Reply #36: Did staff at Hope Creek lie to me? Maybe not...

[kristopher]

This is confirmation of the briefing they gave me. I won't deny that it may be dumbed down, but I don't think it is inaccurate. they used the natural reaction at Oklo to demonstrate their point. http://www.ocrwm.doe.gov/factsheets/doeymp0010.shtml

And I may be wrong, but aren't the properties we are concerned with in your "exploding a nuclear weapon" proof more a result of the degree to which the uranium is enriched. Nuclear power plants operate on slightly enriched uranium somewhere below 5% while bombs use highly enriched uranium of over 95%?

Doesn't that make the two processes radically different?

Are you asserting that if a heavy water moderated reactor loses it's water, the fission process will accelerate?


Neutron moderator
Heavy water is used in certain types of nuclear reactors where it acts as a neutron moderator to slow down neutrons so that they can react with the uranium in the reactor. The CANDU reactor uses this design. Light water also acts as a moderator but because light water absorbs more neutrons than heavy water, reactors using light water must use enriched uranium rather than natural uranium, otherwise criticality is impossible. The use of heavy water essentially increases the efficiency of the nuclear reaction.

Because of this, heavy water reactors will be more efficient at breeding plutonium (from uranium-238) or uranium-233 (from thorium-232) than a comparable light-water reactor, leading them to be of greater concern in regards to nuclear proliferation. The breeding and extraction of plutonium can be a relatively rapid and cheap route to building a nuclear weapon, as chemical separation of plutonium from fuel is easier than isotopic separation of U-235 from natural uranium. Heavy water moderated research reactors or specifically-built plutonium breeder reactors have been used for this purpose by most, if not all, states which possess nuclear weapons, although historically the first nuclear weapons were produced without it. (Pure carbon may be used as a moderator, even in unenriched uranium nuclear reactors. Thus, in the U.S., the first experimental atomic reactor (1942), as well as the Manhattan Project Hanford production reactors which produced the plutonium for the Trinity test and Fat Man bombs, all used pure carbon neutron moderators and functioned with neither enriched uranium nor heavy water).

There is no evidence that civilian heavy water power reactors, such as the CANDU or Atucha designs, have been used for military production of fissile materials. In states which do not already possess nuclear weapons, the nuclear material at these facilities is under IAEA safeguards to discourage any such diversion.

Due to its potential for use in nuclear weapons programs, the possession or import/export of large industrial quantities of heavy water are subject to government control in several countries. Suppliers of heavy water and heavy water production technology typically apply IAEA (International Atomic Energy Agency) administered safeguards and material accounting to heavy water. (In Australia, the Nuclear Non-Proliferation (Safeguards) Act 1987.) In the U.S. and Canada, non-industrial quantities of heavy water (i.e., in the gram to kg range) are routinely available through chemical supply dealers, and directly commercial companies such as the world's former major producer Ontario Hydro, without special license. Current (2006) cost of a kilogram of 99.98% reactor-purity heavy water, is about $600 to $700. Smaller quantities of reasonable purity (99.9%) may be purchased from chemical supply houses at prices of roughly $1 per gram.

http://en.wikipedia.org/wiki/Heavy_water