There was two leaks next to each other in a concrete irrigation box, both leaks are from the pipes rubbing against the concrete box and wore a hole in them overtime. The pipe is thin wall poly and three-quarter inch in size. The soil is all sand around the box so we were able to lift it out of the ground easily while using our hands to expose the leaks and cut them out and made the repairs with 3/4” PEX. Turned water back on and tested for leaks. We also put a protective sleeve over the pipes that we made the repairs to why are you saying PVCDWV has an outer sleeve then place the concrete box back down and filled and hole.