▁The ▁ ▁village ▁has ▁a ▁population ▁( 2 0 1 8 ) ▁of ▁ 5 4 9 ▁and ▁a ▁population ▁density ▁of ▁. ▁ ▁References ▁ ▁Category : Ge ography ▁of ▁Tr ond heim ▁Category : V ill ages ▁in ▁Tr ø nd el ag <0x0A> </s> ▁The ▁Z E EP ▁( Zero ▁Energy ▁Ex perimental ▁P ile ) ▁re actor ▁was ▁a ▁nuclear ▁re actor ▁built ▁at ▁the ▁Ch alk ▁River ▁Labor ator ies ▁near ▁Ch alk ▁River , ▁Ontario , ▁Canada ▁( which ▁su pers eded ▁the ▁Montreal ▁Labor atory ▁for ▁nuclear ▁research ▁in ▁Canada ). ▁ ▁Z E EP ▁first ▁went ▁critical ▁at ▁ 1 5 : 4 5 ▁on ▁September ▁ 5 , ▁ 1 9 4 5 . ▁ ▁Z E EP ' s ▁was ▁the ▁first ▁oper ational ▁nuclear ▁re actor ▁outside ▁the ▁United ▁States . ▁ ▁The ▁re actor ▁was ▁designed ▁by ▁Canadian , ▁British ▁and ▁French ▁scient ists ▁as ▁a ▁part ▁of ▁an ▁effort ▁to ▁produce ▁plut on ium ▁for ▁nuclear ▁weapons ▁during ▁World ▁War ▁II . ▁ ▁It ▁was ▁developed ▁while ▁the ▁Montreal ▁Labor atory ▁and ▁Ch alk ▁River ▁Labor ator ies ▁research ▁facility ▁were ▁under ▁the ▁super vision ▁of ▁the ▁National ▁Research ▁Council ▁of ▁Canada ▁( N RC ). ▁ ▁Z E EP ▁was ▁instrument al ▁in ▁the ▁development ▁of ▁the ▁NR X ▁and ▁NR U ▁react ors , ▁which ▁led ▁to ▁the ▁development ▁of ▁the ▁successful ▁C AND U ▁re actor . ▁ ▁Z E EP ▁was ▁used ▁to ▁test ▁react ivity