Fig. 34. Example of exploitation plan

COMPREHENSION CHECK

Exercise 8. Complete the sentences using the information from text 2:

1. The water required … … varies very greatly according to the characteristics of the gravel to be treated.

2. It should be mentioned that … … through various sluice boxes, the river water will carry a great deal of fine silt.

3. … … a series of dams across the valley, it is possible to exploit various sections of the payable ground.

4. Gravel is loaded … … by shovel.

5. … … operations it is essential to keep a record for each area … done, … employed.

6. Overburden and gravel is … daily.

Exercise 9. Answer the following questions based on the information found in texts 1 and 2 and on your own experience.

1. What does the term “sluicing” mean?

2. What stages does alluvial mining consists of?

3. Is sluicing the simplest and cheapest method for working shallow alluvial deposits?

4. How are sluice boxes made?

5. Where can sluice boxes be rigged up?

6. Where are tailings discharged?

7. In what way is it possible to exploit various sections of the payable ground?

8. What method may be used when water is very scarce?

9. Where may ground sluicing be employed?

10. What does this method of sluicing consist of?

11. What can you say about the necessity of records?

LANGUAGE REVIEW

Exercise 10.

1. Fill in the missing forms of the words:

verb	noun	adjective
…..	smelter	-
add	…..	additional
signify	…..	significant
…..	responsibility	responsible
compose	…..	compositional

2. Fill in the blanks with the words above

1. The mining process and waste pose ______ hazards for our air, water, soil and forests.

2. The ______ heats the ore to a temperature at which the metal _______.

3. Construction of the mine depends on existing geological barriers, as well as the physical _______of the gold ore.

4. Mining companies are ________ for restoring the land they have worked on.

5. Open pit gold mining is another industrial method of obtaining gold from the earth. It involves a chemical process in _________ to the mechanical task of removing rock.

Exercise 11. Render in English

Не все аллювиальные месторождения можно разрабатывать гидравлическим способом, в этом случае можно применять обычный шлюзный метод.

Количество шлюзов, которые можно использовать, зависит полностью от количества воды, имеющейся в наличии. Этим методом можно обрабатывать примерно 7-10 ярд³ на одного рабочего, в день на одной линии.

UNIT 7

HYDRAULIC MINING

PRE-READING

Exercise 1.

1. Do you agree that the process of mining for gold begin with a pickax and shovel?

2. Which ore indicates that gold may be in the area?

Exercise 2. Match the words and their synonyms:

sludge equipment recovery determine quantity

amount facilities mud extraction define

READING

Exercise 3. Read the text and learn more about the process of gold mining

Text 1. The Process of Mining Gold

Where to Dig

Today the process of mining for gold is very complex. It does not begin with a pick ax and shovel and hopes of striking it rich. It begins with a well thought out plan. First, a company will secure the funds and backing to set up the necessary equipment and carry out the recovery of the gold should it be found. Then they will employ geologists and specialist to analyze the rock contents in a particular geographic area. The specialists look for things like igneous rocks, quartz and ore which indicates gold may be in the area.

Starting the Extraction

If there is determined to be enough probability to find a large amount of gold in the area, the gold mining company will begin their operation. Today, large machines are used to grind away rock, ply away soil and basically strip down the earth until they reach the "pockets" where gold is located. In some cases, this requires drilling through solid bedrock, and then creating a mine shaft with specialized digging equipment. The mine shaft is built to intersect the gold pockets, and workers are then dispatched to extract the gold.

Recovery

Sometimes gold is spread in very thin quantities throughout the ore in the soil. In this case extraction methods are used to remove the gold from the dirt. Once the gold ore is removed from the ground, the rocks are sorted and crushed into fine powder, then this is mixed with a solution and turned into sludge. The sludge is stored in tanks and then sent through a "clarifier" and finally through a filter where the gold is separated from the liquid and recovered. (http://www.goldgold.com/)

COMPREHENSION CHECK

Exercise 4. Are the statements true or false? Correct the false statement using the facts from text1.

1. The process of mining for gold is not a simple one.

2. Specialized digging equipment is used to remove gold from the ground.

3. Extraction goes after recovery.

4. Sludge is a mixture of rock powder and a solution.

VOCABULARY

auriferous - золотоносный

сhannel – желоб

denuding - десорбирование

exposing - обнажение

dump - отвал

gravel banks – насыпь песка

head - напор

jet - струя

pipeline - водопровод

bedrock – коренная порода

tailings - хвосты

giants - гидромонитор

nozzle - насадка

vanes - лопасти

exert - усиливать

thurst – напор струи

horse-shoe - башмак

Exercise 5. Find the meaning of the word combinations in the dictionary and try to remember them:

remove; removal; occur; bank; gravel banks; abundance; dump; avoid; design; range; to range; to force; head; to direct; lever; to operate; to place; care; to care; immediately; main; put; consider; bedrock; to employ,' to disintegrate; to drive; size; available; jet.

Exercise 6. Fill in the blanks with one suitable word:

1. The four essentials for successful hydraulic mining are: abundance of ...; abundance of ...; a good ...; a properly constructed ...

2. Giants or monitors as they are generally called, … for … .

3. A small amount of water under … ... will excavate as much material as a large amount of water under ... … .

4. The timber should be well ... … down or else ... to bedrock.

5. Small giants and those working under a low pressure are directed by ... .

6. In actual mining operations with a giant, work should generally be commenced at the ... part of bedrock, and the giants placed at a distance of from ... to ... feet from the base of the banks.

READING

Exercise 7. Read the text below looking for the main ideas of hydraulic mining.