sealing between 2 concrete structures

huangyhg

sealing between 2 concrete structures
we are working on the modifications to an existing sanitary sewer wet well.  the goal for our project is to construct a new access tube outside of the wet well.  our work will involve the construction of a new access tube next to the wet well.  we will then need to cut an opening in the wet well wall to match the opening in our new access tube.  my concern is how to seal the interface between the ex. concrete wet well and the new concrete access tube.   
expanding water seals?  (see link)