The first pressure test showed that the pool inlet jets were not holding pressure. We removed the pool wall by the steps and found a leaking plumbing joint. This was repaired and left for 24 hours. We then tested the jets again but they still lost air pressure. We then pressure tested again near the first leek using water instead of air which after 15 minutes of continual pressure created a wet area to the right hand side of the first excavation area.
We removed the AstroTurf at the side of the swimming pool and dug down until we fount the piping for the jet system. We found large splits in the pipes from the weight of large rocks due to the settling of the back fill.
We replaced all the pipe from the third inlet jet to the first repair we made with a high pressure flexible pipe. 24 hours later we pressure tested and lost no pressure, the repair was complete.
As a final precaution we pressure tested the 2 sump systems by inserting 2 T joints into the pipe work in the pool pump house. These were OK and held pressure.
Finally we carefully back filled the two excavation areas and rebuilt the stone wall by the stairs.