Pumped sewage connection to existing manhole

[Jaysea]

I’m going to be installing a small package sewage pumping station to serve a single toilet & basin in a garden summerhouse/office. The outflow from this will be through a 50mm MDPE pipe. The intention is to discharge to an existing manhole within our garden. Two questions:

 

1)      What is the typical detail for the interface between the 50mm MDPE pipe and the manhole? I.e.: Does the pumped need to discharge into a small inspection chamber first, then gravity flow through normal 110mm pipe into the existing manhole? Or can it discharge directly into the existing manhole (which would be preferable)?

 

2)      The existing manhole is 225mm thick brickwork. What is the preferable way to form the new opening? Stitch drill or core drill? If core, is there a proprietary product, like a rubber seal, that can be used instead of grouting up around the pipe?

 

The existing drainage system is all private and discharges to a private septic tank. The drainage system is combined surface and foul.

 

Many thanks in advance!

 

Photo below for clarity: (I'm very aware that the existing set-up is contrary to good design/practice on a number of fronts, but has worked satisfactorily for several decades)