Concrete Pre-cast inspection chamber for geothermal pipes

Hey all

Have just installed my ground loop pipes in the garden (600m) bringing them back to a central point outside my utility room. I have to build a chamber of some sort to put a manifold in to tie all these pipes together and take them into the house. I would like if the chamber (which will be just under ground level was large enough to get into-if any work had to be done in future years)

I realise that I can pour a concrete base and build walls but just wondering if anyone knows of any precast solutions. My geothernal installer has said they have seen large precast concrete pipes used with cover made up for them. If anyone knows of a company in the Munster area that supply such a thing could you PM their details to me please. The chamber can be any shape really, Supplier said if building it go with a 1.5m by 2m size approx and 1.5m deep. It will be backfilled around so needs to be relatively strong and needs a removable cover. It would also need approx 10 holes in the chamber to deal with pipes in and out.

One company I spoke to have a pump chamber which is round (45 '' diameter) and approx 5 ft 6'' deep for approx €350 delivered.

I can always just get a chamber built and it might be a better/cheaper solution.

Any suggestions appreciated!

Cheers