CHMM Site Remediation 2

Question 1

Which remediation technology uses microorganisms to degrade petroleum hydrocarbons in situ by injecting oxygen or nutrients into the subsurface?

Accepted Answer

Enhanced bioremediation

Answer

Enhanced bioremediation stimulates naturally occurring microorganisms by supplying oxygen, nutrients, or electron donors to accelerate biodegradation of contaminants in situ.

Question 2

Under CERCLA, the National Contingency Plan (NCP) requires that remedies selected for Superfund sites meet what primary standard?

Accepted Answer

Applicable or relevant and appropriate requirements (ARARs)

Answer

NCP requires that Superfund remedies attain ARARs, which are federal and state environmental standards relevant to the site conditions.

Question 3

A site has chlorinated solvent DNAPL contamination. Which technology directly targets the dense non-aqueous phase liquid source zone most effectively?

Accepted Answer

In situ chemical oxidation (ISCO)

Answer

ISCO delivers oxidants such as permanganate, persulfate, or hydrogen peroxide directly into the source zone to chemically destroy DNAPL-phase contaminants.

Question 4

What term describes the process of documenting that a remediated site has achieved cleanup goals and no further action is required?

Accepted Answer

Site closure

Answer

Site closure is the formal regulatory process confirming cleanup objectives have been met, often resulting in a no-further-action (NFA) letter.

Question 5

During a pump-and-treat operation, 'asymptotic tailing' refers to which phenomenon?

Accepted Answer

Contaminant concentrations leveling off at low but persistent levels

Answer

Asymptotic tailing occurs when dissolved contaminant concentrations drop steeply at first but then flatten at persistently low levels due to back-diffusion or NAPL dissolution.

CHMM - Certified Hazardous Materials Manager Practice Test

CHMM - Certified Hazardous Materials Manager Practice Test

CHMM Site Remediation 2