Resources management

1. University College of Science, OU
Resources Management
Haroon Hairan
8/14/2014

2. Unit-I
Population Stabilization
The Commission’s Perspective
Soon after the Commission’s first meeting in June 1970, it became evident that the
question of population stabilization would be a principal issue in its deliberations. A
population has stabilized when the number of births has come into balance with the
number of deaths, with the result that, the effects of immigration aside, the size of the
population remains relatively constant. We recognize that stabilization will only be
possible on an average over a period of time, as the annual numbers of births and deaths
fluctuate. The Commission further recognizes that to attain a stabilized population would
take a number of decades, primarily because such a high proportion of our population
today is now entering the ages of marriage and reproduction.
As our work proceeded and we received the results of studies comparing the likely
effects of continued growth with the effects of stabilization, it became increasingly
evident that no substantial benefits would result from continued growth of the nation’s
population. This is one of the basic conclusions we have drawn from our inquiry. From
the accumulated evidence, we further concluded that the stabilization of our population
would contribute significantly to the nation’s ability to solve its problems. It was evident
that moving toward stabilization would provide an opportunity to devote resources to
problems and needs relating to the quality of life rather than its quantity. Stabilization
would “buy time” by slowing the pace at which growth-related problems accumulate and
enhancing opportunities for the orderly and democratic working out of solutions.
The Commission recognizes that the demographic implications of most of our
recommended policies concerning childbearing are quite consistent with a goal of
population stabilization. In this sense, achievement of population stabilization would be
primarily the result of measures aimed at creating conditions in which individuals,
regardless of sex, age, or minority status, can exercise genuine free choice. This means
that we must strive to eliminate those social barriers, laws, and cultural pressures that
interfere with the exercise of free choice and that governmental programs in the future
must be sensitized to demographic effects. *
Recognizing that our population cannot grow indefinitely, and appreciating the
advantages of moving now toward the stabilization of population, the Commission
recommends that the nation welcome and plan for a stabilized population.
There remain a number of questions which must be answered as the nation follows a
course toward population stabilization. How can stabilization be reached? Is there any
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3. particular size at which the population should level off, and when should that occur?
What “costs” would be imposed by the various paths to stabilization, and what costs are
worth paying?
Criteria for Paths to Stabilization
An important group in our society, composed predominantly of young people, has been
much concerned about population growth in recent years. Their concern emerged quite
rapidly as the mounting pollution problem received widespread attention, and their goal
became “zero population growth.” By this, they meant in fact stabilization—bringing
births into balance with deaths. To attain their objective, they called for the 2-child
family. They recognize, of course, that many people do not marry and that some who do
marry either are not able to have or do not want to have children, permitting wide
latitude in family size and attainment of the 2-child average.
Some called for zero growth immediately. But this would not be possible without
considerable disruption to society. While there are a variety of paths to ultimate
stabilization, none of the feasible paths would reach it immediately. Our past rapid
growth has given us so many young couples that, even if they merely replaced
themselves, the number of births would still rise for several years before leveling off. To
produce the number of births consistent with immediate zero growth, they would have
to limit their childbearing to an average of only about one child. In a few years, there
would be only half as many children as there are now. This would have disruptive effects
on the school system and subsequently on the number of persons entering the labor
force. Thereafter, a constant total population could be maintained only if this small
generation in turn had two children and their grandchildren had nearly three children on
the average. And then the process would again have to reverse, so that the overall effect
for many years would be that of an accordion-like continuous expansion and
contraction.’
From considerations such as this, we can begin to develop criteria for paths toward
population stabilization. It is highly desirable to avoid another baby boom.
Births, which averaged 3.0 million annually in the early 1920’s, fell to a 2.4 million
average in the 1930’s, rose to a 4.2 million average in the late 1950’s and early 1960’s,
and fell to 3.6 million in 1971.3 These boom and bust cycles have caused disruption in
elementary and high schools and subsequently in the colleges and in the labor market.
And the damage to the long-run career aspirations of the baby-boom generation is only
beginning to be felt.
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4. The assimilation of the baby-boom generation has been called “population peristalsis,”
comparing it to the process in which a python digests a pig. As it moves along the
digestive tract, the pig makes a big bulge in the python. While the imagery suggests the
appearance of the baby-boom generation as it moves up the age scale and through the
phases of the life cycle, there is reason to believe that the python has an easier time with
the pig than our nation is having providing training, jobs, and opportunity for the
generation of the baby boom.
Thus, we would prefer that the path to stabilization involve a minimum of fluctuations
from period to period in the number of births. For the near future, these considerations
recommend a course toward population stabilization which would reduce the echo
expected from the baby-boom generation as it moves through the childbearing ages and
bears children of its own.
Our evidence also indicates that it would be preferable for the population to stabilize at a
lower rather than a higher level, Our population will continue to grow for decades more
before stabilizing, even if those now entering the ages of reproduction merely replace
themselves. The population will grow as the very large groups now eight to 25 years of
age—the products of the postwar baby boom—grow older and succeed their less
numerous predecessors. How much growth there will be depends on the oncoming
generations of young parents.
Some moderate changes in patterns of marriage and childbearing are necessary for any
move toward stabilization. There are obvious advantages to a path which minimizes the
change required and provides a reasonable amount of time for such change to occur.
Population stabilization under modern conditions of mortality means that, on the
average, each pair of adults will give birth to two children. This average can be achieved
in many ways. For example, it can be achieved by varying combinations of nonmarriage
or childlessness coexisting in a population with substantial percentages of couples who
have more than two children. On several grounds, it is desirable that stabilization
develop in a way which encourages variety and choice rather than uniformity.
We prefer, then, a course toward population stabilization which minimizes fluctuations
in the number of births; minimizes further growth of population; minimizes the change
required in reproductive habits and provides adequate time for such changes to be
adopted; and maximizes variety and choice in life styles, while minimizing pressures for
conformity.
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5. An Illustration of an Optimal Path
Our research indicates that there are some paths to stabilization that are clearly
preferable. These offer less additional population growth, involve negligible fluctuations
in births, provide for a wide range of family sizes within the population, and exact
moderate “costs”—that is, changes in marriage and childbearing habits, which are in the
same direction as current trends.
A course such as the following satisfies these criteria quite well.4
(The calculations
exclude immigration; the demographic role of immigration is reviewed in the next
chapter.)
In this illustration, childbearing would decline to a replacement level in 20 years. This
would result if: (1) the proportion of women becoming mothers declined from 88 to 80
percent; (2) the proportion of parents with three or more children declined from 50 to
41 percent; and (3) the proportion of parents with one or two children rose from 50 to
59 percent. Also in this illustration, the average age of mothers when their first child is
born would rise by two years, and the average interval between births would rise by less
than six months. The results of these changes would be that the United States population
would gradually grow until it stabilizes, in approximately 50 years, at a level of 278
million (plus the contribution from the net inflow of immigrants). Periodic fluctuations in
the number of births would be negligible.
The size of the population in the year 2000 will depend both on how fast future births
occur as well as on the ultimate number of children people have over a lifetime. Over the
next 10 to 15 years especially, we must expect a large number of births from the
increasing numbers of potential parents, unless these young people offset the effect of
their numbers by waiting somewhat before having their children. Postponement and
stretching-out of childbearing, accompanied by a gradual decline in the number of
children that people have over a lifetime, can effectively reduce the growth we shall
otherwise experience.
Beyond this, there are persuasive health and personal reasons for encouraging
postponement of childbearing and better spacing of births. Infants of teenage mothers
are subject to higher risks of premature birth, infant death, and lifetime physical and
mental disability than children of mothers in their twenties.5
If the 17 percent of all
births occurring to teenage mothers were postponed to later ages, we would see a
distinct improvement in the survival, health, and ability of these children.
It is obvious that the population cannot be fine-tuned to conform to any specific path.
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6. The changes might occur sooner or later than in this illustration. If they took place over
30 years instead of 20 we should expect nine million more people in the ultimate
stabilized population—or 287 million rather than 278 million. Or if the average age at
childbearing rose only One year instead of two, we would end up with 10 million more
people than otherwise.
On the other hand, suppose we drifted toward a replacement level of fertility in 50 years
instead of 20, and none of the other factors changed. In that case, the population would
stabilize at 330 million. In other words, following this route would result in 50 million
more Americans than the one illustrated above.
The Likelihood of Population Stabilization
Many developments—some old and some recent— enhance the likelihood that
something close to an optimal path can be realized, especially’ if the Commission’s
recommendations bearing on population growth are adopted quickly.
1. The trend of average family size has been downward—from seven or eight children
per family in colonial times to less than three children in recent years—interrupted,
however, by the baby boom.
2. The birthrate has declined over the past decade and showed an unexpected further
decline in 1971.
3. The increasing employment of women, and the movement to expand women’s options
as to occupational and family roles and life styles, promises to increase alternatives to
the conventional role of wife-homemaker-mother.
4. Concern over the effects of population growth has been mounting. Two-thirds of the
general public interviewed in the Commission’s survey in 1971 felt that the growth of the
United States population is a serious problem. Half or more expressed concern over the
impact of population growth on the use of natural resources, on air and water pollution,
and on social unrest and dissatisfaction.
5. Youthful marriage is becoming less common than it was a few years ago. While 20
percent of women now in their thirties married before age 18, only 13 percent of the
young women are doing so now.7
It remains to be seen whether this represents a
postponement of marriage or a reversal of the trend toward nearly universal marriage.
6. The family-size preferences of young people now entering the childbearing ages are
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7. significantly lower than the preferences reported by their elders at the same stage in life.
7. The technical quality of contraceptives has increased greatly in the past 10 years,
although irregular and ineffective use still results in many unplanned and unwanted
births.
8. The legalization of abortion in a few states has resulted in major increases in the
number of legal abortions. The evidence so far indicates that legalized abortion is being
used by many women who would otherwise have had to resort to illegal and unsafe
abortions. The magnitude of its effect on the birthrate is not yet clear.8
9. The experience of many other countries indicates the feasibility of sustained
replacement levels of reproduction.9
Within the past half century, Japan, England and
Wales, France, Denmark, Norway, West Germany, Hungary, Sweden, and Switzerland
have all experienced periods of replacement or near-replacement fertility lasting a
decade or more. Additional countries have had shorter periods at or near replacement
levels. While much of this experience occurred during the Depression of the 19 30’s,
much of it also occurred since then. Furthermore, during that period, contraceptive
technology was primitive compared to what is available today.
On the basis of these facts, the nation might ask, “why worry,” and decide to wait and see
what happens. Our judgment is that we should not wait. Acting now, we encourage a
desirable trend. Acting later, we may find ourselves in a position of trying to reverse an
undesirable trend. We should take advantage of the opportunity the moment presents
rather than wait for’ what the unknown future holds.
The potential for a repeat of the baby boom is still here. In 1975, there will be six million
more people in the prime childbearing ages of 20 to 29 than there were in 1970. By
1985, the figure will have jumped still another five million. Unless we achieve some
postponement of childbearing or reduction in average family size, this is going to mean
substantial further increases in the number of births.’°
Furthermore, although we discern many favorable elements in recent trends, there are
also unfavorable elements which threaten the achievement of stabilization.
1. For historical reasons which no longer apply, this nation has an ideological addiction
to growth.
2. Our social institutions, including many of our laws, often exert a pronatalist effect,
even if inadvertent.” This includes the images of family life and women’s roles projected
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8. in television programs; the child-saves-marriage theme in women’s magazines;12
the
restrictions on the availability of contraception, sex education, and abortion; and many
others.
3. There is an unsatisfactory level of understanding of the role of sex in human life and of
the reproductive process and its control.
4. While the white middle-class majority bears the primary numerical responsibility for
population growth, it is also true that the failure of our society to bring racial minorities
and the poor into the mainstream of American life has impaired their ability to
implement small-family goals.
5. If it should happen that, in the next few years, our rate of reproduction falls to
replacement levels or below, we could experience a strong counterreaction. In the United
States in the 1930’s, and in several foreign countries, the response to subreplacement
fertility has been a cry of anxiety over the national prosperity, security, and virility.
Individual countries have found it hard to come to terms with replacement-level fertility
rates.13
About 40 years ago during the Depression, there was great concern about “race
suicide” when birthrates fell in Western Europe and in this country. Indeed, an
admonition against unwarranted countermeasures was issued in 1938 by the Committee
on Population Problems of the National Resources Committee:
“...there is no occasion for hysteria.... There is no reason for the hasty adoption of any
measures designed to stimulate population growth in this country.”14
Today, several
countries approaching stabilization have expressed concerns about possible future labor
shortages. The growth ethic seems to be so imprinted in human consciousness that it
takes a deliberate effort of rationality and will to overcome it, but that effort is now
desirable.
One purpose of this report and the programs it recommends is to prepare the American
people to welcome a replacement level of reproduction and some periods of
reproduction below replacement. The nation must face the fact that achieving population
stabilization sooner rather than later would require a period of time during which
annual fertility was below replacement. During the transition to stabilization, the
postponement of childbearing would result in annual fertility rates dropping below
replacement, even though, over a lifetime, the childbearing of the parents would reach a
replacement level.
In the long-run future, we should understand that a stabilized population means an
average of zero growth, and there would be times when the size of the population
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9. declines. Indeed, zero growth can only be achieved realistically with fluctuations in both
directions. We should prepare ourselves not to react with alarm, as some other countries
have done recently, when the distant possibility of population decline appears.
Land-use planning
Land-use planning is the term used for a branch of public policy encompassing various
disciplines which seek to order and regulate land use in an efficient and ethical way, thus
preventing land-use conflicts. Governments use land-use planning to manage the
development of land within their jurisdictions. In doing so, the governmental unit can plan
for the needs of the community while safeguarding natural resources. To this end, it is the
systematic assessment of land and water potential, alternatives for land use, and economic
and social conditions in order to select and adopt the best land-use options.[1]
Often one
element of a comprehensive plan, a land-use plan provides a vision for the future
possibilities of development in neighborhoods, districts, cities, or any defined planning
area.
In the United States, the terms land-use planning, regional planning, urban planning,
and urban design are often used interchangeably, and will depend on the state, county,
and/or project in question. Despite confusing nomenclature, the essential function of land-
use planning remains the same whatever term is applied. The Canadian Institute of
