Date of Award


Document Type


Degree Name

Master of Science (MS)



First Advisor

A.M. Cvancara


Increased lignite development around the small towns of Beulah and Hazen, North Dakota, will cause rapid growth and necessitate the develop ment of new subdivisions and expansion of present sewage disposal facili ties. A detailed geologic study of a 9 0-square mile area surrounding the two towns was undertaken to provide information valuable to those concerned with proper management of this growth. A surface and near-surface materials map was prepared at a scale of 1:24, 000 showing relative depths and thicknesses of a maximum of three earth materials to a depth of 9 m. Eleven units were mapped at the surface, and six units in the subsurface. Four cross-sections, and four interpretive land-use maps at a scale of 1:63, 000 were also compiled, including a hazard map and three suitability maps for sanitary landfills, septic tank systems, and general construction. A map showing buried valleys, diversion trenches, and meltwater channels was also compiled at a scale of 1:63, 000.

The Sentinel Butte Formation (Paleocene) is the only preglacial unit at the surface or within the near-surface. The late Cenozoic Charging Eagle Formation is possibly present in a few places. The Napoleon "till" of the Coleharbor Formation {Pleistocene} is probably the only pebble-loam exposed at the surface. Older pebble-loam beds are apparently present in many buried valleys. Postglacial sediments are within the Oahe Formation.

Evidence from limited exposures indicates deposition of the Sentinel -x Butte Formation in a predominantly fluvial environment by low sinuosity streams. Several of these streams may have been braided as is the modem Brahmaputra in the Bengal Basin.

A possible late Wisconsinan age for the Napoleon drift is suggested from evidence associated with the K.rem moraine. Buried valleys north and northeast of Beulah, and the Renner trench were recognized by drilling and sags in the topography. At least three fills reveal multi-stage origins for diversion trenches. The second fill is believed to have been laid down in an ice-dammed lake. The third fill was deposited as a wall-to-wall fill between Beulah and Hazen, and within a newly cut, ice marginal valley east of Hazen.

Flooding, mine sinkhole subsidence, slump and sliding, and drifting sand are existing or potential hazards. Flooding is the most serious as other hazards are removed from pre sent population centers. Regional climate is favorable for leachate containment in sanitary landfills, but many areas are inadequate due to steep slopes, high permeability, or potential flooding. The proper location of septic tank systems is governed chiefly by permeability and depth to the water table. Many good sites are available, provided areas prone to flooding and areas of steep slopes are avoided, and proper design and spacing of the septic system is employed. The best site for a new sewage lagoon for Beulah is to the east on the Knife River floodplain, but special engineering precautions will be required to prevent water pollution. The pre sent site of the sewage lagoon northeast of Hazen is the most suitable. Most favorable construction sites are to the north of both Beulah and Hazen. Further development on the flood plain would be ill-advised due to occasional flooding.

Meyer (325224 kB)

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