Dylan: Okay, if our outies are up there severing their brains, shit must have gotten pretty bad. Famine, plagues, et cetera. So what is a desperate humanity to do?
Helly: Populate the sea?
Dylan: Populate the sea. But first, they gotta send probes down there to clean up all the deadly eels and shit, 'cause we can't cohabitate with that. So we send the probes down, they send us the data coded, we sense what's eels, and then we tell the probes what to blow up.
Season 1, Episode 3, In Perpetuity (39:53)
The Work is mysterious and important, but what is it? It is all to serve Kier, but in what capacity?
Macrodata Refinement is a four-person department that scrubs macrodata files of certain numbers that evoke emotional responses. It's not always easy to see the numbers when you first begin, but eventually you learn to recognize or intuit the perimeter of the numbers representing the data that needs to be refined out of the main data. What do the macrodata files denote?
THEORY The emotional responses elicited by the numbers appear to match the bins into which the numbers are sorted. Each refiner appears to be focused on one emotional response, but all of them can be accessed and binned. Helly R took over Petey's terminal and her numbers evoke dread. At one point Mark S. offers her a chance to work on nicer feeling numbers for a while. Perhaps the four MDR workers each represent one of those Tempers and specialize in isolating the emotional response unique to themselves.
The bins have two letter abbreviations that align exactly with The Four Tempers. Kier Eagan's core philosophy centers around the pure love that is the love between the employee and his employer, and taming those emotional aspects all people carry within.
Optics and Design concerns itself with designing corporate materials, such as labels and pictogram cards, storing, restoring, and curating the paintings that hang throughout the severed floor (and in theory, the offices above, perhaps through an unsevered mediary). They also design the special totes which allow Lumon employees to take the company handbook with them when they traverse the Hallways for a mental health break. Behind a door marked storage is a huge room with many 3D printers, and seven more employees toil in this room unless there is a party in the main O&D space.
Another department with an unknown name tends to a large number of baby goats. It appears that only one employee is responsible for caring for these goats, and he seems quite overwhelmed by the task.
Because the work of Macrodata Refinement is mysterious (and important), the Refiners must come to their own conclusions about how their job affects the outside world.
Dylan George believes that the world outside has become uninhabitable, so humanity must move to the oceans. In order to rid the waters of dangerous things like eels, the refinement process must be targeting and helping to eradicate those threats to make the seas safe to live in.
Irving Bailiff believes they are taking the swear words out of movies.
Some fans of the show believe they are erasing their own or other severed employees' memories. Perhaps they are taming the tempers of lesser men. All of Kier Eagan's writings seem to indicate that he finds any emotional state other than corporate love to be abhorrent; perhaps they are expunging emotional responses from innies or other severed employees on the testing floor.