Application of Geotextile on Slope Stability for Establishment of Tailings Dam in Gold Mines – The Case of Hidden Valley Mine, Papua New Guinea

1. Introduction

The Hidden Valley (HV) tailings dam/storage facility (TSF – Fig.1) is constructed with downstream method of embankment. The initial dam crest elevation was designed for RL 2,000 with a storage capacity of 40Mt of tailings with a mill throughput of 4.2Mtpa, (Rynhoud et al., 2017). The TSF has reached its designed capacity at RL 2,000 and the mining company plans to raise the dam height to RL 2,015 to increase the volume. In this study, it proposes for further 20m dam height expansion in two stages (RL 2,025 & RL 2,035) with the application of geotextile reinforcements for slope stabilization.

Fig.1 Hidden Valley (HV) tailings dam

2.Numerical Simulation

Analysis of the TSF is carried out in 2 cross sections (Fig.2) with 4 stages (stg): RL 2,000(stg.1), RL 2,015(stg.2), RL 2,025(stg.3), RL 2,035(stg.4). Phase2 software is used for numerical simulations with: (1) no reinforcement; (2) geotextile reinforcement. Desired critical shear strength reduction factor (SRF) is 1.3 and above.

Fig.2 Model view of section AA' and BB' at RL 2,000

3. Results, Discussion and Conclusion

Fig.3 Stability of dam at different RL with no support

Fig.4 Stability of dam with reinforcements at different RL in X2

Fig.5 Effectiveness of reinforcements at RL 2,000 (X1)

It is unstable at initial stage with no support in X1(Fig.3). Geogrid and Geocomposites are unstable in X1, whereas structural interface is stable in X1(Fig.5). In X2, it is stable at initial stage, but unstable as the dam height increases (Fig.3). Geogrid and Geocomposites are stable at initial stage but, unstable as dam height increases (Fig.4). Structural interface is consistent and stable (Fig.4).

RL 2,035 is possible to achieve with the application of geotextile reinforcement in structural interface for stability in both X1 and X2.

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Small Scale Mining in Papua New Guinea

The Alluvial Mining Sector in Papua New Guinea (P.N.G.) contribute significantly to the country's economy. The gold produced by small scale miners eventually get to the gold exporters that in return bring in foreign currency into the country.

However, Mine Waste Management is an issue for almost all the miners in the country.

The mining operations contributes to the sedimentation that causes high turbidity of  rivers and streams where alluvial mining happens.

Luckily, most of the small scale mining operations use gravitational method and gold recovery where gold is physically separated from the gangue materials. Thus, least chemical is used. 

Below is a typical alluvial mining operation in PNG

 

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Clean up of Mine Waste in Papua New Guinea

 The Papua New Guinea's (PNG) Minister for Environment and Protection stated on the daily news paper dated October30, 2020 that an Hong Kong based company would be engaged to clean-up the mine waste in PNG at no cost to PNG government and the mining operators.

The company targets the river deltas where the Ok Tedi Mine and Porgera Mine dispose their mining waste. And the overseas based company is kind enough to clean up the mine waste in PNG.

The Minister may not be aware thinking that it is a good idea to get rid of the mine waste without realizing the value of the contents in it, Or he may be very well knowingly trying to get these assumed valuable residues from OK Tedi and Porgera which could be full of gold and other minerals. The Map interestingly showing the targets are Porgera and Ok Tedi river deltas. The foreign investor is not a non-sense to collect the mine waste from PNG deltas targeting Ok Tedi and Porgera tailings disposal rivers.  The tailings contain gold other gangue minerals which are unable to extract at the processing plants in both Porgera and Ok Tedi Mining.  And because both mines discharger their tailings into the river system, the sediments of these rivers (Strickland and Ok Tedi River) are rich in alluvial gold which can be extracted with improved techniques that can recover gold that are of fine particles.

