DEAR TIM: We live in a ranch-style house on a crawl on a very sandy lot.  Some of our older neighbors have told us it used to be a garbage dumping ground, which is evident by the chunks of glass that get pushed up by moles and such.

When we bought the house about 12 years ago, the owner pointed out that the dining room in the middle of the house sloped slightly.  My husband put some jacks under the center foundation walls to attempt to stabilize it and avoid further sloping.

In the last year or so, the problem has gotten significantly worse.  The door frames are cracking, one corner of our brick front has a large crack, the floors are separating from the trim at the base of the walls, and there are several cracks in the corners of some of our ceilings.  From the road, it looks as if our house will split in two at some point.

When my husband went in the crawl to investigate his options, he discovered that the foundation walls he had previously jacked up, in the center of the house, were still holding, but that the foundation walls that go around the perimeter of the house and are dug down into the ground to basically hold the weight of the house are what seem to be sinking.

We still owe a lot on our 30-year mortgage, and live check-to-check on one income to allow me to be home with our young children. We are looking for the most effective, economical way to fix our problem.  Any advice you can offer would be greatly appreciated. Misty Mulligan, Shelbyville, IN

DEAR MISTY: I'm sorry to hear about this unfortunate situation concerning your house foundation. The foundation of a house needs to sit on strong soil. If your suspicions are confirmed, that the lot was a former dump, you may have some work ahead of you. I'm convinced you can stabilize the foundation, but until you determine what the subsoil conditions are, you're wasting time and resources.

I suggest that you talk to your local government officials to see if there are records of the lot being a dump. You can also get old topographic maps that may show your lot was a ravine that has been filled in. You can often get these topographic maps from local soil engineers or universities that have a geology department.

You need to discover what the subsoil conditions are. I would also dig a test pit outdoors about 10 feet away from the foundation. This can be done by hand, but if the pit gets deeper than 4 feet, make sure you install shoring in the pit so the weak soil doesn't cave in on whomever is digging. You can also rent a very small backhoe that can dig a 10-foot-deep trench in less than 20 minutes. Be sure you have all underground utilities marked if you dig. You don't want to sever electric, gas, water or sewer lines.

Once you determine where the good soil is, you can then plan to install piers that will support your house foundation. It's hard work installing piers, but it is sometimes a do-it-yourself job. But if you discover you have to go deep to get to good soil, you will need a professional to do this.