UNIT 4: ENVIRONMENTAL SCIENCE 302

LOCH

Fine SandCoarse SandPebblesBeakerCoffee Filter

How sure are you?

CREATE A KWL CHART

Each student reads the next slide

Can you really flush a fish down the toilet and have it go back to the ocean?How is the water treated?Do you really drink your wastewater?Where does all of the waste go?

What are the types of waste?› Name everything that could be “waste”› Activity at end of class

What are the SOURCES of waste?› Focus on WasteWater

What is the fate of waste?› Focus on WasteWater› Process of WasteWater Treatment

Special Topics

Toilet Sink Washing Machine Dishwasher Your house, a laboratory, an industrial

factory, etc…

PHYSICAL PROCESS

Filtering large particles goes to landfill

Settle large particles on to secondary

removes ~60% of suspended solids from wastewater.

BIOLOGICAL

Bacterial growth promoted, then killed› Aeration encourages bacterial growth

puts O2 back into water

› Bacteria decompose waste – yum!› Bacteria are killed via chlorine (usually)

Removes >90 percent of suspended solids.

CHEMICAL & PHYSICAL

“optional”

Reduce pollutants of “special concern”› Nutrients like Nitrates and Phosphates…why?

Uses coagulating chemicals & a 2nd filter

WATER

Into a lake or river ocean

Crops/Golf course

SLUDGE

Lagoon Incinerator Crop fertilizer

Beauty ProductsMedicine

Engine OilPaint

Lawn Care ProductsPhotographic Chemicals

Used Cooking OilFat from cooking Bacon

DiapersCondoms

http://www.youtube.com/watch?v=Q7bVx8FBx5s&feature=related

Start at 20sec

Wastewater tx plants will always be in the basin of a watershed…why?

Recycles wastewater to drinking water Video clip

Boiling Using Sun’s Rays to

disinfect Lifestraw

Purification plants

How’s this linked to life expectancies? Natural Disasters?

Hiking?

Purification depends on $$$

Grit Filters (to remove large

matter)

Sedimentation tank

Trickling filter

AerationSecondary filters

Wastewater from city

To streamTertiary

treatment

Primary Filters (to remove large matter)

Flocculation tank

Sedimentation tank

Rapid / slow sand filtrationChlorination

Water from rivers / lakes

To tanks in the city

Fill in more items in the “L” column of your KWL

What does it include?› Brainstorm a list of 5 contents

Where does it come from?› Brainstorm a list of 5 contents

Why should humans care?

Why are we concerned about water usage if the law of conservation of matter is true?

Disease-causing pathogens can destroy food chains

Organisms die….leading to low oxygen levels via decomposers› May be due to increased algal growth or more directly

via toxic kills Chlorine compounds and inorganic chloramines

can be toxic to aquatic invertebrates, algae and fish;

Bioaccumulation› Metals, such as mercury, lead, cadmium, chromium

and arsenic can build up a food chain Pharmaceutical and personal care products may

cause unknown effectsunknown effects…

http://ga.water.usgs.gov/edu/wwvisit.html

Stages of treatment, purpose of a treatment plant