 

It is good the company is interested in the mine waste disposal area and PNG should welcome the idea as it is an investing opportunity. however,  the company's approach is quite not right and must re-strategize and must make its hidden intention known by way of exploration proposal or Mining Proposal rather than saying they want to clean-up mine waste. They should apply for mineral tenement/leases and do the right thing with the PNG Mining Regulator which is Mineral Resources Authority.  

 

It must not be opposed but allow them to  progress and re-phrase to mine alluvial gold from  mine waste disposal areas rather then clean-up mine waste at the deltas. The deltas are rich in alluvial gold and industrial minerals if not known. It can only be proven with exploration and sampling.

Screen shot of The National News Paper publication..

 

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Tailings Dam Construction in Papua New Guinea a Challenge

Tailings dam constructions in Papua New Guinea (PNG) are faced with natural factors such as  high altitude with high rainfall (2000-5000mm), active seismic zone and other geotechnical structural factors which pose threat to the stability of tailings dam and potential failure.  As such, the PNG government has allowed mining companies to discharge tailings into the river systems over the last 30 to 40 years which pollutes the riverine and ecology within the vicinity of the mine impacted communities downstream.  However, the PNG Government intend to discourage riverine tailings disposal and encourage tailings dam construction in PNG.

The current tailings dams in PNG include Hidden Valley Tailings Storage Facility(TSF) and K92 Mine Tailings Dam.

The Porgera Gold Mine discharges its tailings into the Strickland River in the Enga Province. The Ok Tedi Copper and Gold Mine at the Mt.Fubilan, Tabubil in the Western Province discharges its tailings into the Ok Tedi River System.

The Lihir Gold Mine in the Luise Caldera of New Ireland Province places its tailings onto the deep sea floor (DSTP).

The Ramu Nickel and Cobalt Mine at Kurumbukari in the Madang Province also practice the deep sea tailings placement (DSTP).

The Wafi Golpu project is an advanced project with the Special Mining Lease Application lodged with the Mineral Resources Authority and is under technical appraisal by government at its engaged  independent consultants. This project proposed for a DSTP.

The Frider River Project proposed for an Integrated Storage Facility which will contain waste rock and tailings at the same time. The dam will also but used as hydro-dam to generate electricity.

The government of Papua New Guinea will never or might not allow riverine tailings discharge for all future mines in the country. It would be either by practice of building of Tailings Storage Facilities of place them one deep seafloor.

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Environmental Engineering Questions and Answers

1.       Define environment (in terms of mining).

Environment is Conditions that affect working atmosphere and development of mining. Or is the physical condition that exists in mines.

2.       What is mining?

It is the extraction of minerals from the earth.

3.       Why does environment become a subject to mining?

Because serious mine closure issues remain after mine is closed so by taking environment as a subject to mining, the mine closure issues can be addressed and must be known to the local people of what is going on and what preventive measures that can be taken to protect people and the natural environment.

4.       What are main sources of physical impacts by mining operations?

They are: exploration, development and extraction.

5.       What are main sources of chemical pollution due to mining?

Main sources of chemical pollution are cyanide and sulfuric acid for (leaching) and organic reagents (flotation agents) from ore separation processes. Others include mercury, toxic blast chemicals and hydrocarbon products run – off.

6.       What particular problem exists with both ferrous and precious metallic ores?

Acid mine drainage is a particular problem in many mines and both ferrous and precious metallic ores are the main sources of ARD.

7.       What is the main concern of trace metal concentrations?

The main concern of trace metal concentration is that, when they are leached into the river systems and streams it cause bioaccumulation which is a concern to the river systems.

8.       State the magnitude of mineral’s contributions to economic growth in developed and developing nations.

High proportions of minerals are mined in developing countries and so the economy of poor countries depends largely on minerals whereas minerals contribute a small portion to the economy of developed countries like USA, Japan and Great Britain.

9.       What are the effects of increased demand for minerals?

The demand for minerals increased as there was an increased in technology, development and human civilization. As a result, environmental impacts of earth based resource extraction increases.

