▁effects ▁and ▁other ▁physics ▁parameters ▁needed ▁for ▁re actor ▁development ▁at ▁Ch alk ▁River ▁Labor ator ies , ▁including ▁fuel ▁l att ices ▁for ▁the ▁NR U ▁re actor ▁situated ▁next ▁door . ▁ ▁Z E EP ▁was ▁one ▁of ▁the ▁world ' s ▁first ▁heavy ▁water ▁react ors , ▁and ▁it ▁was ▁also ▁designed ▁to ▁use ▁natural ▁( un en rich ed ) ▁u ran ium ; ▁a ▁feature ▁carried ▁through ▁to ▁the ▁C AND U ▁design . ▁U ran ium ▁en rich ment ▁is ▁a ▁complex ▁and ▁expensive ▁process ; ▁thus , ▁the ▁ability ▁to ▁use ▁un en rich ed ▁u ran ium ▁gave ▁Z E EP ▁and ▁its ▁descend ants ▁a ▁number ▁of ▁distinct ▁advantages . ▁ ▁Z E EP ▁continued ▁to ▁be ▁used ▁for ▁basic ▁research ▁until ▁ 1 9 7 0 . ▁ ▁It ▁was ▁de comm ission ed ▁in ▁ 1 9 7 3 ▁and ▁dis m ant led ▁in ▁ 1 9 9 7 . ▁In ▁ 1 9 6 6 ▁Z E EP ▁was ▁designated ▁a ▁historic ▁site ▁by ▁Ontario , ▁and ▁comm emor ated ▁with ▁an ▁historic ▁pla que . ▁ ▁Both ▁this ▁pla que ▁and ▁Z E EP ▁itself ▁are ▁now ▁on ▁display ▁at ▁the ▁Canada ▁Science ▁and ▁Technology ▁Museum ▁in ▁Ott awa , ▁Canada . ▁ ▁See ▁also ▁ ▁Science ▁and ▁technology ▁in ▁Canada ▁C AND U ▁re actor ▁He avy ▁water ▁re actor ▁A E CL ▁List ▁of ▁nuclear ▁react ors ▁ ▁References ▁ ▁External ▁links ▁N RC ▁Archives ▁Phot ograph