PT4.S1.Q12 - Leachate Landfill

Number_5

Narrowed down to AC- D, E before settling on D. Hoping to see if theres a good explanation for E and what other tactics work with similar MBT question?

canihazJD

E is just the only one that must be true. If and only if the landfills capacity is exceeded does L escape into the environment. If other words, the only possible way for L to get out is if the capacity is exceeded, AND if the capacity has been exceeded, then L will escape. So if there has been no escape, then capacity has net been exceeded.

D is wrong because we don't know which plants got the L... we only know that most L is sent to plants and some plants can't handle it. It could be that all L that is sent out goes to a plant that can handle it.

McBeck418

I’m just reiterating what was already stated, but hopefully its somewhat helpful.

E is what is backed up by the passage. The passage gives us a bi-conditional if and only if the the landfill exceeds its capacity to hold liquid does it escape.

So, if the liquid escapes, it has exceeded the capacity of the landfill and if the landfill’s capacity is exceeded, the liquid will escape. Therefore, we can accept E because if the liquid is not escaping the landfill, then capacity hasn’t been met.

For D, we know that there are treatment plants and that not all of them can handle the high contamination, but we don’t know that we’ve actively sent sewage to the plants that can’t handle it. We just know those kinds of plants exist. D isn’t provable, so there’s no way to know if it must be true.