Introduction — pages 1-30 (page number are for the 5th Edition)

1. Be able to list six areas for which environmental engineers are responsible.

(1) Provision of safe, palatable, and ample water public supplies, (2) Proper disposal of or

recycle of wastewater and solid waste (3) Adequate drainage of urban and rural areas for

proper sanitation; (4) The control of water, soil, and atmospheric pollution (5)

Elimination of industrial health hazards (6) Provision of adequate sanitation in urban,

rural, and recreational areas

2. Be able to explain what is meant by environmental ethics.

Environmental ethic: the recognition of the need for adaptation (as means of survival)

Ethos: (Greek for ethic) the character of a person as described by his or her actions

Table of Environmental Code of Ethics

(1) Use knowledge and skill for enhancement and protection of environment, (2)

Hold paramount the health, safety, and welfare of the environment, (3) Perform services

only in areas of personal expertise, (4) Be honest and impartial in serving the public, your

employers, your clients, and the environment, (5) Issue public statements only in an

objective and truthful manner

3. Be able to set up a material balance for an environmental subsystem.

See pg 27-30

Air Pollution (Fundamentals, Standards, Effects and Fate of

Pollutants) — pages 578-623

4. Given appropriate data be able to convert parts per million (ppm) to micrograms

per cubic meter (µg/m3) for an air pollutant and vice versa.

See pg 581-582

5. Given appropriate data be able to apply the material balance approach in

estimating the amount of pollutant that will be released into the atmosphere from a

source material such as sulfur dioxide from the burning of coal.

See lab 1 solutions

6. Be able to explain the influence of environmental factors on the severity of air

pollution effects on materials.

Five mechanisms of deterioration have been attributed to air pollution: abrasion,

deposition and removal, direct chemical attack, indirect chemical attack, and

electrochemical corrosion.

7. Be able to discuss the natural and anthropogenic origin of the seven major

pollutants for which the U.S. Environmental Protection Agency has designated air

quality standards and identify the likely mechanism for their removal from the

atmosphere.

Particulate matter (PM): Natural—dust, pollen, mold; Anthropogenic—mostly stationary

sources such as coal fired powerplants, smelters, furnaces and auto/diesel exhausts;

Removal—multiple methods including magnetic sources, cleaning of fuel (reduction of

ash), electrostatic precipitators

Ozone (O3): Natural—formed when NOx+Hydrocarbons+sunlight react, photochemical

smog; Anthropogenic—aerosol; Removal—Chlorofluorocarbons (CFC) form series of

reactants that remove ozone

Sulfur Oxides (SOx): Natural—found in association of particulates in volcanoes and

oceans, biological decay, acid rain, sedimentation; Anthropogenic—coal burning power

plants, high sulfur oil, diesel fuel; Removal—using low-sulfur fuel, reduction/removal of

sulfur in feed, benefication (reducing sulfur content in fuel and coal)

Nitrogen Oxides (NOx): Natural—precursor to photochemical smog, component of acid

rain, inadvertent pollutant due to high temperature combustion; Anthropogenic—

transportation sources, power plants, industrial sources; Removal—using new low-NOx

burners to reduce emissions, Reburning NOx, Flue gas recirculation and treatment

Lead (Pb): Natural—volcanic activity, airborne soil; Anthropogenic—smelters and

refining processes, incineration of lead-containing wastes; Removal—removal of lead

from gasoline (unleaded), doghouse enclosures that use hoods to collect emissions

Carbon Monoxide (CO): Natural—incomplete oxidation of carbon in natural anaerobic

decomposition of carbonaceous material by microorganisms which releases

approximately 160 teragrams into atmosphere per year; Anthropogenic—motor vehicles,

fossil fuel burning for electricity and heat, industrial processes, solid waste disposal,

miscellaneous burning of leaves, brush, etc.

