It looks like E85 is exempt from Indiana state excise taxes (18 cents per gallon).
But the retailer has to collect the tax and then apply for a credit. And it looks like there is a $1M limit to how much all E85 retailers can deduct.
I verified that Indiana charges sales tax on gas purchases. The sales tax in Indiana was recently jacked up to 7%.
So we're back to $3.13 a gallon for E85. Meijer is still charging $3.52 a gallon.