80,000+ tons spilled via broken storm pipe

2008: Tennessee dam break spills 1.1 billion gallons

Kinds of waste

Conventional solid

Conventional liquid

Hazardous waste

Nuclear waste

Agriculture (crops & animals):

more than 50%

Mineral industry

(spoils, tailings, slag, etc)

Cities and towns(small

amount of municipal waste)

Manufacturing (highly toxic)

Major source of solid waste in U.S. are:

The big ones

Important to control

the migration of

leachateSites for sanitary

landfills are often controversial NIMBY issues

Open Dumps – unlovely, unhealthy, and unappetizing

Sanitary Landfills – alternate layers of compacted trash and a

covering material

Barriers lock in toxins and chemicals, reduce leakage into the

environment

Cheap when space is available

Less volume at the end of the waste stream means less landfill

space needed and slower filling of available sites.

Treated organic waste can be fed to swine or composted, or even

converted to energy – onsite or at specialized facilities

Recycling – any reuse of waste reduces volume at landfills

Recover recyclable waste by source separation; separate

waste into useful categories

Twin Cities recycling rate is still

low: 30 – 50% recovery of the

recyclable materials

Saint Paul will see major

changes soon: single

sort, addition of more

types, and curbside composting

are all planned for the near

future

Strategies:

Dilute and disperse

Concentrate and containSecure Landfills – Holding tanks or dams common

Alternative is to place in sealed drums with impermeable lining material

Deep wells – inject deep into the crust

Leachate not contained

Expensive and uncertain

Ajka, Hungary

2010

Aluminum sludge

dam breaks, kills

7; pH = >9

Septic Systems: soil microbes and

oxygen complete the breakdown

of the organic matter

Municipal Sewage Treatment

Primary treatment: removal of

solids from organic liquid waste

bacteria and fungi act to dissolve

and breakdown the organic

matter

filtration, chlorination, and other

chemical treatment may occur

Waste-to-energy alternatives can

Organic solid waste requires treatment

Extra steps to contain and

stabilize hazardous waste

can be expensive

Established by Nuclear Waste Policy Act of

1982 – establish a high-level disposal site

in the west

Characteristics:

Volcanic host rock

Arid climate, low regional water table

Low population density (but Las Vegas is

60 miles to the southeast)

Apparent geologic stability [??]

Enormous and costly legal fight, still no solution but project is near death$ 40,000,000,000

Radioactive Decay – unstable nuclei decay and produce lots of energy – constant rate

Radioisotopes each have their own rate of decay measured in a half-life <1- billions of years

Energetic radioisotopes must be contained out of the environment ‘forever’

BasicsPoint and Non-point Pollution

SourcesOrganic Pollution & EutrophicationAgricultural PollutionIndustrial PollutionGroundwater pollution

All water contains dissolved chemicals – some are natural and some

are produced by a variety of human activity like

agriculture, industry, and residential

All of the chemicals in the environment participate in geochemical cycles of some kind, similar to the hydrologic cycle + rock cycle

Precipitation and rock weathering both contribute

Chemicals transported as dissolved load in stream or ground water

Chemical reactions occur when pollutants come in contact with ecology, sediments, and life

Minerals precipitate out and cycle continues

As pollutants proceed through cycle, they migrate into natural systems

Reservoirs are where these stay for a while –can vary widely over different timescales

Residence Time – how quickly a substance cycles through each of reservoirs - times for different elements vary widely

Humans alter the rate of influx or other parts of this equation

Point source – pollution enters a system from one, identifiable spot.

The point sources are easier to identify as pollution problems

Nonpoint source – pollution enters a system from multiple, more diffuse

sources. We can identify them by using natural geochemical tracers

A major pollution source that eventually biodegrades with shorter residence time

Algae in a pond

Human or animal waste

Runoff from an animal feedlot

Discharge from food processing plants

Runoff from streets or highways

In time organic matter is broken down by bacteria

Eutrophication – complex breakdown of excess organic matter that enriches water with plant nutrients (nitrates, phosphates, and sulfates)

Farmers are using herbicides and pesticides at

all time high rates, exposing animals and

humans to toxic levels of pollution

Fertilizers, when not applied to the land

correctly, build up toxic levels in runoff water

Concentration practices in a small area such as

animal feedlots create problems

Sediment pollution

from farmland

erosion is a major

factor in stream

health

Inorganic Pollutants

Some metals, such as heavy metals = cadmium, lead, mercury, plutonium, and others - accumulate in foodwebs

Hundreds of new chemicals are created

by industrial scientists each year BUT no

toxicity data at all were available for 70%

of them; a complete health hazard

evaluation was possible for only 2%

Nonmetals like acids and alkalines leach out toxic metals -chlorine, cleaning agent / sanitizer, can kill algae and fish

Industrial pollution also includes thermal pollution – excess heatdumping into streams

Migration of polluted ground water by a

pollution plume can result from a point

source

Residence times are important because

recharge water may be discharged from a

well before the residence time has elapsed

Often they are found near landfills, waste

sites, or abandoned tanks

Once in a groundwater system, removal is

difficult and expensive

Hanford pump-and-treat process

25,000,000,000 gallons

TCE = trichloroethylene, an

industrial solvent used at General

Mills research facility

Known for > 30 years about

contaminated groundwater

Proposed copper-nickel mining involves exposure

of sulfide minerals to air, water

MetalSO2 + H2O H2SO4

Pollution could migrate to wetlands, parks, streams

Mining plan

includes

treatment but

timespan could

be 200-500

years!

Barriers can be constructed to isolate polluted sediments - plastic

(impermeable) liners can also isolated toxic water in a system

Addition of nutrients - aluminum, calcium, iron –reduces eutrophication

Dredging removes sediments with toxic compounds - expensive but

likely necessary

Oxygen levels in a lake that is oxygen-depleted

can be restored by aeration

Often the most effective and economical way to

treat polluted ground water is allow natural

processes to remove or destroy pollutants; can

be boosted by addition of beneficial organisms

Decontamination after extraction is the last resort