It would have been better to call for emergency help once it was clear the situation was unprecedented. Emergency services could have been stood down if necessary. The delay probably made no difference to the survival of the men, but the mine manager was not to know this. Within the hour local police officers reached the mine and officers at Police National Headquarters in Wellington decided that the police would lead the emergency response. The next day further New Zealand and Australian mines rescue and mining experts arrived at the mine, their travel needs facilitated by the police, who expertly managed many logistical demands throughout the response effort.
Conducting the emergency response was very complex, given the need to co-ordinate multiple agencies, make crucial decisions and maintain external communications, including with the families, when time was of the essence. After an underground fire or explosion coal miners worldwide are trained to self-rescue by walking or driving out of the mine. It is standard practice for miners to carry a self-rescuer, a form of breathing device for use in a toxic atmosphere.
The workers at Pike River carried minute duration self-rescuers and were trained to use the drift as the preferred escapeway in an emergency. As at November it was the only useable means of egress. Climbing up the m ventilation shaft — the designated second egress — would not have been possible wearing a self-rescuer and with the shaft effectively functioning as a chimney after the explosion.
The MRS operates through a charitable trust to provide training and emergency response services to the mining industry. It is funded from a coal levy and payments received for its ancillary services. Mines rescue crews were deployed to Pike River immediately after the pm callout. Throughout the rescue phase local crews made up of volunteer miners, assisted by their Australian counterparts, were on standby, but to their frustration conditions did not permit entry into the mine. The MRS also played a major role in sealing and using the Queensland MRS inertisation device to stabilise the mine following the sequence of explosions, and successfully led an operation to reclaim and reventilate the first section of the drift in During the emergency response reference was made to a place in the mine where the men could be waiting in fresh air to be rescued.
The methane drainage pipeline passed through the stub, which also contained a supply of spare self-rescuers, and first aid and fire-fighting equipment. There was a roll-down brattice curtain at the entrance, but it did not provide an effective seal. Nor was there any assurance that, following an explosion, fresh air would flow down the slimline shaft. The stub was an FAB in name only, not a place of safety in an emergency.
What's Mine's Mine — Volume 1
Nor was it suitable as a changeover station for anyone wanting to don a fresh self-rescuer. The emergency response was hampered by a lack of information. The number of men missing underground remained uncertain until Saturday morning, 20 November, when the correct figure and the breakdown between employees and contractors was announced. There could be no rescue attempt without information on the mine atmosphere.
Reporting from underground stopped at the time of the explosion and Pike had no back-up system. For the first five days the only samples available for analysis were taken from near the top of the ventilation and slimline shafts, but they were not considered representative of conditions underground.
A new borehole drilled into the heart of the mine reached pit bottom on the morning of 24 November. The availability of representative samples stimulated hope, but the second explosion that afternoon put paid to any thought of a rescue attempt. There is no predictable period during which a gassy coal mine may be safely entered before a second explosion may occur. Secondary explosions are unpredictable, and the window of opportunity fallacy has claimed many lives in mines throughout the mining world. International best practice is to re-enter an underground coal mine only on the basis of representative and reliable atmospheric information.
This did not exist at Pike River. Entry into the mine would also have been unusually challenging with no ventilation or second egress, and a 2. CIMS is generic, not specific to mining. That plan must be approved by an incident controller. The controller and the management team are based close to the incident site, where decisions are made promptly and with the benefit of expert advice. After the police assumed the lead agency role at Pike River the three management and the incident controller roles were assigned to police officers, meaning the leadership group at the mine lacked mining expertise.
Superintendent Gary Knowles, the incident controller, based himself at Greymouth, but was required to refer many decisions to an assistant commissioner at Police National Headquarters in Wellington. This three-level structure was cumbersome and unsuited to the rapidly changing situation faced by the rescuers at the mine. Instead of decisions being made at Pike River, where mining and rescue experts were gathered, many were made by non-experts in Wellington.
This slowed the emergency response and could have impeded a rescue had one proved possible. Preparations to seal the mine to reduce the chances of further explosions were hindered, and some experts at the mine became disillusioned. The commission considers that management of the response over the crucial rescue period was not in line with CIMS principles.
International Journal of Mining and Mineral Engineering
The difficulties experienced highlighted the need for advance planning for an underground coal mining emergency, involving all the relevant agencies, including the MRS. After the explosions the mine entrances were sealed and inert gas was pumped underground. This extinguished fires and stabilised the atmosphere, which became methane rich and irrespirable.