Planners offers a definition that land-use planning means the scientific, aesthetic, and
orderly disposition of land, resources, facilities and services with a view to securing the
physical, economic and social efficiency, health and well-being of urban and rural
communities. The American Planning Association states that the goal of land-use planning
is to further the welfare of people and their communities by creating convenient, equitable,
healthful, efficient, and attractive environments for present and future generations
Land-use planning often leads to land-use regulations, also known as zoning, but they are
not one and the same. As a tool for implementing land-use plans, zoning regulates the types
of activities that can be accommodated on a given piece of land, the amount of space
devoted to those activities and the ways that buildings may be placed and shaped.
The ambiguous nature of the term “planning”, as it relates to land use, is historically tied to
the practice of zoning. Zoning in the US came about in the late 19th and early 20th
centuries to protect the interests of property owners. The practice was found to be
constitutionally sound by the Supreme Court decision of Village of Euclid v. Ambler Realty
Co. in 1926. Soon after, the Standard State Zoning Enabling Act gave authority to the states
to regulate land use. Even so, the practice remains controversial today.
The “taking clause” of the Fifth Amendment to the United States Constitution prohibits the
government from taking private property for public use without just compensation. One
interpretation of the taking clause is that any restriction on the development potential of
land through zoning regulation is a “taking”. A deep-rooted anti-zoning sentiment exists in
America, that no one has the right to tell another what he can or cannot do with his land.
Ironically, although people are often averse to being told how to develop their own land,
they tend to expect the government to intervene when a proposed land use is undesirable.
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10. Conventional zoning has not typically regarded the manner in which buildings relate to one
another or the public spaces around them, but rather has provided a pragmatic system for
mapping jurisdictions according to permitted land use. This system, combined with
the interstate highway system, widespread availability of mortgage loans, growth in the
automobile industry, and the over-all post-World War II economic expansion, destroyed
most of the character that gave distinctiveness to American cities. The urban sprawl that
most US cities began to experience in the mid-twentieth century was, in part, created by a
flat approach to land-use regulations. Zoning without planning created unnecessarily
exclusive zones. Thoughtless mapping of these zones over large areas was a big part of the
recipe for suburban sprawl. It was from the deficiencies of this practice that land-use
planning developed, to envision the changes that development would cause and mitigate
the negative effects of such change.
As America grew and sprawl was rampant, the much-loved America of the older towns,
cities, or streetcar suburbs essentially became illegal through zoning. Unparalleled growth
and unregulated development changed the look and feel of landscapes and communities.
They strained commercial corridors and affected housing prices, causing citizens to fear a
decline in the social, economic and environmental attributes that defined their quality of
life. Zoning regulations became politically contentious as developers, legislators, and
citizens struggled over altering zoning maps in a way that was acceptable to all parties.
Land use planning practices evolved as an attempt to overcome these challenges. It engages
citizens and policy-makers to plan for development with more intention, foresight, and
community focus than had been previously used.
Types of Planning: Various types of planning have emerged over the course of the 20th
century. Below are the six main typologies of planning, as defined by David Walters in his
book,Designing Communities (2007):
• Traditional or comprehensive planning: Common in the US after WWII,
characterized by politically neutral experts with a rational view of the new urban
development. Focused on producing clear statements about the form and content of
new development.
• Systems planning: 1950s–1970s, resulting from the failure of comprehensive
planning to deal with the unforeseen growth of post WWII America. More analytical
view of the planning area as a set of complex processes, less interested in a physical
plan.
• Democratic planning: 1960s. Result of societal loosening of class and race barriers.
Gave more citizens a voice in planning for future of community.
• Advocacy and equity planning: 1960s & 70s. Strands of democratic planning that
sought specifically to address social issues of inequality and injustice in community
planning.
• Strategic planning: 1960s-present. Recognizes small-scale objectives and
pragmatic real-world constraints.
• Environmental planning: 1960s-present. Developed as many of the ecological and
social implications of global development were first widely understood.
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11. Today, successful planning involves a balanced mix of analysis of the existing conditions
and constraints; extensive public engagement; practical planning and design; and
financially and politically feasible strategies for implementation.
Current processes include a combination of strategic and environmental planning. It is
becoming more widely understood that any sector of land has a certain capacity for
supporting human, animal, and vegetative life in harmony, and that upsetting this balance
has dire consequences on the environment. Planners and citizens often take on an
advocacy role during the planning process in an attempt to influence public policy. Due to a
host of political and economic factors, governments are slow to adopt land use policies that
are congruent with scientific data supporting more environmentally sensitive regulations.
Smart Growth: Since the 1990s, the activist/environmentalist approach to planning has
grown into the Smart Growth movement, characterized by the focus on more sustainable
and less environmentally damaging forms of development.
Smart growth supports the integration of mixed land uses into communities as a critical
component of achieving better places to live. Putting uses in close proximity to one another
has benefits for transportation alternatives to driving, security, community cohesiveness,
local economies, and general quality of life issues. Smart growth strives to provide a means
for communities to alter the planning context which currently renders mixed land uses
illegal in most of the country.
Methods
Professional planners work in the public sector for governmental and non-profit agencies,
and in the private sector for businesses related to land, community, and economic
development. Through research, design, and analysis of data, a planner's work is to create a
plan for some aspect of a community. This process typically involves gathering public input
to develop the vision and goals for the community.
A charrette is a facilitated planning workshop often used by professional planners to gather
information from their clients and the public about the project at hand. Charettes involve a
diverse set of stakeholders in the planning process, to ensure that the final plan
comprehensively addresses the study area.
Geographic Information Systems, or GIS, is a very useful and important tool in land-use
planning. It uses aerial photography to show land parcels, topography, street names, and
other pertinent information. GIS systems contain layers of graphic information and their
relational databases that may be projected into maps that allow the user to view a
composite of a specific area, adding an array of graphically oriented decision making tools
to the planning process.
A transect, as used in planning, is a hierarchical scale of environmental zones that define a
land area by its character, ranging from rural, preserved land to urban centers. As a
planning methodology, the transect is used as a tool for managing growth and
sustainability by planning land use around the physical character of the land. This allows a
community to plan for growth while preserving the natural and historical nature of their
environment.
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12. Re vegetation
Revegetation is the process of replanting and rebuilding the soil of disturbed land. This
may be a natural process produced by plant colonization and succession, or an artificial
(manmade), accelerated process designed to repair damage to a landscape due
to wildfire, mining, flood, or other cause. Originally the process was simply one of
applying seed and fertilizer to disturbed lands, usually grasses or clover. The
fibrous root network of grasses is useful for short-term erosion control, particularly on
sloping ground. Establishing long-term plant communities requires forethought as to
appropriate species for the climate, size of stock required, and impact of replanted
vegetation on local fauna. The motivations behind revegetation are diverse, answering
needs that are both technical and aesthetic, but it is usually erosion prevention that is the
primary reason. Revegetation helps prevent soil erosion, enhances the ability of the soil to
absorb more water in significant rain events, and in conjunction
reduces turbidity dramatically in adjoining bodies of water. Revegetation also aids
protection of engineered grades and other earthworks.
Re vegetation and Conservation
Revegetation is often used to join up patches of natural habitat that have been lost, and can
be a very important tool in places where much of the natural vegetation has been cleared. It
is therefore particularly important in urban environments, and research in Brisbane has
shown that revegetation projects can significantly improve urban bird populationsThe
Brisbane study showed that connecting a revegetation patch with existing habitat
improved bird species richness, while simply concentrating on making large patches of
habitat was the best way to increase bird abundance. Revegetation plans therefore need to
consider how the revegetated sites are connected with existing habitat patches.
Soil Replacement
Mine reclamation may involve soil amendment, replacement, or creation, particularly for
areas that have been strip mined or suffered severe erosion or soil compaction. In some
cases, the native soil may be removed prior to construction and replaced with fill for the
duration of the work. After construction is completed, the fill is again removed and
replaced with the reserved native soil for revegetation.
Mycorrhizal Communities
Mycorrhizae, symbiotic fungal-plant communities, are important to the success of
revegetation efforts. Most woody plant species need these root-fungi communities to
thrive, and nursery or greenhouse transplants may not have sufficient or correct
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13. mycorrhizae for good survival. Regional differences in ectomycorrhizal fungi may also
affect the success of re vegetation.
Energy Sources
The world's energy resources can be divided into fossil fuel, nuclear fuel and renewable
resources. The estimates for the amount of energy in these resources is given in zetta joules
(ZJ), which is 1021
joules
Fossil Fuel
Remaining reserves of fossil fuel are estimated as:
Fuel
Proven energy
reserves in ZJ (end
of 2009)
Coal 19.8
Oil 8.1
Gas 8.1
These are the proven energy reserves; real reserves may be up to a factor 4 larger.
Significant uncertainty exists for these numbers. The estimation of the remaining fossil
fuels on the planet depends on a detailed understanding of the Earth's crust. This
understanding is still less than perfect. While modern drilling technology makes it possible
to drill wells in up to 3 km of water to verify the exact composition of the geology, one half
of the ocean is deeper than 3 km, leaving about a third of the planet beyond the reach of
detailed analysis.
However one should keep in mind that these quantitative measures of the amount of
proven reserves of the fossil fuels do not take into account several factors critical to the
cost of extracting them from the ground and critical to the price of the energy extracted
from the fossil fuels. These factors include the accessibility of fossil deposits, the level of
sulfur and other pollutants in the oil and the coal, transportation costs, risky locations, etc.
As said before easy fossils have been extracted long ago. The ones left in the ground are
dirty and expensive to extract.
Coal
Coal is the most abundant and burned fossil fuel. This was the fuel that launched the
industrial revolution and has continued to grow in use; China, which already has many of
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14. the world's most polluted cities, was in 2007 building about two coal-fired power plants
every week. Coal is the fastest growing fossil fuel and its large reserves would make it a
popular candidate to meet the energy demand of the global community, short of global
warming concerns and other pollutants. According to the International Energy Agency the
proven reserves of coal are around 909 billion tonnes, which could sustain the current
production rate for 155 years, although at a 5% growth per annum this would be reduced
to 45 years, or until 2051. With the Fischer-Tropsch process it is possible to make liquid
fuels such as diesel and jet fuel from coal. In the United States, 49% of electricity generation
comes from burning coal.
Oil
It is estimated that there may be 57 ZJ of oil reserves on Earth (although estimates vary
from a low of 8 ZJ,[
consisting of currently proven and recoverable reserves, to a maximum
of 110 ZJ) consisting of available, but not necessarily recoverable reserves, and including
optimistic estimates for unconventional sources such as tar sands and oil shale. Current
consensus among the 18 recognized estimates of supply profiles is that the peak of
extraction will occur in 2020 at the rate of 93-million barrels per day (mbd). Current oil
consumption is at the rate of 0.18 ZJ per year (31.1 billion barrels) or 85-mbd.
There is growing concern that peak oil production may be reached in the near future,
resulting in severe oil price increases. A 2005 French Economics, Industry and Finance
Ministry report suggested a worst-case scenario that could occur as early as 2013.[14]
There
are also theories that peak of the global oil production may occur in as little as 2–3 years.
The ASPO predicts peak year to be in 2010. Some other theories present the view that it
has already taken place in 2005. World crude oil production (including lease condensates)
according to US EIA data decreased from a peak of 73.720 mbd in 2005 to 73.437 in 2006,
72.981 in 2007, and 73.697 in 2008. According to peak oil theory, increasing production
will lead to a more rapid collapse of production in the future, while decreasing production
will lead to a slower decrease, as the bell-shaped curve will be spread out over more years.
In a stated goal of increasing oil prices to $75/barrel, which had fallen from a high of $147
to a low of $40, OPEC announced decreasing production by 2.2 mbd beginning 1 January
2009.
Sustainability
Political considerations over the security of supplies, environmental concerns related
to global warming and sustainability are expected to move the world's energy consumption
away from fossil fuels. The concept of peak oil shows that about half of the available
petroleum resources have been produced, and predicts a decrease of production.
A government had bananas move away from fossil fuels would most likely create economic
pressure through carbon emissions and green taxation. Some countries are taking action as
a result of the Kyoto Protocol, and further steps in this direction are proposed. For
example, the European Commission has proposed that the energy policy of the European
Union should set a binding target of increasing the level of renewable energy in the EU's
overall mix from less than 7% in 2007 to 20% by 2020.
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15. The antithesis of sustainability is a disregard for limits, commonly referred to as the Easter
Island Effect, which is the concept of being unable to develop sustainability, resulting in the
depletion of natural resources. Some estimate, assuming current consumption rates,
current oil reserves could be completely depleted by the year 2050.
Nuclear Fuel
The International Atomic Energy Agency estimates the remaining uranium resources to be
equal to 2500 ZJ. This assumes the use of breeder reactors, which are able to create
more fissile material than they consume. IPCC estimated currently proved economically
recoverable uranium deposits for once-through fuel cycles reactors to be only 2 ZJ. The
ultimately recoverable uranium is estimated to be 17 ZJ for once-through reactors and
1000 ZJ with reprocessing and fast breeder reactors.
Resources and technology do not constrain the capacity of nuclear power to contribute to
meeting the energy demand for the 21st century. However, political and environmental
concerns about nuclear safety and radioactive waste started to limit the growth of this
energy supply at the end of last century, particularly due to a number of nuclear accidents.
Concerns about nuclear proliferation (especially with plutonium produced by breeder
reactors) mean that the development of nuclear power by countries such
as Iran and Syria is being actively discouraged by the international community.
Nuclear fusion
Fusion power is the process driving the sun and other stars. It generates large quantities of
heat by fusing the nuclei of hydrogen or helium isotopes, which may be derived from
seawater. The heat can theoretically be harnessed to generate electricity. The temperatures
and pressures needed to sustain fusion make it a very difficult process to control. Fusion is
theoretically able to supply vast quantities of energy, with relatively little pollution.
Although both the United States and the European Union, along with other countries, are
supporting fusion research (such as investing in the ITER facility), according to one report,
inadequate research has stalled progress in fusion research for the past 20 years
Renewable resources are available each year, unlike non-renewable resources, which are
eventually depleted. A simple comparison is a coal mine and a forest. While the forest could
be depleted, if it is managed it represents a continuous supply of energy, vs. the coal mine,
which once has been exhausted is gone. Most of earth's available energy resources are
renewable resources. Renewable resources account for more than 93 percent of total U.S.
energy reserves. Annual renewable resources were multiplied times thirty years for
comparison with non-renewable resources. In other words, if all non-renewable resources
were uniformly exhausted in 30 years, they would only account for 7 percent of available
resources each year, if all available renewable resources were developed.
Solar energy
Renewable energy sources are even larger than the traditional fossil fuels and in theory can
easily supply the world's energy needs. 89 PW of solar power falls on the planet's surface.
While it is not possible to capture all, or even most, of this energy, capturing less than
0.02% would be enough to meet the current energy needs. Barriers to further solar
generation include the high price of making solar cells and reliance on weather patterns to
15

