Lou,
I agree he probably doesn't need max time, and I doubt blue collar stuff like this gets it. However, it is, in effect, his second or third offense, which tends to lengthen things.
The other factor is the general tendency to amp up penalties for the issue du jour, to discourage wanton breaking of enviro laws. So, sometimes, you get more penalty for something like this than some "run of the mill" crime, even if that involves violence or theft. Doesn't always make sense to conservative, old school "law and order" types, but it is what it is. I don't think the legal system has ever been 100% consistent, although in general, I think they try.
Also to consider is that many enviro laws came into being from the 1960's-2000 era where no President/Senator/Congressman could get elected unless he was "tough on crime." I think sentencing guidelines for those "new" laws tended to be tougher. Others in the legal profession could wax more eloquently and precisely on this, but it was only in the Obama era when we started to question why our prisons were so overcrowded (compared to other countries) and took a closer look at penalties in different communities. I will say, I have seen it in my distant family - young guys committing a crime and (in Texas at least) it making it hard to recover and ever get back in the mainstream. I know they aren't terrible people, but the system doesn't allow for that at the moment. And make no mistake, whether its Texas needing the fines from marijuana use to fund the system, of Dept of Fisah and Wildlife needing to fund their next investigation, they system does make decisions based as much on financial need as "fairness.
Lastly, we are slowly transitioning into an era where big guy crimes like this are viewed more harshly than say, a poor guy doing drugs. Trump is doing nothing to slow down that trend!
No doubt that doing the "right thing" is far more relative now than it may have been just after WWII when people didn't question authority as much. As someone said, it largely depends now on who is doing the judging. We all tend to want to have stiff penalties until it comes to someone we know, then we tend to see why there could be exceptions made.
Long and short of it, we can discuss all we want, wish for the best, I doubt our thoughts get considered by those tasked with setting his punishment.