Late that year the receivers, assisted by the MRS, established permanent seals that enabled the drift to be reclaimed and ventilated to m inbye of the portal. There is no prescribed timeframe and the risks involved in re-entering the mine workings beyond the drift make body recovery from this area very uncertain. A number provided written witness statements and some provided heart-breaking oral evidence to the commission. The commission was impressed with their fortitude and courage. The families were initially briefed twice daily by Superintendent Knowles and Peter Whittall, based on information they received from the mine site shortly beforehand.
Over the first weekend Mr Whittall in particular referred to fresh air being pumped into the mine, men waiting underground and the possibility of a rescue attempt when the mine conditions were better understood. The commission has concluded that Mr Whittall gave false hope, but did not do so deliberately.
Although some of his comments were over optimistic, even unwise, they reflected his state of mind at the time. Superintendent Knowles and Mr Whittall were at the mine at pm on 24 November when the second explosion occurred. Experts agreed that no one could have survived this even more forceful explosion. There are moves to involve government regulators in this, since it complements their role, and national mining associations. The data supplied by mines will be subject to a verification process.
Uranium is not a rare element and occurs in potentially recoverable concentrations in many types of geological setting. As with other minerals, investment in geological exploration generally results in increased known resources. This does not even take into account improvements in nuclear power technology which could effectively increase the available resource dramatically.
The vast majority is consumed by the power sector with a small amount also being used for medical and research purposes, and some for naval propulsion. Thus the world's present measured resources of uranium 5.
This represents a higher level of assured resources than is normal for most minerals. Further exploration and higher prices will certainly, on the basis of present geological knowledge, yield further resources as present ones are used up. All this was in response to increased uranium price in the market. However, the market price has since decreased, and uranium exploration activity has declined accordingly. Secondary supplies today account for the equivalent of about 12, tU per year.
A major secondary supply of uranium is provided by the decommissioning of nuclear warheads by the USA and Russia. Other sources of uranium include government and utility stockpiles and a very large amount of depleted uranium left over from historic enrichment, which can be re-enriched with more efficient processes. A little comes from recycled uranium from reprocessing used fuel. For detailed information about the main uranium mining countries, see dedicated country profiles.
The economics of mining uranium involves consideration of several aspects, starting with the country where an orebody is located, then the grade and nature of the ore, its depth, and also infrastructure issues. Countries have different degrees of sovereign risk affecting their attractiveness for mining investment, different royalty and tax regimes, and different availability of skilled workers.
These factors will already have influenced the mineral exploration which has led to the identification of an orebody before any question of mining has arisen. The quantity and nature of the ore is fundamental.
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The quantity, geological character and grade, along with its hardness and depth, determine what sort of capital investment is required. The mineral characteristics of the ore determine what sort of processing is required, and affect the cost of both capital and operation. Infrastructure issues include engineering and workforce.
A mine at a remote site costs more. Breaking down this set of considerations into conventional categories:. Taking all these into account, several escalating categories of cost reporting metrics can be distinguished:. AISC: All-in sustaining cost, including development and related costs to sustain future production. TradeTech has compared the cost profiles of a number of uranium mines for reporting their C3 operating costs per unit of output. In particular the comparison between open pit and in situ leach ISL operations is interesting.
Mining industry and sustainable development: time for change
It shows that for ISL mines, almost half the C3 cost is capital in setting up the operation, another quarter is sustaining it, and only just over one quarter is the basic C1 cash cost. This comparison This comparison underlines the need to be aware of what is included in any quoted production cost figures, though comparing C1 costs for very similar projects may be useful.
Ultimately, the economic viability of any mine depends on the C3 figures, but the difficulty in quantifying this at any point during operation means that a more realistic comparative metric is AISC. Among uranium-exporting countries, Australia and Canada have some of the strictest conditions relating to the use of its uranium.
These safeguards inspections and accounting procedures ensure that exported uranium is used for peaceful purposes only and is not diverted for military purposes or used in a way which adds to the proliferation of nuclear weapons. Bilateral agreements to this effect between the Australian and Canadian governments and each country wishing to import their uranium are therefore necessary before sales contracts can be completed. The further transfer of nuclear material is only permitted to countries which have bilateral safeguards agreements with Australia or Canada.
