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About 6 months ago the BI and IT groups of my company moved into a new office space.
Everything was nice and quite for several months, then about 2 months ago a person I don't know returned from maternity leave.
For 2 months straight she has done absolutely nothing except for chit chatting, gossiping, and taking personal phone calls. It's incredibly disruptive.
Our work requires a lot of concentration, thus group meetings are held in conference rooms and individuals either disable sound on their computers or wear headphones. With the hours of marathon non-stop blabbing this person does, carrying out actual work has become very difficult.
I don't believe she's ever done any actual work since she's been here and she apparently has no shame about having long, very personal, and at times offensive conversations. If she can't find someone to talk to for more than 5 minutes she leaves her desk and goes to the break room in search of company. I think she's some sort of secretary for someone who is in a different office location.
What's a good way to deal with this? Thus far we've been using headphones with white noise, but after several hours that becomes uncomfortable and it seems kind of ridiculous that all of the people who work have to wear headphones and listen to white noise just to cope with the world's worst employee.
Note that there's a fine difference between this and dealing with a loud coworker.
Someone who is simply loud can just lower their voice, without changing the frequency or content of their discussion. In this case the change needed is far bigger because we would like this person to talk 95% less often and reduce her personal conversations and gossip by 99%. Based on her behavior, I expect that she would find such a situation unbearable. It would also be nice if she did some work on occasion.