Reading comp PrepTest 125 · Section 1 · Question 8
Passage
Passage walkthrough
Topic: Science
Passage A
Paragraph 1
- Paragraph note
- Purposes of drilling muds
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- List of many purposes
Paragraph 2
- Paragraph note
- Ingredients of drilling muds
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Bentonite + others
- Largest ingredient - Barite
Paragraph 3
- Paragraph note
- Formulas and problem
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Companies have proprietary formulas
- Problem - Studying impact since formulas are hidden, have different names for ingredients...
Passage B
Paragraph 1
- Paragraph note
- Background and concern
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Background on drilling mud
- Discharge of drilling mud - Main environmental concern
- Regulated and monitored
Paragraph 2
- Paragraph note
- One type of mud - WBM - Safer
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Water-Based Mud (WBM) - Safer, shallow drills, dumped
Paragraph 3
- Paragraph note
- Another type of mud - OBM - Compared to WBM - Regulations
- Views, minor Meta-Structures, points of intersection, and the author's attitude
- Oil-Based Mud (OBM) - Deeper wells, more dangerous
- Compared to WBM - Don’t disperse as readily, more oil, more barite
- Barite can hurt sea creatures
- Regulations on dumping
Main Points:
Passage A - Drilling muds have many purposes, are made up of certain chemicals, and have different formulas for different companies, which has presented problems in studying their effects.
Passage B - The release of WBMs is less harmful to the environment than OBMs, which is reflected in the stricter regulations facing the latter.
Key Lines?Passage A:
- Lines 2-3 - Introduce the purpose of Paragraph 1
- Lines 14-15 - Main ingredient
- Lines 23-26 - A problem is noted
Passage B:
- Lines 33-35 - A problem
- Lines 48-54 - Differences
Meta-Structure? Relationship Between Passages?
This is a weird set of passages in that they’re both largely informative - they don’t really have an argument or a point of view. Rather, we get information about drilling muds in both. There’s some overlap - they both talk about the compositions of drilling muds - but also a lot of information that’s unique to one passage - e.g., Passage A’s discussion of the purpose of drilling muds. Since these passages are largely devoid of viewpoints, we should expect the questions to bring up the details, which means that knowing what information is present in each passage is going to be important.
Problem/Solution - Both passages bring up environmental concerns from the dumping of drilling muds. Passage A talks about the “effects of drilling waste discharges” since they have “sometimes toxic” ingredients (Lines 24-26), and Passage B talks about how OBMs have “a greater potential for negative environmental impact” (Lines 52-53). Neither offers a solution other than regulating these products - these passages aren’t about a solution to it but rather just presenting the information about the drilling muds and the problems they post.
Lists (List of Differences)- Both passages include a list. Passage A lists a bunch of purposes of drilling muds in Paragraph 1; Passage B lists differences between OBMs and WBMs in Paragraph 3.
Last Thoughts?These passages are...boring, for lack of a better word. So it’d be easy to gloss over the information. And there’s also no reason to try to remember all of the key terms, as they’re not things that are familiar to you (bentonite, barite, polymers, etc…). Instead, know what type of information shows up where in each paragraph, and move to the questions as soon as possible so you can spend more time referring back to those details.
Question prompt
Why the credited answer is right
Credited answer: E
The notes below walk through why it fits the stem and how to eliminate the rest.
Question Type
Strategy Overview
Answer Anticipation
Answer choices
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AClay is an important Remaining source text redacted.
Why choice A is not credited
(A) (Lines 12-13; Lines 38-39) This shows up in both passages. We know that both passages discuss the composition of drilling mud, and checking the relevant section in either passage shows us that they both mention clay content.
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BAt least one type Remaining source text redacted.
Why choice B is not credited
(B) (Lines 40-42) Passage B mentions that WBMs are “not particularly toxic to marine organisms,” in contrast to OBMs which can be. Since this answer shows up in Passage B, we can rule it out.
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CThere has been some Remaining source text redacted.
Why choice C is not credited
(C) (Lines 23-24; Lines 52-56) Passage A mentions problems in studying the effects of drilling mud, but that’s not the same as saying studies have been done - it could be that these problems prevent the studies from occurring. However, Passage B brings up information that could only be the result of environmental studies on drilling muds - such as the negative effects on scallops and their slow dispersal. Since this shows up in Passage B, we can eliminate it.
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DGovernment regulations allow drilling Remaining source text redacted.
Why choice D is not credited
(D) (Lines 47-49; Lines 33-35) Passage B talks about the 30% oil content of OBM, and it talks about such mud being allowed by current government regulations earlier in the passage, so we can eliminate this answer. If you got tripped up on the regulation part since it doesn’t explicitly mention it in Paragraph 3 of Passage B, you should have deferred on this answer since it does mention mud with a 30% oil content.
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EDuring the drilling of Remaining source text redacted.
Why choice E matches the stem
(E) (Lines 23-25; Lines 43-46; Lines 56-60) Passage A talks about discharges, but not how they occur, so this isn’t mentioned in Passage A. Passage B says that WBMs are recycled until they no longer work, then dumped over a period of hours - that’s not continuous. And OBMs can only have the residue left after a process is done dumped, which also wouldn’t be a continuous process. This answer shows up in neither passage, so it’s the correct answer.
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Discussion
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Clay? 3 replies
Started by sarahpretzel