I just bought a new home in December of 1997. Landscaping has yet to be done. Recently, a large sink hole has appeared under about a two foot section of the sidewalk going from my driveway to my front door. The hole is about eight inches deep. The house has a one year warenty. This section of the sidewalk goes over a sewer and is "rebarred". My builder says that since this part of the sidewalk is "rebarred", just have my landscaper fill in the hole with dirt. Everyone else I talk to, including another builder, says that the hole under the sidewalk should be filled in with gravel. Any advice would be greatly appreciated. The second time I spoke to my builder about this she got hostile.