Reading ComprehensionDifficulty: Medium

PT158 S1 P1 Q6 ExplanationDeep Well Injection

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TopicsLocate DetailScience

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Passage

A major problem facing industrial societies is their exponentially increasing production of toxic waste. Environmental regulations and expenses for landfills and incinerators have increased significantly in recent years. 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. water. The controversy arises because there are three serious problems with this method of waste disposal.

Under the best conditions, wastes are injected into rock strata saturated with salt water and separated by impermeable rock strata from aquifers containing drinkable water. However, injection wells may leak, allowing significant amounts of noxious chemicals to mix with supplies of drinking water. In other cases, mistakes by personnel working on the dangerous levels of waste materials for long periods of time before the problem is even discovered.

The third problem associated with deep-well injection arises from the fact that it is nearly impossible to predict how the injected wastes will be acted on by the geological features of the injection area. Unlike surface water, the water in underground rock strata does not flow entirely under the influence of gravity. of meters per year through geologic faults, porous rock, or other geologic formations.

The significant uncertainty about where injected wastes will flow, along with the possibilities of mechanical failure and human error, makes deep-well injection a risky means of managing hazardous wastes. Unfortunately, as societies produce more toxic this relatively cheap, efficient means of disposal.

What this question is testing

Locate Detail

Passage Summary

Picture this: toxic waste is expensive to deal with properly, so industries found a cheaper option — just pump it deep underground and hope for the best. The author is here to explain why "hope for the best" is a terrible plan. Wells can leak, humans make mistakes when building them, and underground water is a free spirit that flows wherever pressure gradients push it, including straight toward the aquifer your town drinks from. Despite all this, the practice keeps growing because it is cheap and nobody has come up with a better affordable alternative.

Topic

Why pumping toxic waste underground is a ticking time bomb for drinking water. The author lays out the case that deep-well injection is a gamble we are increasingly losing.

Framework

Problem / Solution gone wrong. The passage sets up a classic "here is a clever workaround" story and then pulls the rug out: the workaround might be worse than the original problem. Think of it as an infomercial that starts with "Tired of expensive waste disposal?" and ends with "Now your drinking water glows in the dark."

Main Point

Deep-well injection sounds like a neat trick — pump the bad stuff far underground and forget about it. But wells leak, humans botch the construction, and underground water wanders wherever it pleases. The author's verdict: this is a risky gamble, and we are doubling down on it because the alternative costs more. The money sentence is in the last paragraph: uncertainty plus mechanical failure plus human error equals a bad time.

P1: Introduction to Deep-Well Injection and Its Controversy

The opening paragraph is the "how we got here" story. Toxic waste is piling up, landfills and incinerators are expensive and drowning in red tape, so industries said "what if we just... put it underground?" The catch: more and more communities drink from those same underground water sources. Controversy ensues. The paragraph ends by promising three problems, which is the author's way of saying "buckle up."

P2: Mechanical Failures and Human Error

Problems one and two arrive together. In a perfect world, waste sits in salty rock behind impermeable barriers and never bothers anyone. In the real world, wells spring leaks and construction crews leave gaps in the casing. One spectacular example: a single gap nearly poisoned the water supply for 100,000 people, and nobody noticed for ages. The takeaway: the system works great until a human touches it.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
6.

According to the passage, deep-well injection of hazardous wastes

Answer choices, explained

  1. Correct79% picked this

    more controversial because of an increased dependence on underground sources of

    Why this is right

    We were looking for a matter of controversy, as growing numbers of communities come to rely on underground sources of drinking water. This answer just opens up its thesaurus and parrots this sentence, using synonyms along the way a matter of controversy = more controversial growing #'s of = increased communities dependence rely on on

    Skill tested: Locate Detail · how this choice captures the passage's function is the move to repeat next time.

  2. Wrong Cause: increased illnesses3% picked this

    more controversial because of an increase in toxin-related illnesses near

    This is what we have to go off of. has become a matter of controversy, as growing numbers of communities come to rely on underground sources of drinking water. The cause of more controversy is identified as the increased reliance on underground water sources, not an increase in toxin-related illnesses.

  3. Opposite16% picked this

    more widely accepted because newly developed alternatives are more expensive than

    We were told it has become controversial, but this says it has become more widely accepted. Our supporting text: has become a matter of controversy, as growing numbers of communities come to rely on underground sources of drinking water.

  4. Opposite1% picked this

    more widely accepted because of increasing public awareness of

    We were told it has become controversial, but this says it has become more widely accepted. Our supporting text: has become a matter of controversy, as growing numbers of communities come to rely on underground sources of drinking water.

  5. Opposite2% picked this

    more widely accepted because of relatively high toxicity of wastes that are disposed of

    We were told it has become controversial, but this says it has become more widely accepted. Our supporting text: has become a matter of controversy, as growing numbers of communities come to rely on underground sources of drinking water.

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