Download - What is Risk?
What is Risk?
Stella SwansonGolder Associates Ltd.
Betty HutchinsonNorthern Mines Monitoring Secretariat
Ecological Risk Assessment Workshop June 2005
Risk is an Everyday Thing
Planning a Boat Trip
Goal: Make Sure the Boat Stays Afloat
Is It Safe?
Standards:
• The rating of the motor
• How many people can the boat hold?
Is It Safe?Variables:• Weather
• Distances to be travelled
• Experience of the boat operator
• Condition of the boat and motor
• The navigation aids and equipment – e.g. maps
How Sure Are We?
Add to Our Confidence That it is Safe By:• Having enough approved life vests
• Having a first aid kit and bailing equipment
• Having fishing gear along in case have to get emergency food
• Checking the fuel – and having extra fuel along
• Tool kit for motor repairs
• Filing a travel plan
Is this Reasonable?How much risk
are we willing to take?
• Can we really count on the weather and are we prepared if the weather gets bad?
• Is there really room for one more moose?
Assessment of Risksfrom Chemicals
Goal: Make sure fish continue to be present in normal numbers and in a healthy state
Is it Safe?“Standards”:• Water quality guidelines or
objectives• Sediment quality guidelines• Consumption guidelines for
concentration of chemicals in fish
• Benchmarks –the level of chemical where we are confident that the fish are protected at the population level
Benchmark
Guideline
Effluent Discharge Point
100 mDownstream
500 mDownstream
Is it Safe?“Variables:”• Amount of chemical being
released after treatment in the effluent treatment system
• Size of the creek, river or lake that the chemical is entering
• Amount of the creek or lake that has changes in chemical concentrations
Is it Safe?Variables, Cont’d• The kinds of fish present in the
creek, river or lake and how sensitive they are to the chemicals
• Whether the fish use the area right where the chemical enters the creek, river or lake for things such as spawning or over-wintering
• Whether the chemical is in a form that can enter the body of the fish
How Sure Are We?Chemical• Treat the effluent to the
best of our ability in order to get chemical concentrations down as low as practical
• Apply safety factors to the water quality or sediment quality objectives or to the effects benchmarks for fish
Boat Trip• Use life vests and
have bailing buckets in the boat
• Boat maximum capacity and motor rating include safety factors
How Sure Are We?Chemical• Deliberately over-estimate the
amount of time fish spend in the area right where the effluent enters the river or lake
• Monitor the water, sediments and fish to be sure that our assessment is correct
• Go back and correct if monitoring shows assessment has some errors
Boat Trip• Look at worst case
weather scenarios
• Keep an eye on weather and performance of the motor
• Leave half of the moose behind if over-loading the boat
Is that Reasonable?
• how important is it to protect fish?
• is the level of safety for the fish correct given how important the fish are?
Is that Reasonable?Chemicals• Different people will
have different opinions as to acceptable risk
• Basic principle for fish: fish continue to be there in normal numbers and in a healthy state
Boat Trip• There may be differences in
opinion re loading the boat with the moose even if somewhat overloaded
• Basic principle: correct balance between benefit of bringing back the whole moose and the risk of swamping the boat