Volatile Organic Compound/Hydrocarbon (VOC/HC): Natural—oil spills, natural gas,

seeps of mineral hydrocarbons; Anthropogenic—industrial activities such as equipment

leaks, open vats and mixing tanks, storage tanks, unit operations in wastewater treatment

systems, accidental releases; Removal—leak detection repair program, controlling

fugitive emissions, implementing repairs, substituting less volatile compounds, collection

of vapors through air extractors and subsequent treatment of gas stream by removing

vocs with control devices

8. Be able to explain what is meant by “acid rain” and what causes it.

Unpolluted rain is naturally acidic because CO2 from the atmosphere dissolves to a

sufficient extent to form carbonic acid. However, chemical reactions in the atmosphere

convert SO2, NOx, and volatile organic compounds to acidic compounds and associated

oxidants. The concern with acid rain relates to potential effects of acidity on aquatic life,

damage to crops and forests, and damage to building materials.

9. Be able to explain what is meant by “the hole in the ozone layer” and what causes

it.

Chlorofluorocarbons, used as aerosol propellants and refrigerants, react with ozone,

removing ozone from the system, and the chlorine atom is continually recycled to convert

more ozone to oxygen, thus reducing the ozone. There was irrefutable evidence that

CFCs destroy ozone in the stratosphere above Antarctica every spring, thus creating a

“hole”. It was believed this was only for Antarctica, but further studies showed this was

not the case.

10. Be able to explain what is meant by “the greenhouse effect” and what causes it.

Basic Definition: Earth's atmosphere does the same thing as the greenhouse. Gases in the

atmosphere such as carbon dioxide do what the roof of a greenhouse does. During the

day, the Sun shines through the atmosphere. Earth's surface warms up in the sunlight. At

night, Earth's surface cools, releasing the heat back into the air. But some of the heat is

trapped by the greenhouse gases in the atmosphere.

Textbook Explanation: As radiant energy enters our atmosphere, it is affected by aerosols

and atmospheric gases. Some of the constituents scatter the radiation by reflection, some

stop it by adsorption, and some let it pass unchanged. The key phenomenon of interest in

causing the greenhouse effect is the ability of gases to absorb radiant energy. As the

atoms in gas vibrate and rotate, they absorb and radiate energy in specific wavelengths. If

the frequency of the molecular oscillations is close to the frequency of the passing radiant

energy, the molecule can absorb that energy.

Air Pollution (Control Devices) — 647-681

11. Be able to describe briefly the basis for operation for each of the following air

pollution control devices:

a. absorption tower: packed bed, spray tower, wet scrubber; diffusion of pollutant gas to

liquid surface; transfer across gas-liquid interface; diffusion away from interface into

liquid

b. baghouse: uses same principle as vacuum cleaner; cleaned periodically as pressure

drop increases; approx. 2 hours, mechanical rapping, high pressure air jet; dry gas stream;

fire hazard; particulate removal; flue gas desulfurization

c. cyclone separator: good for larger >10 microns particulate removal (wet or dry);

accelerate gas in spiral motion; centrifugal force cause particles to move to outside where

fall down; diameter decrease causes increased efficiency

d. adsorption bed: surface phenomena, physical or chemical bond with adsorbent,

activated carbon, activated alumina, silica gel, one ounce of activated carbon: 5-10 acres,

regenerate/replace bed prior to breakthrough

e. electrostatic precipitator: wire in tube, wire in plate, wetwater spray,

dryrapping, corona wire—imparts electrical charge (negative), particles attracted to

positively charged plates, high particulate removal possible

f. venturi scrubber: velocity of gas is accelerated in throat section by factor of 4, water

spray in throat (atomization of liquid), pressure drop increases intermixing due to

turbulence, separator flowing venture—cyclone

12. Be able to identify the major sources of automotive emissions from the gasoline

engine and briefly explain how they are being controlled.

In typical automobile engine with no air pollution controls, a mixture of fuel and air is

fed into a cylinder and is compressed and ignited by a spark from the spark plug. The

explosive energy of the burning mixture moves the pistons. The pistons’ motion is

transmitted to the crankshaft that drives the car. The burnt, spent mixture passes out the

engine and out through the tail pipe. The ration of air-to-fuel is the single most important

factor in determining emissions from a four-stroke internal combustion engine. For

maximum power, the proportion of air to fuel must be less. When combustion is

incomplete, substantial amounts of material other than carbon dioxide and water are

discharged through the tail pipe. One result of having an inadequate supply of air is the

emission of carbon monoxide instead of carbon dioxide.