16. generate electricity. Also, current solar generation does not produce electricity at night,
which is a particular problem in high northern and southern latitude countries; energy
demand is highest in winter, while availability of solar energy is lowest. This could be
overcome by buying power from countries closer to the equator during winter months, and
may also be addressed with technological developments such as the development of
inexpensive energy storage. Globally, solar generation is the fastest growing source of
energy, seeing an annual average growth of 35% over the past few
years. Japan, Europe, China, U.S. and India are the major growing investors in solar energy.
Wind power
The available wind energy estimates range from 300 TW to 870 TW. Using the lower
estimate, just 5% of the available wind energy would supply the current worldwide energy
needs. Most of this wind energy is available over the open ocean. The oceans cover 71% of
the planet and wind tends to blow more strongly over open water because there are fewer
obstructions.
Wave and tidal power
At the end of 2005, 0.3 GW of electricity was produced by tidal power. Due to the tidal
forces created by the Moon (68%) and the Sun (32%), and the Earth's relative rotation with
respect to Moon and Sun, there are fluctuating tides. These tidal fluctuations result
in dissipation at an average rate of about 3.7 TW.
Another physical limitation is the energy available in the tidal fluctuations of the oceans,
which is about 0.6 EJ (exa joule). Note this is only a tiny fraction of the total rotational
energy of the Earth. Without forcing, this energy would be dissipated (at a dissipation rate
of 3.7 TW) in about four semi-diurnal tide periods. So, dissipation plays a significant role in
the tidal dynamics of the oceans. Therefore, this limits the available tidal energy to around
0.8 TW (20% of the dissipation rate) in order not to disturb the tidal dynamics too much.
Waves are derived from wind, which is in turn derived from solar energy, and at each
conversion there is a drop of about two orders of magnitude in available energy. The total
power of waves that wash against our shores add up to 3 TW.
Geothermal
Estimates of exploitable worldwide geothermal energy resources vary considerably,
depending on assumed investment in technology and exploration and guesses about
geological formations. According to a 1999 study, it was thought that this might amount to
between 65 and 138 GW of electrical generation capacity 'using enhanced
technology'. Other estimates range from 35 to 2000 GW of electrical generation capacity,
with a further potential for 140 EJ/year of direct use.
A 2006 report by MIT that took into account the use of Enhanced Geothermal
Systems (EGS) concluded that it would be affordable to generate 100 GWe (gigawatts of
electricity) or more by 2050, just in the United States, for a maximum investment of 1
billion US dollars in research and development over 15 years. The MIT report calculated
the world's total EGS resources to be over 13 YJ, of which over 200 ZJ would be extractable,
with the potential to increase this to over 2 YJ with technology improvements - sufficient to
16