10.   Why is every mine different and related environmental effects?

Because every mine has different characteristics with respect to environment. These characteristics include;

      Amount of materials removed.

      Deposit depth.

      Ore chemical composition

      Ore process technology/techniques

      Degree of stewardship practiced.

11.   Describe very briefly how mineral is extracted by surface mining methods and underground methods.

In surface mining method, the mineral is extracted by removing the overburden, drilled, blasted, loaded and hauled to the processing plant.

In underground mining methods, mineral deposits are extracted at certain depths. Ore is drilled and blasted stopes, marked and hauled to the surface via hoisting systems or diesel units.

12.   What aspect of operation distinguish surface from underground mining?

Underground mine operations are complex compared to surface operations. Surface mining is easy and cheap to operate because the ore deposit is near surface whereas underground mining is hard and expensive to operate because mineral deposit is at certain depth.

13.   State the natures of environmental impacts caused by mill operation, underground and surface mining respectively.

Riverine Tailings from mill operation is dangerous as most mineral deposits are associated with sulfur. In addition, smelting generate large amount of toxic gas. Smelters cause regional pollutions where SO2 can travel considerable distances and cause “acid rain” and climate change.

Potential sources of water pollution include drainage from surface and underground mines, waste water from beneficiation, and contaminated surface water from toxic blast chemicals and hydrocarbon products run – off.

14.   Why is chemical pollution more serious than physical?

Because chemical means are hard to reverse and these must be controlled at process stage. But environmental impacts through physical impacts can be reclaimed through rehabilitation during mining and post – mine period.

15.   Differentiate tailings and waste rock and describe respectively environmental impacts.

Tailings compose mostly of mud and slurry containing high proportion of fine particles. Mud and slurry tailings once exposed to air and rain cause oxidation, releasing sulfuric acid, causing acid rock drainage. The suspended solids cause river bed sedimentation, diversion of watercourses, flooding and destruction of aquatic life.

Waste rock is solid coarse materials from both surface and underground mines. Waste rock dump occupy large portions of land, often outside the special mining lease under lease for mining Purposes.

16.   If Frieda Copper mine is predicted to produce 1million/year ore at 0.45%Cu, what is the annual waste material generated?

Data: production = 1,000,000 tonness/year

       grade = 0.45%

Annual waste generated =????

Copper concentrate = production x grade = 1,000,000 x 0.0045 = 4500 tonnes copper.

Annual wastes = 1,000,000 – 4,500 = 995,500 tonnes of waste.

17.   If Hidden Valley mine has minable ore of 5minllion tones grading 2.5g/t Au, for mine life of 10 years, the tailings dam should be designed to what capacity?

Data: mineable ore = 5 million

Ore grade = 2.5g/t     mine life = 10 years.

 /year x 2.5g/t = 12,500,000 grams/year.

Total value mineral = 10 years x 12,500,000 gram/year = 125,000,000 grams

 In terms of tonnes = 125 tonnes.

Waste and value minerals = 5,000,000 tonnes /year x 10 years = 50,000,000 tonnes of ore.

Therefore; total waste generated would be = 50,000,000 tonnes – 125 tonnes = 49,999,875 tonnes.

So the tailings dam should be designed in such a way that will cater for 49,999,875 tonnes of waste over the ten year period. If tonnage factor was given then the answer would be expressed in volume.

18.   What is beneficiation? Describe it?

Is the entire process of crushing, grinding, sizing and separation of ore into valuable mineral and waste

In other words it is the process that liberates mineral grains locked in rock/ore which can be separated physically and chemically.

19.   State the two types of mineral separation and examples of each.

Two basic means of separation are physical and chemical.

·         Physical separation involves; - (a) magnetic and (b) gravity separation.

·         Chemical separation methods are: (a) floatation (b) cyanidation (c) amalgamation and (d) heap leaching.

