Remediation & Mitigation Strategies Flashcards

What is 'thermal desorption' as a soil remediation technology?

Answer: Heating contaminated soil to volatilize organic contaminants for off-gas treatment

Thermal desorption heats excavated or in-situ soil to temperatures that volatilize organic contaminants, which are then captured and treated in a separate off-gas system.

A grounds facility has chronic bare soil areas under dense tree canopy. Which long-term mitigation strategy is most sustainable?

Answer: Applying mulch and establishing shade-tolerant groundcovers

Mulch suppresses weeds and retains moisture while shade-tolerant groundcovers eventually stabilize the area without competing unsuccessfully with tree roots for light.

Which regulatory framework most directly governs the cleanup of contaminated sites in the United States?

Answer: Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA/Superfund)

CERCLA, commonly known as Superfund, authorizes the federal government to respond to releases of hazardous substances and compels responsible parties to clean up contaminated sites.

What is a 'permeable reactive barrier' (PRB) used for in groundwater remediation?

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

A PRB is installed perpendicular to groundwater flow; as contaminated water passes through the reactive medium (e.g., zero-valent iron), contaminants are degraded or immobilized.

Integrated Pest Management (IPM) serves as a mitigation strategy primarily by:

Answer: Reducing pest pressure through combining cultural, biological, and chemical controls to minimize environmental impact

IPM combines multiple tactics in a decision-based framework to manage pests effectively while minimizing pesticide use and environmental risk.

When remediating a fuel oil spill on turf, which bioremediation amendment helps break down petroleum hydrocarbons most effectively?

Answer: Compost with petroleum-degrading microorganisms (bioaugmentation)

Compost amended with petroleum-degrading microorganisms through bioaugmentation introduces specialized bacteria that metabolize hydrocarbon compounds in contaminated soil.

A grounds manager must mitigate nutrient runoff from a heavily fertilized sports field adjacent to a stream. Which practice is MOST effective as a last line of defense?

Answer: Establishing a vegetated riparian buffer strip along the stream bank

A vegetated riparian buffer intercepts surface and subsurface flow, allowing nutrient uptake by plants and sediment filtering before water enters the stream.