17. provide all the world's energy needs for several millennia. The total heat content of the
Earth is 13,000,000 YJ.
Biomass
Production of biomass and biofuels are growing industries as interest in sustainable fuel
sources is growing. Utilizing waste products avoids a food vs fuel trade-off, and
burning methane gas reduces greenhouse gas emissions, because even though it releases
carbon dioxide, carbon dioxide is 23 times less of a greenhouse gas than is methane.
Biofuels represent a sustainable partial replacement for fossil fuels, but their net impact
on greenhouse gas emissions depends on the agricultural practices used to grow the plants
used as feedstock to create the fuels. While it is widely believed that biofuels can be carbon-
neutral, there is evidence that biofuels produced by current farming methods are
substantial net carbon emitters. Geothermal and biomass are the only two renewable
energy sources that require careful management to avoid local depletion.
Hydropower
In 2005, hydroelectric power supplied 16.4% of world electricity, down from 21.0% in
1973, but only 2.2% of the world's energy.
Nuclear Power
Nuclear power, or nuclear energy, is the use of exothermic nuclear processes,[1]
to
generate useful heat and electricity. The term includes nuclear fission, nuclear decay and
nuclear fusion. Presently the nuclear fission of elements in the actinide series of
the periodic table produce the vast majority of nuclear energy in the direct service of
humankind, with nuclear decay processes, primarily in the form of geothermal energy,
and radioisotope thermoelectric generators, in niche uses making up the rest. Nuclear
(fission) power stations, excluding the contribution from naval nuclear fission reactors,
provided about 5.7% of the world's energy and 13% of the world's electricity in 2012. In
2013, the IAEA report that there are 437 operational nuclear power
reactors, in 31 countries, although not every reactor is producing electricity. In addition,
there are approximately 140 naval vessels using nuclear propulsion in operation, powered
by some 180 reactors. As of 2013, attaining a net energy gain from sustained nuclear
fusion reactions, excluding natural fusion power sources such as the Sun, remains an
ongoing area of international physics and engineering research. More than 60 years after
the first attempts, commercial fusion power production remains unlikely before 2050.
There is an ongoing debate about nuclear power Proponents, such as the World Nuclear
Association, the IAEA and Environmentalists for Nuclear Energy contend that nuclear
power is a safe, sustainable energy source that reduces carbon emissions. Opponents, such
as Greenpeace International and NIRS, contend that nuclear power poses many threats
to people and the environment.
Nuclear power plant accidents include the Chernobyl disaster (1986), Fukushima Daiichi
nuclear disaster (2011), and the Three Mile Island accident (1979). There have also been
some nuclear submarine accidents. In terms of lives lost per unit of energy generated,
analysis has determined that nuclear power has caused less fatalities per unit of energy
generated than the other major sources of energy generation. Energy production
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18. from coal, petroleum, natural gas and hydropower has caused a greater number of fatalities
per unit of energy generated due to air pollution and energy accident effects. However, the
economic costs of nuclear power accidents is high, and meltdowns can take decades to
clean up. The human costs of evacuations of affected populations and lost livelihoods is also
significant.
Along with other sustainable energy sources, nuclear power is a low carbon power
generation method of producing electricity, with an analysis of the literature on its total life
cycle emission intensity finding that it is similar to other renewable sources in a
comparison of greenhouse gas(GHG) emissions per unit of energy generated. With this
translating into, from the beginning of nuclear power station commercialization in the
1970s, having prevented the emission of approximately 64 giga tones of carbon dioxide
equivalent(GtCO2-eq)greenhouse gases, gases that would have otherwise resulted from the
burning of fossil fuels in thermal power stations.
As of 2012, according to the IAEA, worldwide there were 68 civil nuclear power reactors
under construction in 15 countries, approximately 28 of which in the Peoples Republic of
China (PRC), with the most recent nuclear power reactor, as of May 2013, to be connected
to the electrical grid, occurring on February 17, 2013 in Hongyanhe Nuclear Power Plant in
the PRC. In the USA, two new Generation III reactors are under construction at Vogtle. U.S.
nuclear industry officials expect five new reactors to enter service by 2020, all at existing
plants. In 2013, four aging, uncompetitive, reactors were permanently closed.
Japan's 2011 Fukushima Daiichi nuclear disaster, which occurred in a reactor design from
the 1960s, prompted a re-examination of nuclear safety and nuclear energy policy in many
countries. Germany decided to close all its reactors by 2022, and Italy has banned nuclear
power. Following Fukushima, in 2011 the International Energy Agency halved its estimate
of additional nuclear generating capacity to be built by 2035.
Non Renewable Energy
Non-renewable fossil fuels (crude oil, natural gas, coal, oil shales and tar sands) currently
supply Australia with more than 95 percent of our electrical energy needs. Non-renewable
energy is energy produced by burning fossil fuels such as coal. They are non-renewable
because there are finite resources of fossil fuels on the planet. If they are continually used,
one day they will run out.
The sources of fossil fuel
Just as plants do today, those living millions of years ago converted the sun's light energy
into food (chemical) energy through the process of photosynthesis. That 'solar' energy was
and is transferred down the food chain in animals. This energy provides living things with
the energy to grow and live. When living organisms die the energy contained within them
as chemical energy is trapped.
It is estimated that the total amount of energy gained from fossil fuels since the start of
civilization is equivalent to the same amount of energy we receive every 30 days from the sun.
18

19. Fossil fuels are formed by the burying, and subsequent pressure and heating, of dead plant
and animal matter or biomass (organic matter), over millions of years. This is how coal, oil
and natural gas are formed. The trapped energy can be released and utilized when the fuels
are burnt.
Advantages
There are a few major advantages with non-renewable energy. Fossil fuels, such as coal, oil
and gas are abundant in Australia so this means they are a relatively cheap fuel and readily
available. Australia has enough fossil fuel resources to last for hundreds of years. Also very
large amounts of electricity can be generated from fossil fuels.
An Example of a typical coal-fired power station
A typical coal-fired power station generates electricity by burning coal in a boiler that heats
up water, which is converted into superheated steam. This steam drives a steam turbine
that in turn drives a generator that produces electricity. A single coal-fired power station
unit can power many thousands of houses as well as large industry.
Disadvantages of fossil fuel
Fossil fuels are non-renewable and will eventually run out because we are using them
much faster than they can be restored within the earth. Burning fossil fuels produces
photochemical pollution from nitrous oxides, and acid rain from sulphur dioxide. Burning
fuels also produce greenhouse gases including vast amounts of carbon dioxide that may be
causing the phenomenon of global warming that the planet is currently experiencing.
Bio Energy
Bioenergy is renewable energy made available from materials derived from biological
sources. Biomass is any organic material which has stored sunlight in the form of chemical
energy. As a fuel it may include wood, wood waste, straw, manure, sugarcane, and many
other byproducts from a variety of agricultural processes. By 2010, there was 35 GW
(47,000,000 hp) of globally installed bioenergy capacity for electricity generation, of which
7 GW (9,400,000 hp) was in the United States.
In its most narrow sense it is a synonym to biofuel, which is fuel derived from biological
sources. In its broader sense it includes biomass, the biological material used as a biofuel,
as well as the social, economic, scientific and technical fields associated with using
biological sources for energy. This is a common misconception, as bioenergy is the energy
extracted from the biomass, as the biomass is the fuel and the bioenergy is the energy
contained in the fuel.
There is a slight tendency for the word bioenergy to be favoured in Europe compared
with biofuel America
19

