Unless you're doing XC in Vermont or Colorado, 16:30 5k should be the easier of the two "standards" to hit.
I ran for a competitive D3 school, and although my coach never stipulated standards, most guys hit at least one of the following 4:25/9:40/16:10. Almost all of us got faster in college, but it took some time. Adjusting to college is difficult, and just looking at results for the younger (freshman/sophomore) runners often does not provide the whole story. I was a 4:20 guy in HS, but only ran one race under 3k as a freshman indoor and outdoor, which was a 4:25 mile at a low-key early season indoor meet. So to an outsider checking out my progression on TFRRS, I "regressed" by 5 seconds. I ended up running 4:13 the following season.
The point of my long-winded anecdote to to get you to try to evaluate a program as a whole. Look how individuals may have progressed from freshman to senior year. Look at the attrition rate (also variable, try to stay away from making assumptions about team culture or coaching staff). Also look at how athletes do at the big meets (conference, regional, nationals). Go in with the understanding that HS athletes are trained at different levels, and some, quite frankly are already burned out once they hit the college circuit.
Out of curiosity, which team was it? This could provide insight as to whether he is rebuilding a program or is a new coach, etc.