 During construction , two buildings had to be evacuated in June 2009 due to construction work . On June 5 , 2009 , an apartment building at 1772 Second Avenue was evacuated by the NYC Department of Buildings ( DOB ) after it was determined that the building was in danger of collapse . Then on June 29 , 2009 , the DOB evacuated a mixed use building at 1768 Second Avenue / 301 East 92nd Street because it too was in danger of collapse . The evacuation of these two buildings delayed the contractor 's plan to use controlled blasting to remove bedrock in the southern section of the launch box . Until the blasting permits could be issued , MTA required contractors to use mechanical equipment to remove the bedrock , which is slower than blasting out the rock . 