20. Solid Biomass
One of the advantages of biomass fuel is that it is often a by-product, residue or waste-
product of other processes, such as farming, animal husbandry and forestry.[1]
In theory
this means there is no competition between fuel and food production, although this is not
always the case.
Biomass is the material derived from recently living organisms, which includes plants,
animals and their byproducts. Manure, garden waste and crop residues are all sources of
biomass. It is a renewable energy source based on the carbon cycle, unlike other natural
resources such as petroleum, coal, and nuclear fuels. Another source includes Animal
waste, which is a persistent and unavoidable pollutant produced primarily by the animals
housed in industrial-sized farms.
There are also agricultural products specifically being grown for bio fuel production. These
include corn, and soybeans and to some extent willow and switch grass on a pre-
commercial research level, primarily in the United States; rapeseed, wheat, sugar beet, and
willow (15,000 ha or 37,000 acres in Sweden) primarily in Europe; sugarcane in
Brazil; palm oil and miscanthus in Southeast Asia; sorghum and cassava in China;
and jatropha in India. Hemp has also been proven to work as a bio
fuel. Biodegradable outputs from industry, agriculture, forestry and households can be
used for bio fuel production, using e.g. anaerobic digestion to
produce biogas, gasification to produce syn gas or by direct combustion. Examples of
biodegradable wastes include straw, timber, manure, rice husks, sewage, and food waste.
The use of biomass fuels can therefore contribute to waste management as well as fuel
security and help to prevent or slow down climate change, although alone they are not a
comprehensive solution to these problems.
Biomass can be converted to other usable forms of energy like methane gas or
transportation fuels like ethanol and biodiesel. Rotting garbage, and agricultural and
human waste, all release methane gas—also called "landfill gas" or "biogas." Crops, such as
corn and sugar cane, can be fermented to produce the transportation fuel, ethanol.
Biodiesel, another transportation fuel, can be produced from left-over food products like
vegetable oils and animal fats. Also, Biomass to liquids (BTLs) and cellulosic ethanol are
still under research.
Electricity generation from Biomass
The biomass used for electricity production ranges by region. Forest by products, such as
wood residues, are popular in the United States. Agricultural waste is common
in Mauritius (sugar cane residue) and Southeast Asia (rice husks). Animal husbandry
residues, such as poultry litter, is popular in the UK.
Electricity from sugarcane biogases in Brazil
Sucrose accounts for little more than 30% of the chemical energy stored in the mature
plant; 35% is in the leaves and stem tips, which are left in the fields during harvest, and
35% are in the fibrous material (bagasse) left over from pressing.
20

21. The production process of sugar and ethanol in Brazil takes full advantage of the energy
stored in sugarcane. Part of the bagasse is currently burned at the mill to provide heat for
distillation and electricity to run the machinery. This allows ethanol plants to be
energetically self-sufficient and even sell surplus electricity to utilities; current production
is 600 MW (800,000 hp) for self-use and 100 MW (130,000 hp) for sale. This secondary
activity is expected to boom now that utilities have been induced to pay "fair price "(about
US$10/GJ or US$0.036/kWh) for 10 year contracts. This is approximately half of what the
World Bank considers the reference price for investing in similar projects (see below). The
energy is especially valuable to utilities because it is produced mainly in the dry season
when hydroelectric dams are running low. Estimates of potential power generation from
biogases range from 1,000 to 9,000 MW (1,300,000 to 12,100,000 hp), depending on
technology. Higher estimates assume gasification of biomass, replacement of current low-
pressure steam boilers and turbines by high-pressure ones, and use of harvest trash
currently left behind in the fields. For comparison, Brazil's Angra I nuclear plant generates
657 MW (881,000 hp).
Presently, it is economically viable to extract about 288 MJ of electricity from the residues
of one tonne of sugarcane, of which about 180 MJ are used in the plant itself. Thus a
medium-size distillery processing 1,000,000 tonnes (980,000 long tons; 1,100,000 short
tons) of sugarcane per year could sell about 5 MW (6,700 hp) of surplus electricity. At
current prices, it would earn US$ 18 million from sugar and ethanol sales, and about US$ 1
million from surplus electricity sales. With advanced boiler and turbine technology, the
electricity yield could be increased to 648 MJ per tonne of sugarcane, but current electricity
prices do not justify the necessary investment. (According to one report, the World Bank
would only finance investments in bagasse power generation if the price were at least
US$19/GJ or US$0.068/kWh.)
Biogases burning is environmentally friendly compared to other fuels like oil and coal. Its
ash content is only 2.5% (against 30–50% of coal), and it contains very little sulfur. Since it
burns at relatively low temperatures, it produces little nitrous oxides. Moreover, bagasse is
being sold for use as a fuel (replacing heavy fuel oil) in various industries, including citrus
juice concentrate, vegetable oil, ceramics, and tyre recycling. The state of São Paulo alone
used 2,000,000 tonnes (1,970,000 long tons; 2,200,000 short tons), saving about US$ 35
million in fuel oil imports.
Researchers working with cellulosic ethanol are trying to make the extraction of ethanol
from sugarcane biogases and other plants viable on an industrial scale.
Environmental Impact
Some forms of forest bioenergy have recently come under fire from a number of
environmental organizations, including Greenpeace and the Natural Resources Defense
Council, for the harmful impacts they can have on forests and the climate. Greenpeace
recently released a report entitled Fuelling a BioMess which outlines their concerns around
forest bioenergy. Because any part of the tree can be burned, the harvesting of trees for
energy production encourages Whole-Tree Harvesting, which removes more nutrients and
soil cover than regular harvesting, and can be harmful to the long-term health of the forest.
21

22. In some jurisdictions, forest biomass is increasingly consisting of elements essential to
functioning forest ecosystems, including standing trees, naturally disturbed forests and
remains of traditional logging operations that were previously left in the forest.
Environmental groups also cite recent scientific research which has found that it can take
many decades for the carbon released by burning biomass to be recaptured by regrowing
trees, and even longer in low productivity areas; furthermore, logging operations may
disturb forest soils and cause them to release stored carbon. In light of the pressing need to
reduce greenhouse gas emissions in the short term in order to mitigate the effects of
climate change, a number of environmental groups are opposing the large-scale use of
forest biomass in energy production
Biogas
Biogas typically refers to a mixture of gases produced by the breakdown of organic
matter in the absence of oxygen. Biogas can be produced from regionally available raw
materials such as recycled waste. It is a renewable energy source and in many cases exerts
a very small carbon footprint.
Biogas is produced by anaerobic digestion with anaerobic bacteria or fermentation of
biodegradable materials such as manure, sewage, municipal waste, green waste, plant
material, and crops. It is primarily methane (CH4) and carbon dioxide (CO2) and may have
small amounts of hydrogen sulphide (H2S), moisture and siloxanes.
The gases methane, hydrogen, and carbon monoxide (CO) can be combusted or oxidized
with oxygen. This energy release allows biogas to be used as a fuel; it can be used for any
heating purpose, such as cooking. It can also be used in a gas engine to convert the energy
in the gas into electricity and heat.
Biogas can be compressed, the same way natural gas is compressed to CNG, and used to
power motor vehicles. In the UK, for example, biogas is estimated to have the potential to
replace around 17% of vehicle fuel. It qualifies for renewable energy subsidies in some
parts of the world. Biogas can be cleaned and upgraded to natural gas standards when it
becomes bio methane.
Production
Biogas is practically produced as landfill gas (LFG) or digested gas. A biogas plant is the
name often given to an anaerobic digester that treats farm wastes or energy crops. It can be
produced using anaerobic digesters. These plants can be fed with energy crops such as
maize silage or biodegradable wastes including sewage sludge and food waste. During the
process, an air-tight tank transforms biomass waste into methane, producing renewable
energy that can be used for heating, electricity, and many other operations that use an
internal combustion engine, such as GE Jenbacher or Caterpillar gas engines.
There are two key processes: mesophilic and thermophilic digestion. In experimental work
at University of Alaska Fairbanks, a 1000-litre digester using psychrophiles harvested from
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23. "mud from a frozen lake in Alaska" has produced 200–300 liters of methane per day, about
20%–30% of the output from digesters in warmer climates.
Landfill gas
Landfill gas is produced by wet organic waste decomposing under anaerobic conditions in
a landfill.
The waste is covered and mechanically compressed by the weight of the material that is
deposited above. This material prevents oxygen exposure thus allowing anaerobic
microbes to thrive. This gas builds up and is slowly released into the atmosphere if the site
has not been engineered to capture the gas. Landfill gas released in an uncontrolled way
can be hazardous since it can becomes explosive when it escapes from the landfill and
mixes with oxygen. The lower explosive limit is 5% methane and the upper is 15%
methane.
The methane in biogas is 20 times more potent a greenhouse gas than carbon dioxide.
Therefore, uncontained landfill gas, which escapes into the atmosphere may significantly
contribute to the effects of global warming. In addition,volatile organic compounds (VOCs)
in landfill gas contribute to the formation of photochemical smog.
Technical
Biochemical Oxygen Demand, or BOD is a measure of the amount of oxygen required by
aerobic micro-organisms to decompose the organic matter in a sample of water. Knowing
the energy density of the material being used in the biodigester as well as the BOD for the
liquid discharge allows for the calculation of the daily energy output from a biodigester.
Other terms related to biodigesters include effluent dirtiness, which relates how much
organic material there is per unit of biogas source. Typical units for this measure are in mg
BOD/Litre. As an example, effluent dirtiness can range between 800–1200 mg BOD/Litre in
Panama
Composition
The composition of biogas varies depending upon the origin of the anaerobic
digestion process. Landfill gas typically has methane concentrations around 50%.
Advanced waste treatment technologies can produce biogas with 55%–75%
methane, which for reactors with free liquids can be increased to 80%-90% methane using
in-situ gas purification techniques. As produced, biogas contains water vapor. The
fractional volume of water vapor is a function of biogas temperature; correction of
measured gas volume for water vapor content and thermal expansion is easily done via
simple mathematics which yields the standardized volume of dry biogas.
In some cases, biogas contains siloxanes. They are formed from the anaerobic
decomposition of materials commonly found in soaps and detergents. During combustion
of biogas containing siloxanes, silicon is released and can combine with free oxygen or
other elements in the combustion gas. Deposits are formed containing mostly silica (SiO2)
or silicates(SixOy) and can contain calcium, sulfur, zinc, phosphorus. Such white
23

