Sanderson & Porter have carried out a series of studies over the last four years which indicate that the pebble-bed reactor way be an attractive way to obtain low-cost power. At the request of the Atomic Energy Commission, two design studies have been carried out on this concept at the Oak Ridge National Laboratory. The first of these a preliminary design of a 10-Mw(t) reactor experiment, the PRRE, was initiated September 10, and a report on the study was issued November 1960. The second phase of the work, a conceptual design study of a 330-Mw (e) central station, was initiated November 1, and is the subject of this report.

This report follows a series of tests run to determine the shielding properties of beryllium oxide, conducted at the Battelle Lid-Tank Shielding Facility. Neutron and gamma penetrations through and behind beryllium oxide were measured.

A carrier containing 138.99 liters of solution, uranium concentration 202.04 g/liter with an isotopic concentration of 97.3% U-233, was prepared for shipment. The total uranium was 28,062 +/- 60 g (95% confidence level) and the U-233, 27,305 +/- 66 g (95% confidence level).

Quarterly report documenting progress on a project to determine an improved zirconium alloy for service in superheated water and steam. This report describes the results of approximately 75 compositions that were prepared prior, and presently are being arc-melted and fabricated into corrosion specimens, continuing the investigations of the effect of zirconium purity and heat treatment on corrosion and resistance.

The following report is one of a series of quarterly reports following the progress and development of improved zirconium alloys for service in superheated water and steam. This report covers the period between January 1 to March 31, 1961.