, North Broken Hill, South Broken Hill and Zinc Corporation established the world’s largest lead and tin smelters at Port Pirie in South Australia. In 1916, they established, in Tasmania, what would become the world’s third largest zinc works.

In the inter-war years, the ‘Collins House’ alliance acquired the Port Kembla copper refineries and smelters, made brass and copper sheet, rod and cable, participated in the development of the Commonwealth Aircraft Corporation and the establishment of a pulp and paper mill at Burnie, and extended into light and heavy engineering, fertiliser manufacture, gold mining, oil search and timber milling.

Zinc Corporation merged with Imperial Smelting Corporation in 1949 to become Consolidated Zinc and, in 1962, joined with Rio Tinto to form Conzinc Riotinto.

From the 1960s, CRA pioneered iron ore mining in the Pilbara and Bauxite mining at Weipa, it opened the world’s biggest diamond mine, it began copper mining on Bougainville, and it mined Coal in Indonesia.

In 1989, BHP, CRA and North Broken Hill Peko brought their activities together as Pasminco — their deep underground mines at Broken Hill, their other lead mines in Tasmania and at Cobar, their smelters and refineries at Risden, and their smelters at Port Pirie and off-shore.

Future Directions

Contemporary work practices are being shaped by global market imperatives (and local supply factors), by major shifts that are taking place in community expectations regarding workplace safety and environmental impacts, and by the ongoing development of new ICT capabilities.

In a research paper from 2003 titled ‘Practical and Strategic Technology Choices for Advanced Mining’, CSIRO research scientist, Jock Cunningham, and research engineer, Ian Gipps, concluded that “The underlying need to improve safety, productivity and profitability while reducing environmental impact, combined with the need to improve the conversion or resources to reserves continues.

“The changing requirements of society as reflected in legislation has changed the approach of the industry towards risk assessment/minimisation and duty of care in addition to operating limits where they are relevant. The responsibility for the safety of technology is spread across its life cycle from research and development to obsolescence.

“These changes will increase the demand for services that can assess technology against appropriate standards and provide independent audit and certification. While fatalities and injuries have been falling consistently and have responded to focussed procedural control, further reductions are likely to flow from the introduction of new technology involving automated and remote operation.”

Anticipating increasing acceptance of advanced mining technologies they noted that “Teleoperation of LHDs has reached the stage of general acceptance and automated vehicle technology may now have begun its migration to typical mine applications brought about by a combination of management philosophy, innovative guidance and control methods and improved communication technology.”

Observing that “the trend towards interconnectivity for technology that will make the centralisation of its control more feasible and perhaps desirable,” and that “advances in several technologies applied to existing unit processes have reached a stage where new mining methods can be seriously contemplated for practical application in a five to ten year time frame,” they anticipated that “these new methods will be designed to almost remove people from the ‘active face’ and will significantly improve safety, profitability and sustainability of the resource.”

The attention that they draw to:

· the need for equipment developers to make provision for their technologies to be used in an integrated way with competitors’ equipment

· the need to target hazard elimination or reduction through improvements to equipment design, the introduction of engineering controls and the isolation of people from areas where machines and materials interact

· teleoperation as an alternative to line-of-sight operation of Load Haul Dump vehicles to help eliminate fatalities and increase productivity, and

· the introduction of new non-entry mining methods that are delivered and optimised for machinery in the absence of people in close proximity,

· neatly summarise the main themes that will shape the development of methods and technologies in underground mining in the immediate and longer term future.

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