Gasoline Followup

Here is the message I received back from the Minnesota Pollution Control Agency:

The tank inspector for the Metro went out to the site you sent in a
citizen complaint about, and here is her response:
Jxx Mxxxx, Sxxxx, and I went to the neighborhood today. We walked
along 16th Ave NE between Buchanan and Lincoln and looked into all the
storm drains. There were no petroleum odors and we did not observe any
petroleum sheen in any of the drains. The closest gas USTs are at 1847
Johnson St NE and we felt they were too far away from the site. The gas
station at 1847 Johnson St NE was inspected in August 2003 (by me). The
other closest gas station is on the east side of 35W and again, we felt
too far away. We drove up the alley between Buchanan and Lincoln and
observed a garage (at 16h and Lincoln) that has a 55 gallon drum with
small diameter piping going from the drum into the garage. We did not
observe any leakage from the drum. To summarize, we didn’t smell any
petroleum odors, so I am considering this incident closed.

(I changed the names, as I feel these people are doing a good job and I don’t see the need to plaster their names all over the internet.)
On the one hand, I guess I am glad that whatever the problem is it is small enough that they couldn’t detect it.
On the other hand, what exactly did I observe that they couldn’t?
If I smell it again, I will try to take more notes, possibly a sample (?)….