Sump Pump Hole

[dadot9]

I purchased my home two months ago and started to tackle the utility room today. I discovered another hole in the floor that appears to be just like the hole about 6 feet away that contains the sump pump. Is it possible to fill in this seperate mystery hole with concrete? Right now it is covered by a rusted piece of steel, I would like to fill it and lay tile so I can build a workbench there. My basement is always dry, I have yet to have a problem with water leakage.

Also, when I moved the steel, ants scattered everywhere!

TIA, Scott

[mrcaptainbob]

Yikes! Can you shine some light in there? How big and deep is it? Are there any obvious large diameter holes entering it? Spray that sucker with some ant killer! There's got to be a good reason why it's there. That's added effort that nobody would've done without reason....

[dadot9]

Interesting huh? I shined a flashlight in there and the bottom is random stone, which has just a small look of dampness. The hole is about 1 1/2' diam, 1 1/2' depth. Is there any case where a sump pump needs another hole for air? It doesnt appear that there are any holes entering the large hole, it just looks like rock down there.

[mrcaptainbob]

That sure sounds like a candidate for a radon pit! Is there evidence around of any recently filled holes nearby that might accomadate a pvc pipe? If it wasn't, it could be used for that now! That is strange. Was there a radon check when you purchased your house?

[dadot9]

Nope..no sign of holes. The basement is finished( I believe when it was built), except for where I found the hole. The utility room with the hole is about 10' by 8' the rest is finished. What is exactly a radon pit? They didnt make us get a test for Radon because it was in a low risk zone? Ill try to get a picture of the hole tonight.

[mrcaptainbob]

Radon is a naturally acoouring radiation in the ground. Some areas of the country are higher than others. Our basement tested at 3.9 PicoCurries I believe. Can't remember what the max value allowed by EPA. Might be 4.0. the problem is breathing too much for a long enough period of time. Like smoking. May not be obvious in the first five or ten years, but.... The ways to stifle it's intrusion in the basement/crawlspaces is to seal all floor and wall cracks. Sealing any porous basement walls/floors. If you're in a high radon area, then it's best to have a radon extractor installed. Sounds fancy, but all it is, is just a pit like you have that's sealed and has a pvc pipe going to the outside. There's a fan inside that pipe that always has a negative pressure on the ground in that pit. The radon gravitates to the negative pressure and gets exhausted to the outside. (This is a simplistic description). Do a search on Google or Yahoo for Radon and you'll find some sites for a do-it-yourself system. It occurs to me, by the way, that it could've been a macerator pit for a basement toilet. Although I would expect it to have some kind of a liner. This is really intriguing.