My church has a small older house for a parsonage. I would estimate the square footage to be about 800 square feet. The house has an unfinished partial basement under about 75% of the house. About 5 years ago the family that occupied the home allowed their cats to access the crawl space under the portion of the house that wasn't over the basement. Of course the cats used this area as their litter box. This area is not really a crawl space as a person can't fit under there. I rigged up a rake to sc**** out everything I could reach, but the odor just won't go away. It has improved a little but every year when the weather warms up the odors come back. Does anyone have any suggestions on what I can do to eliminate the odors?