Deck 16: Waste Disposal

Question 1

What can escape and contaminate ground or surface waters if the soil below and above a landfill is permeable?

A) Pollutants
B) Contaminants
C) Carcinogens
D) Leachates

Answer 1

D

Question 2

Pollutants escape from improperly designed landfills in all of the following ways except

A) As gases rising through overlying soil.
B) Rodents burrowing into the landfill for shelter.
C) Through uptake in plants growing on the site.
D) Dissolved in leachate infiltrating into soil below.

Answer 2

B

Question 3

Wastes dumped in the oceans at present are mainly

A) Highly toxic industrial wastes.
B) Radioactive wastes, to keep them away from people.
C) Organic wastes.
D) Dredge spoils.

Answer 3

D

Question 4

Organic matter can be beneficial by a process known as

A) Incinerating.
B) Fertilizing.
C) Composting.
D) Harvesting.

Question 5

For a landfill,which of the following techniques provides an incomplete solution to reducing space?

A) Incineration
B) Open dumps
C) Sanitary landfills
D) Ocean dumping

Question 6

If a septic system is to be used for sewage disposal,

A) The surrounding soil must be impermeable to contain the wastes.
B) High population density is required for efficient operation.
C) In normal operation, all potential pollutants will be decomposed.
D) The soil should be unsaturated, containing sufficient air (oxygen) to permit aerobic breakdown of wastes.

Question 7

The problem of solid waste disposal

A) Cannot be reduced because of continuing population growth and the need for replacement of aging buildings.
B) Has been reduced by increasing recovery, recycling and reusing (such as composting, waste exchange programs and reuse of scrap materials).
C) Has been eliminated as of 2002, due to EPA programs and policies.
D) None of the choices are true.

Question 8

Incineration can provide energy as a by-product.Another waste-disposal method that can supply useful fuel is

A) Open dumping with burning.
B) Sanitary landfill.
C) Composting.
D) Deep-well disposal.

Question 9

On-site disposal of food waste using an in-sink garbage-disposal unit is detrimental for all of the following reasons except

A) It reduces the impact on local landfills.
B) It requires electricity and water.
C) It adversely affects the performance of septic systems.
D) It increases the volume of solids that must be treated by municipal wastewater treatment plants.

Question 10

In terms of volume,the largest liquid-waste disposal problem is

A) Sewage.
B) Toxic industrial chemical waste.
C) High-level liquid radioactive waste.
D) Wastewater from mineral-processing activities.

Question 11

In the United States,the major share of municipal soil wastes end up in

A) Incineration facilities.
B) Open dumps.
C) Sanitary landfills.
D) Oceans.

Question 12

The difficulties in recycling where materials are recovered from the municipal refuse requires

A) Source separation.
B) Source assessment.
C) Source provenance.
D) Source assimilation.

Question 13

If one were practicing the dilute-and-disperse approach to disposal of liquid hazardous wastes,one might consider using

A) A conventional sanitary landfill.
B) A deep disposal well.
C) ocean dumping of the wastes.
D) Switching to an alternate, more environmentally responsible approach.

Question 14

In a landfill,

A) The goal is always to keep the wastes as dry as possible.
B) The wastes must be kept saturated to prevent escape of gas.
C) Controlling moisture content can optimize methane production and waste decomposition while minimizing leachate.
D) The wastes must be kept aerated to allow anaerobic decomposition.

Question 15

After aerobic waste decomposition in a landfill has stopped,

A) No further breakdown of wastes occurs.
B) Further leachate is harmless.
C) Anaerobic decomposition produces different gases, including methane.
D) Methane production also ceases in the absence of oxygen.

Question 16

The use of plants in the cleansing of water includes all of the following except

A) Removing oil from ground water.
B) Using wetlands to cleanse surface water before it moves into ecologically sensitive estuaries and tidal flats.
C) Using plant-laden ponds to treat runoff from roads, parking lots and airport runways.
D) Using gravel-filled basins and wetland plants to treat septic-tank effluent, instead of using a conventional drain field.

