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Lesson 3 Water problems

1. Mind the pronunciation of the words below.

abrasive [q'breisiv], erosion [I'rquZqn], chlorine ['klLri:n], disinfection ["dIsin'fekSn], bacteria [bxk'tiqriq], manganese ['mxNgqnJz], corrosive [kq'rqusiv], microscopic ["maIkrq'skopik], tannin ['txnin], type [taip].

2. Remember the following words and word combinations.

consumer – потребитель

appear – 1) появляться 2) оказываться

appearance – вид (внешний)

turbid =cloudy = foggy – мутный

be due to –быть обусловленным

finely divided = fine – мелкий ( о частицах)

sink – кухонная раковина

stain – оставлять пятна, разводы; пятно

fixtures – водопроводная арматура

wear – износ

objectionable – неприемлемый, неприятный

common – общий, обычный, распространенный

treat – обрабатывать, очищать

excess – избыток, излишек

manganese – марганец

plumbing – водопровод, водопроводная арматура

suspended – взвешенный, находящийся в суспензии

background – фон

tub – ванна

clear = transparent – светлый, прозрачный

exposed – открытый, подверженный воздействию

disadvantage – недостаток

hard water – жесткая вода

water softener – умягчитель воды (ионообменный)

water conditioner – преобразователь

жесткости воды (электромагнитный)

3. Watch out!

fabric – ткань, материя, а не фабрика

effect – воздействие, результат, а не эффект

real – истинный, настоящий, а не реальный

4. Text.

Turbidity (Cloudy Water) At one time or another, most consumers have encountered water that appears cloudy or foggy. This characteristic is due to turbidity: the presence of finely divided solid particles in water. These particles may be inorganic mineral matter which does not dissolve, or organic matter that has been picked up as the water flows over and through the ground. The particles cause the scattering and absorption of light rays, which gives the water a cloudy appearance. Whether turbidity is due to suspended organic or inorganic matter, it can cause staining of sinks and fixtures, and the discoloration of laundered fabrics. Inorganic turbidity can have an abrasive effect on plumbing systems and may cause physical wear or erosion on pipes and fittings. Turbidity is most commonly found at taps whose source is surface water from lakes, streams, or ponds.

Taste and Odour. Another set of problems that will quickly catch a consumer's attention is objectionable tastes or odours present in water. A common characteristic of water from public systems is the chlorine taste and odour, which is often quite noticeable. Many public water systems treat water with chlorine to disinfect it. Although this is an important step in the treatment of water because it destroys disease-producing bacteria and other harmful organisms that may be present in water, there is no doubt that excess chlorine from the disinfection treatment step can make the water objectionable. In other cases, water with a high mineral concentration may have an unpleasant soda or salty taste, and a metallic taste may be produced by the presence of iron or manganese in water.

Colour. Another very noticeable water problem is unusual colour, which can make the water unappealing for drinking, and may cause the staining of surfaces and materials that come into contact with the water. In some home water supplies, a yellowish coloration may be present. This colour condition is organic in nature, but presents no health hazard. It is caused by the presence of microscopic suspended particles. This coloration occurs in regions where the water passes through marshlands and has percolated down through peaty soils. It is most likely to be found in the Southeast, Northwest, New England and Great Lakes regions of the United States; and is more common in surface water supplies and shallow wells than in deep wells. Humic acids, often referred to as tannins, are the real cause of the colour condition. Often the colour is not highly visible in a glass of water, but can frequently be noticed when water is drawn for a bath. The white porcelain background of the tub can highlight even the slightest discoloration.

A more severe colour condition may be caused by the presence of iron in the water. The disadvantages of water containing significant amounts of iron are obvious. It can leave brown-red stains on fixtures and dishes, as well as discolour laundry. It is also unappealing for drinking.

Notes:

1. colour condition - цветность

2. humic acid – гуминовая кислота

5. Give English equivalents of the following.

опасность для здоровья, взвешенные частицы, органическое вещество, рано или поздно, мелкие твердые частицы, придавать воде мутный вид, обесцвечивание, разъедание труб, чаще всего, ещё один круг проблем, привлечь внимание потребителя, нет сомнения, высокое содержание минералов, образование пятен, металлический привкус, органический по природе, неприятный запах, болезнетворные бактерии, истинная причина, красноватый цвет.

6. Find synonyms.

consumer, cloudy, type, odour, characteristic, user, turbid, kind, smell, property, unpleasant, matter, objectionable, substance, to cause, because of, lead to, content, due to, another, concentration, one more, real, clear, significant, fine, considerable, finely – divided, true, transparent.

7. Choose one of the given variants to complete the sentence.

1. Turbidity is caused by _________ solid particles in water.

a) unpleasant

b) harmful

c) fine

d) dissolved

2. Water coloration can cause the ________ .

a) destroying of bacteria

b) staining of fixtures

c) failure of pipes

d) discoloration of laundry

3. Inorganic turbidity can cause _______ on plumbing systems.

a) discoloration

b) unusual tastes

c) objectionable odour

d) erosion

4. Water containing a lot of iron can ______ .

a) disinfect water

b) cause physical wear on pipes

c) make water turbid

d) discolor laundry

5. Water from a public system is primarily characterized by ________.

a) the chlorine taste and odour

b) colour condition

c) turbidity

d) significant amounts of iron.

8. Answer the questions below.

1. What gives the water a cloudy appearance? 2. What is the effect of turbid water on plumbing systems? 3. How do public water systems disinfect water? 4. Why is hydrogen sulfide detectable even in very low concentrations? 5. What regions is yellowish water typical of? 6. What are the disadvantages of water containing a lot of iron?

9. Translate the text below in the written form.

Hard Water Problems. Water described as "hard" means it is high in dissolved minerals, specifically calcium and magnesium. Hard water is not a health risk, but a nuisance because of its tendency to cause mineral buildup in water pipe and heating systems, and its poor soap and detergent performance when compared with soft water.

Water is a good solvent and picks up impurities easily. When it combines with carbon dioxide in the air to form very weak carbonic acid, an even better solvent results.

As water moves through soil and rock, it dissolves very small amounts of minerals and holds them in solution. Calcium and magnesium dissolved in water are the two most common minerals that make water "hard." The degree of hardness becomes greater as the calcium and magnesium content increases.

Traditionally the water treatment market had one main solution to hard water. This solution was water softeners. However, in recent years alternative treatments have become increasingly popular, the most interesting of which being electro-magnetic water conditioning.

Water softeners work by ion exchange, so sodium replaces the calcium and magnesium in the water. Water conditioners on the other hand create a magnetic field around your pipework which alters the ions in the water so that they lose their ability to cause scale. In tackling hard water, both methods will reduce limescale. Water conditioners are significantly less expensive and they have negligible running costs. Water softeners cost a lot more but they treat very small amounts of other metals such as copper, iron or zinc.