Environmental Effects of Offshore Drilling and Production Reading Answers

Answer: D
Supporting sentence: oil often exists in the surface at great pressure and, in the early days when wells were drilled with only air or water in the hole, the oil could rush into and up the hole and blow out at the surface.
Keywords: drilled, blow out, oil
Keyword location: 1st paragraph, 2nd line
Explanation: As was said in the first paragraph, water and air are forced out of wells when they are drilled because of the high pressure that the oil is under at the surface.

Answer: B
Supporting sentence: Modern drilling rigs are also fitted with blowout prevention controls: a complex system of the metal clamps and shutter which can be used to seal the hole if unexpected high pressures are encountered.
Keywords: high pressure, metal clamps
Keyword location: 2nd paragraph, 1st line
Explanation: The sentence above describes how the metal clamps and shutter are utilized to regulate this unexpected high pressure, which eventually results in the blowout being avoided.

Answer: C
Supporting sentence: offshore drilling commenced in Australia in the mid 20th century, there has not been a single oil blowout. On the other hand six gas blowouts occurred during that time: five in the Bass Strait One in the Timor sea. The Bass Strait Blowouts were controlled relatively quickly; the Petrel well in the Timor Sea flowed gas for 15 months.
Keywords: blow out, Australia
Keyword location: Paragraph 3, 2nd line
Explanation: According to the text, all six gas blowouts were swiftly contained; therefore, it is possible to conclude that offshore drilling in Australia in the middle of the 20th century prevented blowouts.

Answer: 10 kilolitres/63 barrels
Supporting sentence: largest single spell in kiloliters (barrels)
Keywords: largest single spill
Keyword location: Paragraph 2, last section the table
Explanation:The largest single oil leak has been discussed in the table's last section. In light of this, the answer is 10 kilo liters.

Answer: 6
Supporting sentence: On the other hand six gas blowouts occurred during that time:
Keywords: blowout
Keyword location: Paragraph 3 and table 2
Explanation:Six instances occurred as a result of a blowout around the middle of the twentieth century, as noted in the table under paragraph 2 and in passage 3.

Answer: Platform oil spill
Supporting sentence: 2nd row of the table
Keywords: spill
Keyword location: Paragraph 2, the second section of the table
Explanation: The second half of the table in paragraph 2 demonstrates that the Platform oil spills, which had a count of 27, are responsible for the majority of the oil spillage. Consequently, an oil spill from a platform would be a suitable response.

Answer: local food chain
Supporting statement: this material is diluted rapidly and contributes to the local food chain without any risk of nutrient oversupply.
Keywords: nutrients
Keyword location: paragraph 5, 2nd line
Explanation: It is possible to infer from the preceding sentence that putrescible waste is directly dumped into the ocean, which in turn serves as a source of nutrients for the local food chain. Consequently, it is the proper response.

Answer: solid waste
Supporting statement: material is diluted rapidly and contributes to the local food chain, without any risk of nutrient oversupply. Therefore, all solid waste must be brought ashore.
Keywords: ashore, solid waste
Keyword location: Paragraph 5, 2nd line
Explanation: From the passage, it could be inferred that all waste in concrete form is dumped into the ocean without first being collected on the shore.

Answer: cuttings
Supporting statement: cuttings are sieved out of the drilling fluid and usually discharged into the ocean.
Keywords: discharge, ocean
Keyword location: Paragraph 6, 1st line
Explanation: This sentence in the paragraph discusses a different discharge that is being poured into the water with the intention of engraving. So, this is the right response.

Answer: local and variable
Supporting statement: some benthic organisms may be smothered, but this effect is local and variable, generally limited to within above 100 meters of the discharge point.
Keywords: benthic organisms
Keyword location: Paragraph 6, 3rd line
Explanation: With the evidence provided, it is possible to draw the conclusion that some benthic animals suffer greatly as a result of the ocean's rain, but that the impact on the organisms is quite local and variable.

Answer: heavy metals
Supporting statement: most of the common constituents of water based fluids used in Australia have low to nil toxicity two marine organisms. Also, the small amount of heavy metals present are not absorbed into the bodies of marine organisms.
Keywords: heavy metals, water based fluids
Keyword location: Paragraph 7, 2nd line
Explanation: A very little amount of some heavy metals are present, but they are not ultimately absorbed into the bodies, based on the information provided in paragraph 7.

Answer: oil based drilling fluids
Supporting statement: oil based drilling fluids have a more toxic component and discharge to the marine environment is more significant. However they are used only rarely in Australia and the impact remains relatively local.
Keywords: marine environment, toxic component
Keyword location: Paragraph 8, 1st line
Explanation: Since oil-based fluids are poisonous by nature, it can be deduced from the information in paragraph 8 that they have a very detrimental effect on the marine habitat.

Answer: gas deposit
Supporting statement: produced water is the water associated with the oil or gas deposit and typically contains some petroleum, dissolved organic matter and trace elements.
Keywords: oil
Keyword location: Paragraph 9, 2nd line
Explanation: The water that is primarily connected with oil and gas deposits is generally non-toxic, as was mentioned in paragraph 9.

Answer: background levels
Supporting statement: most produced water is effectively non toxic but even when relatively toxic is quickly diluted to the background levels.
Keywords: non toxic, diluted
Keyword location: Paragraph 9, 3rd line
Explanation: According to the information in the paragraph, water is generally non-toxic, but it entirely loses its potency and becomes diluted when combined with background levels of other substances. Consequently, it is the right response.