Question 17

The thickness and __________ of soil are key factors in determining site suitability for a septic system.

A) Mineralogical composition
B) Permeability
C) Porosity
D) Fertility

Question 18

Volumetrically,the two principal sources of solid waste in the United States are wastes from livestock and from

A) Growing crops.
B) Mineral extraction and processing.
C) Municipalities.
D) Industry.

Question 19

Each of the following is true about the recycling of paper except

A) Is facilitated when large quantities of one type of paper are involved.
B) May conflict with other objectives, such as heat production from incineration.
C) The demand on local landfills is increased.
D) Requires source separation of solid wastes.

Question 20

Conventional waste incineration,at moderate temperatures,

A) Is particularly effective for paper and similar flammable materials.
B) Completely destroys toxic organic chemicals.
C) Has the advantage of not producing harmful gases.
D) All of the choices are correct.

Question 21

Disposal of radioactive wastes in clay-rich sediments of the deep sea floor

A) Is presently banned by international treaty.
B) Is not seriously under consideration because of the danger of water pollution.
C) Would provide some containment of radioisotopes even in the event of leakage of wastes from canisters.
D) Would be impractical because of the instability of the sea floor.

Question 22

The disposal rock unit at Yucca Mountain,Nevada is

A) Rhyolitic tuff.
B) Basalt.
C) Granite.
D) Salt.

Question 23

Trash compaction reduces the volume of wastes in a landfill,but also reduces the rate of decomposition of organic matter.

Question 24

All of the following are true statements about the Yucca Mountain Waste Disposal Site except

A) It has been designed for long-term storage of high-level nuclear waste.
B) It is located in a low-permeability, high thermal resistant rock.
C) It is more than 100 miles from a major metropolitan center.
D) It is 200 to 400 meters above the water table and is in a region with an arid climate, so that groundwater pollution potential is minimal.

Question 25

Placement of impermeable materials below a landfill may,in wet climates,lead to excess accumulation of leachate and eventual overflow from the site.

Question 26

Advantages of radioactive-waste disposal in bedded salt deposits include all of the following except

A) The fact that salt will flow plastically and self-seal under pressure.
B) The high melting temperature of salt, which helps contain heat-producing wastes.
C) The abundance of available abandoned salt mines.
D) Salt blocks radiation from radioactive decay.

Question 27

The sludge that is a by-product of municipal sewage treatment

A) Is volumetrically an insignificant problem.
B) Is entirely useless solid waste requiring planned disposal.
C) Is sufficiently purified and harmless that it can safely be dumped anywhere.
D) May be used as fertilizer, provided that it contains sufficiently low concentrations of toxic chemicals.

Question 28

Which of the following statements is not true?

A) Some radioisotopes are also chemical toxins.
B) Except for those living near nuclear plants or uranium mines we are not normally exposed to radiation.
C) Inferences about the effects of low doses of radiation are drawn, in part, by extrapolation from incidents of high dosage.
D) A given radioisotope behaves chemically just like non-radioactive isotopes of the same element.

Question 29

Transuranic wastes are

A) Elements heavier than uranium.
B) Products of uranium fission.
C) Wastes more radioactive than uranium.
D) Wastes that have been treated to make them non-radioactive.

Question 30

Most municipal sewage in the United States is subjected to

A) No treatment at all.
B) Primary (physical) treatment only.
C) Primary and secondary (mainly biological) treatment.
D) Primary, secondary and tertiary treatment, to produce drinking-quality water.

Question 31

If the half-life of carbon-14 is about 5,700 years,then of a given starting quantity,after 22,800 years (four half-lives),what fraction of the original amount will be left?

A) None
B) 1/4
C) 1/8
D) 1/16

Question 32

For the average U.S.resident,the single largest source of radiation exposure is

A) Medical X rays.
B) Operation of nuclear reactors.
C) Radioactive fallout from the atmosphere.
D) Exposure to radon gas.

