B) washed d) wash

Exercise 12. Put special questions to the underlined words. 1. The effects of oil spills depend on a number of factors, namely type of oil spilled, amount, weather conditions, etc. 2. Crude oil and refined oil inlude hundreds of substances with different properties. 3. The floating substances are gradually broken down by bacteria. 4. Oily coating destroys the animals' natural insulation and buoyancy. 5. 150.000 - 450.000 marine birds in the North Sea and the North Atlantic regions are killed each year by chronic oil pollution. (2 questions)

Exercise 13. Give definitions for the following terms.

Crude oil. aquatic organism, sheltered area, ecosystem, oil spill.

Exercise 14. Read the following text and translate it in a written

Form.

Environmental Concern

By 1970 the petroleum-refining industry had become well- established throughout the world. Demand for refined petroleum products had reached almost 2.3 billion tons per years (40 million barrels per day), with major concentrations of refineries in most developed countries. As the world became aware of the impact of industrial pollution on the environment, however, the petroleum-refining industry was a primary focus for change. Refiners added hydro-treating units to extract sulfur compounds from their products and began to generate large quantities of elemental sulfur. Effluent water and atmospheric emission of hydrocarbons and combustion products also became a focus of increased technical attention. In addition, many refined products came under scrutiny. By the mid 1970s petroleum refiners in the United States were required to develop techniques for manufacturing high-quality gasoline without employing lead additives, and by 1990 they were required to take on substantial investments in the complete reformation of transportation fuels in order to minimize environmental emissions. From an industry that produced a single product (kerosene) and disposed of unwanted by-product materials in any manner possible, petroleum refining had become one of the most stringently regulated of all manufacturing industries, expending a major portion of its resources on the protection of he environment.