The project is an ADA compliance contract for four MTA stations: 137th St & Broadway – Manhattan Subway, 95th St & 4th Ave – Brooklyn Subway, Northern Blvd – Queens Subway & Parkchester Station – Bronx Elevated Line. CAC was selected to perform the Con-Ed gas relocation and electric relocation that included new manhole and vault installations, DEP sewer and water main (DIP & Steel) relocation work. CAC also installed SOE for four excavations. Two excavations were for elevator shafts and two larger excavations were for subway structure extensions for elevator installations. The larger excavations required installation mini-pile soldier beams. The Brooklyn SOE required timber lagging and the Queens location required jet grout lagging between the soldier piles. CAC supported the mini-pile and jet grout operations performed by Keller. The work was performed near/adjacent to train station entrances.  Traffic conditions at some of the sites required electric duct and gas relocation work to be performed at night.  DIP water main work located below the elevated structure at Parkchester was performed at night to allow daytime work to continue uninterrupted.  The work sites had limited storage requiring material deliveries and soil disposal to be coordinated. 

Prior to commencing work, CAC examined the contract drawings and pointed out several defects involving field conditions vs. drawings.  Some issues involved obsolete records the drawing utilized; CAC was able to obtain current as-builts records to tweak water main work at two of the locations.  No records existed for a newly installed electric system, CAC was able to determine its location using google map photos and modified the relocation work accordingly.  We proposed a modified sewer manhole structure to be installed under staircase platform that was to be installed through a subway roof and could not be relocated due to the construction of extension to accommodate a new elevator shaft.  CAC proposed an alternate method to handle jet grout disposal collection using pumps in lieu of vactor trucks saving the JV money and consolidating the operation.