When you are doing asbestos clean-ups, you take a few samples during the work, but you take a lot of samples when the work is complete to verify that it is safe to reoccupy the space.
The workers are protected during the work by their Personal Protective Equipment (PPE), so the levels during the work are not that important. The samples taken during this time are really to make sure they are using the right PPE.
I am not saying the government did everything right, here. But the fact that 80% of the samples were taken after the clean-ups were complete is appropriate and exactly as it should have been done.
And some public servant threw all that data into an Osterizer and blipped out an irrelevant number to the public. Or else some dummy newsperson grabbed the wrong figure off of a gummint website. It would be interesting to see just where the slip happened between the cup and the lip.