This was weapons grade uranium, U235. Not to mention that plutonium was also found at this site<p><a href="http:&#x2F;&#x2F;www.npolicy.org&#x2F;article_file&#x2F;Revisiting_the_NUMEC.pdf" rel="nofollow">http:&#x2F;&#x2F;www.npolicy.org&#x2F;article_file&#x2F;Revisiting_the_NUMEC.pdf</a>