The barrels contained concentrated soap. They came from a carwash. I washed them out a number of times before working on them. If they were not clean they wouldn't attract fish.
It takes about 30 pounds of broken brick to sink one. I drilled two 2" holes in the bottom and took the bungs out of the top. They went straight down without any trouble.
I would not think that they were illegal to use in Texas, didn't even cross my mind. I have a friend that is a Game Warden I'll call and ask.