Remediation

Question 1

PRG DEF

Answer 1

conc below which risk level acceptable

Question 2

MCLG DEF

Answer 2

Residual water must meet before remediation complete under SDWA. Max level of no known adverse health effects. Non-enforceable

Question 3

Def - CSM

Answer 3

Organise and communicate info on site characteristics (inc receptors), Conceptual site model

Question 4

Thermal treatment (aka thermal desorption)

Answer 4

Soil placed in rotary kiln, heated to 1,100 oF. Volatilized contaminants, mixed with natural gas & incinerated in an afterburner. Can produce recyclable by-product soils. Efficiency up to 99%. Lower efficiencies for high water content, semi-volatile, and fine grained soils.

Question 5

Asphalt Incorporation

Answer 5

Alt to thermal treatment. Lighter molecular weight (Lower volatility) chemicals volatilize while binders in the asphalt stabilize remaining contaminants.

Question 6

Soil Stabilization

Answer 6

METALS and NON-VOLATILES. Soil mixed with stabilizing agents. If these are fly ash or cement process is termed pozzolanic encapsulation. Binds contaminants, reducing leaching potential.

Question 7

Soil Vapor Extraction - pros and cons

Answer 7

Popular for volatiles. Done in Situ. Light NAPL. Stimulates aerobic biodegradation. explosive atm. NOT multicyclic compounds.

Question 8

Phytoremediation

Answer 8

radiation, BTEX, TCE, multicyclic compounds, heavy metals. Longer term. cold and dry slows.

Question 9

Thermal treatment not suitable for

Answer 9

Clorinated hyrocarbons as these may produce HCl(g) and undesirable byproducts. Which requires acid scrubbers, increases cost and complicates air permitting

Question 10

Air Stripping

Answer 10

Most effecient and cost-effective. Semi-volatile organic compounds and metals -
liquid-phase carbon adsorption.
For high-capacity systems that recover
semi-volatile or non-volatile organics, biological treatment systems NUFF CHAT

Question 11

Air Sparging

Answer 11

Injection wells introduce air via a compressor into wells that removes contaminants via “air stripping”, enhanced biodegradation or both. Requires “soil vapor extraction” for air rising from the wells. Generally uses vertical injection wells.

Question 12

Oxidation things

Answer 12

Using strong electron accepting chems such as iron to recover PERC along interceptor trenches. Fentin reagent chemistry also used

Question 13

Low profile tray-air strippers - benefits

Answer 13

More efficient and less maintenancy than packed tower air strippers.

Question 14

Air sparging vs. groundwater recovery

Answer 14

better mass recovery and lower maintenancy but no hydraulic control.

Question 15

fentin reagent chemistry

Answer 15

Uses H2O2 and Ferrous Ion (usually a ferrous sulfate?)