I work at a university that gets LN2/LHe (liquid nitrogen and helium) delivered a couple times a week by a large tanker truck outside my office. It seems to work well enough to deliver a couple tons of cryogens per week, but a rocket (e.g. Falcon 9 or Delta 4 Heavy) could use 200-600 tons of cryogens. How are they delivered to the pad?
Is it just a fleet of trucks? Are they manufactured nearby (LOx, liquid oxygen, seems easy enough to produce given lots and lots of electricity) and piped to a holding tank?