Well it would be obvious. Any decent network tool would be able to filter traffic on a port or type (ICMP, DNS, etc).
“Wonder why this kid has 2.5Gb of DNS traffic last week? That isn’t normal. Maybe we should go check it out”
The trick to staying hidden is to look like noise. And this would not be noise.
I remember reading somewhere that pi to only 5 digits can calculate the circumference of the earth within an error of about 50cm. Hell NASA only uses like 15 places I think.