Western United States resources

At the present rate of world phosphate rock consumption (150 x 10 t/yr), the total world reserve (Table 14) is sufficient for about 200 years, and the resource would be sufficient for nearly 900 years. At expected increased rates of consumption, the reserves and resources are adequate for at least 150 years and 700 years, respectively. At projected rates of consumption, the high grade reserves in Florida probably will be exhausted by the year 2000. Rock production from the Florida reserve presentiy constitutes about 80% of all United States production and about one-third of world production (106). This rate of depletion is causing increased interest in western United States reserves which represent nearly 80% of present U.S. total reserves. 

Demonstrated reserve quantities are estabUshed by measurements including drillings surface sampling, etc. Inferred reserves are those derived from geological survey information, not by measurement of the extent of the particular reserve. Not included herein are identified marginal and speculative resources, such as the oil-field and geothermal brines and lithium-hearing clays. These latter reserves are speculative as to extent, not existence. Total undiscovered clays in the western United States are speculatively estimated at 15 x 10 t lithium (16). More detailed Hsts of reserves are also available (15,17). 

Domestic. Estimates of U.S. uranium resources for reasonably assured resources, estimated additional resources, and speculative resources at costs of 80, 130, and 260/kg of uranium are given in Table 1 (18). These estimates include only conventional uranium resources, which principally include sandstone deposits of the Colorado Plateaus, the Wyoming basins, and the Gulf Coastal Plain of Texas. Marine phosphorite deposits in central Elorida, the western United States, and other areas contain low grade uranium having 30—150 ppm U that can be recovered as a by-product from wet-process phosphoric acid. Because of relatively low uranium prices, on the order of 20.67/kg U (19), in situ leach and by-product plants accounted for 76% of total uranium production in 1992 (20). 

In recent years, efforts have been undertaken to conserve water due to the growing demand for a limited resource. As a result, water reuse is being employed, especially in the Western United States. Water reuse is when wastewater generated from a community is reclaimed for a beneficial use such as irrigation for ornamental or agricultural crops, decorative water features, industrial application and with advanced treatment potable water. The use of reclaimed water may expose the public to chemical and microbial contamination from the wastewater stream. Therefore, for each type of beneficial reuse, treatment standards are being established to protect public health. 

Hot Dry Rock - A geothermal energy resource that consists of high temperature rocks above 300 F (150 C) that may be fractured and have little or no water. To extract the heat, the rock must first be fractured, then water is injected into the rock and pumped out to extract the heat. In the western United States, as much as 95,000 square miles (246,050 square km) have hot dry rock potential. 

The grade of oil shale can be determined by measuring the yield of oil of a shale sample in a laboratory retort. This is perhaps the most common type of analysis that is currently used to evaluate an oil shale resource. The method commonly used in the United States is the modified Fischer assay, first developed in Germany and then adapted by the U.S. Bureau of Mines for analyzing oil shale of the Green River formation in the western United States (Stanfield and Frost, 1949). The technique was subsequently standardized as the American Society for Testing and Materials (ASTM) Method D-3904-80 (ASTM, 1984). Some laboratories have further modified the Fischer assay method to better evaluate different types of oil shale and different methods of oil-shale processing. 

Coal, tar, and heavy oil fuel reserves are widely distributed throughout the world. In the Western hemisphere, Canada has large tar sand, bitumen (very heavy cmde oil), and coal deposits. The United States has very large reserves of coal and shale. Coal comprises ca 85% of the U.S. recoverable fossil energy reserves (6). Venezuela has an enormous bitumen deposit and Brazil has significant oil shale (qv) reserves. Coal is also found in Brazil, Colombia, Mexico, and Pern. Worldwide, the total resource base of these reserves is immense and may constitute >90% of the hydrocarbon resources in place (see... 

North America.. In the United States, lignite deposits are located in the northern Great Plains and in the Gulf states. Subbituminous coal is found along the Rocky Mountains. The western half of North Dakota has about 74% of the nation s resources, Montana 23%, Texas 2%, and Alabama and South Dakota about 0.5% each. The lignite resources to 914 m represent 28% of the total toimage of all coal deposits in the United States. The lower cost and low sulfur content have contributed to rapid growth in production. 

Other Constituents of Stream Water. The records reported ia Refs. 21 and 22 were obtaiaed for the primary purpose of evaluating the suitabihty of surface water resources of the United States for utilization by iadustry and for irrigation of agricultural lands ia the western part of the country. These stream waters also provide pubHc water suppHes for many municipahties. Evaluations of water quaUty for the latter purpose emphasize constituents that were not given detailed consideration ia Refs. 21 and 22 summaries, although there are references ia Ref. 21 to work done ia various state health laboratories and municipal treatment plants. 

Almost two-thirds of the world s copper resources are porphyry deposits. The term porphyry is generally appUed to a type of disseminated copper deposit that is hydrothermal in origin and characterized by a large proportion of minerals uniformly distributed as disseminations or in fractures and small veins. Copper contents are generally 1% or less. The most extensive porphyry deposits are located in western Canada, the southwestern United States, Mexico, and western South America. In addition to the porphyrys, there are large bedded copper deposits in Germany, Poland, the CIS, AustraUa, and central Africa. 

The largest untapped fossil fuel resource in the United States is the oil bearing shales in the western part of the country and the black shales in the east. The oil shale resource concentrated in three western states is estimated to be equivalent to more than two trillion barrels of crude oil. An additional two trillion barrels of oil exists in the lean deposits of the Eastern U.S. 

Hein, J.R., Morgenson, L.A., Clague, D.A. and Koski, R.A., 1987. Cobalt-rich ferromanganese crusts from the exclusive economic zone of the United States and nodules from the oceanic Pacific. In Scholl, D.W., Grantz, A. and Vedder, J.G (eds). Geology and resource potential of the continental margin of western North America and the adjacent oceans-Beaufort Sea to Baja California. Circum-Pacific Council for Energy and Mineral Recources, Earth Science Series, Houston, Texas, pp. 753-771. 

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