Australia, Canada and Kazakhstan are now the world's major producers and exporters of uranium. In addition to providing further diversification and strength to their domestic economies, it gives all three countries a voice in the framing of international nuclear policies and safeguards. It also reduces the need for buyers to seek uranium from countries with less effective safeguards. The atomic number of uranium is 92, meaning that it has 92 protons and occupies place number 92 in the periodic table.
What's Mine's Mine — Volume 1 on Apple Books
It occurs naturally in six isotopes, U to U and therefore contains between and neutrons. The most common isotope is U with a relative abundance of The second most common is U with a relative abundance of 0. All isotopes of uranium are radioactive and over time they decay to other lighter elements. However the rate of decay is slow; the radioactive half-life of U is 4. The half-life of U is million years which means that most of the Earth's original U has already decayed away.
A further property of U is that it is fissile and so neutrons emitted during fission can cause other U nuclei to fission also, releasing a lot of energy. It is mined and concentrated similarly to many other metals. Different kinds of mines Open pit and underground mining Where orebodies lie close to the surface, they are usually accessed by open cut mining, involving a large pit and the removal of much overburden overlying rock as well as a lot of waste rock.
In situ leach ISL mining Some orebodies lie in groundwater in porous unconsolidated material such as gravel or sand and may be accessed simply by dissolving the uranium and pumping it out — this is in situ leach ISL mining also known in North America as in situ recovery - ISR. Heap leaching Some ore, usually very low-grade below 0. Milling and processing Conventional mines have a mill where the ore is crushed and ground to liberate the mineral particles, then leached in tanks with sulfuric acid to dissolve the uranium oxides.
The solvents are then stripped in a countercurrent process using ammonium sulfate solution. Tailings management and mine rehabilitation From open cut mining, there are substantial volumes of barren rock and overburden waste. Precautions taken during the mining and milling of uranium ores to protect the health of the workers include: Good forced ventilation systems in underground mines to ensure that exposure to radon gas and its radioactive daughter products is as low as possible and does not exceed established safety levels.
Efficient dust control, because the dust may contain radioactive constituents and emit radon gas. Limiting the radiation exposure of workers in mine, mill and tailings areas so that it is as low as possible, and in any event does not exceed the allowable dose limits set by the authorities. In Canada this means that mining in very high-grade ore is undertaken solely by remote control techniques and by fully containing the high-grade ore where practicable.
The use of radiation detection equipment in all mines and plants, often including personal dose badges. Imposition of strict personal hygiene standards for workers handling uranium oxide concentrate.
Commission's Report - Volume 1
Sustainable development reporting and audit As well as international quality control standards such as ISO applying to environmental management at many mines, there is now emerging an industry audit framework in collaboration with consumers of uranium, especially utilities which are sensitive to sustainable development principles, including those of their suppliers. Economics of Nuclear Power. We wish to acknowledge and thank the many people who have assisted us with our inquiries, and our counsel, executive director and staff who have worked so hard.
We wish to acknowledge the families of the deceased men. We were impressed with their fortitude and courage. The commission would also like to acknowledge John Haigh QC, who died during the course of the commission.
The lessons from the Pike River tragedy must not be forgotten. New Zealand needs to make urgent legislative, structural and attitudinal changes if future tragedies are to be avoided. Government, industry and workers need to work together. That would be the best way to show respect for the 29 men who never returned home on 19 November , and for their loved ones who continue to suffer. Justice Graham Panckhurst.
Two men escaped the mine; the rest were missing:. WHEREAS on 24 November , before the mine was declared safe for search and rescue operations, a further explosion occurred that was of such severity that expert assessment was that none of those trapped underground could have survived:. And, without limiting the order of reference set out above, We declare and direct that this Our Commission also requires you to make recommendations upon or for —. But, We declare that you are not, under this Our Commission, to inquire into and report upon the wider social, economic, or environmental issues, such as the following:.
And We declare that, in this Our Commission, unless the context otherwise requires, practices includes, without limitation, each of the following however described :. And for better enabling you to carry this Our Commission into effect, you are authorised and empowered, subject to the provisions of this Our Commission, to make and conduct any inquiry or investigation under this Our Commission in the manner and at any time and place that you think expedient, with power to adjourn from time to time and from place to place as you think fit, and so that this Our Commission will continue in force and that inquiry may at any time and place be resumed although not regularly adjourned from time to time or from place to place:.