a question of Integrety

I have been fielding a lot of issues lately and i watch how others deal with the same things and i see why people become confused or suspicious or skeptical.

In my 33 year, i have been an investigator.
My investigations have include environmental issues, forensic cases, illness investigations and insect problems.
The same method is used - you take your best guess - do as many tests as are needed to say yea or nay , refine your guess, do more tests and come up with a conclusion.
The conclusion may be nowhere near what the first guess was or it maybe exactly.
You do not worry that what you said at first contradicts what you come out with at the end.
You completely understand that first guesses can be wrong for anyone and do not worry about it.
It seems most people are afraid of this approach, they are afraid of my conclusions, but my conclusions are based on facts and it just does not matter.
So a good example is my thoughts that arsenic should be a problem in wells - it has a number of sources, but i really have not found any in well water.  A few traces, because my limit to see Arsenic is down to 1 ug/L and the EPA set limit is 10 ug/L, the CT public health has not set a lower action limit.
So i was wrong.
I did not think lead would be an issue in run well water, but instead, i find that it is and i understand that old pumps with brass fittings (which contains lead) and old solder are down in the wells.
I found that even the older water fountains might not have lead in the water until the cooling mechanism comes on.
I learn something new daily.
A sample comes in and it is suppose to be sewage - it smells like sewage, it has all the correct look and "feel" of sewage, but there is not fecal bacteria (or minimally so).  It is not sewage.  I make that conclusion and others get frightened of that statement.
What is it?  I do not know because i was looking for sewage.  More samples and even though time has passed, it is showing something odd...not sewage, but maybe fertilizer?  The evidence points to that and everyone runs from that statement because the initial assessment was that it was sewage.