is used to segregate oxygen 26 and steam 6 prior to entering the reservoir this can minimize toe corrosion and still insulate the steam line to reduce heat losses another alternative embodiment is to complete the horizontal well using a corrosion resistant material at least for the toe section of the well the horizontal well interior tubing and packers can be retrieved and reused so that its cost can be spread amongst several process units this is the least cost option capex for thin pay steam oxygen eor this is the least well count option the process has longitudinal flows with a drive recovery mechanism the production segment of the well can be isolated by fluid production if the well is drilled updip or if the toe portion of the well is drilled upward if a pump is necessary it can be accommodated e g fig1 a the design retains separate vent gas removal if steam occupies the central injection tube oxygen gas can help insulate the steam tube and minimize heat losses fig1 b and 16 c the swsagdox u version of the process allows liquids to cover the horizontal production section to prevent or inhibit gas breakthrough steam oxygen combustion gases and at the same time the gas injection zone steam oxygen is not flooded by the liquids with swsagdox hydraulic limitations need to be addressed such as if the steam oxygen section is flat and if we operate the process so that liquid covers.