Midterm #1 Flashcards
What is environmental engineering?
Application of engineering principles to protect and remediate the environment for the benefit of ecosystem and human health
What are typical environmental engineering projects?
Typical EE projects focus on clean water, sanitation, clean energy, pollution remediation, sustainable building, recycling and waste management, and environmental impact assessment
ppm
1 mg / L
ppb
1 ug / L
Risk
The possibility of negative consequences occurring due to exposure to a hazard. Risk = f(hazard, exposure)
Risk assessment components
Hazard identification, toxicity assessment, exposure assessment, risk characterization
Hazard identification
What contaminants exist and are of potential concern?
Toxicity assessment
Dose response; at what level of exposure are adverse effects likely to occur?
Exposure assessment
What are the exposure pathways and and amounts of exposure on those pathways with regard to frequency, duration, and concentration?
Risk characterization
What are the risks for human health and the environment? (Non-carcinogens: HI = sum HQ > 1 indicates a hazard, carcinogens: risk equation)
What is the difference between risk perception and risk assessment?
Risk perception is subjective and not grounded in data, risk assessment is more objective and based on data
K_H
air-water / dissolved gas equilibrium (Henry’s Law) : dissolved oxygen in water, “stripping” of contaminants by conversion to gas form
K_a / K_b
Acid-Base chemistry: adjusting pH to drive reactions towards reactants or products and remove contaminants
K_sp
precipitation-dissolution: removal of hardness from water, precipitation of contaminants by coagulation (heavy metals, organics, URINE CAPTURE)
K_w
also used in acid-base chemistry, equal to 1.0 x 10-14 or [H+][OH-]