20.   Briefly describe the processes: (a) heap leaching (b) cyanidation & (c) amalgamation.

      Heap leaching – is a process used to extract metal values from run – of – mine ore. The ore is usually porous and readily soluble in aqueous solvent.

      Cyanidation – is a process for extracting gold or silver from ore by treating the ore with a weak solution of sodium cyanide and recovering the metal particles from the resulting solution.

         Amalgamation – is a method of extracting a precious metal from an ore by using mercury to form an amalgam (an alloy of mercury and another metal) with the metal.

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Mount Crater Gold Mine in Papua New Guinea

Crater Gold Mine is located in the western part of Eastern Highlands Province in Lufa District,
adjacent to the eastern border of Simbu Province bordering Kramui Nomane District. It is centered
50 Km southwest of Goroka, the capital town of Eastern Highlands Province.

The closest airstrip is the Guasa Airstrip. From Guasa airstrip it will take you about 2 - 3 hours walk up the steep hills and along the fast flowing rivers. The site is ussually assessed by shopper.

ML510 was granted to Anomaly Limited in November 2014 to carry out a small scale underground
mining and processing operation at Crater Mountain.

Prior to the Mining Application and due processes were followed for granting, there was an exploration license EL 1115 which was known as Nevera and Nimi Prospects. The exploration could have started long ago back in the 1980s and various  PNG National geologists as well as foregne geologist can recall this prospect. The EL 1115 started in 1994 when the exploration licence was granted initially to MACMIN and then jointly explored by BHP. It was then to Anomaly Limited. Anomaly then tirelessly continued the exploration until the mineral resource was defined and further intended to apply for a mining lease to developed the ore body which was defined.

Mineralisation is typically confined to veins and thus dictate the Mining Method to be sub-level caving. The operation utilities hand-held  rock drills and jack picks. Broken ore is transported via mini rail cars to surface for processing.

Tailings discharge from the mill is collected in a sump where solids settle and the water overflow is
channelled into a second sump to further settle any silt and clear water overflows out to the nearby
creek. The solids in the sumps are harvested periodically and stockpiled for further processing at a
later stage.

Thus, it is believed that mine waste is managed within the vicinity and less environmental impacts are anticipated in this operation.

Photo Courtesy of Anomaly website

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Applications (Uses) of Zeolites in Civil Construction and other Fields

Besides the widely usage of zeolites in the Livestock and Agriculture Industries, it is also utilized in the civil constructions and other technological fields as well.

To begin with, zeolites can also be used for separating oxygen and nitrogen in the air to produce oxygen-enriched gas. This technology utilizes the strong absorbability of mordenite to nitrogen molecules to generate oxygen continuously which is vastly depend on the device and can also produce nitrogen as well.

Zeolite rock/ore is generally soft but not fragile is used as teaching material for carving for school children and is also used as cleanser.

One of the new applications of zeolites is in food packaging materials that are made of polyethylene film incorporated with zeolites was developed with an aim to retain the freshness of food or fruits and vegetables.

One of the most important applications of zeolites is in the civil constructions. In civil constructions, zeolites are used as new lightweight building materials such as plastic filler and plywood adhesives. Further to the lightweight, zeolites are also used as foam blocks incorporated in linings of chimneys of thermal plants and dolomite plaster.

Similar to zeolite, siliceous mud-stone is utilized in such applications as soil conditioners, deodorizers (for environment improvement of poultry and pig farms), and special fertilizers.

Siliceous mudstone is also referred to as “crystobal rock” which contains a lot of crystobalite composed of silica (SiO₂).

Zeolite is used in a wide range of applications and among them is the clay for papermaking which was developed in Japan. Zeolite is soft and its powder is significantly white and it is applied to papermaking to take advantage of its properties. Zeolite clay is serving as a filter which provided paper with high opacity and excellent ink acceptance.

Synthetic zeolite was invented by German Professor Gans in 1905, and was first named permutit and after permutare, a Latin word meaning exchange. Permutit has a composition of Na₂O.Al₂O.xSiO₂.yH₂O and strong adsorbability.

