Abstract: A low-level airborne radioactivity survey of parts of Beaverhead and Madison Counties in southwestern Montana was undertaken from June 6 to October 14, 1955. Flying centered around the Ruby Range-Sweetwater Basin area and concentrated on the Precambrian metamorphic complex and Tertiary lake-bed sediments. No commercial uranium deposits were discovered, and no extensions were found of the few known small occurrences. Five areas of high background detected through the survey were investigated on the ground.

Introduction: The experimental work reported here was undertaken as a part of the over-all design and development program for a nuclear reactor pressure vessel.

The purpose of this report is to describe the shielding calculations and techniques used in sizing the MMSR primary shield, the results obtained, and the resulting shield thicknesses. The present report covers many of the items scheduled for presentation in the final MMSR shield design report to be issued in November of 1958. The primary shield in the MMSR consists of the reflector, thermal shields, pressure vessel wall, a 33" water annulus and a layer of lead shielding at the exterior of the primary shield tank vary from 3" to 1" in thickness.

Technical report was prepared by the Health and Safety Laboratory (HASL) with the objective of presenting a current picture of the Strontium Program. Abstract: Strontium 90 levels in fallout, milk, canned fish and tap water are summarized for data available up to April 5, 1958. Original data submitted during the month of March are included as an appendix. Data are presented to show the amount of Strontium 90 in fallout at sampling stations within and outside the United States.

Abstract: An analysis and a summary are.given of the radioactivity buildup program at the Army Package Power Reactor during the last nine months. · Due to the wide fluctuation of water and crud results, only general interpretations can be made with this data. Metal test coupon data indicate a substantially greater buildup on Croloy 16-1 metal than on Type 304 stainless steel. Coupled with the decreased ability to remove the radioactivity buildup on Croloy 16-1 by conventional descaling techniques, the implication is that this metal might pose a serious problem for use as steam generator material. It was emphasized, however, that results to date ae only preliminary and extensive additional experimentation would be required to reach more definite conclusions.

Engineering study on underground construction of nuclear power reactors.

Quarterly technical report discussing progress and activities of the Liquid Metal Fuel Reactor Experiment.

Report describing the preliminary design of a 55,000 kW prototype of a natural uranium nuclear power plant for the United States Atomic Energy Commission. Testing of the design and potential requirements for operating the plant are included.

Report containing "a discussion of the feasibility design and cost estimates for a gas cooled, natural uranium, graphite moderated power plant optimized for minimum power cost" (p. 3).

Report that "contains a discussion of the feasibility study and cost estimates for a gas cooled, partial enriched uranium, graphite moderated power plant" (p. 3).

Report that contains "a preliminary design and feasibility studies of gas cooled, graphite moderated, nuclear power plants" (p. 1).