The question of whether it is irresponsible is pure opinion, which we can't answer. We can, however, address the question of legality. Federal regulations apply to "public water systems". In the salient definitions, 42 USC 300f(4)(A) says that
The term “public water system” means a system for the provision to the
public of water for human consumption through pipes or other
constructed conveyances, if such system has at least fifteen service
connections or regularly serves at least twenty-five individuals.
Assuming that there are at least 25 individuals being so served, it must be determined whether the water is being "provided to the public", and that isn't obvious. However, 42 USC 300g says that the regulations do not apply to a system
(1) which consists only of distribution and storage facilities (and
does not have any collection and treatment facilities); (2) which
obtains all of its water from, but is not owned or operated by, a
public water system to which such regulations apply; (3) which does
not sell water to any person; and (4) which is not a carrier which
conveys passengers in interstate commerce.
It is most likely that all of these conditions are true, so federal testing requirements do not apply. This does not preclude there being state regulations, which may well be more stringent (though they tend to copy the federal rules), but we'd need to know the state.
[Addendum]
New Jersey adopted the federal regulations unchanged. The issue over lead in the water is that corrosive water can leach lead from the plumbing into the water. There is a testing procedure and a threshold of acceptable lead where the town doesn't have to do anything, and above that they are supposed to treat the water (and if they don't, you have the Flint problem). The testing involves sampling at the tap, and if there is more that 0.015 mg/L lead in more than 10% of samples, the supplier is supposed to take corrosion-control steps. There are also lead service line regulations. There being regulations which put the onus of the problem on the water supplier, and no rules which obligate owners of buildings to rip out existing lead plumbing, the public has not generally been aware of the potential hazard, and it is unlikely that a university could be sued because / if it has some lead in its plumbing that leached into the water (assuming that the lead comes from the university, and not the city supply lines). Of course they could have done something to contribute to the problem, in which case there could be some liability.