Crushed Zeolite Materials ready for loading

References:

Boiling stone (zeolite), Zeolite Dynamics, Lecture Notes.

Nouko to Engei (Agriculture and Horticulture), September 1978.

JACK News

Materials for Zeolite Forum (1989)

Survey by Zeolite Industrial Association

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Applications (Uses) of Zeolites in the Livestock and Agriculture Industries.

Zeolites are widely used in the livestock and agriculture industries among other uses. In this article, it discusses the common uses of zeolites in the livestock and agriculture industries. In the Livestock Industry, zeolite is purposely used for improving the growth and health of animals while in the Agriculture Industry, zeolite is used for the purpose of improving the fertility of the soil for healthy growth of cash crops.

The use of zeolites in the livestock industry is basically added to the livestock feed which absorb the toxins in the body of chickens and pigs and finally discharge them out of the body.

Furthermore, the minerals contained in the zeolites actually promote the growth and health of livestock. That is, zeolites adsorb the stench of ammonia to improve the environment and also function as drying aids by virtue of their ability to absorb moisture. Thus, cat litter (litter for pets) utilize such properties of zeolites for optimum benefits.

In the Agriculture Industry, it utilizes the properties of zeolites such as the adsorption capability and Base Exchange capability which prevent the outflow of fertilizers by absorbing the components of fertilizers as well as improving soils by neutralizing soils containing acids or acidic soils. Zeolites also have excellent absorption ability and water retention capacity which make them more effective in preventing either drought or cold weather impacts of any kind cause by nature.

Estimation of cation exchange capacity of zeolite is much more difficult as it is closely related with qualities from its appearance. As such, zeolite powder is not readily distinguished from other rock powder.

Zeolite is specified as land improvement material by a Cabinet Order based on the Soil fertility Enhancement Act (Act No.34 of 1984) in order to assure the quality. According to Cabinet Order, the zeolite must meet the criterion “cation exchange capacity (C.E.C.) per 100 g of dry matter is 50g or more.”

Moreover, the applications or uses of zeolites range from water purification for fish farming to pollution prevention exercises. The water purification for fish farming refers to a function to adsorb ammonia and hydrogen sulfide in water which produces purified water.  In addition to that, zeolites have an effect of softening hard water to stabilize pH.

Besides water purification for fish farming, zeolites are also used for pollution prevention in the following fields:

·         Purification of hazardous components in industrial wastewater.

·         Adsorption treatment of heavy metal ions from abandoned mines.

·         Removal of heavy metals from plating waste.

·         Decolourization of waste water from dye houses.

·         Prevention of eutrophication of lakes and marshes caused by ammonia nitrogen.

·         Removal of harmful components from automobile exhaust gas.

The supply of zeolites depends entirely on clients' demand and off course consumption rate. Supply of zeolites is also dictated by scale of mining operation and processing.

Zeolite ore (rock)

References:

Boiling stone (zeolite), Zeolite Dynamics, Lecture Notes.

Nouko to Engei (Agriculture and Horticulture), September 1978.

JACK News

Materials for Zeolite Forum (1989)

Survey by Zeolite Industrial Association

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Data Analysis of Rapid PACKTEST Results

Upon the completion of the setup and PACKTEST, you have the data available at hand to record. In your note book you record the readings of pH, Turbidity, Temperature, metal conductivity. Then you have the other sets of data from the PACKTEST results. Each element tested has got a numbered color range that corresponds to the concentration of that element/compound in the water sample. You record every data for the elements that are tested.

Finally, you need to digitize the data and analyze the test results. To do that, you need to have a computer or a laptop. Create an excel spread sheet in your laptop or computer and enter the field data in a tabulated format. Your sample results look like the table below:

Table 1 Rapid PACKTEST Results

Now, data analysis is the comparison, verification and few comments or conclusion drawn from the raw data collected from various spots/sites which are tabulated like Table 1 (above). A good analysis of data/ results is always a careful comparison and contrast in the data obtained by plotting the data in different graphical methods.

