Impossible
My grandfather hated black people. Not a little bit. A lot. He was a racist. My father wasn't a racist, but was certainly biased. He's had excellent working relationships with people not like himself, but he also tends to use a phrase Grandpa used a lot whenever he hit his thumb with a hammer or encountered a difficult-to-solve problem. He'd call it a "cotton-picker." My siblings and I don't believe ourselves to be racist at all and we all have very productive relationships with people of all kinds of genders/identities, races, ethnicities, religions... (and consider the phrase "cotton-picker," and any phrase like it, to be abhorrent).
And yet I'd be an idiot not to recognize that I have basic biases. I obviously prefer to be around people who are a lot like me (especially if they tend to like my sense of humor).
I'm going to be blunt. Really blunt. I regret being blunt, but I'm neither apologetic nor repentant at all.
Everybody has biases and everybody's first reaction to having those biases pointed out is to blame something/someone else. Only an idiot would believe it's possible to eradicate biases.
As a younger man I used to think that all society had to do to completely resolve racism (and poverty, and a host of other social "diseases") was for humanity to mature a little bit. To "grow up."
I'm older now and though many (generally below the age of 40) will disagree, the reality is that bias (in its ugliest form, racism, or any other kind of "ism" that idiots will use to justify antagonism, hatred, violence, or even simple discrimination) is simply a part of life. It's why we have law — because without a framework to force us to behave differently, those biases tend to take over.
99.9% of us spend the first 12 years of our lives, arguably the most critical years when it comes to forming basic human relationships, looking at and living with people who look just like us, believe just like us, and act just like us (or, more accurately, we learn to act like them). The fact of families creates natural bias.
99.9% of us are fundamental creatures of habit. Even when we like change, most of us don't like the process of change. As a smoker, how hard it is to stop smoking? Now ask a white person above the age of 40 how comfortable they would be watching BET television? The problem isn't black actors (I'm a HUGE fan of a lot of black actors. Sidney Piotier, Morgan Freeman, Denzel Washington, Hallie Berry, Diahann Carroll, and Thandie Newton, to name a few), but the reality is that watching all-black television is uncomfortable — not because the stories aren't engaging or because I don't like black people, but because I'm simply not used to it. I, like everyone else, am a creature of habit.
And then, there's a fundamental truth expressed by a clever advertisement for the Sniper from the game Team Fortress 2:
'Cause at the end of the day, long as there's two people left on the planet, someone is gonna want someone dead.
The fundamental bases of all bias are anger, distrust, ambition, fear, and competition. You would need to eradicate all of those emotions/circumstances to eradicate racism.
But you must eradicate human nature to do it.
We all feel anger, distrust, ambition, fear, and are competitive, at many times during our lives. We aren't racist when we choose not to allow our reactions to these things to express themselves a hatred (in one form or another) toward someone else.
So, the reality is, if you stock your colony completely with 50% white 24-year-old women and 50% white 24-year-old men, all having the same political beliefs, religious beliefs, the same genetic background, the same cultural history, the same everything, then create training programs to minimize discrimination and law to prohibit it, you'd nevertheless have bias in a week and the very same hatreds, bigotry, biases, prejudices, and problems that we would today call "racism" within a year — if only because someone thinks your job is less valuable than theirs, or your eyes less pretty, or you're a centimeter shorter, or your nose a bit longer, or you tend to use the word "sanguine" too often....
In a word, it's impossible. To forgive may be very, very divine... but to have biases is human. A story that presented the utopic idea that racism had been eradicated would, IMO, have very low credibility because anyone reading it would (at least subconsciously) know that it's fake. You could minimize it, but never eradicate it.