In California is it legal to build and operate a still for the distillation of homebrew?
No, it is not legal anywhere in the United States to distill alcohol, unless you have a license. It is not practical for individuals to get licenses for beverage alcohol.
On a side note, I hear it is relatively easy to get a home-distillation license for producing ethanol fuel. It would be illegal for you to consume that fuel, and any of it that leaves your premises must be denatured (made unfit to drink). Fuel ethanol is most commonly denatured with gasoline, since most ethanol-burning vehicles consume a mixture of up to 85% ethanol, and 15% gasoline (this is the E-85 mixture). This is something I researched in great depth a few years ago, when gas prices started climbing, and I had a pickup truck that could run on E-85. Being in New England at the time, there was not a viable fermentable source that would make economic sense to make my own fuel, so I abandoned the idea, and bought a hybrid car instead. But, I digress....alternative fuels are not really on-topic for this site....Tweet