Biodegradability & the 4R’s

- What does biodegradable mean?- What are two universal sheets that identify risks associated

with hazardous materials? - What is one pro and one con for CFC’s?- What is one way that stops toxic chemicals from being released into the air?- What is one way that stops toxic chemicals from being released into water?

N.I.M.B.Y

• NOT IN MY BACKYARD!

Biodegradable

• Substance can be broken down by bacteria, fungi, and other simple organisms.

https://www.youtube.com/watch?v=c0En-_BVbGc

Should you be throwing that away?

•Cotton fabric- 1-5 months

•Paper: 2-5 months

•Cigarette butts: 1-12 years

•Milk cartons: 5 years

•Leather: 25-40 years

•Aluminum cans: 80- 100 years

•Plastic 6-pack holder rings: 450 + years

•Disposable diapers: 550 years

•Glass bottles: 1 million yearshttps://www.youtube.com/watch?v=CzkgaUjIueY

Hazardous wastes

• Any discarded material that contains substances that are:– Poisonous– Toxic– Corrosive– Flammable– Explosive

4 R’s https://www.youtube.com/watch?v=Y68tBxVrnXg(1min-2:30)

Hazardous wastes in our air: CFC’s

• Chlorofluorocarbons (CFC’s): a chemical that consists of chlorine, fluorine and carbon.

CFC’s: What were they used for?

• air conditioning units, refrigerators, Styrofoam, and aerosol cans

Cons of CFC’s?

• They rise to the ozone layer

• Break down when exposed to the sun’s radiation. Then, the atomic chlorine breaks down ozone – O3.

Atomic chlorine• 1973: Learned it was a catalyst for ozone

destruction

• 1 chlorine atom can destroy morethan 100 000 ozone molecules

Domino effect…

• Decreased ozone = increased UV rays

• More incidents of skin cancer.

• Warming of environments

Restrictions weren’t necessarily all good

•Health Canada banned the use of CFC’s in inhalers in 2009, but the replacement HFA (hydrofluoroalkane) weren’t as good at delivering medicine

•Positives: They’re better at

delivering inhaler medication.

Water treatment plant:

https://www.youtube.com/watch?v=pC1u6rJkyzA

• What happens during Primary Water Treatment:

• During Secondary Treatment, oxygen is bubbled through the water in order to increase the break up of organic matter. How does bubbling oxygen through the water help?

• As the organic matter is broken down, it sinks to the bottom of the tank and is known as sludge. What happens to the sludge and what can it be used for?

• What is done to the remaining liquid to further treat it?

Tertiary treatment gets rid of phosphates and nitrates. How does it do this? Why does it do this?

Landfill construction and design

What is a sanitary landfill site?

What is the purpose of incorporating a clay or plastic lining on the bottom of a landfill site?

How do we handle the liquid waste?

• Leachate: liquid that results as wastes decompose