[Zeke]

After the kitty, use dry cement and work it well into the pores of the concrete. The more you sweep, the better it works, then vacuum and dispose of responsibly. But, it won't finish up the job perfectly. For that you need the thinner and then a high pressure water hose (not necessarily a pressure washer). But that will get in the ground water if you're not careful. It's a tough call anymore.