Env Rem Student generated final review

Phytosequestration

Plant roots trap toxins in the soil.

Rhizodegradation

Microbes near roots break down toxins.

Phytohydraulics

Plant roots act as a water pump.

Phytoextraction

Plants pulls metals up into its body

Phytodegradation

Plant enzymes digest toxins internally.

Phytovolatilization

Plants turns toxins to vapor and release them into the air.

What is the primary goal of In Situ Solidification (ISS)?

To encapsulate the contaminant in a solid mass without changing its chemical nature.

Which technology uses reagents to promote the chemical transformation?

In Situ Stabilization (IST)

According to the van’t Hoff equation, Gibbs free energy is defined as

change in gibbs free energy = change in enthalpy - (temp x entropy)

What type of reaction is characterized by an increase in Gibbs free energy and consumes energy?

Endergonic reactions

True or False: Exergonic reactions may occur spontaneously.

True

In thermodynamics, what does a negative value for the change in enthalpy (ΔH) indicate?

The reaction is exothermic and generates heat.

Enthalpy

The quantity of heat absorbed/released by a system at constant temperature and pressure.

Volatility

A measure of how easily a substance turns to gas

In the process of metal precipitation, what is the first step where a phase change occurs?

Nucleus formation

What defines ‘Continuous PRB” as opposed to a “Gate” system?

The reactive or cleaning material covers the entire width of the spill to block any movement around it.

What is the primary drawback to phytoremediation compared to excavation?

It works extremely slowly and is limited by plant root depth

Biostimulation

Adding nutrients or electron acceptors to stimulate existing indigeous microbes

Why is the ‘lag time’ a consideration in bioremediation?

It is the period required for microbes to acclimate to and begin degrading contaminants.

Electrical Resistance Heating (ERH)

Using electrodes to heat soil and promote volatilization.

In chemical remediation, which field determines if a reaction has a plausible rate of occurrence?

Kinetics

What is a mjaor benefit of ‘Dig and Haul’ (excavation) for remediation?

it is very fast and completely removes the source from the site.

Zero-order reaction

A reaction appears to be a straight line sloping downward on a concentration-time chart.

Provide an example of a ‘forever chemical’ often found in waterproof coatings.

PFAS (Per- and Polyfluoroalkyl Substances)

Which emerging contaminant is often found in sunscreen and plastics?

Microplastics and certain chemical UV filters (CECs).

What is the “RCRA 8” metal often found in pressure-treated wood and mining waste?

Arsenic

What does ZVI stand for in the context of permeable reactive barriers?

Zero Valent Iron

A ____ PRB uses ‘wings’ to direct groundwater toward a specific treatment area.

Funnel and Gate

List 3 metals that would count as “E-waste.”

They include lead, copper, chromium, nickel, zinc, cadmium, and mercury.

Arsenic

The specific RCRA 8 metal often found in pressure-treated wood and mining waste.

Heavy Metals

They can’t be destroyed, only moved or trapped, unlike organic pollutants.

Nucleaus, Crystallite, and Crystal formation

The 3 steps of precipitate formation for metals in a matrix.

What zone does Soil Vapor Extraction (SVE) target?

The Vadose Zone (the unsaturated zone).

Secondary Maximum Contaminant Levels (SMCLs)

They address aesthetics like taste, odor, and color.

What quality makes a contaminant an ideal candidate for SVE?

High vapor pressure.