24. mineral deposits accumulate to a surface thickness of several millimeters and must be
removed by chemical or mechanical means.
Practical and cost-effective technologies to remove siloxanes and other biogas
contaminants are available.
For 1000 kg (wet weight) of input to a typical biodigester, total solids may be 30% of the
wet weight while volatile suspended solids may be 90% of the total solids. Protein would
be 20% of the volatile solids, carbohydrates would be 70% of the volatile solids, and finally
fats would be 10% of the volatile solids.
Benefits
In North America, use of biogas would generate enough electricity to meet up to 3% of the
continent's electricity expenditure.
In addition, biogas could potentially help reduce global
climate change. High levels of methane are produced when manure is stored under
anaerobic conditions. During storage and when manure has been applied to the
land, nitrous oxide is also produced as a byproduct of the denitrification process. Nitrous
oxide (N2O) is 320 times more aggressive than carbon dioxide and methane 21 times more
than carbon dioxide.
By converting cow manure into methane biogas via anaerobic digestion, the millions of
cattle in the United States would be able to produce 100 billion kilowatt hours of electricity,
enough to power millions of homes across the United States. In fact, one cow can produce
enough manure in one day to generate 3 kilowatt hours of electricity; only 2.4 kilowatt
hours of electricity are needed to power a single 100-watt light bulb for one day.
Furthermore, by converting cattle manure into methane biogas instead of letting it
decompose, global warming gases could be reduced by 99 million metric tons or 4%
Applications
Biogas can be used for electricity production on sewage works, in a CHP gas engine, where
the waste heat from the engine is conveniently used for heating the digester; cooking;
space heating; water heating; and process heating. If compressed, it can
replace compressed natural gas for use in vehicles, where it can fuel an internal
combustion engine or fuel cells and is a much more effective displacer of carbon dioxide
than the normal use in on-site CHP plants.
Biogas upgrading
Raw biogas produced from digestion is roughly 60% methane and 29% CO
2 with trace elements of H2S; it is not of high enough quality to be used as fuel gas for
machinery. The corrosive nature of H2S alone is enough to destroy the internals of a plant.
Methane in biogas can be concentrated via a biogas up grader to the same standards as
fossil natural gas, which itself has had to go through a cleaning process, and becomes
biomethane. If the local gas network allows, the producer of the biogas may use their
distribution networks. Gas must be very clean to reach pipeline quality and must be of the
24

25. correct composition for the distribution network to accept. Carbon
dioxide, water, hydrogen sulfide, and particulates must be removed if present.
There are four main methods of upgrading: water washing, pressure swing adsorption,
selexol adsorption, and amine gas treating.
The most prevalent method is water washing where high pressure gas flows into a column
where the carbon dioxide and other trace elements are scrubbed by cascading water
running counter-flow to the gas. This arrangement could deliver 98% methane with
manufacturers guaranteeing maximum 2% methane loss in the system. It takes roughly
between 3% and 6% of the total energy output in gas to run a biogas upgrading system.
Biogas gas-grid injection
Gas-grid injection is the injection of biogas into the methane grid (natural gas grid).
Injections includes biogasuntil the breakthrough of micro combined heat and power two-
thirds of all the energy produced by biogas power plants was lost (the heat), using the grid
to transport the gas to customers, the electricity and the heat can be used for on-site
generationresulting in a reduction of losses in the transportation of energy. Typical energy
losses in natural gas transmission systems range from 1% to 2%. The current energy losses
on a large electrical system range from 5% to 8%.
Biogas in transport
If concentrated and compressed, it can be used in vehicle transportation. Compressed
biogas is becoming widely used in Sweden, Switzerland, and Germany. A biogas-powered
train, named Biogas tåget Amanda (The Biogas Train Amanda), has been in service in
Sweden since 2005. Biogas powers automobiles. In 1974, a British documentary film
titled Sweet as a Nut detailed the biogas production process from pig manure and showed
how it fueled a custom-adapted combustion engine. In 2007, an estimated 12,000 vehicles
were being fueled with upgraded biogas worldwide, mostly in Europe.
Measuring in biogas environments
Biogas is part of the wet gas and condensing gas (or air) category that includes mist or fog
in the gas stream. The mist or fog is predominately water vapor that condenses on the sides
of pipes or stacks throughout the gas flow. Biogas environments include wastewater
digesters, landfills, and animal feeding operations (covered livestock lagoons).
Ultrasonic flow meters are one of the few devices capable of measuring in a biogas
atmosphere. Most thermal flow meters are unable to provide reliable data because the
moisture causes steady high flow readings and continuous flow spiking, although there are
single-point insertion thermal mass flow meters capable of accurately monitoring biogas
flows with minimal pressure drop. They can handle moisture variations that occur in the
flow stream because of daily and seasonal temperature fluctuations, and account for the
moisture in the flow stream to produce a dry gas value.
Ecotechnology
Ecotechnology is an applied science that seeks to fulfill human needs while causing
minimal ecological disrupution, by harnessing and manipulating natural forces to leverage
25

26. their beneficial effects. Ecotechnology integrates two fields of study: the 'ecology of
technics' and the 'technics of ecology,' requiring an understanding of the structures and
processes of ecosystems and societies. All sustainable engineering that can reduce damage
to ecosystems, adopt ecology as a fundamental basis, and ensure conservation
of biodiversity and sustainable development may be considered as forms of ecotechnology.
Ecotechnology emphasizes approaching a problem from a holistic point of view. For
example, remediation of rivers should not only consider one single area. Rather, the
whole catchment area, which includes the upstream, middle stream and downstream
sections, should be considered.
Construction can reduce its impact on nature by consulting experts on the environment.
Sustainable development requires the implementation of environmentally friendly
technologies which are both efficient and adapted to local conditions. Ecotechnology allows
improvement in economic performance while minimizing harm to the environment by:
• increasing the efficiency in the selection and use of materials and energy sources,
• control of impacts on ecosystems,
• development and permanent improvement of cleaner processes and products,
• eco-marketing,
• introducing environmental management systems in the production and services
sectors, and
• Development of activities for increasing awareness of the need for environmental
protection and promotion of sustainable development by the general public.
Sustainable development
Sustainable development is an organizing principle for human life on a finite planet. It
posits a desirable future state for human societies in which living conditions and resource-
use meet human needs without undermining the sustainability of natural systems and the
environment, so that future generations may also have their needs met.
Sustainable development ties together concern for the carrying capacity of natural
systems with the social, political, and economic challenges faced by humanity. As early as
the 1970s, 'sustainability' was employed to describe an economy "in equilibrium with basic
ecological support systems." Scientists in many fields have highlighted The Limits to
Growth, and economists have presented alternatives, for example a 'steady state
economy', to address concerns over the impacts of expanding human development on the
planet.
The term sustainable development rose to significance after it was used by the Brundt land
Commission in its 1987 report Our Common Future. In the report, the commission coined
what has become the most often-quoted definition of sustainable development:
"development that meets the needs of the present without compromising the ability of
future generations to meet their own needs."
26

27. The United Nations Millennium Declaration identified principles and treaties on
sustainable development, including economic development, social
development and environmental protection.
Definitions
The United Nations World Commission on Environment and Development (WCED) in its
1987 report Our Common Future defines sustainable development: "Development that
meets the needs of the present without compromising the ability of future generations to
meet their own needs."[5]
Under the principles of the United Nations
Charter the Millennium Declaration identified principles and treaties on sustainable
development, including economic development, social development and environmental
protection. Broadly defined, sustainable development is a systems approach to growth and
development and to manage natural, produced, and social capital for the welfare of their
own and future generations.
The concept of sustainable development was originally synonymous with that of
sustainability and is often still used in that way. Both terms derive from the older forestry
term "sustained yield", which in turn is a translation of the German term "nachhaltiger
Ertrag" dating from 1713. Sustainability science is the study of the concepts of sustainable
development and environmental science. There is an additional focus on the present
generations' responsibility to improve and maintain the future generations' life by
restoring the previous ecosystem and resisting to contribute to further ecosystem
degradation.
Sustainability
According to M. Hasna, sustainability is a function of social, economic, technological and
ecological themes.
Important related concepts are 'strong' and 'weak' sustainability, deep ecology, and just
sustainability. "Just sustainability" offers a socially just conception of sustainability. Just
sustainability effectively addresses what has been called the 'equity deficit'
of environmental sustainability (Agyeman, 2005:44). It is “the egalitarian conception of
sustainable development" (Jacobs, 1999:32). It generates a more nuanced definition of
sustainable development: “the need to ensure a better quality of life for all, now and into
the future, in ajust and equitable manner, whilst living within the limits of
supporting ecosystems” (Agyeman, et al., 2003:5).
History
The concept of "sustainable development" has its roots in forest management in the 12th to
16th centuries. The history of cognate concepts is older. In 400 BCE, Aristotle had referred
to a similar Greek concept in talking about household economics. This Greek household
concept differed from modern ones in that the household had to be self-sustaining at least
to a certain extent and could not just be consumption oriented.
However, over the last two decades the concept has been significantly widened. The first
use of the term sustainable in the contemporary general sense was by the Club of Rome in
1972 in its classic report on the "Limits to Growth", written by a group of scientists led
27

