I live in Londonderry, NH and 2 weeks ago a sink hole opened up 50 feet on the side of my house. The sink hole is about 5+ feet deep and 2-3 feet round, with water at the bottom. However, where the sink hole is it looks like a 25 foot round section of my lawn is depressing inwards. I don't have town sewarge and the septic tank is a good 50+ feet away from it, So I don't think it could be the issues,or maybe I'm wrong?
I had the town engineer come over to inspect this and he said no sewer or other water main pipe in within this area. He thinks it the sink hole might have been caused by either building debris or tree stumps buried when the neighborhood or house was developed back in 1978. Is it possible that this could be the cause or is there somethink else? I do notice a lot of sand at the bottom of this hole.
Any suggestions on how to repair this?