Be careful to graph the related data so that any conclusion drawn can make sense with respect to particular information. i.e. if you plot all the data into one graph then always take note of the legends so that your interpretation is accurate in reporting.

It is also better to take readings at different weather patterns i.e. during rainy seasons and dry seasons. Remember to keep the sample points unchanged so that a good comparison is made.

From the data analysis, it is better to make few comments and off course a recommendation is anticipated from the field investigation. Your recommendation should provide a clear direction/ indication should there be precautions taken within the vicinity of the impacted project area especially the mine impacted communities. Your recommendation should also alert the local government authorities regarding the findings and what to do in that part of the area.

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Characteristics of Zeolite Ore

• Like any other matters, Zeolite has two major characteristics which are:

1.      a chemical composition having zeolitic water, and

2.      An excellent ion exchange capability.

Zeolitic water is unique in the composition which is hardly observed in other minerals, as dehydration occurs without changing the crystal structure under heating. This hydration behaviour enables zeolite to be used as moisture absorbent.

In addition, the dehydrated zeolite has a myriad of holes like a honeycomp and the holes have such small sizes in the order of angstroms (Symbole:Å, unit cm/100 million). Accordingly a mixture of gasses with different molecular sizes, which are chemically difficult to separate at the molecular level, can be sieved through zeolite. This is called the “molecular sieve effect.”

The Cation exchange capacity of zeolite is explained as follows:

The general chemical composition of zeolite in general is indicated by

(M²⁺,M₂₊)O.Al₂O₃.mSiO₂.nH₂O. The symbols in the parentheses at the beginning of the formula indicate exchangeable cations. Cations in zeolite are exchangeable with other cations in aqueous solutions. In chemical terms, material with a positive charge is referred to as a base. The ability to exchange bases is Base Exchange capability (or cation exchange capability), while the capacity to exchange bases is base exchange capacity (or cation exchange capacity) and is called C.E.C., the acronym for “Cation Exchange Capacity.”

Ion exchangeability allows silicon (Si) atoms located in the centre of the zeolite crystal lattice to be partially replaced with aluminium (Al) atoms, resulting in the loss of cations. Cations such as sodium (Na), Calcium (Ca) are captured in the crystal lattice to compensate for the shortage.

The function of C.E.C. is similar to that of the liver of an animal which stores nutrients. Zeolite adsorbs and stores fertilizer components (bases) such as sodium, potassium and calcium to supply the nutrients (fertilizer components) to crops in response to request.

The unit of cation exchange capacity is represented by mg equivalent (meq) per 100g of soils or zeolite rocks.

The cation capacities of clay minerals are different depending on the type of minerals. Montmorillonite is the main mineral source for bentonite which exhibits the highest C.E.C. after zeolite.

Reference:

Boiling stone (zeolite), Zeolite Dynamics, Lecture Notes.

Roskill Report (1990)

Annual Reports of Various Companies.

Nouko to Engei (Agriculture and Horticulture), September 1978.

JACT News.

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Zeolite (Boiling Stone) Ore

Zeoilte (Boiling Stone) Ore

Zeolite is a term referred to as Boiling Stone. The Term Zeolite is derived from two Greek words Zeo (to boil) and Lite (a stone).  The heated ore supported at the tip of a blowpipe which is used for qualitative research is observed to swell into a pumice-like porous state when air is blown from the mouthpiece. The phrase boiling term comes from this behaviour.

Zeolite is an aluminosilicate mineral (silicate in which silicone atoms are partially replaced with aluminium atoms) containing maily alkali metals such as sodium and potassium and alkaline earth metals such as calcium and magnesium, as well as water molucules (H₂O) in the form of crystals.

