This document consists of information about the cooling systems of Hanford Production Reactors. It is the purpose of this letter, written May 8, 1961, to update recommendations of high-tank temperatures required to insure acceptable high-tank backup support. It does not appear practicable to relate the somewhat arbitrary standards of reference for backup support to process operating limits, i.e., reactor power levels, particularly as a mandatory requirement. For this reason, we have chosen at this time not to include these limits as a process standards` requirement. Considerable emphasis should be placed on insuring that the high-tank backup support be maintained in the maximum practical manner. Tables are attached showing high-tank temperature versus reactor power level relationships to satisfy the intent of our backup criteria and, through compliance, will insure that high-tank flow rates will be adequate during a reactor emergency following the loss of electrical power and steam.

It was stated by HAPO representatives at meetings held in Washington and Savannah River on May 1st and 2nd, that roughly 200 kgs of Pu of 18 percent Pu-240 could be furnished by July 1, 1965 to Savannah River for their proposed Cm-244 program. The Pu would be produced by irradiating .2 percent U-235 depleted uranium for a period of roughly ten months. The reactivity required for the depleted uranium irradiation would be furnished by .947 percent U-235 enriched uranium. Nine tons of slightly enriched uranium would be required for each ton of depleted uranium during its complete irradiation. To implement this program to deliver Pu of high isotope content by July 1, 1965 will require immediate internal program approvals and appropriate implementation steps. These steps will include design and specification of the depleted uranium ordering appropriate quantities of E and depleted; determining and ordering appropriate canning components; and determining reactor loading patterns. Special attention will ultimately be required in the separation of the reactor products. The additional quantities of E-metal required for the loading will probably necessitate early installation of the annular type Purex dissolver.

While the safety status of the Richland facilities has in the past been deemed adequate all aspects of nuclear technology have progressed and evolved including standards of nuclear safety. During FY 1968 the nuclear safety R&D efforts continued along the lines and at about the schedule predicted at the beginning of the year. Hence, the safety problems to be studied have been identified and the program seems well-defined. While some program modifications and changes in emphasis are to be expected, the five-year outline shown here is considered to be a reasonable representation of the safety work of highest priority to be studied.

Nine inch long aluminum clad Li-Al alloy target elements contained in 35 miI wall Zr-2 cans are authorized for irradiation in KER-1 and KER- 2 for up to 150 equilibrium operating days. The Li-Al elements will be irradiated in 1.9 inch OD, 1.5 inch ID Zr-2 flow distributing sleeves. Normal N inner fuel elements in Zr-2 sleeves will included in the tube loadings to provide sufficient heat to maintain the loop at the desired operating temperature.

This report gives the status of production test control tube loadings in reactor process tubes containing significant amounts of SS materials. These data are given in table form. For further description of column headings and the current discharge goal exposure plan refer to Document DUN-1048.