My Garbge disposal had a leak we had a plumber fix it but in the process he pulled the pipe that lead to the sewage apart so that for about 2 months the kitchen sink was draining into the crawl space and we did not know it it has been repaired and now we have a smell coming into the house and I can't get ride of it.

Buy couple of bags of plasterer's lime, crawl under the house and disperse it over the wet area. It will dry out the dirt quickly and will kill the smell in the process. Also, it will kill bacteria.

Lime can be purchased in Home Depot or masonry yard for few bucks a bag.

Important: wear good respirator mask, gloves, goggles and overall while handling Lime.