Rapid excavation: significance, needs, opportunities. (1968) / Chapter Skim
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Significance
Significance
Pages 7-15
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From page 7... ...
Moreover, as the GNP and the average individual and family income continue to rise, the proportion of the total income available for discretionary expenditures increases more rapidly and entices an ever-growing number of Americans to invest a higher proportion of their income in improvement of the environment in which they live. Two aspects of this concern deserve attention here: urbanization and natural resource conservation.
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From page 8... ...
It is widely, but enoneously, assumed that the oidy practical answer to increasing density and congestion within the urban environment is to spread out -- to expand horizontally. Consequently, the urban environment that is given consideration is primarily a shallow band extending a few dozen feet downward and a few hundred feet upward from the surface.
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From page 9... ...
In short, all thinking about future cities, whether by urban experts or by the public at large, takes place within a cultural context, the most pronounced phase of which is lack of awareness and appUcation of technological capability. In conceiving potential solutions to urban problems, the urban expert and the general public tend to assume certain technological constraints, often with little knowledge of what these constraints actually mean or how inexpensively they might be relaxed.
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From page 10... ...
Highest on the list of these constraints are the technological ones, particularly in r ^ r d to defining subterranean conditions to be met and determining design solutions to be implemented. The current imprecision attending this definition and determination frequently results either in improper rqection of subsurface facilities on the basis of infeasibility or in excessive cost of completed facilities.
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From page 11... ...
This beclouding of otherwise objective evaluations frequently results in rejection of subsurface faciUties. Another factor that severely influences plaiuiing-design consideration of subsurface facilities, partteularly public-works facilities, is time.
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From page 12... ...
In some cases, the natural environment can be restored to an acceptable state through sufficient investment, though this investment often exceeds the initial benefits from the despoiling of the environment. For this reason the federal government and most state govenmients have developed a variety of programs to limit the arena within which market costs are the sole arbiter of demand for and method of mining natural resources.
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From page 13... ...
As a consequence, there has been a dramatic emphasis in the United States on surfacemining methods, such that some 8S percent of our mineral production today is derived from this form of operation. This emphasis, due to technological change, has been one of the major factors responsible for the ability of the mining industry tofrustratecontinually the effect of diminishing returns as the higher-grade surface deposits have been exhausted.
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From page 14... ...
These deposits are offsets to future mineral trade deficits. A striking example of such a large-scale development is the immense oil-share reserve underlying Colorado, Wyoming, and Utah; a marked technological advance in mining systems could very well make underground mining of up to 200,000 tons per day commercially feasible.
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From page 15... ...
with the private sector in new technology investment, or to stimulate this investment either when there are large returns to the public or when heavy constraints are to be placed on private development.
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