CEA Soil Contamination Assessment 5

Question 1

Which in-situ soil remediation technology works by injecting steam or hot water into the subsurface to volatilize and remove contaminants?

Accepted Answer

In-situ thermal treatment (ISTT)

Answer

In-situ thermal treatment (ISTT) uses steam injection, electrical resistance heating, or conductive heating to raise subsurface temperatures and volatilize contaminants for extraction.

Question 2

What is the significance of the 'total threshold limit concentration' (TTLC) in California's soil contamination regulations?

Accepted Answer

It is the state-specific total concentration threshold above which a soil is classified as hazardous waste

Answer

California's TTLC is a total concentration threshold; soils exceeding TTLC for listed constituents are classified as hazardous waste under California law.

Question 3

A brownfield redevelopment project proposes to convert an industrial site to a daycare facility. How does this change in land use affect soil cleanup standards?

Accepted Answer

It requires more stringent cleanup standards due to the sensitive receptor population and residential-equivalent exposure assumptions

Answer

Sensitive receptors such as children at a daycare facility trigger more stringent, residential-type cleanup standards due to higher exposure frequencies, lower body weights, and greater susceptibility.

Question 4

Which document does EPA require to be completed before initiating a time-critical removal action at a contaminated soil site?

Accepted Answer

Action Memorandum

Answer

An Action Memorandum documents the basis for and scope of a time-critical removal action and must be approved before cleanup activities begin under CERCLA.

Question 5

What is 'phytoremediation' and for which soil contaminants is it generally MOST effective?

Accepted Answer

Use of plants to accumulate, degrade, or stabilize contaminants; most effective for metals and some organic compounds in shallow soils

Answer

Phytoremediation uses plants to hyperaccumulate metals or promote rhizosphere biodegradation of organics; it is best suited for shallow, diffuse contamination with metals such as lead, arsenic, or cadmium.

(CEA) Certified Environmental Auditor Practice Test

(CEA) Certified Environmental Auditor Practice Test

CEA Soil Contamination Assessment 5