Contaminant Subsurface Fate

Question 1

Contaminant Fate is Determined by (3)

Answer 1

1. Retardation
2. Attenuation
3. Mobility Enhancement

Question 2

Retardation

Answer 2

Process that impedes transport of contaminants by removal or immobilization
ex: sorption

Question 3

Attenuation

Answer 3

1. irreversible removal or

2. Transformation

Question 4

Mobility Enhancement

Answer 4

increased subsurface movement

Question 5

Sorption - is reversible!

Answer 5

partitioning of dissolved organic contaminants (solutes) from gw/surface water (solvent) to natural subsurface materials (sorbent)

Question 6

Sorbent

Answer 6

activated carbon

Question 7

Sorbate

Answer 7

the contaminant being removed

Question 8

Driving forces behind sorption (4)

Answer 8

1. Van der Waal Forces
2. Covalent bonds
3. electrical attraction
4. hydrogen bonds

Question 9

ADsorption

Answer 9

chemical partitions ON-TO a surface

Question 10

ABsorption

Answer 10

chemical partitions INTO

Question 11

How does sorption affect retardation?

Answer 11

• Sorption slows the advancement of a plume

- causes retardation

Question 12

How does solubility effect plume (PCE vs. TCM)
PCE = 150 mg/L solubility
TCM=8000 mg/L

Answer 12

TCM plume a lot larger BUT although TCM ~ 50x more soluble than PCE, the plume model is not 50x larger

Question 13

Precipitation

Answer 13

contaminant separates + falls out of solution

• pH dependent
• high pH precipitates metal