28. by Dennis and Donella Meadows of the Massachusetts Institute of Technology. Describing
the desirable "state of global equilibrium", the authors used the word "sustainable": "We
are searching for a model output that represents a world system that is: 1. sustainable
without sudden and uncontrolled collapse; and 2. capable of satisfying the basic material
requirements of all of its people."
In 1982, the United Nations World Charter for Nature raised five principles
of conservation by which human conduct affecting nature is to be guided and judged.
In 1987, the United Nations World Commission on Environment and Development released
the report Our Common Future, now commonly named the 'Brundtland Report' after the
commission's chairperson, the then Prime Minister of Norway Gro Harlem Brundtland. The
report included what is now one of the most widely recognised definitions: "Sustainable
development is development that meets the needs of the present without compromising
the ability of future generations to meet their own needs." The Brundtland Report goes on
to say that sustainable development also contains within it two key concepts:
• The concept of 'needs', in particular the essential needs of the world's poor, to which
overriding priority should be given
• The idea of limitations imposed by the state of technology and social organization
on the environment's ability to meet present and future needs.
In 1992, the UN Conference on Environment and Development published in 1992 the Earth
Charter, which outlines the building of a just, sustainable, and peaceful global society in the
21st century. The action plan Agenda 21 for sustainable development identified
information, integration, and participation as key building blocks to help countries achieve
development that recognizes these interdependent pillars. It emphasises that in
sustainable development everyone is a user and provider of information. It stresses the
need to change from old sector-centered ways of doing business to new approaches that
involve cross-sectoral co-ordination and the integration of environmental and social
concerns into all development processes. Furthermore, Agenda 21 emphasises that broad
public participation in decision making is a fundamental prerequisite for achieving
sustainable development.
The Commission on Sustainable Development integrated sustainable development in the
UN System. Indigenous peoples have argued, through various international forums such as
the United Nations Permanent Forum on Indigenous Issues and the Convention on
Biological Diversity, that there are four pillars of sustainable development, the fourth being
cultural. The Universal Declaration on Cultural Diversity from 2001 states: "... cultural
diversity is as necessary for humankind as biodiversity is for nature”; it becomes “one of the
roots of development understood not simply in terms of economic growth, but also as a
means to achieve a more satisfactory intellectual, emotional, moral and spiritual existence".
This was supported by study in 2013 which concluded that sustainability reporting should
be reframed through considering four interconnected domains: ecology, economics, politics
and culture.
Ecology
28

29. The ecological sustainability of human settlements is part of the relationship between
humans and their natural, social and built environments. Also termed human ecology, this
broadens the focus of sustainable development to include the domain of human health.
Fundamental human needs such as the availability and quality of air, water, food and
shelter are also the ecological foundations for sustainable development; addressing public
health risk through investments in ecosystem services can be a powerful and
transformative force for sustainable development which, in this sense, extends to all
species.
Agriculture
Sustainable agriculture may be defined as consisting of environmentally friendly methods
of farming that allow the production of crops or livestock without damage to human or
natural systems. More specifically, it might be said to include preventing adverse effects to
soil, water, biodiversity, surrounding or downstream resources—as well as to those
working or living on the farm or in neighboring areas. Furthermore, the concept of
sustainable agriculture extends intergenerationally, relating to passing on a conserved or
improved natural resource, biotic, and economic base instead of one which has been
depleted or polluted. Some important elements of sustainable agriculture
are permaculture, agroforestry, mixed farming, multiple cropping, and crop rotation.
Numerous sustainability standards and certification systems have been established in
recent years to meet development goals, thus offering consumer choices for sustainable
agriculture practices. Well-known food standards include organic, Rainforest Alliance, fair
trade, UTZ Certified, Bird Friendly, and the Common Code for the Coffee Community(4C).
Energy
Sustainable energy is the sustainable provision of energy that is clean and lasts for a long
period of time. Unlike the fossil fuel that most of the countries are using, renewable energy
only produces little or even no pollution. The most common types of renewable energy in
US are solar and wind energy, solar energy are commonly used on public parking meter,
street lights and the roof of buildings. On the other hand, wind energy is expanding quickly
in recent years, which generated 12,000 MW in 2013. The largest wind power station is in
Texas and followed up by California. Household energy consumption can also be improved
in a sustainable way, like using electronic with energy star
<https://en.wikipedia.org/wiki/Energy_Star> logo, conserving water and energy. Most of
California’s fossil fuel infrastructures are sited in or near low-income communities, and
have traditionally suffered the most from California’s fossil fuel energy system. These
communities are historically left out during the decision- making process, and often end up
with dirty power plants and other dirty energy projects that poison the air and harm the
area. These toxins are major contributors to significant health problems in the
communities. While renewable energy becomes more common, the government begins to
shut down some of the fossil fuel infrastructures in order to consume renewable energy
and provide a better social equity to the specific community.
Environment
29

30. Beyond ecology as the intersection of humans in the environment, environmental
sustainability concerns the natural environment and how it endures and remains diverse
and productive. Since Natural resources are derived from the environment, the state of air,
water, and the climate are of particular concern. The IPCC Fifth Assessment Report outlines
current knowledge about scientific, technical and socio-economic information concerning
climate change, and lists options for adaptation and mitigation.[30]
Environmental
sustainability requires society to design activities to meet human needs while preserving
the life support systems of the planet. This, for example, entails using water sustainably,
utilizing renewable energy, and sustainable material supplies (e.g. harvesting wood from
forests at a rate that maintains the biomass and biodiversity).
An "unsustainable situation" occurs when natural capital (the sum total of nature's
resources) is used up faster than it can be replenished. Sustainability requires that human
activity only uses nature's resources at a rate at which they can be replenished naturally.
Inherently the concept of sustainable development is intertwined with the concept of
carrying capacity. Theoretically, the long-term result of environmental degradation is the
inability to sustain human life. Such degradation on a global scale should imply an increase
in human death rate until population falls to what the degraded environment can support.
If the degradation continues beyond a certain tipping point or critical threshold it would
lead to eventual extinction for humanity.
Consumption of renewable
resources
State of environment Sustainability
More than nature's ability to
replenish
Environmental
degradation
Not sustainable
Equal to nature's ability to replenish
Environmental
equilibrium
Steady state economy
Less than nature's ability to
replenish
Environmental renewal
Environmentally
sustainable
Transportation
Some western countries and United States are making transportation more sustainable in
both long-term and short-term implementations. Since these countries are mostly highly
automobile-orientated area, the main transit that people use is personal vehicles.
Therefore, California is one of the highest greenhouse gases emission in the country. The
federal government has to come up with some plans to reduce the total number of vehicle
trips in order to lower greenhouse gases emission. Such as:
Improve public transit
30

31. - Larger coverage area in order to provide more mobility and accessibility, use new
technology to provide a more reliable and responsive public transportation network,
company providing ECO pass to employees.
Encourage walking and biking
-Wider pedestrian pathway, bike share station in commercial downtown, locate parking lot
far from the shopping center, limit on street parking, slower traffic lane in downtown area.
Increase the cost of car ownership and gas taxes
-Increase parking fees/ toll fees, encourage people to drive more fuel efficient vehicles.
-Social equity problem, poor people usually drive old cars that have low fuel efficiency.
However, government can use the extra revenue collected from taxes and tolls to improve
the public transportation and benefit the poor community.
Unit-II
Mineral Resources Classification
Mineral resource classification is the classification of mineral deposits based on their
geologic certainty and economic value.
Mineral deposits can be classified as:
• Mineral resources that are potentially valuable, and for which reasonable
prospects exist for eventual economic extraction.
• Mineral reserves or Ore reserves that are valuable and legally and economically
and technically feasible to extract
In common mining terminology, an "ore deposit" by definition must have an 'ore reserve',
and may or may not have additional 'resources'.
Classification, because it is an economic function, is governed by statutes, regulations and
industry best practice norms. There are several classification schemes worldwide, however
the Canadian CIM classification (see NI 43-101), the Australasian Joint Ore Reserves
Committee Code (JORC Code), the South African Code for the Reporting of Mineral
Resources and Mineral Reserves (SAMREC) and the “chessboard” classification scheme of
mineral deposits by H. G. Dill are the general standards.
Mineral Resources
A 'Mineral Resource' is a concentration or occurrence of material of intrinsic economic
interest in or on the earth's crust in such form, quality and quantity that there are
reasonable prospects for eventual economic extraction. Mineral Resources are further sub-
31

32. divided, in order of increasing geological confidence, into inferred, Indicated and measured
Categories.
Inferred Mineral Resource is that part of a mineral resource for which tonnage, grade and
mineral content can be estimated with a low level of confidence. It is inferred from
geological evidence and assumed but not verified geological/or grade continuity. It is based
on information gathered through appropriate techniques from location such as outcrops,
trenches, pits, workings and drill holes which may be of limited or uncertain quality and
reliability.
Indicated resources are simply economic mineral occurrences that have been sampled
(from locations such as outcrops, trenches, pits and drill holes) to a point where an
estimate has been made, at a reasonable level of confidence, of their contained metal,
grade, tonnage, shape, densities, physical characteristics.
Measured resources are indicated resources that have undergone enough further sampling
that a 'competent person' (defined by the norms of the relevant mining code; usually
a geologist) has declared them to be an acceptable estimate, at a high degree of confidence,
of the grade, tonnage, shape, densities, physical characteristics and mineral content of the
mineral occurrence.
Resources may also make up portions of a mineral deposit classified as a mineral reserve,
but:
• Have not been sufficiently drilled out to qualify for Reserve status; or
• Have yet to meet all criteria for Reserve status
Mineral Reserves/Ore Reserves
Mineral reserves are resources known to be economically feasible for extraction. Reserves
are either Probable Reserves or Proved Reserves.
A Probable Ore Reserve is the part of Indicated resources that can be mined in an
economically viable fashion, and in some circumstances, a Measured Mineral Resource. It
includes diluting material and allowances for losses which may occur when the material is
mined. A Probable Ore Reserve has a lower level of confidence than a Proved Ore Reserve
but is of sufficient quality to serve as the basis for decision on the development of deposit.
A Proved Ore Reserve is the part of Measured resources that can be mined in an
economically viable fashion. It includes diluting materials and allowances for losses which
occur when the material is mined.
A Proved Ore Reserve represents the highest confidence category of reserve estimate. The
style of mineralization or other factors could mean that Proved Ore Reserves are not
achievable in some deposits.
Generally the conversion of resources into reserves requires the application of various
modifying factors, including:
32

