UT Oak Ridge Graduate Program

Geology 490/590

FALL Semester 1996

Class #1 August 27, 1996

Solution to Quiz #1 - September 3, 1996

1. True or False: (6 pts)

Risk Assessments are only performed by highly trained professionals. Laypersons never perform risk assessments in their daily lives.

• Why do you think this statement is true or false?

• Any statement that risk is an integral part of our daily lives would be acceptable.

• Can you give an example?

• Any example, such as daily commute in car, was accepted.
  
  

2. Correct the following diagrams (4 pts)

3. Relate the terms probability, magnitude of effect, risk, dose-response to one another. Use words or equations. (6 pts)

Any combination of text or equations was accepted.
For example, "Risk is a probability value estimate which is derived out of the assessment of the dose-response (or toxicity assessment) for a chemical and out of the assessment of the magnitude of effect (or exposure assessment), which tries to determine the dose a potential receptor may be exposed to."

4. What does CERCLA allow you to do which RCRA doesn’t? (1 pt)

• Describe the concept of the target risk range. (3 pts)

• The target risk range is a range of risk values between 1E-4 and 1E-6. Sites or conditions that cause risk greater than 1E-4 usually need to be addressed further, either through further investigation or remedial action. Risks below 1E-6 are generally considered "de minimis", or more precisely, as levels of risks that usually do not warrant remedial action (cleanup).