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<br />002887
<br />
<br />Mining, Conversion, and Processing Alternatives
<br />
<br />Coal mining, conversion, and processing alternatives will be limited to
<br />technologies potentially appl icable to the Yampa River basin, It will be
<br />essential to determine the Impacts of these alternatives on the quantity and
<br />quality of the Yampa River and its tributaries, This will require an estimate
<br />of the types and amounts of residuals generated by coal mining and associated
<br />activities, Residuals will vary with the size and location of mining activi-
<br />ties. Models exist, or can be adapted, to estimate the impacts of different-
<br />sized processes (N. C. Matalas, written commun., 1976). For the res idua1s-
<br />management analysis, the additional effort required to model all the many pro-
<br />posals does not seem justified. However, for the basin assessment, the use of
<br />site-specific information will be necessary, particularly for the mining pro-
<br />cess where projected coal-mining levels are documented (U,S. Bureau of Land
<br />Management and U,S, Geological Survey, written commun., 1976).
<br />
<br />For the residuals-management analysis, coal mining Is assumed to occur
<br />from an even integer number of strip mines each producing 3.125x106 tons
<br />(2.84x106 t) per year (N. C. Matalas, written commun., 1976), This assumption
<br />is based on the estimated scale of coal mines in northwestern Colorado (U.S.
<br />Bureau of Land Management and U.S, Geological Survey, written commun, , 1976).
<br />Thus, two hypothetical mines, each supplying coal of the type found in the
<br />Williams Fork Mountains in the Yampa River basin, will supply the 6,25x106
<br />tons (5.68x106 t) per year required for either a standard-sized coal-gasifi-
<br />cation plant of 250x106 cubic feet (71x106 m3) per day (Forney and McGee,
<br />1972) or a standard 2,000-megawatt electric-power plant which will operate
<br />under the highest levels of envi ronmental control (N. C, Mata1as, written
<br />commun., 1976). Under less strIct environmental controls, the excess coal
<br />will be assumed to be marketed for out-of-basin consumption. Each plant wil I
<br />be assumed to be supplied with one-half of the coal required from a mine lo-
<br />cated next to the plant with transportation of the other one-half of the re-
<br />quired coal from a neighboring mine.
<br />
<br />It is assumed that possible coal-gasification plants for the Yampa River
<br />basin will use the SYNTHANE conversion process (Forney and McGee, 1972) and be
<br />operated within the ranges of temperatures and pressures for which data col-
<br />lected under controlled laboratory conditions prior to construction of pilot-
<br />scale plant facilities have been obtained. It is assumed that the electric
<br />power-generating plants will use conversion processes and operating procedures
<br />the same as the present state of technology, It also is assumed that the pow-
<br />er-generating capacities of the electric power-generating plants will be ap-
<br />proximately 1,200 megawatts. The validity of the last assumption is supported
<br />by electrIc-power plants at Craig and Hayden being expanded and under construc-
<br />tion, respectively, Sometime near 1982, proposed power-generating capacities
<br />at the Craig plant will be 1,070 megawatts; at the Hayden plant, 1,330 mega-
<br />watts (U.S. Bureau of Mines and U.S. Environmental Protection Agency, 1975),
<br />Although the power-generating capacities of the electric-power plants are fix-
<br />ed for the residuals-management analysis, computer programs that define the
<br />impact of plants of different power-generating capacities will have to be mod-
<br />i fied.
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