Air Pollution (Dispersion of Pollutants) — 623-647

13. Be able to identify the prevailing conditions relating to atmospheric stability

based on the vapor trail from a stack for the six classical types of plume behavior.

14. Be able to explain how terrain influences air pollution problems in an affected

area.

Heat islands: result from a mass of material, either natural or anthropogenic, that absorbs

and reradiates heat at a greater rate than the surrounding area, causing moderate to strong

vertical convection currents above the heat island. Because of the heat island effect,

atmospheric stability will be less over a city than it is over the surrounding countryside.

The good news of this that for ground level sources (automobiles) the bowl of unstable

air that forms will allow a greater air volume for dilution of the pollutants. The bad news

is that under stable conditions, plumes from tall stacks would be carried out over the

countryside without increasing ground level pollutant concentrations, and the instability

caused by the heat island mixes these plumes to the ground level.

Land/Sea Breezes: under stagnating anticyclone, a strong local circulation pattern may

develop across shoreline of large water bodies. During night, land cools more rapidly

than the water. The relatively cooler air over the land flows toward the water. During the

morning the land heats faster than water. The air over the land becomes relatively warm

and begins to rise, and the rising air is replaced by air from over the water body (sea or

lake breeze). The effect of the lake breeze on stability is to impose a surface-based

inversion on the temperature profile. As air moves from water over warm ground, it is

heated from below.

Valleys: when general circulation imposes moderate to strong winds, valleys that are

oriented at an acute angle to the wind direction channel the wind. The valley then

effectively peels off part of the wind and forces it to follow the direction of the valley

floor. Under stagnating anticyclone, the valley will set up its own circulation. Warming

of valley walls will cause the valley air to be warmed, thus becoming more buoyant and

flow up the valley. Then at night, the cooling process will cause the wind to flow down

the valley. Valleys in N-S direction—more susceptible to inversions than level terrain.

Valley walls protect floor from radiative heating by the sun. Yet walls and floor radiate

heat away to the cold night sky.

15. Given appropriate data be able to apply the Gaussian dispersion model in

estimating the 2 ground level concentration of air pollutants released from an

elevated source or the emission rate for a given ground level concentration.

Ask if we will be given what the variables mean with units; ask if we will be given the

graph on pg 635 to determine sy, sz values

16. Be able to explain how a health risk assessment can be used to evaluate a

potential air pollution hazard.

Ask what he means by this

Solid Waste Management — 785-847

17. Be able to characterize the amount of solid wastes produced in the U.S. on a

mass and volume basis.

In 2009, the EPA estimated that the national average rate of solid waste generated was

2.0 kg/capita *day. On this basis, in 2009, the US produced 221 teragrams of solid waste.

This is a 60 percent increase over the 1980 estimate of 137.8 Tg and nearly 175 percent

increase over the 1960 estimate of 80.1 Tg.

18. Be able to define the following terms: garbage, rubbish, refuse, trash.

Garbage: the animal and vegetable waste resulting from the handling, preparation,

cooking, and serving of food.

Rubbish: consists of a variety of both combustible and noncombustible solid wastes from

homes, stores, and institutions, but does not include garbage. It includes paper, cartons,

rags, wood scraps, combustible floor sweepings, etc.

Refuse: consists of rubbish and garbage; also known as solid waste.

Trash: highly combustible waste, paper, wood, cardboard cartons, including up to 10%

treated papers, plastic or rubber scraps; commercial and industrial sources

19. Be able to list the major components of solid wastes and their relative

proportions.

Are you asking for the composition by material in terms of elements or is this the chart

on p790?

Major components of solid wastes:

20. Be able to list and describe the four means of solid waste management.

Decisions in solid waste management policy formulation must be made in four basic

areas: collection, transport, processing, and disposal.

