Abstract: This report consists of four parts, the first three being descriptions of investigations compiled in the period October 1st, 1953 to April 1st, 1954; the fourth part is a summary of progress of the research based on our entire investigations completed prior to April 1st, 1954. The first part comprises a set of preliminary experiments investigating the mineral composition of the sandstones in thin sections, in an attempt to differentiate barren from ore-bearing sandstones. It appears that there are more rock-fragments and particularly more volcanic rock fragments in the ore zone (zone 4, Well C, Bull Canyon). In addition, silica cement appears to be associated with ore and carbonate cement with barren sediments. The second part details the investigation of the mudstones of the Bull Canyon Wells . A mixed layer lattice "illite" and a kaolin mineral are the most prominent in "normal" mudstones. Dye tests suggest there are differences between the clay minerals in the sandstone matrix of the ore zone and barren zone. In addition, the mudstone zones appear to differ in the response to the dye tests. The third part of the report details the bulk density determinations for cores from well B. The results confirm …

This report evaluates potential impacts to public health or the environment resulting from groundwater contamination at the former uranium mill processing site. The tailings and other contaminated material at this site are being placed in an off-site disposal cell by the US Department of Energy`s (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project. Currently, the UMTRA Project is evaluating groundwater contamination. This is the second risk assessment of groundwater contamination at this site. The first risk assessment was performed primarily to evaluate existing domestic wells to determine the potential for immediate human health and environmental impacts. This risk assessment evaluates the most contaminated groundwater that flows beneath the processing site towards the Gunnison River. The monitor wells that have consistently shown the highest concentration of most contaminants are used in this risk assessment. This risk assessment will be used in conjunction with additional activities and documents to assist in determining what remedial action is needed for contaminated groundwater at the site after the tailings are relocated. This risk assessment follows an approach outlined by the US Environmental Protection Agency (EPA). The first step is to evaluate groundwater data collected from monitor wells at the site. Evaluation of these data showed …

The following report presents a preliminary account of the geology and economic aspects of the uranium deposits in the Eureka Gulch area.

Report discussing nine radioactive mine dumps in the Eureka Gulch area of the Central City District of Gilpin County, Colorado, that were discovered between 1951 and 1953.

From introduction: The compilation of the tectonic map of northern Colorado and northeastern Utah (area h, fig. 2) was done by the U. S. Geological Survey on behalf of the Division of Raw Materials of the U. S. Atomic Energy Commission. Structures shown on the map have been obtained from published geologic maps, and from unpublished data supplied by government agencies, private companies, and independent geologists. The various structures of the Foreland can be divided into three large classes to show the relation of uranium deposits to the structural pattern.

A report characterizing known uranium occurrences in the Montrose Quadrangle and to find other areas in the quadrangle with similar characteristics

Second volume of a report documenting a high-sensitivity airborne radiometric and magnetic survey of the Leadville quadrangle including a detailed geologic summary, interpretation report, standard deviation maps, pseudo-contour maps, interpretation maps, flight line and geologic base map, and individual corrected profiles.

From introduction: This report relates to the first of the above objectives by describing stream quality in the Yampa River basin through 1976, with particular emphasis on conditions from August 1975 through September 1976. The content of this report is, at times, relatively technical. This is intentional. The report is aimed not at planners and decision makers but rather at those persons assigned the task of having to design, implement, and interpret a river basin assessment. The techniques and procedures used to determine ambient stream quality in the Yampa River basin have been presented in detail so that their applicability to other river basins can be determined. For the planner and decision maker, the results presented in this report are summarized in less technical terms in phase-l (Steele and others, 1979) and phase-ll summary reports.