Question 33

From the point of view of radiation hazard,the radioisotopes of greatest concern are

A) Those of very short half-life (minutes to days).
B) Those of intermediate half-life (years to centuries).
C) Those of very long half-life (millions or billions of years).
D) Inert gases because they escape into the atmosphere.

Question 34

The size of leaching field a septic system requires is determined

A) The height of the water table.
B) Solely on the volume of wastewater that is anticipated.
C) Solely on the permeability of the soil beneath the leach field.
D) Based on both volume of wastewater anticipated and permeability of the soil.

Question 35

In the United States,

A) The Waste Isolation Pilot Plant is receiving government-produced transuranic waste.
B) The Yucca Mountain Waste Disposal Site is receiving high-level nuclear waste.
C) There is almost no nuclear waste material in temporary storage awaiting permanent disposal.
D) None of the choices are correct.

Question 36

All of the following have been proposed as means of disposing of liquid high-level radioactive wastes except

A) A high-temperature incineration to destroy the radioisotopes.
B) Disposal in (under) ice sheets.
C) Disposal in subduction zones.
D) Placement as liquid wastes in bedrock caverns.

Question 37

In developing countries,most sewage is

A) Discharged, untreated, into surface waters.
B) Handled via communal septic tanks.
C) Subjected to primary (physical) but not chemical treatment.
D) Subjected to both primary and secondary sewage treatment.

Question 38

A sanitary landfill is so named because wastes are treated each day to decontaminate them.

Question 39

The two methods of handling toxic liquid wastes include

A) Concentrate and disperse and disperse and dilute.
B) Concentrate and dilute and contain and disperse.
C) Concentrate and disperse and contain and dilute.
D) Concentrate and contain and disperse and dilute.

Question 40

The disposal layer at the Waste Isolation Pilot Plant (WIPP)site is

A) Basalt.
B) Granite.
C) Tuff.
D) Bedded salt.

Question 41

Deep disposal wells for toxic liquid wastes must never extend down to the water table.

Question 42

The time it takes for half the atoms of the isotope to decay is called as the half-life period.

Question 43

Chlorination of some drinking water,if carelessly done,can lead to production of small quantities of toxic chlorinated hydrocarbons.

Question 44

Ocean disposal of dredge spoils may cause water-turbidity problems and release toxic metals into seawater.

Question 45

One concern with respect to expanding "Superfund" through a tax on disposers of toxic wastes is that such a practice might encourage more illicit waste dumping.

Question 46

The classification of radioactive wastes as high-level or low-level is very accurate.

Question 47

The appeal of the Yucca Mountain disposal site is that it is in an area where no earthquakes have occurred for approximately 10,000 years.

Question 48

Consuming products in and recycling of glass is better than consuming products in and recycling aluminum because less energy is needed to re-melt glass bottles compared to that which is needed to re-melt aluminum.

Question 49

Liquid wastes can be incinerated in specially designed equipment,with most toxic organic compounds destroyed in the process.

Question 50

Recycled plastic is mixed with sawdust to make a product known as composite lumber.

Question 51

Steel is in such demand that it is all readily recycled.

Question 52

"Waste exchanges" are international agreements that allow each nation to specialize in certain types of waste disposal with a group of cooperating nations,so each can engage in the types of disposal for which its geology is most suitable.

Question 53

A leaching field is the area around a landfill into which leachate percolates.

Question 54

The Hanford (Washington)Reservation,where high-level liquid radioactive wastes are currently in storage is located near the Columbia River,upstream of Portland,Oregon.

Question 55

Once water has been contaminated with sewage,it is impossible to restore it to drinking-water quality.

Question 56

The basic assumption behind the dilute-and-disperse philosophy of liquid-waste disposal is that even potentially harmful substances pose no threat if sufficiently diluted.

Question 57

Glass bottles or aluminum cans may be recycled into similar new bottles and cans; recycled plastic objects generally can't be remanufactured back into the same objects.

Question 58

Because there is still disagreement about the best methods to use,no high-level radioactive wastes have been consigned to permanent disposal sites,anywhere in the world.