33. • mining and geological factors, such as knowledge of the geology of the deposit
sufficient that it is predictable and verifiable; extraction and mine plans based on ore
models; quantification of geotechnical risk—basically, managing the
geological faults, joints, and ground fractures so the mine does not collapse; and
consideration of technical risk—essentially, statistical and variography to ensure the
ore is sampled properly:
• metallurgical factors, including scrutiny of assay data to ensure accuracy of the
information supplied by the laboratory—required because ore reserves are bankable.
Essentially, once a deposit is elevated to reserve status, it is an economic entity and an
asset upon which loans and equity can be drawn—generally to pay for its extraction at
(hopefully) a profit;
• economic factors;
• environmental factors;
• marketing factors;
• legal factors;
• political factors; and
• social factors
Mineral Exploration
Mineral exploration is the process of finding ores (commercially viable concentrations of
minerals) to mine. Mineral exploration is a much more intensive, organized and
professional form of mineral prospecting and, though it frequently uses the services of
prospecting, the process of mineral exploration on the whole is much more involved.
Stages of Mineral Exploration
Mineral exploration methods vary at different stages of the process depending on size of
the area being explored, as well as the density and type of information sought. Aside from
extra planetary exploration, at the largest scale is a geological mineral Province (such as
the Eastern Goldfields Province of Western Australia), which may be sub-divided into
Regions. At the smaller scale are mineral Prospects, which may contain several mineral
Deposits.
Province scale - area selection
Area selection is a crucial step in professional mineral exploration. Selection of the best,
most prospective, area in a mineral field, geological region or terrain will assist in making it
not only possible to find ore deposits, but to find them easily, cheaply and quickly.
Area selection is based on applying the theories behind ore genesis, the knowledge of
known ore occurrences and the method of their formation, to known geological regions via
the study of geological maps, to determine potential areas where the particular class of ore
33

34. deposit being sought may exist. Often new styles of deposits may be found which reveal
opportunities to find look-alike deposit styles in rocks and terrains previously thought
barren, which may result in a process of pegging of leases in similar geological settings
based on this new model or methodology. This behavior is particularly well exemplified by
exploration for Olympic Dam style deposits, particularly in South Australia and worldwide
based on models of IOCG formation, which results in all coincident gravity and magnetic
anomalies in appropriate settings being pegged for exploration.
This process applies the disciplines of basin modeling, structural geology, geochronology,
petrology and a host of geophysical and geochemical disciplines to make predictions and
draw parallels between the known ore deposits and their physical form and the unknown
potential of finding a 'lookalike' within the area selected.
Area selection is also influenced by the commodity being sought; exploring for gold occurs
in a different manner and within different rocks and areas to exploration for oil or natural
gas or iron ore. Areas which are prospective for gold may not be prospective for other
metals and commodities.
Similarly, companies of different sizes (in terms of market capitalization and financial
strength) may look for different sized deposits, or deposits of a minimum size, depending
on their will and ability to finance construction. Often the major mining houses will not
look for deposits of less than a certain size class because small deposits will not meet their
criteria for an internal rate of return. This practice may result in larger mining companies
relinquishing control of smaller ore bodies they find, or may preclude them from entering a
terrain which is characterized by deposits of a particular type or style. For example, a
mining major would not look for a relatively small, high-cost Kambalda style nickel deposit
and would direct their efforts toward discovering a Mt Keith style deposit.
Often a company or consortium wishing to enter mineral exploration may conduct market
research to determine, if a resource in a particular commodity is found, whether or not the
resource will be worth mining based on projected commodity prices and demand growth.
This process may also inform upon the Area Selection process as noted above, where areas
with small-sized deposit styles will be ruled out based on likely economic returns should a
deposit be found. This occurs because often smaller deposits are more expensive to run,
and hence, carry greater risks of closure if commodity prices fall significantly.
Area selection may also be influenced by previous finds, a practice affectionately named
subsurface control or nearology, and may also be determined in part by financial and
taxation incentives and tariff systems of individual nations. The role of infrastructure may
also be crucial in area selection, because the ore must be brought to market and
infrastructure costs may render isolated ore uneconomic.
The ultimate result of an area selection process is the pegging or notification of exploration
licenses, known variously as tenements, claims or licenses.
Target generation - Regional Scale
The target generation phase involves investigations of the geology via mapping, geophysics
and conducting geochemical or intensive geophysical testing of the surface and subsurface
34

35. geology. In some cases, for instance in areas covered by soil, alluvium and platform cover,
drilling may be performed directly as a mechanism for generating targets.
Geophysical methods
Geophysical instruments play a large role in gathering geological data which is used in
mineral exploration. Instruments are used in geophysical surveys to check for variations
in gravity, magnetism, electromagnetism (resistivity of rocks) and a number of different
other variables in a certain area. The most effective and widespread method of gathering
geophysical data is via flying airborne geophysics.
Geiger counters and scintillometers are used to determine the amount of radioactivity. This
is particularly applicable to searching for uranium ore deposits but can also be of use in
detecting radiometric anomalies associated with metasomatism.
Airborne magnetometers are used to search for magnetic anomalies in the Earth's
magnetic field. The anomalies are an indication of concentrations of magnetic minerals
such as magnetite, pyrrhotite and ilmenite in the Earth's crust. It is often the case that such
magnetic anomalies are caused by mineralization events and associated metals.
Ground-based geophysical prospecting in the target selection stage is more limited, due to
the time and cost. The most widespread use of ground-based geophysics is electromagnetic
geophysics which detects conductive minerals such as sulfide minerals within more
resistive host rocks.
Ultraviolet lamps may cause certain minerals to fluoresce, and is a key tool in prospecting
for tungsten mineralization.
Remote sensing
Aerial photography is an important tool in assessing mineral exploration tenements, as it
gives the explorer orientation information - location of tracks, roads, fences, habitation, as
well as ability to at least qualitatively map outcrops and regolith systematics and
vegetation cover across a region. Aerial photography was first used post World War II and
was heavily adopted in the 1960s onwards.
Since the advent of cheap and declassified Landsat images in the late 1970s and early
1980s, mineral exploration has begun to use satellite imagery to map not only the visual
light spectrum over mineral exploration tenements, but spectra which are beyond the
visible.
Satellite based spectroscopes allow the modern mineral explorationist, in regions devoid of
cover and vegetation, to map minerals and alteration directly. Improvements in the
resolution of modern commercially based satellites has also improved the utility of satellite
imagery; for instance GeoEye satellite images can be generated with a 40 cm pixel size.
Geochemical methods
The primary role of geochemistry, here used to describe assaying or geological media, in
mineral exploration is to find an area anomalous in the commodity sought, or in elements
known to be associated with the type of mineralization sought.
35

36. Regional geochemical exploration has traditionally involved use of stream sediments to
target potentially mineralized catchments. Regional surveys may use low sampling
densities such as one sample per 100 square kilometres. Follow-up geochemical surveys
commonly use soils as the sampling media, possibly via the collection of a grid of samples
over the tenement or areas which are amenable to soil geochemistry. Areas which are
covered by transported soils, alluvium, colluvium or are disturbed too much by human
activity (roads, rail, farmland), may need to be drilled to a shallow depth in order to sample
undisturbed or unpolluted bedrock.
Once the geochemical analyses are returned, the data is investigated for anomalies (single
or multiple elements) that may be related to the presence of mineralization. The
geochemical anomaly is often field checked against the outcropping geology and, in modern
geochemistry, normalized against the regolith type and landform, to reduce the effects
of weathering, transported materials and landforms.
Geochemical anomalies may be spurious or related to low-grade or sub-grade
mineralization. In order to determine if this is the case, geochemical anomalies must
be drilled in order to test them for the existence of economic concentrations of
mineralization, or even to determine why they exist in the place they exist.
The presence of some chemical elements may indicate the presence of a certain mineral.
Chemical analysis of rocks and plants may indicate the presence of an underground
deposit. For instance elements like arsenic and antimony are associated with gold deposits
and hence, are example pathfinder elements. Tree buds can be sampled for pathfinder
elements in order to help locate deposits.
Resource evaluation
Resource evaluation is undertaken to quantify the grade and tonnage of a mineral
occurrence. This is achieved primarily by drilling to sample the prospective
horizon, lode or strata where the minerals of interest occur.
The ultimate aim is to generate a density of drilling sufficient to satisfy the economic and
statutory standards of an ore resource. Depending on the financial situation and size of the
deposit and the structure of the company, the level of detail required to generate this
resource and stage at which extraction can commence varies; for small partnerships and
private non-corporate enterprises a very low level of detail is required whereas for
corporations which require debt equity (loans) to buildcapital intensive
extraction infrastructure, the rigor necessary in resource estimation is far greater. For large
cash rich companies working on small ore bodies, they may work only to a level necessary
to satisfy their internal risk assessments before extraction commences.
Resource estimation may require pattern drilling on a set grid, and in the case of sulfide
minerals, will usually require some form of geophysics such as down-hole probing of drill
holes, to geophysically delineate ore body continuity within the ground.
The aim of resource evaluation is to expand the known size of the deposit and
mineralization. A scoping study is often carried out on the ore deposit during this stage to
determine if there may be enough ore at a sufficient grade to warrant extraction; if there is
not further resource evaluation drilling may be necessary. In other cases, several smaller
36