, ▁and ▁K ▁React ors ▁followed ▁in ▁ 1 9 5 4 , ▁and ▁the ▁first ▁ir rad i ated ▁fuel ▁was ▁dis charg ed . ▁F ▁C any on , ▁the ▁world ' s ▁first ▁oper ational ▁full - scale ▁P URE X ▁separation ▁plant , ▁began ▁radio active ▁operations ▁on ▁ 4 ▁November . ▁P URE X ▁( Pl ut on ium ▁and ▁U ran ium ▁EX tra ction ) ▁extracted ▁plut on ium ▁and ▁u ran ium ▁products ▁from ▁materials ▁ir rad i ated ▁in ▁the ▁react ors . ▁ ▁In ▁ 1 9 5 5 , ▁C ▁Re actor ▁went ▁critical . ▁The ▁first ▁plut on ium ▁ship ment ▁left ▁the ▁site . ▁H ▁C any on , ▁a ▁chemical ▁separation ▁facility , ▁began ▁radio active ▁operations . ▁P erman ent ▁tr it ium ▁facilities ▁became ▁oper ational ▁and ▁the ▁first ▁ship ment ▁of ▁tr it ium ▁to ▁the ▁At omic ▁Energy ▁Commission ▁( A EC ) ▁was ▁made . ▁In ▁ 1 9 5 6 , ▁construction ▁of ▁the ▁basic ▁plant ▁was ▁complete . ▁ ▁Nobel ▁Prize ▁The ▁neut r ino ▁was ▁discovered ▁by ▁Fred ▁Re ines ▁and ▁C ly de ▁Cow an ▁using ▁the ▁flux ▁from ▁P ▁Re actor , ▁with ▁confirm ation ▁published ▁in ▁the ▁ 2 0 ▁July ▁ 1 9 5 6 ▁issue ▁of ▁Science . ▁Re ines ▁was ▁awarded ▁the ▁ 1 9 9 5 ▁Physics ▁Nobel ▁Prize ; ▁Cow an ▁had ▁already ▁died . ▁ ▁In ▁ 1 9 6 1 ,