Remediated, in my world, has a very specific meaning.
Back in the years when I worked in the gas industry, it meant very specifically restoring cleared land back to its original state, making sure that it was replanted with plants that were there in the first place by either collecting seeds and plants ahead of clearance or cutting turves containing all these plants and using them to restore the land.
Saying remediated when the word remedied is simpler and more obvious is classic 'business speak' to try and make something simple sound complex. Too often the speaker doesn't actually know what the word they use means.
I saw one yesterday, where the word used was the opposite in meaning of the simple similar word that should have been used. Unfortunately I have forgotten what and where (grr, senior long movement)