Collection: both point of collection and frequency of collection should be evaluated in

terms of their impact on collection costs. Increases in productivity of collection personnel

can dramatically reduce overall costs.

Transport: the distance between the disposal site and the center of the city will determine

the advisability of including a transfer station in the transport system. In addition to

distance traveled to the disposal site, the time required for the transport is a key factor,

especially in traffic-congested large cities. The tradeoffs involved in transfer station

operations are the capital and operating costs of the transfer station as compared to the

cost (mostly labor) of having route collection vehicles travel excessive distances to

disposal site.

Processing: In processing prior to land disposal, the primary objective is to reduce the

volume of wastes

21. Given appropriate data be able to determine the dry weight of solid waste

components.

6. Be able to explain what a transfer station is and what purpose it serves.

A transfer station is a place where trucks dump their loads into a larger vehicle where it is

compacted. By combining loads, the cost per Mg*km for transport to the landfill is

reduced. The tradeoffs involved in transfer station operations are the capital and

operating costs of the transfer station as compared to the cost (mostly labor) of having

route collection vehicles travel excessive distances to the disposal site. These tradeoffs

can be computed to find the point at which transfer becomes economically advantageous.

22. Be able to list the site selection criteria for a sanitary landfill.

Should I use list on page 812 or list online?

23. Be able to define the following terms and describe how they relate to a sanitary

landfill:

Liner: according to EPA rules, new landfills must be lined in a specific manner or meet

maximum contaminant levels for the groundwater at the landfill boundary

Daily cover: the main function of the final (daily) cover is to prevent moisture from

entering the finished landfill; if no moisture enters, then at some point in time the

leachate production will reach minimal proportions and the chance of groundwater

contamination will be minimized

Cell: where the trash is stored within the landfill

Leachate: liquid that passes through the landfill and that has extracted dissolved and

suspended matter from it

Leachate collection system: designed by sloping the floor of the landfill to a grid of

underdrain pipes that are placed above the geomembrane (synthetic membrane liner)

Cap: seals off the top of the landfill from water to prevent leachate formation

Gas vents: installed in a landfill to promote stabilization of landfilled waste; passive gas

vents can be used to aerate landfilled waste as well as collect and release landfill gas

24. Be able to draw a diagram of a typical sanitary landfill showing how it is

constructed.

See page 826

25. Given appropriate data be able to calculate how long it would take leachate to

migrate through a clay liner.

Historically, landfill liners were constructed with only a single clay liner. Over time the

leachate will pass through the liner. This is called a break throught. The following

equation is used to estimate the time to breakthrough:

t = [(T^2) n] / K (H+T) where t = breakthrough time (y), T = thickness of clay

liner (m), n = clay liner porosity, K = hydraulic conductivity (m/y), H = depth of leachate

above liner (m)

Ask if we have to use his method from lecture or if we can use method on p831

Hazardous Waste Management — 866-935

26. Be able to list the five categories that are used in classifying hazardous wastes.

(1) Specific types of wastes from nonspecific sources (2) Specific types of wastes from specific sources (3) Any commercial chemical product or intermediate, off-specification product, or residue that has been identified as an acute hazardous waste (4) Any commercial chemical product or intermediate, off-specification product, or residue that has been identified as hazardous waste (5) Characteristic wastes27. Be able to list and describe the four categories of “characteristic wastes”.

Ignitability—Ignitable wastes can create fires under certain conditions, are spontaneously

combustible, or have a flash point less than 60C

Corrosivity: Corrosive wastes are acids or bases (pH less than or equal to 2, or greater

than or equal to 12.5) that are capable of corroding metal containers, such as storage

tanks, drums, and barrels.

Reactivity: Reactive wastes are unstable under “normal” conditions. They can cause

explosions, toxic fumes, gases, or vapors when heated, compressed, or mixed with water.

Toxicity: Toxic wastes are harmful or fatal when ingested or absorbed. When they are

land disposed, contaminated liquid may leach from the waste and pollute ground water.

28. Be able to sketch the general structure of dioxins and PCBs and explain why

each is hazardous.