(M²⁺,M₂₊)O.Al₂O₃.mSiO₂.nH₂O

M^2+: Mainly Calcium (Ca)

M⁺: Mainly Sodium (Na), Potassium (K)

Zeolite commonly occur in pores of volcanic rocks or inside the rocks in the shape of veins, and are found in the strata near metal ore deposits as well as geothermal power plants and hot springs. Volcanic glass in tuff often transforms into zeolite under the influence of seawater. As a result, besides pure zeolite components, zeolite rock contains minerals such as clay (montmorillonite), iron oxide and feldspar.

Generally, zeolite will generate different zeolite crystal structures, even if it is from the same origin rock, depending on the burial depths, with the pressure on the rock increases to affect the crystal structure with and aid of ground water and hot water. Natural

Among many minerals, the widely distributed natural zeolites are clinoptilolite (often called ‘clino’) and mordenite.

Laumontite is a white plate-like or columnar crystal. Laumontite, which is formed primarily by the action of hot spring water, replaces minerals in rocks or fill cracks making a pattern of veins. Laumontite can be found in aggregates (or gravel) in concrete.

Laumontite is said to react with alkali in cement (alkali-aggregate reaction) to inflate the aggregate which cause cracking.

Applications of zeolite will be in the next article.

Reference: Boiling stone (zeolite), Zeolite Dynamics, Lecture Notes.

Zeolite ore 

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How to Conduct Rapid PACKTEST in a Well (below 1 meter in depth)

Well is simply a shaft sunk into the ground or built upwards from certain depths below a natural surface of the ground which extends further above certain heights of the natural surface of the ground 

Wells can be naturally occurring or man-made. Man-made wells are created to suite the desired purpose(s) of the organisation or individuals. Wells can be created to collect water or oil or gas below the earth’s surface.

In a mining operation, wells are created for the purposes of heap leaching through a vat. Heap Leaching is one of the various mining techniques to extract gold from the ore of various host rocks using cyanide which is one of the common solvent in this gold recovery technique.

During the gold recovery process, cyanide is sprinkled over the heap of crushed gold bearing gravels (ore) to dissolve the gold into a pregnant solution or into liquid form. The pregnant solution is then sucked out through the vat and further into carbon columns and take to the processing plant for further processing and smelting.

Upon the closure of the mine, the vats are no longer in use. Cyanide is left behind the pool beside the heap-vats eventually gets into the surrounding environment which is a concern for mine waste management. Water is then filled through the Vats up to certain heights.  So from the top and surface of the heap-vats, the water level is below certain depths of about 2 – 3 meters which are hardly reached by hand. And also the diameter of the vats is about 30-40 cm which is too narrow to be accessed. So how can you how can you overcome this challenge to take a water sample for a Rapid PACKTEST as well as other measurements?

The simple way to get sample is by utilizing the following equipment procedures:

1.     String line (rope)

2.     Metal weight(1kg weight)

3.     3x1 Litre plastic bottle(container)

4.     Masking tape

5.     Water level measuring tape

6.     GPS

7.     Note book, pen, pencil

8.     Camera

9.     Blade/kitchen knife

10. PACKTEST kits

11. Syringe

12. 0.45µm filter

13. turbidity meter

14. pH meter

15. Laptop/computer

 Procedure

1.     Cut the 1 Litre plastic bottles (container) into more than half.

2.     Tie the 1kg metal weight at the tip of the string line.

3.     With the masking tape, fasten the cut container with the weight attached to the string line.

4.     Drop the container attached to the weight and stringline into the well and allow the container to be filled with water.

5.     Pull the string line with all its attached items and pour the fetched water into the other reserved containers.

6.     Never forget to measure the water level by using the 50m water level measuring tape.

7.     Using the GPS you take the readings of sample location coordinates and altitude and location zone.

8.     Finally , you conduct Rapid PACKTEST and

9.     Turbidity and pH measurements, conductivity and temperature readings as well.

The above procedure can be repeated for wells or pools that are hardly accessible in person or by hand.

Data Collection of the Rapid PACKTEST is the final thing to do before moving to the next location or ending the field work.

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