At the current time this is not possible and TaxCalc have no plans to release a native Chromebook/ChromeOS version of the program.

It may be possible to install a supported version of Linux onto ChromeOS  and run TaxCalc in the Linux environment, but TaxCalc cannot provide technical support if there are environmental issues.

While installing Linux on a ChromeOS machine is reasonably straightforward, it does require familiarity with the terminal window and Linux in general.