What are tailings facilities?
A tailings storage facility (TSF) is a structure made up of (one or more dams) built for the purposes of storing the uneconomical ore (ground up rock, sand and silt) and water from the milling process. Tailings.
How are tailings dams built?
Upstream construction begins with a starter dam. The tailings are then discharged into the facility where they form a tailings beach. The deposited tailings adjacent to the dam wall is allowed to drain and then can be compacted to be used to form the foundation for subsequent levels of the wall as the dam is raised.
What is Gistm?
As a member of the ICMM, Gold Fields helped formulate the Standard, fully endorses it and will now commence with its implementation through its ICMM membership commitment.
What are the problems with tailings?
Tailings can contaminate aquatic life with toxic heavy metals and milling chemicals. Some metals, particularly mercury, may bioaccumulate up the food chain, ultimately harming humans. It causes turbidity (murkiness from suspended particles) and reduces oxygen levels which directly impacts aquatic life.
How are tailings stored?
Tailings are generally stored on the surface either within retaining structures or in the form of piles (dry stacks) but can also be stored underground in mined out voids by a process commonly referred to as backfill.
What are tailings used for?
Tailings ponds are used to store the waste made from separating minerals from rocks, or the slurry produced from tar sands mining. Tailings are sometimes mixed with other materials such as bentonite to form a thicker slurry that slows the release of impacted water to the environment.
What is the purpose of a tailings dam?
Tailigns dams are embankment dams constructed to contain and store waste (tailings) of mines. During mining, in order to separate the mineral or metal from the rock, mechanical and chemical processes are used to grind up rock into sand.
How much does it cost to build a tailings dam?
Tailings dams are an economic solution to the management of refuse. The cost of tailings dams is somewhere in the range from $1 per tonne to $5 per tonne of tailings deposited, and, adding societies true cost, it could be argued the cost is actually between $2 per tonne and $10 per tonne.
What is the best treatment for GIST?
The targeted drug imatinib (Gleevec) is typically the preferred first treatment for most advanced GISTs. (The targeted drug avapritinib (Ayvakit) might be used instead if the cancer cells have certain changes in the PDGFRA gene.)
What causes GIST?
A small number of families have GISTs that are caused by a gene mutation passed down from parent to child. (See Gastrointestinal Stromal Tumor Risk Factors.) But most gene mutations related to GISTs are not inherited. These changes occur for no apparent reason, and are called acquired or sporadic.
How can we reduce the impact of tailings?
Accordingly, there is increasing interest by mining companies in ways to reduce the size of their tailings ponds, develop alternatives to maintaining large ponds of water, or even eliminate them entirely. This can help them move towards the elusive goal of “walk-away closure.”
Why do tailing dams fail?
The causes of mine tailings dam failure are different as each failure is always site-specific, although common themes always emerge around: Poor site investigation. Inappropriate engineering design. Lack of risk assessment especially consequence analysis.
How are tailings disposed of?
The traditional means of tailings disposal is typically an impound method, often stored in a constructed dam in diluted form. This form of waste storage poses a number of concerns, the biggest of which is safety.
How long do tailings dams last?
According to mining engineer David M Chambers of the Center for Science in Public Participation, 10,000 years is “a conservative estimate” of how long most tailings dams will need to maintain structural integrity.
What chemicals are in tailings?
Tailing ponds are filled with toxic elements such as arsenic, cyanide, mercury waste, and other heavy metals with effects on the environment and human health.
Can tailings be recycled?
By reprocessing tailings, dewatering them and then storing them in a dry stack, mines can remove some of the economic, environmental and societal risks associated with tailings stored in slurry. The water recovered can then be reused, helping to drive down abstraction and logistics costs.
What are the environmental impacts of tailings?
When rain falls on tailings, it leaches away materials that can create water pollution, for example, lead, arsenic, and mercury. Sulfuric acid is sometimes produced when water interacts with tailings, or it can be a by-product of ore processing.
What is a downstream tailings dam?
Downstream tailings dams are raised progressively “downstream” of the starter dam, with an internal drain or filter. They often have an impervious layer (low permeability zone) on the upstream slope of the dam (labelled “core” in Figure 3).
How many tailings dams are in Australia?
In 2019 BHP announced that 32 of its 67 tailing dams were built using the upstream method and classified as ‘high risk or worse. ‘ Four of the five ‘extreme risk’ dams are in Australia – Mt Whaleback iron ore mine in WA and three at Olympic Dam in South Australia.
What drugs are used for GIST?
Drugs Approved for Gastrointestinal Stromal Tumors
- Avapritinib.
- Ayvakit (Avapritinib)
- Gleevec (Imatinib Mesylate)
- Imatinib Mesylate.
- Qinlock (Ripretinib)
- Regorafenib.
- Ripretinib.
- Stivarga (Regorafenib)
What is a Stage 4 GIST?
Conclusions: Stage 4 GIST is a rare gastrointestinal malignancy that most commonly manifests in the stomach and small intestine in male patients, with frequent hepatic metastases and excellent 5-year OS rates of up to 51%.
How are tailings managed?
Due to the nature of the ore separation processes, tailings are commonly in the form of a slurry of fine mineral particles and water. Management of tailings involves storage in a specially-designed impoundment called a tailings facility.
How do you handle tailings?
How to manage tailings efficiently and economically – YouTube
Which health and safety risk is associated with tailings dams?
Tailing dams contain liquids (toxic, hazardous, or even radioactive) which are pollutant sources of great damage risk to humans, the environment, and ecosystems [2]. Worldwide, at least 63 major tailings dam failures were reported that caused significant pollution during 1960–2014 [3].
What happens to tailings after mining is finished?
The leftover pulverized rock and liquid slurry become tailings, which often are acidic and contain high concentrations of arsenic, mercury and other toxic substances. Mining companies store tailings forever, frequently behind earth-filled embankment dams.