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Ellis D. Gordon

Publications and source records attributed to Ellis D. Gordon.

2 recordsLinked to original sources

Ground Water at Grant Village Site, Yellowstone National Park, Wyoming

On behalf of the National Park Service, the U.S. Geological Survey during the summer of 1959 made a study of ground-water conditions in the area of the Grant Village site, along the shore of the West Thumb of Yellowstone Lake, 1 to 2 miles south of the present facilities at West Thumb. The water supply for the present development at West Thumb is obtained from Duck Lake, but the quantity of water available from this source probably will be inadequate for the planned development at Grant Village. During the investigation, 11 auger holes were bored and 6 test wells were drilled. Aquifer tests by pumping and bailing methods were made at two of the test wells. All material penetrated in the auger holes and test wells is of Quaternary age except the welded tuff of possible Pliocene age that was penetrated in the lower part of test well 4. Small to moderate quantities of water were obtained from the test wells in the area. Test well 2 yielded 35 gpm (gallons per minute) at a temperature of nearly 100 deg F. Test well 6 yielded about 15 gpm at a temperature of 48 deg F. The yield of this well might be increased by perforation of additional sections of casing, followed by further development of the well. Water from the other four test wells was of inadequate quantity, too highly mineralized, or too warm to be effectively utilized. Most of the ground water sampled had high concentrations of silica and iron, and part of the water was excessively high in fluoride content. Otherwise, the ground water was of generally suitable quality for most uses. The most favorable area for obtaining water supplies from wells is near the lakeshore, where a large part of the water pumped would be ground-water flow diverted from its normal discharge into the lake. Moderate quantities of relatively cool water of fairly good quality may be available near the lakeshore between test wells 5 and 6 and immediately east of test well 6.

Water Supply Paper

Geology and ground-water resources of the Fort Berthold Indian Reservation, North Dakota, with a section on chemical quality of the ground water

The Fort Berthold Indian Reservation occupies about 1,000 square miles in west- central North Dakota. The Missouri and Little Missouri Rivers flow through the area and form part of its boundaries. Garrison Dam, which is under construction on the Missouri River 30 miles downstream from the east boundary of the reservation, will impound water in Garrison Reservoir and flood the valleys of both rivers throughout the area. The reservoir will divide the reservation into five parts, herein referred to as the eastern, northeastern, northern, western, and southern segments. Rock formations ranging in age from Paleocene to Recent are exposed. The Fort Union formation of Paleocene age underlies the entire reservation, and it crops out along the Missouri and Little Missouri Rivers. Relatively thin glacial till and outwash deposits of late Pleistocene age mantle much of the upland in all of the segments. The glacial de. posits commonly are less than 10 feet thick; in many places they consist only of scattered boulders on the bedrock surface. The major valleys have terrace deposits of Pleistocene and Recent age and alluvium of Recent age. The principal mineral resources of the reservation are lignite, sand, and gravel. The lignite beds range in thickness from a few inches to about 30 feet. At least four separate beds, which range in thickness from 4 feet to more than 7 feet, are mined locally. Although many mines will be flooded after Garrison Dam is completed, many suitable mine sites will remain above the proposed reservoir level. Sand and gravel deposits are found in glacial outwash and in stream-terrace deposits. On upland areas of the reservation ground water is available principally from the lignite and the associated fine- to medium-grained sandstone beds of the Fort Union formation. Few wells on the reservation are known to produce water from glacial material, although the recessional moraines are possible sources of shallow-water supplies. Small quantities of ground water are available from thin alluvial deposits in some places on the upland. Most wells in the valleys produce water from the alluvium or the terrace deposits. However, several wells penetrate the underlying Fort Union formation. A few flowing wells in the Missouri River valley near Elbowoods produce water from either the lower part of the Fort Union formation or from the Cannonball formation, also of Paleocene age. The chemical character of water from the Fort Union formation and the outwash and river gravels was determined from analyses of 39 samples from wells and springs. Water from bedrock may be either hard or soft, and it is moderately to highly mineralized. Water from the surficial deposits is uniformly hard, but it is less mineralized. Shallow wells in the eastern and northeastern segments produce water of good quality. Wells in these segments, and several springs in the western segment, could be used satisfactorily as domestic supplies. Spring water from lignite deposits on the reservation generally is colored and contains objectionable amounts of iron. Treatment of the water would improve its quality for domestic use. The filling of Garrison Reservoir will cause a rise of the water levels in wells that tap aquifers now discharging below the operating level of the reservoir. All the permeable strata below this level will become saturated, and ground-water bodies that are now separated will become hydraulically united. In addition to providing subsurface information, the drilling program of the U. S. Bureau of Indian Affairs provided wells for domestic and stock-water supplies. All test holes that tapped an adequate supply of potable water were reamed to a larger diameter, equipped with casing and well screen, and gravel-packed. The test-drilling program was completed in 1951; however, the drilling of domestic wells was continued under the supervision of the U. S. Geological Survey.

North Dakota