Yousuf Khan wrote:

The GPS signal, like other forms of light, cannot penetrate all of the
way towards the underground mineshaft cavern where the neutrino detector
is actually located. So the GPS reading is done at the surface near the
mouth of the cavern entrance, and then the underground neutrino detector
position is estimated down nearly 1 mile underground.

I'm saying that there is plenty of room for error at this stage because
the GPS measurement is not taken at the actual neutrino detector but a
mile away, at the entrance to the neutrino detector.

Since one can accurately survey that last mile this is not a possible
source of error unless they made a flat-ass surveying mistake, something
I consider highely unlikely. Especially since they can repeat and
double-check that particular measurement as much as they like.

Steve