A question I am commonly asked is how I managed to get my Savannah Monitor's enclosure soil to hold such nice burrows. Dank burrows in humid soil is a vital part of a Savannah Monitor's life, Without a tight fitting burrow to spend time in, the lizard's life becomes very abbreviated. Average 2 years or less. If you replicate their natural living conditions reasonably close, one can expect a lifespan of 13-20 years. For a good consitancy that will drink in water without puddling up and is easy to dig, retains humidity and most importantly holds a burrow, I have found that a mixture of plain soil dug up from an unspoiled area and play sand works very well. I know that not everyone can dig up their lawns, so it is common for people to buy organic top soil from a store. One thing to be very careful of with store bought soils is that it does not contain any fertilizers. You may have to experiment a bit for ratios, some say 60% dirt 40 sand, others say 70/30 etc. Since I was shoveling unlimited dirt, I mixed mine on the ground outside until I got a consistency like the photos below illustrate. Just like a nowball, it should hold its form when compacted, and not crumble.