▁$ 1 5 . 8 ▁million ▁on ▁the ▁pre lim inary ▁phase ▁of ▁the ▁West ▁Che y enne ▁Super fund ▁Site ▁over ▁the ▁past ▁de cade , ▁installing ▁monitoring ▁well s , ▁containing ▁and ▁pass ively ▁tre ating ▁water , ▁and ▁a ▁feas ibility ▁study ▁on ▁installing ▁" inter ceptor ▁well s ". ▁A ▁Rest oration ▁Ad vis ory ▁Board ▁is ▁established . ▁The ▁extent ▁of ▁the ▁under ground ▁T CE ▁pl ume ▁is ▁unknown ; ▁data ▁analysis ▁due ▁to ▁be ▁completed ▁ 2 0 1 5 ▁will ▁inform ▁about ▁its ▁size . ▁The ▁Army ▁Corps ▁of ▁Engine ers , ▁who ▁built ▁the ▁IC B M ▁launch ▁site ▁in ▁the ▁ 1 9 5 0 s , ▁has ▁been ▁involved ▁in ▁investigation ▁and ▁clean ▁up ▁since ▁ 1 9 8 9 ; ▁the ▁project ▁manager ▁for ▁the ▁Corps ▁estimated ▁in ▁ 2 0 1 4 ▁" it ▁will ▁likely ▁be ▁a ▁more ▁than ▁ 1 0 0 - ▁or ▁ 2 0 0 - year ▁effort ▁to ▁actually ▁remove ▁the ▁chemical s ▁from ▁the ▁ground water ". ▁Atlas ▁miss ile ▁site ▁No . ▁ 3 ▁was ▁acquired ▁in ▁the ▁late ▁' 7 0 s ▁and ▁used ▁as ▁a ▁car ▁salv age ▁yard . ▁It ▁was ▁not ▁until ▁ 2 0 0 1 ▁when ▁the ▁Corps ▁began ▁investig ating ▁Che y enne ▁miss ile ▁sites ▁for ▁T CE ▁cont am ination , ▁that ▁a ▁" 1 . 5 - mile - long ▁cont am ination ▁pl ume ▁at ▁the ▁site , ▁[ was ▁found