Systems are provided including a selective catalytic reduction catalyst structured to receive first exhaust gas from a first fuel source of a dual fuel engine system and second exhaust gas from a second fuel source of the dual fuel engine system, a first fuel of the first fuel source differing from a second fuel of the second fuel source, an ammonia slip catalyst positioned downstream of the selective catalytic reduction catalyst to receive a flow of exhaust gases from the selective catalytic reduction catalyst without an intervening catalyst, and an oxidation catalyst positioned downstream of the ammonia slip catalyst to receive the flow of exhaust gases from the ammonia slip catalyst without an intervening catalyst.