Lecture 20 Flashcards
Give some examples of human caused oil contamination events.
Deepwater horizon disaster -gulf of Mexico- 700M liters
Kalamazoo river - Michigan -3.3M liters
Lac-Megantic (train derailment) - Quebec - 100K L
How can hurricanes lead to petroleum contamination?
Hurricanes, like Katrina and Harvey caused oil manufacturing sites to flood.
What is a local example of oil contamination?
- A creosote plant (a chemical mixture used in wood preservation) leaked chemicals on the South side of the Bow river and those chemicals have now traveled under the river and are affecting water on the North side.
- Gas Plus station, Bowness Rd. 9K Liters leaked from a gasoline storage tank, causing homeowners to be evacuated.
What are the dangers of USTs?
USTs (underground storage tanks)
Threaten drinking water supplies and can affect air quality.
How much oil spills into the ocean each year?
150 million L
This can cause major ecological harm.
What is a superfund?
How many have been established by the US environmental protection agency?
A location polluted by hazardous materials which has been officially recognized by government.
over 1,300 superfunds have been established
In Canada, How many hydrocarbon contaminated sites are currently listed in the Federal Contaminated Sites Inventory
22,000
What are the soil remediation guide lines (in mg/kg) of xylenes, C6-C10, and phenanthrenes?
pg 1
What are the two characteristics of land which determines how clean of hydrocarbons it must be?
- Phase (soil or groundwater)
- Ultimate land use (environmental receptors)
Define Remediation
Any process which removes contaminants
What are three popular physical methods of remediation? What is a limitation of physical methods?
- Incineration
- Landfilling
- Soil Vacuum Extraction (pulls vapors out of soil)
Physical methods can only transfer pollutants from one phase to another.
Define Bioremediation. What is a benefit of it?
- Bioremediation is a remediation strategy that relies on microorganisms to remove or transform contaminants into less harmful compounds.
- Only biological processes can completely destroy harmful contaminants and transform them into innocuous products like CO2 or H2O
What is the comparative cost of bioremediation compared to incineration or soil washing?
pg 1
What is RBCA, and how is it used?
Risk-Based Corrective Action - categorizes sites based off the risks they present such as: environmental impacts, sensitive receptors and possible exposure pathways.
RBCA is used to:
- Identify exposure pathways and receptors
- Determine the urgency at each site
- Determine the level of oversight
- Incorporate risk analysis into all phases or the corrective action process
- Select appropriate and cost-efficient methods of action.
Describe a treatment rain
The bulk of contaminants are removed by physical treatment and then bioremediation is used as a polishing step.
