TO: Dr. Clifford K. Beck
FROM: A. C. Menius, Jr. and Raymond L. Murray
SUBJECT: The estimated requirements on Barytes are given below:

According to Professor Bramer's calculations,^a1 73% of the weight
of the concrete is Barytes. Since the total reactor shield with is
approximately 200 tons, the total Barytes needed is 146 tons.

^a1Specifications for Nuclear Reactor Shield.