Dioxins and polychlorinated biphenyls (PCBs) are toxic chemicals that persist in the

environment and accumulate in the food chain. Dioxins have no technological or other

use, but are generated in a number of thermal and industrial processes as unwanted and

often unavoidable by-products. In contrast to dioxins, PCBs had widespread use in

numerous industrial applications, and were produced in large quantities for several

decades with an estimated total world production of 1.2-1.5 million tonnes, until they

were banned in most countries by the 1980s.

Dioxins and PCBs are found at low levels in many foods. Longer-term exposure to these

substances has been shown to cause a range of adverse effects on the nervous, immune

and endocrine systems, and impair reproductive function. They may also cause cancer.

Their persistence and the fact that they accumulate in the food chain, notably in animal

fat, therefore continues to cause some safety concerns.

29. Be able to define the cradle to grave concept and how it relates to the “manifest”.

Cradle to grave concept: an attempt to track hazardous waste from its generation point

(the “cradle”) to its ultimate disposal point (the “grave). The system requires generators

to attach a manifest (itemized list describing the contents) form to their hazardous waste

shipments. This procedure is designed to ensure that wastes are directed to, and actually

reach, a permitted disposal site

30. Be able to define RCRA, HSWA, CERCLA, SARA, TSD, and “four nines”.

RCRA: Resource Conservation and Recovery Act—directed EPA to establish hazardous

waste regulations

HSWA: Hazardous and Solid Waste Amendments—amended RCRA to regulate the

generation and disposal of hazardous wastes

CERCLA: Comprehensive Environmental Response Compensation and Liability Act—

also called “Superfund”, enacted to address abandoned or closed waste disposal sites or

spills

SARA: Superfund Amendments and Reauthorization Act—in this, Congress expressed a

preference, but not a requirement, for remedies such as incineration or chemical treatment

that render a waste nonhazardous rather than transport to another disposal site or simple

containment on site. SARA directs that the level of cleanup should achieve compliance

with Applicable or Relevant and Appropriate Requirements

TSD: Treatment, Storage, and Disposal Requirements—in this, all TSDs handling

hazardous waste must obtain an operating permit and abide by the treatment, storage, and

disposal regulations. The TSD regulations establish performance standards that owners

and operators must apply to minimize the release of hazardous waste into the

environment

“Four Nines”: Hazardous waste incinerators (waste material burners) must be designed to

achieve a 99.99 percent destruction and removal efficiency (DRE) of the principal

organic hazardous components (POHCs) in the waste.

31. Be able to list six disposal technologies for hazardous wastes.

I cannot find this in the textbook or notes.

32. Be able to describe the various phases in the “permitting process” for a

hazardous waste incinerator and how a “trial burn” is incorporated into the

process.

Hazardous waste incinerators require multiple permits, including a federal RCRA permit.

As part of the RCRA permit application, a trial burn plan detailing waste analysis, an

engineering description of the incinerator, sampling and monitoring procedures, test

schedule and protocol, as well as control information, must be developed. If the EPA

determines that the design is adequate, a temporary or draft permit is issued. This allows

the owner or operator to build the incinerator and initiate the trial burn procedure. The

temporary permit covers the four phases of operation:

1st phase: immediately following construction, the unit is operated for shake-down

purposes to identify possible mechanical deficiencies and to ensure its readiness for the

trial burn procedures.

2nd phase: the trial burn is conducted. This is the most critical component of the

permitting process because it demonstrates the incinerator’s ability to meet the three

performance standards. In addition, performance data collected during the trial burn

phase are reviewed by the permitting official and become the basis for setting the

conditions of the facility permit.

3rd phase: consists of completing the trial burn and submitting the results. This

lasts several weeks to months, during which the incinerator is allowed to operate under

specified conditions. Data is then reported to regulatory agencies.

4th phase: provided that performance standards are met in the trial burn, the fourth

phase is conducted which continues through the duration of the permit. In the event that

the trial burn results do not demonstrate compliance with standards, the temporary permit

must be modified to allow for a second trial burn.