Brownfields Flashcards
What is the Risk Assessment?
It is the process of estimating the probability of occurance of an ADVERSE Effect on human and ecological health
resulting from contaminant exposure.
Risk = Probability x Consequence.
Provide an example of this statement
Likelihood vs Consequence.
So if it’s highly likely to have a critical event, then it is a high risk.
If it’s likely to have a marginal (middle) then it would be a medium risk.
Why do we do Risk Assessments?
It helps to provide a consistent, scientific basis to investigate, assess and remediate contaminated sites.
Helps determine the contaminants that post a human/ecological risk.
They prioritize the risk from high to low.
What are the 3 Components of Risk Assessments?
1) Contaminant has to be present at the hazardous concentrations
2) there has to be a receptor
3) an exposure pathway in which the receptor comes in contact with environment or human.
Explain the Contaminant Component of the Risk Assessment
If a chemical concentration is higher than standard levels, then there is a contaminant of concern.
Explain the exposure pathway component
The pathway which allows the receptor to go through and affect other organisms.
Pathway consist of:
1) Air
2) Sediment (materials deposited by water/wind/glaciers)
3) Soil
4) Groundwater
5) Inhalation
6) Dermal (skin penetration)
7) Ingestion
Explain the Receptor Component of Risk Assessment
Receptors could be on humans
- trespassers, woerkers, recreational users, anybody.
Offsite - human receptors that have been exposed to groundwater, air, surface water.
Ecological receptors includes plants, soil, mammal, birds.
Explain an example of a risk assessment.
Metal containments found in the garden soil of a residents home.
The site is the exposure pathway to ingestion of any garden produce.
Example of a Volatile Contaminants
Volatile - evaporative.
Can be present below a home.
The pathway exposure would be the inhalation of indoor air.
What are the Characterization of Risk Assesment?
They characterize the risk assessment by comparing the estimated dose to safe dose.
Then describe the uncertainties in the exposure and toxicity assessments.
Describe the Modelling of Risk Assessment (picture/graphs)
Medium - Route - Receptor
Med::
air water food soil
route::
inhalation, ingestion, dermal
Receptor::
Human/non human
What are the management options for risk contaminants?
Remove, and treat
What are management options for risk receptors?
Relocation, restrict the use of land.
What are some management option for exposure pathways?
Interception, ventilation, containment.
What is BrownFields?
it is a property/expansion/redevelopment/reuse of land that encounter a complication of potential presence of a hazardous substance, pollutant, or containment.
