Self-study
P1
A major problem facing industrial societies is their exponentially increasing production of toxic waste. █████████████ ███████████ ███ ████████ ███ █████████ ███ ████████████ ████ █████████ █████████████ ██ ██████ ██████ ███
Main Problem ·
Toxic waste disposal
Solution ·
Deep well injection
Details of Solution ·
Details of deep well injection
Waste injected into rock layers, out of reach of underground drinking water (aquifers)
problem ·
Three problems with deep well injection
P2
█████ ███ ████ ███████████ ██████ ███ ████████ ████ ████ ██████ █████████ ████ ████ █████ ███ █████████ ██ ███████████ ████ ██████ ████ ████████ ██████████ █████████ ██████ ████████ █████████ █████ ███ █████ ████████ ███████████ ███████ ██ ███████ █████████ ██ ███ ████ ████████ ██ ████████ ██████ ███
Problem 1 ·
Wells can still leak into aquifers, polluting drinking water
Problem 2 ·
Human error can cause wells to fail
Example of human error threatening drinking water supply
P3
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Problem 3 ·
Very difficult to predict how waste will flow underground
P4
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Reiteration of 3 problems ·
Uncertainty of flow (problem 3), mechanical failure (problem 1), human error (problem 2)
Passage Style
Problem-analysis
Single position
1.
Which one of the following ████ ██████████ ██████ ███ ████ █████ ██ ███ ████████
a
Deep-well injection of █████████ ██████ ██ ██████ ████ █████████ █████████████ ████████ ███ ███ ██████
This isn’t the main point, because the author doesn’t emphasize the lack of expensive precautionary measures as a condition that would render deep-well injection of wastes unsafe. In fact, the author believes that deep-well injection of waste can be risky
b
Although deep-well injection ██ █████████ ██████ ███ ██ ███████ ██ ██ █████████ ████ ████ ██████ ██████████ ███ ████████ ███ █████ ███ █████████ █████████
The author’s point is that deep-well injection of wastes is risky. The author doesn’t suggest that this practice can ever be “generally safe.”
c
Because of the ████ █████ ███ █████████ ███████████ ██████████ ████ █████ ████████ █████████ █████████ ███ ██████ ██████████ ███████████ ███████ ██ ███████████████ █████████
This doesn’t capture the author’s focus on the risk posed by deep-well injection of waste. In addition, the author never suggests that deep-well injection has “wholly supplanted” (completely replaced) other methods of disposing waste.
d
The increasing use ██ █████████ █████████ ██ █ ██████ ██ ███████████████ ████████ ██ █████████ ████████████
This best captures the main point, which is that disposal of waste through deep-well injection is risky. P2, P3, and P4 are all devoted to describing risks of deep-well injection of hazardous waste.
e
Careful design and ████████ ██ ███████████████████ ██████████ ██ █████████ ███████ ███████████ ████████ ████ ██ ███████████ ███ █████████
This doesn’t capture the author’s focus on the risk posed by deep-well injection of waste. Although the author would probably agree that design and location of injection sites is important, this is too narrow to capture the overall point of the passage.