My state has operators in training (apprenticeship) programs that do not require a grade to get into. Usually they are offered at the municipal level, have you looked into something like that? Though having your grade 1 or even a 2 would make you stand out from the crowd.
I'm in the drinking water industry so I can't really help you out with much more than that, maybe get familiar with your different type of pumps (centrifugal, positive displacement, etc.) For the most part though you will do most of your learning on the job as you come across real world issues.
You seem to be on the right track, just keep an open mind, have a willingness to learn and you will be fine. A couple guys I work with that have their certs in Wastewater swear by this site, so maybe it can you help you. Best of luck.