There is nothing that is an ALWAYS thing. Just like I could say humans like to shower, but there are some folks who never shower. There is also nothing that says today he doesn't dig and burrow, but tomorrow he may be happily found under his substrate.
Russians are among the champion burrowers of the tortoise world, right up there with the sulcata and Gopherus species. In the wild or outdoors, they like to burrow during the warmer months, seeking shelter from the heat of the day or the cold of the night. And of course, they brumate (hibernate) underground in the wintertime, too.
Having said that, if they're happy above ground in an indoor enclosure, they might not go to the trouble of burrowing at all. My indoor Russians dig down a little at night, and that's about all these days. Last winter they burrowed down several inches, but this year, I'm pleased to say that they are remaining active, and not really covering themselves during the day. They like their half-log caves, but they don't seem to feel the need to dig very deep anymore, at least not indoors.