I recently found a slow water leak in the back of my closet which houses both the AC unit and the hot water heater. Maintenance came and pulled up the carpet and sprayed water/bleach on the affected area and has a fan blowing on it to help dry it out.
The leak was on the RIGHT side of the closet:
However, the LEFT side houses the AC unit which has leaked onto the carpet (now since removed) at least three times in the years that I've lived here. This is the first time that the carpet has been removed.
A water/bleach solution was sprayed only on the RIGHT side and NOT on the left under the AC unit. I looked at it today and saw that there are large white spots which appear to be fuzzy around the edges. I don't know if this is a result of the carpet installation or removal or how to tell if it is in fact mold. But it was not treated as I would guess that maintenance didn't see it as mold:
Here is a closer inspection of a white area with visible fuzz:
The maintenance personnel at this location have an air of being overworked and will sometimes leave a job unfinished, have to be reminded by a follow-up to the office, and always seem to want to just get in an get out with the least amount of effort. The regular staff in the office and the maintenance manager are great-- it's just the actual maintenance personnel that I have poor faith in both by observation and previous experience.
The wood beneath the carpet is seriously damaged but this may be historical for the life of the apartment and well before my tenancy. I don't know how long the leak has existed or how long this apartment has been here but the original building which was renovated has existed for over 100 years. I have been informed that the wood will not be replaced and I assume that they plan to put new carpet on top. As this is a closet which doesn't get any foot traffic and is not used for storage, I understand this decision, despite the appearance.
Tomorrow when maintenance returns to re-carpet, I plan to ask them to spray on the white area and come back tomorrow just in case.
This is a bit of a long-winded explanation as I felt the need to give a full account of the details and to explain why the wood looks as bad as it does even though it isn't part of the question.
So my question is: on the LEFT side where there are the large white splotches on the wood which appear to be fuzzy to my untrained eye, the same area beneath which my AC intake has leaked water onto several times, this area which was NOT sprayed, appears like it might be mold.
Could it be mold?
Bonus questions but not required for a solution:
Is it unusual for maintenance to leave the rotted wood (though dry now and treated with water/bleach) and cover it up rather than pulling it out and replacing it?
I was told by the maintenance manager who said that he worked in mold removal previously that I had mildew and did not have mold. Does this sound plausible?