CEA Remediation Technologies 2

Question 1

Which remediation technology uses electricity to move contaminants through soil toward electrodes for extraction?

Accepted Answer

Electrokinetic remediation

Answer

Electrokinetic remediation applies a low-level DC current to drive charged contaminants (metals, some organics) through saturated soils toward cathode or anode electrodes for removal.

Question 2

Monitored Natural Attenuation (MNA) relies on which primary naturally occurring processes?

Accepted Answer

Biodegradation, dispersion, dilution, sorption, and volatilization

Answer

MNA depends on a combination of biodegradation, dispersion, dilution, sorption, and volatilization to reduce contaminant mass, toxicity, and mobility without active intervention.

Question 3

In situ chemical reduction (ISCR) using zero-valent iron (ZVI) is most effective for treating which class of contaminants?

Accepted Answer

Chlorinated solvents such as TCE and PCE

Answer

ZVI dehalogenates chlorinated solvents (e.g., TCE, PCE) via reductive dechlorination, converting them to less toxic or non-toxic end products.

Question 4

A permeable reactive barrier (PRB) is best described as:

Accepted Answer

A subsurface wall of reactive material that treats groundwater as it flows through

Answer

A PRB is an in situ passive system placed perpendicular to groundwater flow; reactive media (such as ZVI or activated carbon) treat contaminants as groundwater passes through naturally.

Question 5

Surfactant-enhanced aquifer remediation (SEAR) improves contaminant removal primarily by:

Accepted Answer

Lowering interfacial tension to solubilize or mobilize NAPLs

Answer

Surfactants reduce interfacial tension between NAPLs and water, increasing NAPL solubility and mobility so contaminants can be more effectively flushed and extracted.

(CEA) Certified Environmental Auditor Practice Test

(CEA) Certified Environmental Auditor Practice Test

CEA Remediation Technologies 2