The very strong flux gradient in the MTR reflector might be thought to be some cause of worry. However, this gradient will be minimized by the presence of the large block of aluminum, which, because of its small effect on neutrons, will tend to flatten the neutron flux in its vicinity. Advantage should be taken of the shape of the test facility by placing the water hole corner closest to the MTR core. This placement should take best advantage of the flattening potentialities of the slowing-down flux from the test slugs, by placing the nearest (beryllium) moderator on the low flux side of the assembly.