You need primary treatment to ...

You need primary treatment to remove TSS and O/G through a DAF or like.  This will save you headaches.  Consistent feed to the secondary biological system is critical, so make sure you have 2.5-3.5 days of storage at higher flow rates.  Do any toxicity testing ahead of time.  Never hurts to add a couple of tanks for hydrogen peroxide to the system.  1.  One at the DAF to increase the ORP for enhanced coagulation and one at the bios for extra oxygen during high loading.  Plan for a bad day and not wait until you have one.  Hydrogen peroxide loses 1% effectiveness per year in proper storage tank.  If you use 26%, then you can get around reporting as this makes it a class 1 oxidizer.  Jar test many combinations of coagulants and flocculants at both primary and secondary.  Calculate your sludge production to size your dewatering x 1.5 the top of calculation.  Again, plan for a bad day.  You will thank me later.