#5 - Global Reference, Must Be True

[Administrator]

Complete Question Explanation

The correct answer choice is (C).

Answer choice (A):

Answer choice (B):

Answer choice (C):

Answer choice (D):

Answer choice (E):

This explanation is still in progress. Please post any questions below!

[Lincoln V]

The term "purpose" confused me in regards to C being correct. The correct answer appears to be defining what deep well injections do, not "why" they are performed? Am I wrong in searching for the "why" or am I misinterpreting C?

[Robert Carroll]

Lincoln,

There's really nothing more to the purpose. It's not as if deep-well injection is a natural process. So why did people invent it and why do they do it? To store wastes.

Robert Carroll

[Albertlyu]

Hi PS,

Please, may I ask why C is the right answer here? I think the passage never indicates that containing hazardous waste in salt-saturated water was a "purpose" of injecting the waste.

thank you, PS.

Albert

[nzLSAT]

Yes. I put B for this answer and was wondering if anyone could clarify!

[cleis_]

I like your question about purpose. I wound up able to justify C because I eliminated the four others:

A. "short term" and neutralization were never discussed. This is way out of left field.
B. Obsolescence of the other disposal methods was never discussed. This is said to be a cheaper and more efficient alternative (up to a certain point), but the passage never implies the other methods will no longer be used.
D. The author states in p.3 this is an uncontrolled method of disposal.
E. Recycling is never discussed. Low toxicity is also an issue here - we don't know the toxicity level.

C. Makes the most sense. I can understand the way that you read it OP, because they seem to put the emphasis on the "saltwater saturated underground areas." For me, the key point here is actually "contains hazardous wastes," which is very much in line with the passage and question. Saltwater saturated underground areas is not the "purpose," and I believe it is there to throw us off the scent of the correct answer, but it is consistent with the passage as well.

[Albertlyu]

I like your question about purpose. I wound up able to justify C because I eliminated the four others:

A. "short term" and neutralization were never discussed. This is way out of left field.
B. Obsolescence of the other disposal methods was never discussed. This is said to be a cheaper and more efficient alternative (up to a certain point), but the passage never implies the other methods will no longer be used.
D. The author states in p.3 this is an uncontrolled method of disposal.
E. Recycling is never discussed. Low toxicity is also an issue here - we don't know the toxicity level.

C. Makes the most sense. I can understand the way that you read it OP, because they seem to put the emphasis on the "saltwater saturated underground areas." For me, the key point here is actually "contains hazardous wastes," which is very much in line with the passage and question. Saltwater saturated underground areas is not the "purpose," and I believe it is there to throw us off the scent of the correct answer, but it is consistent with the passage as well.

that makes sense, C is at least consistent with the passage. thank you for your help!

[atierney]

Hello all,

Just to make sure everyone is on the page with this (kind of weirdly worded?) purpose question, here's where I think the passage most directly speaks on the issue:

"In an effort to save time and money, many industries have turned to alternative methods of hazardous-waste disposal, including increased use of deep-well injection. In this method, wells are drilled into porous and permeable rock strata that are already saturated with salt water. Liquid wastes are then injected into the rock strata. Most of these wells are drilled to a depth of at least 300 meters—the minimum depth that generally puts the injected waste at a safe distance below any aquifer, in this case a rock stratum containing drinkable water. Such wells are rarely deeper than 1,800 meters, because below this depth it is more cost-effective to consider an alternative method of disposal. " (emphasis mine).

Based on the above, if we were pre-phrasing this question, we might turn to costs as a main idea, that is to say, the primary purpose is efficiency in hazardous waste disposal. However, such a answer does not appear, and so we have to eliminate obviously wrong answer choice and choose the best viable option. Here, I think you would safely eliminate all but B and C, as these are the only two that really address "hazardous waste." And then as between B and C, C is the safer option, given the idea of making other disposal methods "obsolete." This is a classic "extreme answer choice" that one should always be wary of on the LSAT.

Let me know if anyone has further questions.