The removal of U.S. Representatives or U.S. Senators is governed by the United States Constitution, Article 1, Sec. 5 (2), which states "Each House may determine the rules of its proceedings, punish its members for disorderly behavior, and, with the concurrence of two-thirds, expel a member." The President, Vice President and all civil officers of the United States are removed through the process of "impeachment" which is governed by the United States Constitution.
True.
> California is too big of a state
If the size of California were an issue, it would prevent recalls of the governor, as well; the reason it will never happen has nothing to do with that, it has to do with the fact that US Senators can't be recalled.
To recall a US Senator, first you have to pass an amendment to the US Constitution to make that possible.
So, its not really an option.