it ▁In frastr ucture . ▁W SK ▁was ▁responsible ▁for ▁the ▁primary ▁construction ▁work ▁for ▁Ph ases ▁ 2 / 2 A , ▁ 3 , ▁and ▁ 4 . ▁Notice ▁to ▁proceed ▁for ▁Ph ase ▁ 2 ▁pre - const ruction ▁was ▁given ▁on ▁July ▁ 1 9 , ▁ 2 0 1 3 . ▁On ▁September ▁ 2 5 , ▁ 2 0 1 3 , ▁the ▁Mass D OT ▁board ▁approved ▁a ▁$ 3 9 3 ▁million , ▁three - year ▁contract ▁with ▁W SK ▁for ▁Ph ase ▁ 2 ▁construction , ▁with ▁funds ▁from ▁the ▁transport ation ▁bill ▁passed ▁earlier ▁that ▁year . ▁ ▁Further ▁phases ▁The ▁main ▁project ▁is ▁divided ▁into ▁three ▁phases . ▁Ph ase ▁ 2 / 2 A , ▁which ▁was ▁to ▁be ▁complete ▁by ▁early ▁ 2 0 1 7 , ▁would ▁extend ▁service ▁to ▁ ▁on ▁the ▁Union ▁Square ▁Branch , ▁and ▁to ▁ ▁on ▁the ▁Med ford ▁Branch . ▁ ▁A ▁new ▁elev ated ▁ ▁station ▁and ▁a ▁substantial ▁vi ad uct ▁over ▁the ▁F itch burg ▁Line ▁would ▁be ▁built , ▁along ▁with ▁numerous ▁streets cape , ▁bridge , ▁signal ▁and ▁utility ▁improvements ▁and ▁re loc ations . ▁ ▁Ph ase ▁ 3 , ▁involves ▁the ▁construction ▁of ▁a ▁substantial ▁new ▁Green ▁Line ▁maintenance ▁facility ▁and ▁several ▁smaller ▁buildings ▁adjacent ▁to ▁the ▁MB TA ▁Comm uter ▁Rail ▁Main ten ance ▁Fac ility . ▁Ph ase ▁ 4 ▁is ▁the ▁construction ▁of ▁the ▁remainder ▁of ▁the ▁Med ford ▁Branch , ▁with ▁stations